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Sample records for calcium foliar application

  1. EFFECT OF FOLIAR APPLICATION OF UREA WITH NBPT ON THE PHYSIOLOGY AND YIELD OF COTTON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Urea is the most recommended foliar N source, due to its relatively low toxicity, quick absorption, and low cost. However, reports of yield improvements with foliar urea application are not consistent. The objectives of this research were to study foliar urea assimilation in cotton and to test the ...

  2. Foliar nickel application alleviates detrimental effects of glyphosate drift on yield and seed quality of wheat.

    PubMed

    Kutman, Bahar Yildiz; Kutman, Umit Baris; Cakmak, Ismail

    2013-09-01

    Glyphosate drift to nontarget crops causes growth aberrations and yield losses. This herbicide can also interact with divalent nutrients and form poorly soluble complexes. The possibility of using nickel (Ni), an essential divalent metal, for alleviating glyphosate drift damage to wheat was investigated in this study. Effects of Ni applications on various growth parameters, seed yield, and quality of durum wheat ( Triticum durum ) treated with sublethal glyphosate at different developmental stages were investigated in greenhouse experiments. Nickel concentrations of various plant parts and glyphosate-induced shikimate accumulation were measured. Foliar but not soil Ni applications significantly reduced glyphosate injuries including yield losses, stunting, and excessive tillering. Both shoot and grain Ni concentrations were enhanced by foliar Ni treatment. Seed germination and seedling vigor were impaired by glyphosate and improved by foliar Ni application to parental plants. Foliar Ni application appears to have a great potential to ameliorate glyphosate drift injury to wheat. PMID:23882996

  3. Foliar application of two silica sols reduced cadmium accumulation in rice grains.

    PubMed

    Liu, Chuanping; Li, Fangbai; Luo, Chunling; Liu, Xinming; Wang, Shihua; Liu, Tongxu; Li, Xiangdong

    2009-01-30

    In the present study, pot experiments were conducted to investigate the effects of foliar application of two silica (Si) sols on the alleviation of cadmium (Cd) toxicity in contaminated soil to rice. Results showed that the foliar application of Si sols significantly increased the dry weight of grains (without husk) and shoots in rice grown in Cd contaminated soil, whereas the Cd concentration in the grains and shoots decreased obviously. The total accumulation of Cd in rice grains also decreased with the application of both of the Si sols, but no significant effect was found on the Cd accumulation in the shoots. For the optimal effect, Si-sol-B should be foliar applied at the tillering-stage during rice growth. The mechanism of Si foliar application to alleviate the toxicity and accumulation of Cd in grains of rice may be related to the probable Cd sequestration in the shoot cell walls. PMID:18555602

  4. Effects of foliar sprays containing calcium, magnesium and titanium on plum (Prunus domestica L.) fruit quality.

    PubMed

    Alcaraz-Lopez, Carlos; Botia, Maria; Alcaraz, Carlos F; Riquelme, Fernando

    2003-12-01

    An experiment was performed in which Ti(4+)-ascorbate was sprayed onto plum trees in several combinations with other commercial compounds containing Ca2+ and Mg2+ to study the effects on the commercial quality of fruits, with special focus on improving their resistance against postharvest handling damage. All the treatments containing titanium increased the tree performance (branch elongation, flowering and fruit setting intensities) and fruit size. At harvest fruits from the Ti-treated trees showed improved resistance to compression and penetration, as well as a decrease in weight-loss during postharvest storage. A similar response was obtained for the external colour, though all the treatments seemed to delay somewhat the apparent ripening status. Nevertheless, the fruits from Ti-treated trees showed a better behaviour in the evolution of the colour parameters during storage than did the control fruits. Titanium application significantly increased the calcium, iron, copper and zinc concentrations in peel and flesh. This improvement in the calcium absorption is explained as a consequence of the beneficial effect of titanium on the absorption, translocation and assimilation processes. PMID:14717435

  5. Effects of boron foliar applications on vegetative and reproductive growth of sunflower.

    PubMed

    Asad, A; Blamey, F P C; Edwards, D G

    2003-10-01

    Foliar application may be used to supply boron (B) to a crop when B demands are higher than can be supplied via the soil. While B foliar sprays have been used to correct B deficiency in sunflower (Helianthus annuus L.) in the field, no studies have determined the amount of B taken up by sunflower plant parts via foliar application. A study was conducted in which sunflower plants were grown at constant B concentration in nutrient solution with adequate B (46 micro m) or with limited B supply (0.24, 0.40 and 1.72 micro m) using Amberlite IRA-743 resin to control B supply. At the late vegetative stage of growth (25 and 35 d after transplanting), two foliar sprays were applied of soluble sodium tetraborate (20.8 % B) each at 0, 28, 65, 120 and 1200 mm (each spray equivalent to 0, 0.03, 0.07, 0.13 and 1.3 kg B ha-1 in 100 L water ha-1). The highest rate of B foliar fertilization resulted in leaf burn but had no other evident detrimental effect on plant growth. Under B-deficient conditions, B foliar application increased the vegetative and reproductive dry mass of plants. Foliar application of 28-1200 mm B increased the total dry mass of the most B-deficient plants by more than three-fold and that of plants grown initially with 1.72 micro m B in solution by 37-49 %. In this latter treatment, the dry mass of the capitulum was similar to that achieved under control conditions, but in no instance was total plant dry mass similar to that of the control. All B foliar spray rates increased the B concentration in various parts of the plant tops, including those that developed after the sprays were applied, but the B concentration in the roots was not increased by B foliar application. The B concentration in the capitulum of the plants sprayed at the highest rate was between 37 and 93 % of that in the control plants. This study showed that B foliar application was of benefit to B-deficient sunflower plants, increasing the B status of plant tops, including that of the capitulum which developed after the B sprays were applied. PMID:12933368

  6. Methyl jasmonate foliar application to Tempranillo vineyard improved grape and wine phenolic content.

    PubMed

    Portu, Javier; Santamara, Pilar; Lpez-Alfaro, Isabel; Lpez, Rosa; Garde-Cerdn, Teresa

    2015-03-01

    The importance of phenolic compounds for grape and wine quality has drawn attention to studying different practices with the aim of increasing their content. Cluster application of elicitors is a viticultural practice that has shown promising results in recent years. However, cluster application requires a previous defoliation, which is time-consuming and expensive. In the present study, methyl jasmonate was foliar applied to Tempranillo grapevines in order to study its effect on grape and wine phenolic composition. Methyl jasmonate foliar application increased anthocyanin and stilbene content in both grape and wine, besides enhancing wine flavonol content. This treatment induced the synthesis of 3-O-glucosides of petunidin and peonidin and trans-p-coumaroyl derivatives of cyanidin and peonidin. For stilbenes, trans-piceid content was considerably increased in both grape and wine. The results obtained suggest that methyl jasmonate foliar application could be a simple and accessible practice to enhance grape and wine quality. PMID:25672964

  7. Changes on grape phenolic composition induced by grapevine foliar applications of phenylalanine and urea.

    PubMed

    Portu, J; Lpez-Alfaro, I; Gmez-Alonso, S; Lpez, R; Garde-Cerdn, T

    2015-08-01

    Grapevines may require the input of nitrogen to grow and to guarantee an appropriate grape composition. Recently there has been a growing interest in foliar fertilization, which entails a fast and efficient assimilation of the products. The aim of this work was to study the influence of foliar applications of phenylalanine and urea, at two different doses, on grape anthocyanins, flavonols, flavan-3-ols, phenolic acids, and stilbenes. All treatments were applied at veraison and one week later at doses of 0.9 and 1.5 kg N/ha. The results showed that the synthesis of phenolic compounds was favoured by foliar applications of phenylalanine and urea. The application of the lowest dose of urea was the most effective treatment, increasing the content of several anthocyanins and flavonols. Moreover, none of the foliar treatments worsened the grape phenolic composition. In conclusion, foliar application of phenylalanine and especially urea, could be an interesting management tool for improving grape quality and their health-promoting properties. PMID:25766815

  8. Influence of calcium foliar fertilization on plant growth, nutrient concentrations, and fruit quality of papaya.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium (Ca) is a major plant nutrient that affects cell wall and plasma membrane formation and plays a key role in plant growth and biomass production. It can be used to decrease fruit decay and increase firmness and shelf life. So far, little attention has been paid to investigate the effects of f...

  9. Nitrogen metabolism and seed composition as influenced by foliar boron application in soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of foliar boron (B) application on nitrogen metabolism and seed composition in soybean was not well investigated, especially under water stress conditions. Nonirrigated field experiment and watered (W) and water-stressed (WS) greenhouse experiments were conducted to investigate the effect...

  10. EFFECT OF FOLIAR APPLICATION OF PARTICLE FILMS ON DROUGHT STRESS AND AFLATOXIN CONTAMINATION OF PEANUT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar application of Kaolin-based particle films has been shown to suppress insect pests and diseases in tree fruit, and to improve transpiration efficiency. Drought tolerant peanut lines have been shown to have greatly reduced aflatoxin contamination. The objective of this study was to evaluate ...

  11. Application of Calcium Phosphate Materials in Dentistry

    PubMed Central

    Al-Sanabani, Jabr S.; Al-Sanabani, Fadhel A.

    2013-01-01

    Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1) application of calcium phosphate into various fields in dentistry; (2) improving mechanical properties of calcium phosphate; (3) biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials such as hydroxyapatite and tricalcium phosphate which are currently used in dental and medical fields. PMID:23878541

  12. The response of broccoli (Brassica oleracea convar. italica) varieties on foliar application of selenium: uptake, translocation, and speciation.

    PubMed

    indel?ov, Kristna; Szkov, Ji?ina; Tremlov, Jana; Mestek, Oto; Praus, Luk; Ka?a, Antonn; Najmanov, Jana; Tlusto, Pavel

    2015-12-01

    A model small-scale field experiment was set up to investigate selenium (Se) uptake by four different varieties of broccoli plants, as well as the effect of Se foliar application on the uptake of essential elements for plants calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), phosphorus (P), sulfur (S), and zinc (Zn). Foliar application of sodium selenate (Na2SeO4) was carried out at two rates (25 and 50g Se/ha), and an untreated control variant was included. Analyses of individual parts of broccoli were performed, whereby it was found that Se in the plant accumulates mainly in the flower heads and slightly less in the leaves, stems, and roots, regardless of the Se rate and broccoli variety. In most cases, there was a statistically significant increase of Se content in all parts of the plant, while there was no confirmed systematic influence of the addition of Se on the changing intake of other monitored elements. Selenization of broccoli leads to an effective increase in the Se content at a rate of 25g/ha, whereas the higher rate did not result in a substantial increase of Se content compared to the lower rate in all varieties. Therefore, the rate of 25g/ha can be recommended as effective to produce broccoli with an increased Se content suitable for consumption. Moreover, Se application resulted in an adequate increase of the main organic compounds of Se, such as selenocystine (SeCys2), selenomethionine (SeMet), and Se-methylselenocysteine (Se-MeSeCys). PMID:26414440

  13. Phenylalanine and urea foliar applications to grapevine: effect on wine phenolic content.

    PubMed

    Portu, J; Gonzlez-Arenzana, L; Hermosn-Gutirrez, I; Santamara, P; Garde-Cerdn, T

    2015-08-01

    Phenolic compounds play a key role in the organoleptic properties of wines. Viticultural practices may influence grape and wine phenolic content, thus determining their quality. The objective of this study was to evaluate the effect of foliar applications of phenylalanine and urea, at two different doses, on wine phenolic composition. Grapes were harvested at their optimal technological maturity and their respective wines were elaborated at small scale. Wine detailed phenolic composition was determined. Results revealed that the content of several anthocyanins and flavonols was enhanced by the application of both phenylalanine doses and by the application of the low dose of urea. In contrast, flavanols and non-flavonoid compounds were less affected by the foliar treatments. The findings seem to be related to the time of application, since anthocyanins and flavonols are accumulated after veraison. In conclusion, nitrogen foliar fertilization increased the phenolic content of Tempranillo wines. This could be of interest since anthocyanins and flavonols are associated with wine quality, especially with its color. PMID:25766801

  14. Foliar application of brassinosteroids alleviates adverse effects of zinc toxicity in radish (Raphanus sativus L.) plants.

    PubMed

    Ramakrishna, Bellamkonda; Rao, S Seeta Ram

    2015-03-01

    Growth chamber experiments were conducted to investigate the comparative effect of 24-epibrassinolide (EBL) and 28-homobrassinolide (HBL) at 0.5, 1.0, or 2.0 ?M concentrations by foliar application on radish plants growing under Zn(2+) stress. In radish plants exposed to excess Zn(2+), growth was substantially reduced in terms of shoot and root length, fresh and dry weight. However, foliar application of brassinosteroids (BRs) was able to alleviate Zn(2+)-induced stress and significantly improve the above growth traits. Zinc stress decreased chlorophyll a, b, and carotenoids levels in radish plants. However, follow-up treatment with BRs increased the photosynthetic pigments in stressed and stress-free plants. The treatment of BRs led to reduced levels of H2O2, lipid peroxidation and, electrolyte leakage (ELP) and improved the leaf relative water content (RWC) in stressed plants. Increased levels of carbonyls indicating enhanced protein oxidation under Zn(2+) stress was effectively countered by supplementation of BRs. Under Zn(2+) stress, the activities of catalase (CAT), ascorbate peroxidase (APX), and superoxidase dismutase (SOD) were increased but peroxidase (POD) and glutathione reductase (GR) decreased. Foliar spraying of BRs enhanced all these enzymatic activities in radish plants under Zn(2+) stress. The BRs application greatly enhanced contents of ascorbate (ASA), glutathione (GSH), and proline under Zn(2+) stress. The decrease in the activity of nitrate reductase (NR) caused by Zn(2+) stress was restored to the level of control by application of BRs. These results point out that BRs application elevated levels of antioxidative enzymes as well as antioxidants could have conferred resistance to radish plants against Zn(2+) stress resulting in improved plant growth, relative water content and photosynthetic attributes. Of the two BRs, EBL was most effective in amelioration of Zn(2+) stress. PMID:25308099

  15. Foliar potassium nitrate application improves the tolerance of Citrus macrophylla L. seedlings to drought conditions.

    PubMed

    Gimeno, V; Daz-Lpez, L; Simn-Grao, S; Martnez, V; Martnez-Nicols, J J; Garca-Snchez, F

    2014-10-01

    Scarcity of water is a severe limitation in citrus tree productivity. There are few studies that consider how to manage nitrogen (N) nutrition in crops suffering water deficit. A pot experiment under controlled-environment chambers was conducted to explore if additional N supply via foliar application could improve the drought tolerance of Citrus macrophylla L. seedlings under dry conditions. Two-month-old seedlings were subjected to a completely random design with two water treatments (drought stress and 100% water/field capacity). Plants under drought stress (DS) received three different N supplies via foliar application (DS: 0, DS+NH4NO3: 2% NH4NO3, DS+KNO3: 2% KNO3). KNO3-spraying increased leaf and stem DW as compared with DS+NH4NO3 and DS treatments. Leaf water potential (?w) was decreased by drought stress in all the treatments. However, in plants from DS+NH4NO and DS+KNO3, this was due to a decrease in the leaf osmotic potential, whereas the decrease in those from the DS treatment was due to a decrease in the leaf turgor potential. These responses were correlated with the leaf proline and K concentrations. DS+KNO3-treated plants had a higher leaf proline and K concentration than DS-treated plants. In terms of leaf gas exchange parameters, it was observed that net assimilation of CO2 [Formula: see text] was decreased by drought stress, but this reduction was much lower in DS+KNO3-treated plants. Thus, when all results are taken into account, it can be concluded that a 2% foliar-KNO3 application can enhance the tolerance of citrus plants to water stress by increasing the osmotic adjustment process. PMID:25218731

  16. Foliar application with nano-silicon alleviates Cd toxicity in rice seedlings.

    PubMed

    Wang, Shihua; Wang, Fayuan; Gao, Shuangcheng

    2015-02-01

    Nanofertilizers may be more effective than regular fertilizers in improving plant nutrition, enhancing nutrition use efficiency, and protecting plants from environmental stress. A hydroponic pot experiment was conducted to study the role of foliar application with 2.5 mM nano-silicon in alleviating Cd stress in rice seedlings (Oryza sativa L. cv Youyou 128) grown in solution added with or without 20 μM CdCl2. The results showed that Cd treatment decreased the growth and the contents of Mg, Fe, Zn, chlorophyll a, and glutathione (GSH), accompanied by a significant increase in Cd accumulation. However, foliar application with nano-Si improved the growth, Mg, Fe, and Zn nutrition, and the contents of chlorophyll a of the rice seedlings under Cd stress and decreased Cd accumulation and translocation of Cd from root to shoot. Cd treatment produced oxidative stress to rice seedlings indicated by a higher lipid peroxidation level (as malondialdehyde (MDA)) and higher activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and a lower GSH content. However, those nano-Si-treated plants had lower MDA but higher GSH content and different antioxidant enzyme activities, indicating a higher Cd tolerance in them. The results suggested that nano-Si application alleviated Cd toxicity in rice by decreasing Cd accumulation, Cd partitioning in shoot and MDA level and by increasing content of some mineral elements (Mg, Fe, and Zn) and antioxidant capacity. PMID:25217281

  17. Physiological responses of Tillandsia albida (Bromeliaceae) to long-term foliar metal application.

    PubMed

    Kov?ik, Jozef; Klejdus, Bo?ivoj; Stork, Frantiek; Hedbavny, Josef

    2012-11-15

    The impact of 2-month foliar application of cadmium, nickel and their combination (10 ?M) on Tillandsia albida was studied. Cadmium caused damage of tissue but assimilation pigments were depressed in Cd+Ni variant only. Stress-related parameters (ROS and peroxidase activities) were elevated by Cd and Cd+Ni while MDA content remained unaffected. Free amino acids accumulated the most in Ni alone but soluble proteins were not influenced. Among phenolic acids, mainly vanillin contributed to increase of their sum in all variants while soluble phenols even decreased in Cd+Ni and flavonols slightly increased in Cd variants. Phenolic enzymes showed negligible responses to almost all treatments. Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by metal application but N content increased. Total Cd or Ni amounts reached over 400 ?g g(-1) DW and were not affected if metal alone and combined treatment is compared while absorbed content differed (ca. 50% of total Cd was absorbed while almost all Ni was absorbed). These data indicate tolerance of T. albida to foliar metal application and together with strong xerophytic morphology, use for environmental studies is recommended. PMID:22989857

  18. Premixed calcium silicate cement for endodontic applications

    PubMed Central

    Persson, Cecilia; Engqvist, Hkan

    2011-01-01

    Calcium silicate-based materials (also called MTA) are increasingly being used in endodontic applications. However, the handling properties of MTA are not optimal when it comes to injectability and cohesion. Premixing the cements using glycerol avoids these issues. However, there is a lack of data on the effect of common cement variables on important properties of premixed cements for endodontic applications. In this study, the effects of liquid-to-powder ratio, amount of radiopacifier and amount of calcium sulfate (added to control the setting time) were screened using a statistical model. In the second part of the study, the liquid-to-powder ratio was optimized for cements containing three different amounts of radiopacifier. Finally, the effect of using glycerol rather than water was evaluated in terms of radiopacity. The setting time was found to increase with the amount of radiopacifier when the liquid-to-powder ratio was fixed. This was likely due to the higher density of the radiopacifier in comparison to the calcium silicate, which gave a higher liquid-to-powder ratio in terms of volume. Using glycerol rather than water to mix the cements led to a decrease in radiopacity of the cement. In conclusion, we were able to produce premixed calcium silicate cements with acceptable properties for use in endodontic applications. PMID:23507729

  19. Effect of soil and foliar application of zinc on grain zinc and cadmium concentration of wheat genotypes differing in Zn-efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A two-year field experiment was carried out to investigate the effectiveness of soil and foliar applications of zinc sulfate and soil application of waste rubber ash to increase Zn and decrease cadmium (Cd) concentration in grain of 10 wheat genotypes with different Zn-efficiency. Foliar spray of zi...

  20. Effects of foliar boron application on seed composition, cell wall boron, and seed delta 15N and delta 13C isotopes in soybean are influenced by water stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although the effect of foliar boron (B) application on yield and quality is well established for crops, limited information and controversial results still exist on the effects of foliar B application on soybean seed composition (seed protein, oil, fatty acids, and sugars). The objective of this res...

  1. Effect of water stress and foliar boron application on seed protein oil fatty acids and nitrogen metabolism in soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of water stress and foliar boron (FB) application on soybean (Glycine max (L) Merr.) seed composition and nitrogen metabolism have not been well investigated. Therefore, the objective of this study was to investigate the effects of water stress and FB on seed protein, oil, fatty acids, nitra...

  2. Influence of plant culture conditions on efficacy of foliar applications of entomopathogenic fungi against western flower thrips

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of greenhouse tests was conducted to assess the efficacy of foliar applications of two commercially available entomopathogenic fungi, Beauveria bassiana strain GHA and Metarhizium brunneum strain F52, against western flower thrips infesting potted impatiens grown with subirrigation. Unformu...

  3. Improving efficacy of Beauveria bassiana foliar treatments against Colorado potato beetle via manipulation of spray-application parameters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of hydraulic spray pressure and sprayer configuration on efficacy of foliar applications of B. bassiana against Leptinotarsa decemlineata larvae were evaluated during 4 field seasons. Treatments were applied to small plots using a tractor-mounted sprayer with nozzles mounted on swivels on sh...

  4. Effect of foliar and soil application of potassium fertilizer on soybean seed protein, oil, fatty acids, and minerals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this research was to evaluate the effectiveness of soil and foliar application of potassium (K) on leaf and seed mineral concentration levels, and seed composition (protein, oil, fatty acids, and minerals). Soybean cultivar (Pioneer 95470) of maturity group 5.7 was grown in a repeat...

  5. Seed protein, oil, fatty acids, and minerals concentration as affected by foliar K-glyphosate application in soybean cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies showed that glyphosate (Gly) may chelate cation nutrients, including potassium (K), which might affect the nutritional status of soybean seed. The objective of this study was to evaluate seed composition (protein, oil, fatty acids, and minerals) as influenced by foliar applications ...

  6. Foliar nickel application can increase the incidence of peach tree short life and consequent peach tree mortality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of postplant nickel (Ni) foliar application to suppress Mesocriconema xenoplax populations and thereby prolong tree survival of peach trees on a peach tree short life (PTSL) site was investigated from 2004-2011. The study was conducted in an orchard infested with M. xenoplax and a histo...

  7. Foliar Application of Phosphorus Has Minimal Impact on 'Pinot noir' Growth, Mycorrhizal Colonization, or Fruit Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapevines grown in low phosphorus (P) soils typical of western Oregon vineyards may benefit from additional P applied to the canopy using foliar sprays. Alternatively, vines may be negatively affected by foliar P sprays because lower root colonization by arbuscular mycorrhizal fungi (AMF) could red...

  8. The effect of foliar application of phosphonate formulations on the susceptibility of potato tubers to late blight.

    PubMed

    Cooke, Louise R; Little, George

    2002-01-01

    Foliar sprays of potato plants with phosphonic acid (partially neutralised with potassium hydroxide to pH 6.4) substantially reduced infection of the tubers by Phytophthora infestans, the cause of late blight, in glasshouse and field experiments over a 4-year period. Healthy tubers of blight-susceptible cultivars removed from treated plants and artificially inoculated by spraying with sporangial/zoospore suspensions of P infestans did not develop disease symptoms, demonstrating that the phosphonate applications had directly reduced the susceptibility of tubers to infection, probably as a result of translocation into tuber tissue. In contrast, foliar application of fosetyl-aluminium did not significantly reduce tuber blight development following inoculation. Five to six sprays of partially neutralised phosphonic acid (2 kg ha-1) applied at 10-14 day intervals resulted in the least tuber infection, but such a treatment regime may not be economic. In trials where the effect of timing and rate of application of 2-4 kg phosphonic acid ha-1 was examined, a single treatment of 4 kg ha-1 applied mid- or late-season proved the most effective. A spray programme in which one or two applications of phosphonic acid are combined with use of a non-systemic or systemic fungicide to enhance foliar protection offers the possibility of controlling both foliage and tuber blight and could have a major impact in reducing overwinter survival of P infestans in tubers. PMID:11838279

  9. Foliar application of glyphosate affects molecular mechanisms in underground adventitious buds of leafy spurge (Euphorbia esula) and alters their vegetative growth patterns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Long term control of leafy spurge with glyphosate requires multiple applications because the plant reproduces vegetatively from abundant underground adventitious buds (UABs). Determining the molecular mechanisms involved in controlling vegetative reproduction in leafy spurge following foliar glyphos...

  10. 40 CFR 415.50 - Applicability; description of the calcium oxide production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium oxide production subcategory. 415.50 Section 415.50 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium... the production of calcium oxide....

  11. 40 CFR 415.30 - Applicability; description of the calcium carbide production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium carbide production subcategory. 415.30 Section 415.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium... the production of calcium carbide in uncovered furnaces....

  12. 40 CFR 415.30 - Applicability; description of the calcium carbide production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium carbide production subcategory. 415.30 Section 415.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium... the production of calcium carbide in uncovered furnaces....

  13. 40 CFR 415.50 - Applicability; description of the calcium oxide production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium oxide production subcategory. 415.50 Section 415.50 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium... the production of calcium oxide....

  14. 40 CFR 415.50 - Applicability; description of the calcium oxide production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium oxide production subcategory. 415.50 Section 415.50 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium... the production of calcium oxide....

  15. 40 CFR 415.30 - Applicability; description of the calcium carbide production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium carbide production subcategory. 415.30 Section 415.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium... the production of calcium carbide in uncovered furnaces....

  16. 40 CFR 415.50 - Applicability; description of the calcium oxide production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium oxide production subcategory. 415.50 Section 415.50 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium... the production of calcium oxide....

  17. 40 CFR 415.30 - Applicability; description of the calcium carbide production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium carbide production subcategory. 415.30 Section 415.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium... the production of calcium carbide in uncovered furnaces....

  18. 40 CFR 415.30 - Applicability; description of the calcium carbide production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium carbide production subcategory. 415.30 Section 415.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium... the production of calcium carbide in uncovered furnaces....

  19. 40 CFR 415.50 - Applicability; description of the calcium oxide production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium oxide production subcategory. 415.50 Section 415.50 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium... the production of calcium oxide....

  20. Foliar boron and nickel applications reduce water-stage fruit-split of pecan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water-stage fruit-split (WSFS) is a relatively common and often major problem of certain pecan [Carya illinoinensis (Wangenh.) K. Koch] cultivars. This study evaluates the possibility that the malady can be influenced by improving tree micronutrient nutrition. Foliar sprays of boron (B) and nickel...

  1. Response of young bearing pecan trees to spring foliar nickel applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The lower critical leaf concentration for nickel (Ni) has not been fully determined for commercial pecan [Carya illinoinensis (Wang.) K. Koch.] orchards. In a two-year study, foliar Ni was applied to orchard trees in early spring beginning at the parachute stage of leaf development and followed by ...

  2. Increasing Selenium and Yellow Pigment Concentrations in Foxtail Millet (Setaria italica L.) Grain with Foliar Application of Selenite.

    PubMed

    Ning, Na; Yuan, Xiang-Yang; Dong, Shu-Qi; Wen, Yin-Yuan; Gao, Zhen-Pan; Guo, Mei-Jun; Guo, Ping-Yi

    2016-03-01

    Although addition of selenium (Se) is known to increase Se in crops, it is unclear whether exogenous Se is linked to nutritional and functional components in foxtail millet (Setaria italica L.). In this study, we examined the potential of increasing Se and yellow pigment (YP) in foxtail millet grain by foliar application of Se. Field experiments were conducted during the growing season of foxtail millet in 2013 and 2014 to assess the effects of foliar spray of sodium selenite (10-210 g Se ha(-1)) on the yield, Se uptake and accumulation, total YP, and microminerals in the grain. Average grain yields with Se application were 5.60 and 4.53 t ha(-1) in the 2 years, showing no significant differences from the unfertilized control. However, grain Se concentration increased linearly with Se application rate, by 8.92 and 6.09 μg kg(-1) in the 2 years with application of 1 g Se ha(-1) (maximum grain recovery rates of Se fertilizer, 52 and 28 %). Likewise, total grain YP concentration markedly increased by 0.038 and 0.031 mg kg(-1) in the 2 years with application of 1 g Se ha(-1). Grain Mn, Cu, Fe, and Zn concentrations were not significantly affected by Se application. This study indicated that foliar application of Se effectively and reliably increased the concentrations of Se and YP in foxtail millet grain without affecting the yield or mineral micronutrient concentrations. Thus, foliar-applied selenite has a significant potential to increase the concentrations of selenium and YP (putative lutein (Shen, J Cereal Sci 61:86-93, 2015; Abdel-Aal, Cereal Chem 79:455-457, 2002; Abdel-Aal, J Agric Food Chem 55:787-794, 2007)) of foxtail millet and, thus, the health benefits of this crop. PMID:26201681

  3. Calcium.

    PubMed

    Williams, Robert J P

    2002-01-01

    This chapter describes the chemical and biological value of the calcium ion. In calcium chemistry, our main interest is in equilibria within static, nonflowing systems. Hence, we examined the way calcium formed precipitates and complex ions in solution. We observed thereafter its uses by humankind in a vast number of materials such as minerals, e.g., marble, concrete, mortars, which parallel the biological use in shells and bones. In complex formation, we noted that many combinations were of anion interaction with calcium for example in the uses of detergents and medicines. The rates of exchange of calcium from bound states were noted but they had little application. Calcium ions do not act as catalysts of organic reactions. In biological systems, interest is in the above chemistry, but extends to the fact that Ca2+ ions can carry information by flowing in one solution or from one solution to another through membranes. Hence, we became interested in the details of rates of calcium exchange. The fast exchange of this divalent ion from most organic binding sites has allowed it to develop as the dominant second messenger. Now the flow can be examined in vitro as calcium binds particular isolated proteins, which it activates as seen in physical mechanical changes or chemical changes and this piece-by-piece study of cells is common. Here, however, we have chosen to stress the whole circuit of Ca2+ action indicating that the cell is organized both at a basal and an activated state kinetic level by the steady state flow of the ion (see Fig. 11). Different time constants of exchange utilizing very similar binding constants lead to: 1) fast responses as in the muscle of an animal; or 2) slower change as in differentiation of an egg or seed. Many other changes of state may relate to Ca2+ steady-state levels of flow in the circuitry and here we point to two: 1) dormancy in reptiles and animals; and 2) sporulation in both bacteria and lower plants. In the other chapters of this volume many components of the overall circuitry will be described. The reader should try to marry these into the overall activity of the cell for on top of molecular biology there is the cooperative system molecular biology of cells. To give an analogy, whereas much can be understood from the analysis of the properties of single-isolated water molecules, even examining their interaction in ice, this study alone cannot lead to an appreciation of the melting or boiling points of bulk water. PMID:11833348

  4. Calcium

    MedlinePLUS

    ... edamame). Calcium-fortified foods. Look for calcium-fortified orange juice, soy or rice milk, breads, and cereal. Beans. ... vegetables, broccoli, chickpeas, and calcium-fortified products, including orange juice, soy and rice drinks, and cereals. Other Considerations ...

  5. Calcium

    MedlinePLUS

    ... stomach acid (a condition more common in people older than 50) absorb calcium citrate more easily than calcium carbonate. Other forms of calcium in supplements and fortified foods include gluconate, lactate, and phosphate. Calcium absorption is best when a person consumes no more than 500 mg at one ...

  6. Autumn Application of Foliar Urea Alters Winter Storage and Nitrogen Uptake and Growth of Container-Grown Rhododendron and Azalea the Following Spring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One-year-old liners of rhododendron (Rhododendron 'H-1 P.J.M.') and azalea (Rhododendron 'Cannon's Double') grown at different N fertilization rates were used to assess the influence of foliar urea application in the autumn and soil nitrogen (N) applications during the growing season on N storage, N...

  7. Rate of Nitrogen Application during the Growing Season Alters Response of Container-Grown Rhododendron and Azalea to Foliar Urea in Autumn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One-year-old liners of rhododendron (Rhododendron ‘H-1 P.J.M’) and azalea (Rhododendron ‘Cannon’s Double’) grown at different N fertilization rates were used to assess the influence of foliar urea application in the autumn and soil nitrogen (N) applications during the growing season on N storage, N ...

  8. Calcium

    MedlinePLUS

    ... body than any other mineral. Calcium has many important jobs. The body stores more than 99 percent ... send messages through the nervous system. It is important to get plenty of calcium in the foods ...

  9. Calcium

    MedlinePLUS

    Calcium is a mineral that is an essential part of bones and teeth. The heart, nerves, and blood-clotting systems also need calcium ... as well as the calcium-enriched citrus juices, mineral water, canned fish with bones, and soy products ...

  10. Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays

    PubMed Central

    Trouvelot, Sophie; Héloir, Marie-Claire; Poinssot, Benoît; Gauthier, Adrien; Paris, Franck; Guillier, Christelle; Combier, Maud; Trdá, Lucie; Daire, Xavier; Adrian, Marielle

    2014-01-01

    Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of “PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type” oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as signaling molecules, especially in plant microbe interactions, is also presented. Secondly, the potentialities and limits of foliar sprays of carbohydrates to stimulate plant immunity for crop protection against diseases are discussed, with focus on the roles of the leaf cuticle and phyllosphere microflora. PMID:25408694

  11. Pepper plants growth, yield, photosynthetic pigments, and total phenols as affected by foliar application of potassium under different salinity irrigation water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation with high salinity water influences plant growth, production of photosynthetic pigments and total phenols, leading to reduction in crop yield and quality. Foliar application of macro- and/or micro-nutrients can, to some extent, mitigate negative effects of high salinity irrigation water o...

  12. Soybean seed phenol, lignin, and isoflavones and sugars composition are altered by Foliar Boron application in soybean under water stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research showed that foliar boron (B) fertilizer at flowering or seed-fill growth stages altered seed protein, oil, and fatty acids. The objective of this research was to investigate the effects of foliar B fertilizer on seed phenolics (phenol, lignin, and isoflavones) and sugars concentrat...

  13. First evidence on phloem transport of nanoscale calcium oxide in groundnut using solution culture technique

    NASA Astrophysics Data System (ADS)

    Deepa, Manchala; Sudhakar, Palagiri; Nagamadhuri, Kandula Venkata; Balakrishna Reddy, Kota; Giridhara Krishna, Thimmavajjula; Prasad, Tollamadugu Naga Venkata Krishna Vara

    2015-06-01

    Nanoscale materials, whose size typically falls below 100 nm, exhibit novel chemical, physical and biological properties which are different from their bulk counterparts. In the present investigation, we demonstrated that nanoscale calcium oxide particles (n-CaO) could transport through phloem tissue of groundnut unlike the corresponding bulk materials. n-CaO particles are prepared using sol-gel method. The size of the as prepared n-CaO measured (69.9 nm) using transmission electron microscopic technique (TEM). Results of the hydroponics experiment using solution culture technique revealed that foliar application of n-CaO at different concentrations (10, 50, 100, 500, 1,000 ppm) on groundnut plants confirmed the entry of calcium into leaves and stems through phloem compared to bulk source of calcium sprayed (CaO and CaNO3). After spraying of n-CaO, calcium content in roots, shoots and leaves significantly increased. Based on visual scoring of calcium deficiency correction and calcium content in plant parts, we may establish the fact that nanoscale calcium oxide particles (size 69.9 nm) could move through phloem tissue in groundnut. This is the first report on phloem transport of nanoscale calcium oxide particles in plants and this result points to the use of nanoscale calcium oxide particles as calcium source to the plants through foliar application, agricultural crops in particular, as bulk calcium application through foliar nutrition is restricted due to its non-mobility in phloem.

  14. Water Stress and Foliar Boron Application Altered Cell Wall Boron and Seed Nutrition in Near-Isogenic Cotton Lines Expressing Fuzzy and Fuzzless Seed Phenotypes.

    PubMed

    Bellaloui, Nacer; Turley, Rickie B; Stetina, Salliana R

    2015-01-01

    Our previous research, conducted under well-watered conditions without fertilizer application, showed that fuzziness cottonseed trait resulted in cottonseed nutrition differences between fuzzy (F) and fuzzless (N) cottonseed. Under water stress conditions, B mobility is further limited, inhibiting B movement within the plant, affecting seed nutrition (quality). Therefore, we hypothesized that both foliar B and water stress can affect B mobility, altering cottonseed protein, oil, and mineral nutrition. The objective of the current research was to evaluate the effects of the fuzziness seed trait on boron (B) and seed nutrition under water stress and foliar B application using near-isogenic cotton lines (NILs) grown in a repeated greenhouse experiment. Plants were grown under-well watered conditions (The soil water potential was kept between -15 to -20 kPa, considered field capacity) and water stress conditions (soil water potential between -100 and -150 kPa, stressed conditions). Foliar B was applied at a rate of 1.8 kg B ha(-1) as H3BO3. Under well-watered conditions without B the concentrations of seed oil in N lines were higher than in F lines, and seed K and N levels were lower in N lines than in F lines. Concentrations of K, N, and B in leaves were higher in N lines than in F lines, opposing the trend in seeds. Water-stress resulted in higher seed protein concentrations, and the contribution of cell wall (structural) B to the total B exceeded 90%, supporting the structural role of B in plants. Foliar B application under well-watered conditions resulted in higher seed protein, oil, C, N, and B in only some lines. This research showed that cottonseed nutrition differences can occur due to seed fuzziness trait, and water stress and foliar B application can alter cottonseed nutrition. PMID:26098564

  15. Water Stress and Foliar Boron Application Altered Cell Wall Boron and Seed Nutrition in Near-Isogenic Cotton Lines Expressing Fuzzy and Fuzzless Seed Phenotypes

    PubMed Central

    2015-01-01

    Our previous research, conducted under well-watered conditions without fertilizer application, showed that fuzziness cottonseed trait resulted in cottonseed nutrition differences between fuzzy (F) and fuzzless (N) cottonseed. Under water stress conditions, B mobility is further limited, inhibiting B movement within the plant, affecting seed nutrition (quality). Therefore, we hypothesized that both foliar B and water stress can affect B mobility, altering cottonseed protein, oil, and mineral nutrition. The objective of the current research was to evaluate the effects of the fuzziness seed trait on boron (B) and seed nutrition under water stress and foliar B application using near-isogenic cotton lines (NILs) grown in a repeated greenhouse experiment. Plants were grown under-well watered conditions (The soil water potential was kept between -15 to -20 kPa, considered field capacity) and water stress conditions (soil water potential between -100 and -150 kPa, stressed conditions). Foliar B was applied at a rate of 1.8 kg B ha-1 as H3BO3. Under well-watered conditions without B the concentrations of seed oil in N lines were higher than in F lines, and seed K and N levels were lower in N lines than in F lines. Concentrations of K, N, and B in leaves were higher in N lines than in F lines, opposing the trend in seeds. Water-stress resulted in higher seed protein concentrations, and the contribution of cell wall (structural) B to the total B exceeded 90%, supporting the structural role of B in plants. Foliar B application under well-watered conditions resulted in higher seed protein, oil, C, N, and B in only some lines. This research showed that cottonseed nutrition differences can occur due to seed fuzziness trait, and water stress and foliar B application can alter cottonseed nutrition. PMID:26098564

  16. Biomineralization of calcium carbonates and their engineered applications: a review

    PubMed Central

    Dhami, Navdeep K.; Reddy, M. Sudhakara; Mukherjee, Abhijit

    2013-01-01

    Microbially induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process in which microbes produce inorganic materials as part of their basic metabolic activities. This technology has been widely explored and promising with potential in various technical applications. In the present review, the detailed mechanism of production of calcium carbonate biominerals by ureolytic bacteria has been discussed along with role of bacteria and the sectors where these biominerals are being used. The applications of bacterially produced carbonate biominerals for improving the durability of buildings, remediation of environment (water and soil), sequestration of atmospheric CO2 filler material in rubbers and plastics etc. are discussed. The study also sheds light on benefits of bacterial biominerals over traditional agents and also the issues that lie in the path of successful commercialization of the technology of microbially induced calcium carbonate precipitation from lab to field scale. PMID:24194735

  17. Foliar application of ?-D-glucan nanoparticles to control rhizome rot disease of turmeric.

    PubMed

    Anusuya, Sathiyanarayanan; Sathiyabama, Muthukrishnan

    2015-01-01

    The soilborne Oomycete Pythium aphanidermatum is the causal agent of rhizome rot disease, one of the most serious threats to turmeric crops. At present, effective fungicides are not available. Researches on nanoparticles in a number of crops have evidenced the positive changes in gene expression indicating their potential use in crop improvement. Hence, experiments were carried out to determine the effect of ?-D-glucan nanoparticles (nanobiopolymer) in protection of turmeric plants against rot disease by the way of products that reinforce plant's own defense mechanism. Foliar spray of ?-D-glucan nanoparticles (0.1%, w/v) elicited marked increase in the activity of defense enzymes such as peroxidases (E.C.1.11.1.7), polyphenol oxidases (E.C.1.14.18.1), protease inhibitors (E.C.3.4.21.1) and ?-1,3-glucanases (E.C.3.2.1.39) at various age levels. Constitutive and induced isoforms of these enzymes were investigated during this time-course study. ?-D-glucan nanoparticles (GNPs) significantly reduced the rot incidence offering 77% protection. Increased activities of defense enzymes in GNPs-applied turmeric plants may play a role in restricting the development of disease symptoms. These results demonstrated that GNPs could be used as an effective resistance activator in turmeric for control of rhizome rot disease. PMID:25450542

  18. Application of glycerol as a foliar spray activates the defence response and enhances disease resistance of Theobroma cacao.

    PubMed

    Zhang, Yufan; Smith, Philip; Maximova, Siela N; Guiltinan, Mark J

    2015-01-01

    Previous work has implicated glycerol-3-phosphate (G3P) as a mobile inducer of systemic immunity in plants. We tested the hypothesis that the exogenous application of glycerol as a foliar spray might enhance the disease resistance of Theobroma cacao through the modulation of endogenous G3P levels. We found that exogenous application of glycerol to cacao leaves over a period of 4 days increased the endogenous level of G3P and decreased the level of oleic acid (18:1). Reactive oxygen species (ROS) were produced (a marker of defence activation) and the expression of many pathogenesis-related genes was induced. Notably, the effects of glycerol application on G3P and 18:1 fatty acid content, and gene expression levels, in cacao leaves were dosage dependent. A 100?mm glycerol spray application was sufficient to stimulate the defence response without causing any observable damage, and resulted in a significantly decreased lesion formation by the cacao pathogen Phytophthora capsici; however, a 500?mm glycerol treatment led to chlorosis and cell death. The effects of glycerol treatment on the level of 18:1 and ROS were constrained to the locally treated leaves without affecting distal tissues. The mechanism of the glycerol-mediated defence response in cacao and its potential use as part of a sustainable farming system are discussed. PMID:24863347

  19. Root biomass response to foliar application of imazapyr for two imidazolinone tolerant alleles of sunflower (Helianthus annuus L.).

    PubMed

    Sala, Carlos A; Bulos, Mariano; Altieri, Emiliano; Ramos, Mara Laura

    2012-09-01

    Imisun and CLPlus are two imidazolinone tolerance traits in sunflower (Helianthus annuus L.) determined by the expression of two alleles at the locus Ahasl1. Both traits differed in their tolerance level to imazapyr -a type of imidazolinone herbicide- when aboveground biomass is considered, but the concomitant herbicide effect over the root system has not been reported. The objective of this work was to quantify the root biomass response to increased doses of imazapyr in susceptible (ahasl1/ahasl1), Imisun (Ahasl1-1/Ahasl1-1) and CLPlus (Ahasl1-3/Ahasl1-3) homozygous sunflower genotypes. These materials were sprayed at the V2-V4 stage with increased doses of imazapyr (from 0 to 480 g active ingredient ha(-1)) and 14 days after treatment root biomass of each plant was assessed. Genotype at the Ahasl1 locus, dose of imazapyr and their interaction significantly contributed (P < 0.001) to explain the reduction in root biomass accumulation after herbicide application. Estimated dose of imazapyr required to reduce root biomass accumulation by fifty percent (GR(50)) differed statistically for the three genotypes under study (P < 0.001). CLPlus genotypes showed the highest values of GR(50), 300 times higher on average than the susceptible genotypes, and almost 8 times higher than Imisun materials, demonstrating that both alleles differ in their root biomass response to foliar application of increased doses of imazapyr. PMID:23226083

  20. Root biomass response to foliar application of imazapyr for two imidazolinone tolerant alleles of sunflower (Helianthus annuus L.)

    PubMed Central

    Sala, Carlos A.; Bulos, Mariano; Altieri, Emiliano; Ramos, Mara Laura

    2012-01-01

    Imisun and CLPlus are two imidazolinone tolerance traits in sunflower (Helianthus annuus L.) determined by the expression of two alleles at the locus Ahasl1. Both traits differed in their tolerance level to imazapyr a type of imidazolinone herbicide when aboveground biomass is considered, but the concomitant herbicide effect over the root system has not been reported. The objective of this work was to quantify the root biomass response to increased doses of imazapyr in susceptible (ahasl1/ahasl1), Imisun (Ahasl1-1/Ahasl1-1) and CLPlus (Ahasl1-3/Ahasl1-3) homozygous sunflower genotypes. These materials were sprayed at the V2V4 stage with increased doses of imazapyr (from 0 to 480 g active ingredient ha?1) and 14 days after treatment root biomass of each plant was assessed. Genotype at the Ahasl1 locus, dose of imazapyr and their interaction significantly contributed (P < 0.001) to explain the reduction in root biomass accumulation after herbicide application. Estimated dose of imazapyr required to reduce root biomass accumulation by fifty percent (GR50) differed statistically for the three genotypes under study (P < 0.001). CLPlus genotypes showed the highest values of GR50, 300 times higher on average than the susceptible genotypes, and almost 8 times higher than Imisun materials, demonstrating that both alleles differ in their root biomass response to foliar application of increased doses of imazapyr. PMID:23226083

  1. Comparative degradation of [14C]-2,4-dichlorophenoxyacetic acid in wheat and potato after Foliar application and in wheat, radish, lettuce, and apple after soil application.

    PubMed

    Hamburg, A; Puvanesarajah, V; Burnett, T J; Barnekow, D E; Premkumar, N D; Smith, G A

    2001-01-01

    The fate of 2,4-dichlorophenoxyacetic acid (2,4-D) applied foliarly as the 2-ethylhexyl ester (EHE) to wheat and potatoes, to the soil as the dimethylamine (DMA) salt under apple tree canopies, and preplant as the free acid for wheat, lettuce, and radish was studied to evaluate metabolic pathways. Crop fractions analyzed for (14)C residues included wheat forage, straw, and grain; potato vine and tubers; and apple fruit. The primary metabolic pathway for foliar application in wheat is ester hydrolysis followed by the formation of base-labile 2,4-D conjugates. A less significant pathway for 2,4-D in wheat was ring hydroxylation to give NIH-shift products 2,5-dichloro-4-hydroxyphenoxyacetic acid (4-OH-2,5-D), 4-OH-2,3-D, and 5-OH-2,4-D both free and as acid-labile conjugates. The primary metabolic pathway in potato was again ester hydrolysis. 2,4-D acid was further transformed to 4-chlorophenoxyacetic acid and 4-OH-2,5-D. For the soil applications, (14)C residues in the crops were low, and characterization of the (14)C residues indicated association with or incorporation into the biochemical matrix of the tissue. The degradative pathways observed in wheat are similar to those characterized in other intact plant studies but differ from those in studies in wheat cell suspension culture in that no amino acid conjugates were observed. PMID:11170570

  2. Reversible loss of gravitropic sensitivity in maize roots after tip application of calcium chelators

    NASA Technical Reports Server (NTRS)

    Lee, J. S.; Mulkey, T. J.; Evans, M. L.

    1983-01-01

    The application of calcium chelating agents (EDTA or EGTA) to the tips of maize roots caused a loss of gravitropic sensitivity. When the chelator was replaced with calcium chloride, gravitropic sensitivity was restored. Asymmetric application of calcium chloride near the tip of a vertical root caused curvature toward the calcium source. When the calcium was applied to the upper surface of the tip of a root oriented horizontally, the root curved upward even though control roots exhibited strong downward curvature. Application of calcium chloride to the tips of decapped roots, which are known to be gravitropically insensitive, did not restore gravitropic sensitivity. However, asymmetric application of calcium chloride near the tips of decapped roots caused curvature toward the calcium source. Calcium may play a key role in linking gravity detection to gravitropic curvature in roots.

  3. Study of the effects of proline, phenylalanine, and urea foliar application to Tempranillo vineyards on grape amino acid content. Comparison with commercial nitrogen fertilisers.

    PubMed

    Garde-Cerdn, T; Lpez, R; Portu, J; Gonzlez-Arenzana, L; Lpez-Alfaro, I; Santamara, P

    2014-11-15

    The aim of this work was to study the influence of foliar application of different nitrogen sources on grape amino acid content. The nitrogen sources applied to Tempranillo grapevines were proline, phenylalanine, urea, and two commercial nitrogen fertilisers, both without and with amino acids in their formulations. All treatments were applied at veraison and one week later. Proline treatment did not affect the must nitrogen composition. However, phenylalanine and urea foliar application enhanced the plants' synthesis of most of the amino acids, producing similar effects. In addition, the spray of commercial nitrogen fertilisers over leaves also induced a rise in grape amino acid concentrations regardless of the presence or absence of amino acids in their formulation. The most effective treatments were phenylalanine and urea followed by nitrogen fertilisers. This finding is of oenological interest for improved must nitrogen composition, ensuring better fermentation kinetics and most likely enhancing wine quality. PMID:24912708

  4. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium chloride production subcategory. 415.40 Section 415.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory. The provisions of this subpart are applicable to...

  5. 40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium carbide furnaces subcategory. 424.50 Section 424.50 Protection of Environment ENVIRONMENTAL... CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory. The provisions of this subpart are applicable to...

  6. 40 CFR 415.300 - Applicability; description of the calcium carbonate production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium carbonate production subcategory. 415.300 Section 415.300 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory. The provisions of this subpart are applicable to...

  7. 40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium carbide furnaces subcategory. 424.50 Section 424.50 Protection of Environment ENVIRONMENTAL... CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory. The provisions of this subpart are applicable to...

  8. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium chloride production subcategory. 415.40 Section 415.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory. The provisions of this subpart are applicable to...

  9. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium chloride production subcategory. 415.40 Section 415.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory. The provisions of this subpart are applicable to...

  10. 40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to...

  11. 40 CFR 415.300 - Applicability; description of the calcium carbonate production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium carbonate production subcategory. 415.300 Section 415.300 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory. The provisions of this subpart are applicable to...

  12. 40 CFR 415.300 - Applicability; description of the calcium carbonate production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium carbonate production subcategory. 415.300 Section 415.300 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory. The provisions of this subpart are applicable to...

  13. 40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... other calcium carbide furnaces subcategory. 424.50 Section 424.50 Protection of Environment... SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory. The provisions of this subpart are applicable to...

  14. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium chloride production subcategory. 415.40 Section 415.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory. The provisions of this subpart are applicable to...

  15. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium chloride production subcategory. 415.40 Section 415.40 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory. The provisions of this subpart are applicable to...

  16. 40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to...

  17. 40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium carbide furnaces subcategory. 424.50 Section 424.50 Protection of Environment ENVIRONMENTAL... CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory. The provisions of this subpart are applicable to...

  18. 40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to...

  19. 40 CFR 424.50 - Applicability; description of the other calcium carbide furnaces subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium carbide furnaces subcategory. 424.50 Section 424.50 Protection of Environment ENVIRONMENTAL... CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory. The provisions of this subpart are applicable to...

  20. 40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to...

  1. 40 CFR 415.310 - Applicability; description of the calcium hydroxide production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium hydroxide production subcategory. 415.310 Section 415.310 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory. The provisions of this subpart are applicable to...

  2. 40 CFR 415.300 - Applicability; description of the calcium carbonate production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium carbonate production subcategory. 415.300 Section 415.300 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory. The provisions of this subpart are applicable to...

  3. 40 CFR 415.300 - Applicability; description of the calcium carbonate production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium carbonate production subcategory. 415.300 Section 415.300 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory. The provisions of this subpart are applicable to...

  4. Nontarget effects of foliar fungicide application on the rhizosphere: diversity of nifH gene and nodulation in chickpea field

    PubMed Central

    Yang, C; Hamel, C; Vujanovic, V; Gan, Y

    2012-01-01

    Aims This study explores nontarget effects of fungicide application on field-grown chickpea. Methods and Results Molecular methods were used to test the effects of foliar application of fungicide on the diversity and distribution of nifH genes associated with two chickpea cultivars and their nodulation. Treatments were replicated four times in a split-plot design in the field, in 2008 and 2009. Chemical disease control did not change the richness of the nifH genes associated with chickpea, but selected different dominant nifH gene sequences in 2008, as revealed by correspondence analysis. Disease control strategies had no significant effect on disease severity or nifH gene distribution in 2009. Dry weather conditions rather than disease restricted plant growth that year, suggesting that reduced infection rather than the fungicide is the factor modifying the distribution of nifH gene in chickpea rhizosphere. Reduced nodule size and enhanced N2-fixation in protected plants indicate that disease control affects plant physiology, which may in turn influence rhizosphere bacteria. The genotypes of chickpea also affected the diversity of the nifH gene in the rhizosphere, illustrating the importance of plant selective effects on bacterial communities. Conclusions We conclude that the chemical disease control affects nodulation and the diversity of nifH gene in chickpea rhizosphere, by modifying host plant physiology. A direct effect of fungicide on the bacteria cannot be ruled out, however, as residual amounts of fungicide were found to accumulate in the rhizosphere soil of protected plants. Significance and Impact of the Study Systemic nontarget effect of phytoprotection on nifH gene diversity in chickpea rhizosphere is reported for the first time. This result suggests the possibility of manipulating associative biological nitrogen fixation in the field. PMID:22335393

  5. Calcium

    MedlinePLUS

    ... But your parents were right to make you drink milk when you were little. It's loaded with calcium, a mineral vital for building strong bones and teeth. Why Do I Need ... who smoke or drink soda, caffeinated beverages, or alcohol may get even ...

  6. Amorphous calcium phosphate and its application in dentistry

    PubMed Central

    2011-01-01

    Amorphous Calcium Phosphate (ACP) is an essential mineral phase formed in mineralized tissues and the first commercial product as artificial hydroxyapatite. ACP is unique among all forms of calcium phosphates in that it lacks long-range, periodic atomic scale order of crystalline calcium phosphates. The X-ray diffraction pattern is broad and diffuse with a maximum at 25 degree 2 theta, and no other different features compared with well-crystallized hydroxyapatite. Under electron microscopy, its morphological form is shown as small spheroidal particles in the scale of tenths nanometer. In aqueous media, ACP is easily transformed into crystalline phases such as octacalcium phosphate and apatite due to the growing of microcrystalline. It has been demonstrated that ACP has better osteoconductivity and biodegradability than tricalcium phosphate and hydroxyapatite in vivo. Moreover, it can increase alkaline phosphatase activities of mesoblasts, enhance cell proliferation and promote cell adhesion. The unique role of ACP during the formation of mineralized tissues makes it a promising candidate material for tissue repair and regeneration. ACP may also be a potential remineralizing agent in dental applications. Recently developed ACP-filled bioactive composites are believed to be effective anti-demineralizing/remineralizing agents for the preservation and repair of tooth structures. This review provides an overview of the development, structure, chemical composition, morphological characterization, phase transformation and biomedical application of ACP in dentistry. PMID:21740535

  7. Foliar application of isopyrazam and epoxiconazole improves photosystem II efficiency, biomass and yield in winter wheat.

    PubMed

    Ajigboye, Olubukola O; Murchie, Erik; Ray, Rumiana V

    2014-09-01

    A range of fungicides including epoxiconazole, azoxystrobin and isopyrazam, were applied to winter wheat at GS 31/32 to determine their effect on photosystem II (PSII) efficiency, biomass and yield. Frequent, repeated measurements of chlorophyll fluorescence were carried on plants grown under different water regimes in controlled environment and in the field to establish the transiency of fluorescence changes in relation to fungicide application. Application of the succinate dehydrogenase inhibitor isopyrazam in a mixture with the triazole epoxiconazole increased PSII efficiency associated with a 28% increase in biomass in the controlled environment and 4% increase in grain yield in the field in the absence of disease pressure. Application of isopyrazam and epoxiconazole increased efficiency of PSII photochemistry (Fv'/Fm') as early as 4h following application associated with improved photosynthetic gas exchange and increased rates of electron transport. We reveal a strong, positive relationship between Fv'/Fm' and CO2 assimilation rate, stomatal conductance and transpiration rate in controlled environment and Fv'/Fm' detected just after anthesis on the flag leaf at GS 73 and grain yield in field. We conclude that application of a specific combination of fungicides with positive effects of plant physiology in the absence of disease pressure results in enhanced biomass and yield in winter wheat. Additionally, an accurate and frequent assessment of photosynthetic efficiency of winter wheat plants can be used to predict yield and biomass in the field. PMID:25175650

  8. Investigating calcium polyphosphate addition to a conventional calcium phosphate cement for bone-interfacing applications

    NASA Astrophysics Data System (ADS)

    Krausher, Jennifer Lynn

    Calcium phosphate cements (CPCs) are of great interest in bone regeneration applications because of their biocompatibility and osteoconductivity, and as delivery vehicles for therapeutics; however, delivery applications have been limited by adverse interactions between therapeutics and the cement setting reaction. Amorphous calcium polyphosphate (CPP) yields a biodegradable material with a demonstrated drug delivery capacity following appropriate processing. The incorporation of drug-loaded CPP into a CPC is under consideration as a method of minimizing adverse interactions and extending drug release. This thesis represents the first investigation into the effects of CPP addition on the properties, setting and antibiotic release profile of a conventional apatitic calcium phosphate cement. As-made, gelled and vancomycin-loaded CPP particulate were added to the powder component of a conventional dicalcium phosphate/tetracalcium phosphate CPC. The setting behaviour, set properties and microstructure of the resulting CPP-CPCs were evaluated with setting time testing (Gilmore needle method), pH testing, mechanical testing, SEM imaging, XRD and FTIR analysis. In vitro degradation and elution behaviour were evaluated by monitoring calcium release (atomic absorbance spectroscopy), mechanical strength and vancomycin release (UV-visual spectrophotometry). CPP addition was found to increase the setting time, reduce the mechanical strength and inhibit the conversion of the CPC starting powders to the set apatitic phase. The most likely mechanism for the observed effect of CPP addition was the adsorption of polyphosphate chains on the particle surfaces, which would inhibit the dissolution of the starting powders and the conversion of apatite precursor phases to apatite, leading to reduced mechanical properties. The detrimental effects of CPP were reduced by limiting the CPP fraction to less than a few weight per cent and increasing the size of the CPP particulate. CPP-containing CPCs were found to degrade more rapidly than the CPP-free controls. The ability of drug-loaded CPP to minimize adverse interactions between drug and cement could not be determined because of the adverse effect of CPP itself and the low vancomycin loads studied, but there was evidence that vancomycin release from apatitic CPCs could be extended through the use of loaded CPP.

  9. Foliar application of plant growth-promoting bacteria and humic acid increase maize yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant growth promoter bacteria (PGPB) can be used to reduce fertilizer inputs to crops. Seed inoculation is the main method of PGPB application, but competition with rhizosphere microorganisms reduces their effectiveness. Here we propose a new biotechnological tool for plant stimulation using endoph...

  10. Influence of phosphorus application and arbuscular mycorrhizal inoculation on growth, foliar nitrogen mobilization, and phosphorus partitioning in cowpea plants.

    PubMed

    Taffouo, Victor Dsir; Ngwene, Benard; Akoa, Amougou; Franken, Philipp

    2014-07-01

    The present study was undertaken to evaluate the effects of phosphorus (P) application and arbuscular mycorrhizal (AM) fungi (Funneliformis mosseae) on growth, foliar nitrogen mobilization, and phosphorus partitioning in cowpea (Vigna unguiculata cv. Vita-5) plants. The experiment was conducted in a greenhouse in pots containing a mixture of vermiculite and sterilized quartz sand. Mycorrhizal and non-mycorrhizal cowpea plants were supplied with three levels of soluble P (0.1 (low P), 0.5 (medium P), or 1.0 mM (high P)).Cowpea plants supplied with low P fertilization showed significantly (p?

  11. Ex Vivo Application of Secreted Metabolites Produced by Soil-Inhabiting Bacillus spp. Efficiently Controls Foliar Diseases Caused by Alternaria spp.

    PubMed

    Ali, Gul Shad; El-Sayed, Ashraf S A; Patel, Jaimin S; Green, Kari B; Ali, Mohammad; Brennan, Mary; Norman, David

    2015-01-01

    Bacterial biological control agents (BCAs) are largely used as live products to control plant pathogens. However, due to variable environmental and ecological factors, live BCAs usually fail to produce desirable results against foliar pathogens. In this study, we investigated the potential of cell-free culture filtrates of 12 different bacterial BCAs isolated from flower beds for controlling foliar diseases caused by Alternaria spp. In vitro studies showed that culture filtrates from two isolates belonging to Bacillus subtilis and Bacillus amyloliquefaciens displayed strong efficacy and potencies against Alternaria spp. The antimicrobial activity of the culture filtrate of these two biological control agents was effective over a wider range of pH (3.0 to 9.0) and was not affected by autoclaving or proteolysis. Comparative liquid chromatography-mass spectrometry (LC-MS) analyses showed that a complex mixture of cyclic lipopeptides, primarily of the fengycin A and fengycin B families, was significantly higher in these two BCAs than inactive Bacillus spp. Interaction studies with mixtures of culture filtrates of these two species revealed additive activity, suggesting that they produce similar products, which was confirmed by LC-tandem MS analyses. In in planta pre- and postinoculation trials, foliar application of culture filtrates of B. subtilis reduced lesion sizes and lesion frequencies caused by Alternaria alternata by 68 to 81%. Taken together, our studies suggest that instead of live bacteria, culture filtrates of B. subtilis and B. amyloliquefaciens can be applied either individually or in combination for controlling foliar diseases caused by Alternaria species. PMID:26519395

  12. 40 CFR 461.20 - Applicability; description of the calcium subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... calcium subcategory. 461.20 Section 461.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart applies to...

  13. 40 CFR 461.20 - Applicability; description of the calcium subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... calcium subcategory. 461.20 Section 461.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS BATTERY MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart applies to discharges...

  14. 40 CFR 461.20 - Applicability; description of the calcium subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... calcium subcategory. 461.20 Section 461.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart applies to...

  15. 40 CFR 461.20 - Applicability; description of the calcium subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... calcium subcategory. 461.20 Section 461.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS BATTERY MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart applies to discharges...

  16. 40 CFR 461.20 - Applicability; description of the calcium subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... calcium subcategory. 461.20 Section 461.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) BATTERY MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart applies to...

  17. Enhancing growth, phytochemical constituents and aphid resistance capacity in cabbage with foliar application of eckol - a biologically active phenolic molecule from brown seaweed.

    PubMed

    Rengasamy, Kannan R R; Kulkarni, Manoj G; Pendota, Srinivasa C; Van Staden, Johannes

    2016-03-25

    Although foliar application of seaweed extracts on plant growth and development has and is extensively studied, reliable knowledge and understanding of the mode of action of particular compound(s) responsible for enhancing plant growth is lacking. A brown seaweed Ecklonia maxima is widely used commercially as a biostimulant to improve plant growth and crop protection. Eckol, a phenolic compound isolated from E. maxima has recently shown stimulatory effects in maize, indicating its potential use as a plant biostimulant. Cabbage is a widely cultivated vegetable crop throughout the world, which requires high input of fertilizers and is susceptible to several aphid borne diseases. This study was conducted to evaluate the effect of foliar application of eckol on the growth, phytochemical constituents and myrosinase activity (aphid resistance capacity) of commercially cultivated cabbage. Foliar application of eckol (10(-6)M) significantly enhanced shoot and root length, shoot and root fresh and dry weight, leaf area and leaf number. This treatment also showed a significant increase in photosynthetic pigments (chlorophyll 'a', chlorophyll 'b', total chlorophyll and carotenoid) compared to the untreated plants. The levels of protein, proline and iridoid glycosides were significantly higher in cabbage leaves with eckol treatment. All the control plants were severely infested with cabbage aphid (Brevicoryne brassicae) but no infestation was observed on the eckol-sprayed plants, which can be attributed to an increase in myrosinase activity. This study reveals dual effects (plant growth promoting and insect repelling) of eckol on cabbage plants that need further investigations both under field conditions and in other brassicaceous species. PMID:26585339

  18. Foliar Temperature Gradients as Drivers of Budburst in Douglas-fir: New Applications of Thermal Infrared Imagery

    NASA Astrophysics Data System (ADS)

    Miller, R.; Lintz, H. E.; Thomas, C. K.; Salino-Hugg, M. J.; Niemeier, J. J.; Kruger, A.

    2014-12-01

    Budburst, the initiation of annual growth in plants, is sensitive to climate and is used to monitor physiological responses to climate change. Accurately forecasting budburst response to these changes demands an understanding of the drivers of budburst. Current research and predictive models focus on population or landscape-level drivers, yet fundamental questions regarding drivers of budburst diversity within an individual tree remain unanswered. We hypothesize that foliar temperature, an important physiological property, may be a dominant driver of differences in the timing of budburst within a single tree. Studying these differences facilitates development of high throughput phenotyping technology used to improve predictive budburst models. We present spatial and temporal variation in foliar temperature as a function of physical drivers culminating in a single-tree budburst model based on foliar temperature. We use a novel remote sensing approach, combined with on-site meteorological measurements, to demonstrate important intra-canopy differences between air and foliar temperature. We mounted a thermal infrared camera within an old-growth canopy at the H.J. Andrews LTER forest and imaged an 8m by 10.6m section of a Douglas-fir crown. Sampling one image per minute, approximately 30,000 thermal infrared images were collected over a one-month period to approximate foliar temperature before, during and after budburst. Using time-lapse photography in the visible spectrum, we documented budburst at fifteen-minute intervals with eight cameras stratified across the thermal infrared camera's field of view. Within the imaged tree's crown, we installed a pyranometer, 2D sonic anemometer and fan-aspirated thermohygrometer and collected 3,000 measurements of net shortwave radiation, wind speed, air temperature and relative humidity. We documented a difference of several days in the timing of budburst across both vertical and horizontal gradients. We also observed clear spatial and temporal foliar temperature gradients. In addition to exploring physical drivers of budburst, this remote sensing approach provides insight into intra-canopy structural complexity and opportunities to advance our understanding of vegetation-atmospheric interactions.

  19. Foliar application of microbial and plant based biostimulants increases growth and potassium uptake in almond (Prunus dulcis [Mill.] D. A. Webb).

    PubMed

    Saa, Sebastian; Olivos-Del Rio, Andres; Castro, Sebastian; Brown, Patrick H

    2015-01-01

    The use of biostimulants has become a common practice in agriculture. However, there is little peer-reviewed research on this topic. In this study we tested, under controlled and replicated conditions, the effect of one biostimulant derived from seaweed extraction (Bio-1) and another biostimulant derived from microbial fermentation (Bio-2). This experiment utilized 2-years-old almond plants over two growing seasons in a randomized complete design with a full 2 × 4 factorial structure with two soil potassium treatments (125 μg g(-1) of K vs. 5 μg g(-1)) and four foliar treatments (No spray, Foliar-K, Bio-1, Bio-2). Rubidium was utilized as a surrogate for short-term potassium uptake and plant growth, nutrient concentration, and final plant biomass were evaluated. There was a substantial positive effect of both biostimulant treatments on total shoot leaf area, and significant increases in shoot length and biomass under adequate soil potassium supply with a positive effect of Bio-1 only under low K supply. Rubidium uptake was increased by Bio-1 application an effect that was greater under the low soil K treatment. Though significant beneficial effects of the biostimulants used on plant growth were observed, it is not possible to determine the mode of action of these materials. The results presented here illustrate the promise and complexity of research involving biostimulants. PMID:25755660

  20. Foliar application of microbial and plant based biostimulants increases growth and potassium uptake in almond (Prunus dulcis [Mill.] D. A. Webb)

    PubMed Central

    Saa, Sebastian; Olivos-Del Rio, Andres; Castro, Sebastian; Brown, Patrick H.

    2015-01-01

    The use of biostimulants has become a common practice in agriculture. However, there is little peer-reviewed research on this topic. In this study we tested, under controlled and replicated conditions, the effect of one biostimulant derived from seaweed extraction (Bio-1) and another biostimulant derived from microbial fermentation (Bio-2). This experiment utilized 2-years-old almond plants over two growing seasons in a randomized complete design with a full 2 × 4 factorial structure with two soil potassium treatments (125 μg g-1 of K vs. 5 μg g-1) and four foliar treatments (No spray, Foliar-K, Bio-1, Bio-2). Rubidium was utilized as a surrogate for short-term potassium uptake and plant growth, nutrient concentration, and final plant biomass were evaluated. There was a substantial positive effect of both biostimulant treatments on total shoot leaf area, and significant increases in shoot length and biomass under adequate soil potassium supply with a positive effect of Bio-1 only under low K supply. Rubidium uptake was increased by Bio-1 application an effect that was greater under the low soil K treatment. Though significant beneficial effects of the biostimulants used on plant growth were observed, it is not possible to determine the mode of action of these materials. The results presented here illustrate the promise and complexity of research involving biostimulants. PMID:25755660

  1. Quantifying the non-fungicidal effects of foliar applications of fluxapyroxad (Xemium) on stomatal conductance, water use efficiency and yield in winter wheat.

    PubMed

    Smith, J; Grimmer, M; Waterhouse, S; Paveley, N

    2013-01-01

    The active ingredient fluxapyroxad belongs to the chemical group of carboxamides and is a new generation succinate dehydrogenase inhibitor (SDHI) in complex II of the mitochondrial respiratory chain. It has strong efficacy against the key foliar diseases of winter wheat in the UK: Septoria leaf blotch, yellow stripe rust and brown rust. Fluxapyroxad is marketed under the brand name of Xemium, was launched in 2012 and is available in the UK as a solo product (Imtrex) for co-application with triazoles, in co-formulation with epoxiconazole (Adexar), or in a three way formulation with epoxiconazole and pyraclostrobin (Ceriax). The objective of the study was to quantify the direct effects of Xemium on stomatal conductance and yield, mediated through stimulation of host physiology. Three field experiments and two controlled environment (CE) experiments were conducted across three cropping seasons (2010-2012) in Herefordshire and Cambridge, in the UK. Xemium was evaluated against boscalid, pyraclostrobin (F500), epoxiconazole and an untreated control. Across site-seasons, disease severity was significantly reduced when Xemium was applied as a foliar spray. Healthy canopy size and duration was increased by Xemium and canopy greening effects were seen shortly after application. Stomatal conductance was found to be consistently lower in Xemium treated plants but reduced stomatal opening was not found to be detrimental to yield in these experiments. Large, beneficial effects of Xemium on water use efficiency were found at the canopy level and this finding was supported by measurements of instantaneous water use efficiency at the leaf level. Effects on season long water use efficiency were largely driven by improvements in yield for a given amount of water uptake. Foliar applications of Xemium reduced the water required to produce 1.0 t grain per hectare by 82,330 L(82 t) when compared with an untreated crop. Yield was significantly higher in Xemium treatments and this was achieved primarily through increases in grains ear. Evidence is presented hereto show that in addition to controlling visible disease symptoms, Xemium is able to exert positive physiological effects on the host. The yield increase from plots treated with Xemium applied at standard commercial timings was shown to exceed that which can be explained solely through good disease control and the associated loss of healthy canopy area. Approximately 1.0 t ha(-1) (12%) yield was produced by Xemium treatments which could not be accounted for through the control of visible disease symptoms. PMID:25151827

  2. Effects of foliar boron application on seed composition, cell wall boron, and seed δ15N and δ13C isotopes in water-stressed soybean plants

    PubMed Central

    Bellaloui, Nacer; Hu, Yanbo; Mengistu, Alemu; Kassem, My A.; Abel, Craig A.

    2013-01-01

    Limited information is available on the effects of foliar boron (B) application on soybean seed composition. The objective of this research was to investigate the effects of foliar B on seed composition (protein, oil, fatty acids, and sugars). Our hypothesis was that since B is involved in nitrogen and carbon metabolism, it may impact seed composition. A repeated greenhouse experiment was conducted where half of the soybean plants was exposed to water stress (WS) and the other half was well-watered. Foliar boron (FB) in the form of boric acid was applied twice at a rate of 1.1 kg ha−1. The first application was during flowering stage, and the second application was during seed-fill stage. Treatments were water stressed plants with no FB (WS–B); water stressed plants with FB (WS+B); watered plants without FB (W–B), and watered plants with FB (W+B). The treatment W–B was used as a control. Comparing with WS–B plants, B concentration was the highest in leaves and seed of W+B plants (84% increase in leaves and 73% in seed). Seeds of W+B plants had higher protein (11% increase), oleic acid (27% increase), sucrose (up to 40% increase), glucose, and fructose comparing with W–B. However, seed stachyose concentrations increased by 43% in WS–B plants seed compared with W–B plants. Cell wall (structural) B concentration in leaves was higher in all plants under water stress, especially in WS–B plants where the percentage of cell wall B reached up to 90%. Water stress changed seed δ15N and δ13C values in both B applied and non-B applied plants, indicating possible effects on nitrogen and carbon metabolism. This research demonstrated that FB increased B accumulation in leaves and seed, and altered seed composition of well-watered and water stressed plants, indicating a possible involvement of B in seed protein, and oleic and linolenic fatty acids. Further research is needed to explain mechanisms of B involvement in seed protein and fatty acids. PMID:23888163

  3. The role of calcium in improving photosynthesis and related physiological and biochemical attributes of spring wheat subjected to simulated acid rain.

    PubMed

    Dolatabadian, Aria; Sanavy, Seyed Ali Mohammad Modarres; Gholamhoseini, Majid; Joghan, Aydin Khodaei; Majdi, Mohammad; Kashkooli, Arman Beyraghdar

    2013-04-01

    The response of photosynthesis parameters, catalase, superoxide dismutase and peroxidase activity, malondialdehyde, proline, chlorophyll, yield and yield components to foliar application of calcium and simulated acid rain in wheat were investigated. Foliar treatment of calcium led to significant increases in the photosynthesis rate, transpiration rate, stomatal conductance, proline, chlorophyll, yield and yield components in plants subjected to acid rain. Antioxidant enzyme activity and lipid peroxidation in the wheat leaves decreased because of calcium foliar application. Calcium hindered degradation of the rubisco subunits under acid rain treatment compared with water-treated plants. Results suggest that acid rain induces the production of free radicals resulting in lipid peroxidation of the cell membrane so that significant increase in antioxidant enzyme activity was observed. In addition, photosynthetic parameters i.e. photosynthesis rate, transpiration rate and stomatal conductance were drastically suppressed by acid rain. The cellular damage caused by free radicals might be reduced or prevented by a protective metabolism including antioxidative enzymes and calcium. We report that foliar application of calcium before acid rain may ameliorate the adverse effects of acid rain in wheat plants. PMID:24431486

  4. Therapeutic Applications of Calcium Metabolism Modulation in Heart Disease.

    PubMed

    Synetos, Andreas; Stathogiannis, Konstantinos; Papanikolaou, Aggelos; Drakopoulou, Maria; Trantalis, George; Kaitozis, Odysseas; Latsios, George; Giannopoulos, George; Deftereos, Spyridon; Toutouzas, Konstantinos; Tousoulis, Dimitrios

    2016-01-01

    Cardiovascular disease is the leading cause of death worldwide and there is extensive research on the pathophysiology of all its clinical entities. Despite the big array of possible therapeutic modalities for cardiovascular disease, there is still a big necessity to develop novel treatments that will augment our strategies for tackling the burden of cardiovascular disease and decrease morbidity and mortality. A major player in both the physiology and pathophysiology of the cardiovascular system is calcium. Extracellular calcium is required in order to initiate cardiac muscle contraction and promote the calcium-induced calcium release mechanism from the sarcoplasmic reticulum. A lot of molecules and structures that in a direct or indirect way interact with calcium are being studied and there is a constant flow of new information that is emerging. In this review we focus on some of these calcium metabolism modulators representatives such as SERCA2a, RyR2, S100A1, phosholamban and calcineurin. We emphasize on their mechanism of action, their role in cardiovascular disease and potential therapeutic implications. We also focus on the effect the bisphosphonates might have in regression of the calcium deposition in the human arteries as well as the usage of novel biomarkers such as mircoRNAs in calcium metabolism modulation in heart disease. PMID:26411599

  5. Effect of foliar application of antitranspirant on photosynthesis and water relations of pepper plants under different levels of CO2 and water stress.

    PubMed

    del Amor, Francisco M; Cuadra-Crespo, Paula; Walker, David J; Cmara, Jos M; Madrid, Ramn

    2010-10-15

    Strategies such as foliar application of antitranspirants have the potential to regulate transpiration, but often, the limitation of CO(2) exchange as a result of reduced stomatal conductance can impair this beneficial effect. Elevated ambient [CO(2)] could significantly improve CO(2) diffusion while effectively reducing transpiration. In this experiment, we examined the response of sweet pepper (Capsicum annuum L.) to the foliar application of antitranspirant (AT) under two [CO(2)] (380 and 2000 micromol mol(-1)) and two drought intensities (4 or 8d without irrigation). The results showed that stomatal conductance and transpiration were reduced, while AT impaired photosynthesis at standard, but not at elevated [CO(2)] of fully irrigated plants. This effect was already apparent after 4d of drought. Drought had a minor impact on chlorophyll fluorescence (F(v)/F(m)). Additionally, root respiration was increased at elevated [CO(2)] but, after 8d of drought, it was higher for plants treated with AT than for non-sprayed plants. Leaf water potential was affected more by drought at ambient compared to elevated [CO(2)], and, especially after 8d of drought, AT minimized the reductions in leaf water potential. Leaf concentrations of proline and starch were affected by both [CO(2)] and AT, especially after 8d of drought. Moreover, increasing [CO(2)] promoted the accumulation of starch, but led to decreases in the tissue concentrations of the soluble organic osmolytes, and hence diminished osmotic adjustment after 8d of water withholding, relative to ambient [CO(2)]. This study indicates that, in addition to the reported beneficial effect of elevated [CO(2)] on drought stress, AT could significantly improve drought tolerance in sweet pepper plants. PMID:20542351

  6. Frequency Encoding in Excitable Systems with Applications to Calcium Oscillations

    NASA Astrophysics Data System (ADS)

    Tang, Yuanhua; Othmer, Hans G.

    1995-08-01

    A number of excitable cell types respond to a constant hormonal stimulus with a periodic oscillation in intracellular calcium. The frequency of oscillation is often proportional to the hormonal stimulus, and one says that the stimulus is frequency encoded. Here we develop a theory of frequency encoding in excitable systems and apply it to intracellular calcium oscillations that result from increases in the intracellular level of inositol 1,4,5-trisphosphate.

  7. Improvement of grape and wine phenolic content by foliar application to grapevine of three different elicitors: Methyl jasmonate, chitosan, and yeast extract.

    PubMed

    Portu, Javier; López, Rosa; Baroja, Elisa; Santamaría, Pilar; Garde-Cerdán, Teresa

    2016-06-15

    Phenolic compounds play a key role in grape and wine organoleptic properties, being therefore a key parameter in wine quality. Elicitor application constitutes an interesting field of research since it is indirectly involved in the accumulation of phenolic compounds. The aim of this study was to compare the effect of the application of three different elicitors on both grape and wine phenolic content. Methyl jasmonate, chitosan, and a commercial yeast extract were applied to the canopy at veraison and one week later. Results showed that foliar treatments carried out with methyl jasmonate and yeast extract achieved the best results, increasing grape and wine anthocyanin content when compared to the control. Moreover, the application of the yeast elicitor also enhanced grape stilbene content. In contrast, the chitosan treatment did not have a substantial impact on the phenolic compounds. The results of this study indicate that methyl jasmonate and yeast extract applications could be a simple practice to increase grape and wine phenolic content. PMID:26868568

  8. PHYSIOLOGY AND YIELD RESPONSES OF COTTON TO FOLIAR UREA WITH NBPT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Urea is the most recommended foliar N source, due to its relatively low toxicity, quick absorption, and low cost. However, in the literature reports of yield increments with foliar urea application are not consistent. The objectives of this research were to study foliar urea assimilation in cotton...

  9. Effects of atmospheric CO{sub 2} enrichment and foliar methanol application on net photosynthesis of sour orange tree (Citrus Aurantium; Rutaceae) leaves

    SciTech Connect

    Idso, S.B.; Garcia, R.L.; Kimball, B.A.; Idso, K.E.; Hoober, J.K.

    1995-01-01

    Foliar spray applications of 40% aqueous methanol were made to sunlit leaves of sour orange trees that had been grown continuously in clear-plastic-wall open-top enclosures maintained out-of-doors at Phoenix, Arizona, for over 5.5 years in ambient air of approximately 400 {mu}mol mol{sup -1} CO{sub 2} and in air enriched with CO{sub 2} to a concentration of approximately 700 {mu}mol mol{sup -1}. No unambiguous effects of the methanol applications were detected in photosynthesis measurements made on foliage in either of the two CO{sub 2} treatments. THe 75% increase in CO{sub 2}, however, raised the upper-limiting leaf temperature for positive net photosynthesis by approximately 7 C, which resulted in a 75% enhancement in net photosynthesis at a leaf temperature of 31 C, a 100% enhancement at a leaf temperature of 35 C, and a 200% enhancement at 42 C. 13 refs., 2 figs., 1 tab.

  10. Calcium Deficient Hydroxyapatite for Medical Application Prepared by Hydrothermal Method

    NASA Astrophysics Data System (ADS)

    Ioku, Koji; Kamitakahara, Masanobu; Ikeda, Tohru

    2010-11-01

    Hydrothermal processing plays a key role in the synthesis of biomaterials with excellent biocompatibility in the physiological environment. Especially, calcium phosphates are paid to much attention for the regenerative medicine. Two kinds of porous materials of hydroxyapatite with 70% porosity were prepared. One of them is a newly developed calcium-deficient hydroxyapatite composed of rod-shaped particles of about 20 ?m in length synthesized hydrothermally (HHA) and the other one is the stoichiometric hydroxyapatite (SHA) prepared by the conventional sintering method. These materials were used for animal implantation tests to compare these biological responses. In the rabbit femur, implanted HHA was slowly resorbed and then most of the implanted HHA was resorbed after 72 weeks. The implanted SHA was unresorbed throughout the experimental period. The volume of newly formed bone and the number of osteoclasts in the implanted region were significantly larger in HHA than in SHA after 24 weeks. Results in the present research suggested that the activity of osteoclasts correlated to the bone forming activity of osteoblasts. The method to synthesize biodegradable pure calcium-deficient HA is expected to provide adequate biodegradability and bone replaceability.

  11. Accumulation of Glycoconjugates of 3-Methyl-4-hydroxyoctanoic Acid in Fruits, Leaves, and Shoots of Vitis vinifera cv. Monastrell following Foliar Applications of Oak Extract or Oak Lactone.

    PubMed

    Pardo-Garcia, Ana I; Wilkinson, Kerry L; Culbert, Julie A; Lloyd, Natoiya D R; Alonso, Gonzalo L; Salinas, M Rosario

    2015-05-13

    Grapevines are capable of absorbing volatile compounds present in the vineyard during the growing season, and in some cases, volatiles have been found to accumulate in fruits or leaves in glycoconjugate forms, that is, with one or more sugar moieties attached. The presence of oak lactone in wine is usually attributable to oak maturation, but oak lactone has been detected in wines made with fruit from grapevines treated with oak extract or oak lactone. This study investigated the accumulation of glycoconjugates of 3-methyl-4-hydroxyoctanoic acid (i.e., the ring-opened form of oak lactone) in the fruits, leaves, and shoots of Monastrell grapevines following foliar application of either oak extract or oak lactone at approximately 7 days postveraison. Fruits, leaves, and shoots were collected at three different time points, including at maturity. The oak lactone content of fruit was determined by gas chromatography-mass spectrometry, with declining concentrations observed in fruit from grapevines treated with oak lactone with ripening. The concentrations of a β-d-glucopyranoside of 3-methyl-4-hydroxyoctanoic acid in fruits, leaves, and shoots was determined by liquid chromatography-tandem mass spectrometry, with the highest oak lactone glucoside levels observed in leaves of grapevines treated with oak lactone. A glucose-glucose disaccharide was also tentatively identified. These results demonstrate both ring-opening and glycosylation of oak lactone occurred after experimental treatments were imposed. PMID:25912091

  12. Formation, characterization and properties of hydroxyapatite-calcium polycarboxylate and calcium polyvinylphosphonate composites for biomedical applications

    NASA Astrophysics Data System (ADS)

    Greish, Yaser Elhanafy

    A hot pressing technique was used to prepare composites anticipated to be biocompatible. Composites were formed by reactions between tetracalcium phosphate (Ca4(PO4)2O, TetCP) and a biomedical polymer. Polymers used in this study were poly(acrylic-co-itaconic), and poly(vinyl phosphonic acid) (PVPA). The processing technique is commonly used in metallurgy where powder mixtures are hot pressed at elevated pressures, and temperatures. Powder mixtures of TetCP with both polymers were compacted at temperatures up to 300°C, pressures up to 690 MPa for up to 60 minutes. The effects of varying these conditions as well as the TetCP:polymer weight ratios on the reaction kinetics were studied using X-ray diffraction (XRD), Fourier-transform-infrared (FT-IR), 13C, and 31P nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), scanning electron microscope (SEM) and transmission electron microscope (TEM). Results showed that TetCP was converted to hydroxyapatite (Ca10 (PO4)6(OH)2, HAp) with the formation of a Ca salt of the polymer. The reaction kinetics were found to increase with increasing compaction time, temperature and pressure. Formation of anhydrous calcium phosphate (CaHPO4, DCPA) was also observed when PVPA was used. The reaction appears to start with the softening of the polymer when it was heated at temperatures equal to or greater than its glass transition temperature (Tg). The molten polymer flows and surrounds the TetCP grains, permitting a direct reaction to take place on the interface between them. The Ca polysalt appear to form first followed by formation of HAp in case of the copolymer and DCPA then HAp in case of PVPA. Tensile strengths and elastic moduli of the composites increased when the compaction time and temperature were increased. However, when the applied pressure was increased, these properties increased then reduced at higher pressures. The improvement in mechanical properties was related to the increase in densification of the composites with these conditions. These results were correlated to the microstructure of the composites, where HAp crystals are embedded in a network of the calcium salt of the polymer. The reinforcing of the salt by these HAp crystals is considered the main reason of the improvement in mechanical properties. The effects of bioactive glass (bioglassRTM) and wollastonite fibers additions on the mechanical properties and in vitro behavior of these composites were also studied. Results showed that the mechanical properties were improved by ˜50% in case of bioglassRTM and by ˜100% when wollastonite was used. In vitro studies were conducted by immersing these composites in a simulated body fluid (SBF) for up to 14 days, and measuring the changes in the concentrations of Ca, PO4, and SiO4 ions in these solutions. Concentrations of these ions increased with the time of immersion in SBF due to the formation of apatite nuclei on the surface of the composites, suggesting increased bioactivity of the reinforced composites.

  13. From plant surface to plant metabolism: the uncertain fate of foliar-applied nutrients

    PubMed Central

    Fernndez, Victoria; Brown, Patrick H.

    2013-01-01

    The application of agrochemical sprays to the aerial parts of crop plants is an important agricultural practice world-wide. While variable effectiveness is often seen in response to foliar treatments, there is abundant evidence showing the beneficial effect of foliar fertilizers in terms of improving the metabolism, quality, and yields of crops. This mini-review is focused on the major bottlenecks associated with the uptake and translocation of foliar-applied nutrient solutions. A better understanding of the complex scenario surrounding the ultimate delivery of foliar-applied nutrients to sink cells and organs is essential for improving the effectiveness and performance of foliar fertilizers. PMID:23914198

  14. Yolk-Shell Porous Microspheres of Calcium Phosphate Prepared by Using Calcium L-Lactate and Adenosine 5'-Triphosphate Disodium Salt: Application in Protein/Drug Delivery.

    PubMed

    Ding, Guan-Jun; Zhu, Ying-Jie; Qi, Chao; Sun, Tuan-Wei; Wu, Jin; Chen, Feng

    2015-06-26

    A facile and environmentally friendly approach has been developed to prepare yolk-shell porous microspheres of calcium phosphate by using calcium L-lactate pentahydrate (CL) as the calcium source and adenosine 5'-triphosphate disodium salt (ATP) as the phosphate source through the microwave-assisted hydrothermal method. The effects of the concentration of CL, the microwave hydrothermal temperature, and the time on the morphology and crystal phase of the product are investigated. The possible formation mechanism of yolk-shell porous microspheres of calcium phosphate is proposed. Hemoglobin from bovine red cells (Hb) and ibuprofen (IBU) are used to explore the application potential of yolk-shell porous microspheres of calcium phosphate in protein/drug loading and delivery. The experimental results indicate that the as-prepared yolk-shell porous microspheres of calcium phosphate have relatively high protein/drug loading capacity, sustained protein/drug release, favorable pH-responsive release behavior, and a high biocompatibility in the cytotoxicity test. Therefore, the yolk-shell porous microspheres of calcium phosphate have promising applications in various biomedical fields such as protein/drug delivery. PMID:25982303

  15. RBS and XPS analyses of the composite calcium phosphate coatings for biomedical applications

    NASA Astrophysics Data System (ADS)

    Ide-Ektessabi, Ari; Yamaguchi, Tetsuro; Tanaka, Yoshikazu

    2005-12-01

    The calcium phosphate coatings on metallic implants are widely used for biomedical applications. The calcium phosphate coatings require mechanical strength, strong adhesion to the metallic implants, chemical stability and low dissolution into the human body fluid for stable functioning in the corrosive environment of the human body. In this study, a novel approach for improving the calcium phosphate coatings is utilized by adding trace metallic element into the coatings. We focused on teeth enamel, which is the hardest calcium phosphate tissue in the human body. Zn concentration increases exponentially from the interior to the surface of the enamel. As the Zn concentration increases, so the local hardness increases. Our previous studies suggest that Zn has influence on the hardness and other properties of enamel, calcium phosphate tissue. Calcium phosphate coatings doped with Zn was fabricated and characterized. The atomic composition and chemical state were investigated by using Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectrometer (XPS), respectively. Scratch test was also carried out for measuring the adhesion of the coatings.

  16. Influence of foliar copper and nickel applications on sugarcane yields in brown rust infested fields in Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarcane fields with severe brown rust infections have been documented to show a decrease in sugar per hectare yields of up to 1680 kg/ha ($170/ha). Currently, control of this disease is accomplished with multiple fungicide applications. This is a costly practice for sugarcane producers who are alr...

  17. Limited fungicide applications affect foliar and fruit disease severity and phytochemical content of muscadine grape (Vitis rotundifolia Michx.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Berry rot diseases cause significant reductions in yield and quality of muscadine grapes, but these losses may be reduced significantly by fungicide applications. Four studies were conducted to explore the relationship between yield, disease control, berry quality, and phytochemical content followin...

  18. Proteins associated with heat-induced leaf senescence in creeping bentgrass as affected by foliar application of nitrogen, cytokinins, and an ethylene inhibitor.

    PubMed

    Jespersen, David; Huang, Bingru

    2015-02-01

    Heat stress causes premature leaf senescence in cool-season grass species. The objective of this study was to identify proteins regulated by nitrogen, cytokinins, and ethylene inhibitor in relation to heat-induced leaf senescence in creeping bentgrass (Agrostis stolonifera). Plants (cv. Penncross) were foliar sprayed with 18 mM carbonyldiamide (N source), 25 μM aminoethoxyvinylglycine (AVG, ethylene inhibitor), 25 μM zeatin riboside (ZR, cytokinin), or a water control, and then exposed to 20/15°C (day/night) or 35/30°C (heat stress) in growth chambers. All treatments suppressed heat-induced leaf senescence, as shown by higher turf quality and chlorophyll content, and lower electrolyte leakage in treated plants compared to the untreated control. A total of 49 proteins were responsive to N, AVG, or ZR under heat stress. The abundance of proteins in photosynthesis increased, with ribulose-1,5-bisphosphate carboxylase/oxygenase affected by all three treatments, chlorophyll a/b-binding protein by AVG and N or Rubisco activase by AVG. Proteins for amino acid metabolism were upregulated, including alanine aminotransferase by three treatments and ferredoxin-dependent glutamate synthase by AVG and N. Upregulated proteins also included catalase by AVG and N and heat shock protein by ZR. Exogenous applications of AVG, ZR, or N downregulated proteins in respiration (enolase, glyceraldehyde 3-phosphate dehydrogenase, and succinate dehygrogenase) under heat stress. Alleviation of heat-induced senescence by N, AVG, or ZR was associated with enhanced protein abundance in photosynthesis and amino acid metabolism and stress defense systems (heat shock protection and antioxidants), as well as suppression of those imparting respiration metabolism. PMID:25407697

  19. Biofilm-induced calcium carbonate precipitation: application in the subsurface

    NASA Astrophysics Data System (ADS)

    Phillips, A. J.; Eldring, J.; Lauchnor, E.; Hiebert, R.; Gerlach, R.; Mitchell, A. C.; Esposito, R.; Cunningham, A. B.; Spangler, L.

    2012-12-01

    We have investigated mitigation strategies for sealing high permeability regions, like fractures, in the subsurface. This technology has the potential to, for example, improve the long-term security of geologically-stored carbon dioxide (CO2) by sealing fractures in cap rocks or to mitigate leakage pathways to prevent contamination of overlying aquifers from hydraulic fracturing fluids. Sealing technologies using low-viscosity fluids are advantageous since they potentially reduce the necessary injection pressures and increase the radius of influence around injection wells. In this technology, aqueous solutions and suspensions are used to promote microbially-induced mineral precipitation which can be applied in subsurface environments. To this end, a strategy was developed to twice seal a hydraulically fractured, 74 cm (2.4') diameter Boyles Sandstone core, collected in North-Central Alabama, with biofilm-induced calcium carbonate (CaCO3) precipitates under ambient pressures. Sporosarcina pasteurii biofilms were established and calcium and urea containing reagents were injected to promote saturation conditions favorable for CaCO3 precipitation followed by growth reagents to resuscitate the biofilm's ureolytic activity. Then, in order to evaluate this process at relevant deep subsurface pressures, a novel high pressure test vessel was developed to house the 74 cm diameter core under pressures as high as 96 bar (1,400 psi). After determining that no impact to the fracture permeability occurred due to increasing overburden pressure, the fractured core was sealed under subsurface relevant pressures relating to 457 meters (1,500 feet) below ground surface (44 bar (650 psi) overburden pressure). After fracture sealing under both ambient and subsurface relevant pressure conditions, the sandstone core withstood three times higher well bore pressure than during the initial fracturing event, which occurred prior to biofilm-induced CaCO3 mineralization. These studies suggest biofilm-induced CaCO3 precipitation technologies may potentially seal and strengthen high permeability regions or fractures (either natural or induced) in the subsurface. Novel high pressure test vessel to investigate biogeochemical processes under relevant subsurface scales and pressures.

  20. Alleviating aluminum toxicity in an acid sulfate soil from Peninsular Malaysia by calcium silicate application

    NASA Astrophysics Data System (ADS)

    Elisa, A. A.; Ninomiya, S.; Shamshuddin, J.; Roslan, I.

    2016-03-01

    In response to human population increase, the utilization of acid sulfate soils for rice cultivation is one option for increasing production. The main problems associated with such soils are their low pH values and their associated high content of exchangeable Al, which could be detrimental to crop growth. The application of soil amendments is one approach for mitigating this problem, and calcium silicate is an alternative soil amendment that could be used. Therefore, the main objective of this study was to ameliorate soil acidity in rice-cropped soil. The secondary objective was to study the effects of calcium silicate amendment on soil acidity, exchangeable Al, exchangeable Ca, and Si content. The soil was treated with 0, 1, 2, and 3 Mg ha-1 of calcium silicate under submerged conditions and the soil treatments were sampled every 30 days throughout an incubation period of 120 days. Application of calcium silicate induced a positive effect on soil pH and exchangeable Al; soil pH increased from 2.9 (initial) to 3.5, while exchangeable Al was reduced from 4.26 (initial) to 0.82 cmolc kg-1. Furthermore, the exchangeable Ca and Si contents increased from 1.68 (initial) to 4.94 cmolc kg-1 and from 21.21 (initial) to 81.71 mg kg-1, respectively. Therefore, it was noted that calcium silicate was effective at alleviating Al toxicity in acid sulfate, rice-cropped soil, yielding values below the critical level of 2 cmolc kg-1. In addition, application of calcium silicate showed an ameliorative effect as it increased soil pH and supplied substantial amounts of Ca and Si.

  1. Soil acidification and foliar nutrient status of Ontario's deciduous forest in 1986 and 2005.

    PubMed

    Miller, Diane E; Watmough, Shaun A

    2009-02-01

    To assess the impacts of the decline in sulphur (S) deposition over the past 20 years in Ontario, soil chemistry and sugar maple (Acer saccharum Marsh) foliar chemistry were measured at 17 sites in south and central Ontario in 2005 and compared with archived samples collected in 1986. Foliar S concentrations were lower in 2005, reflecting the decline in S deposition whereas foliar N remained unchanged, reflecting the lack of change in N deposition in Ontario. Mineral soil pH, exchangeable base cations were lower in 2005 whereas total S, N and cation exchange capacity (CEC) were unchanged. Foliar concentrations of Ca were positively related to soil Ca levels in the A-horizon and were lower in 2005. Despite evidence of increasing soil acidity and losses of calcium, foliar base cation concentrations at most sites were adequate for sugar maple and forest health in terms of canopy appearance (Decline Index) improved. PMID:18824282

  2. Natural rubber latex coated with calcium phosphate for biomedical application.

    PubMed

    Borges, Felipe Azevedo; Filho, Edson de Almeida; Miranda, Matheus Carlos Romeiro; Dos Santos, Mrcio Luiz; Herculano, Rondinelli Donizetti; Guastaldi, Antnio Carlos

    2015-12-01

    Natural rubber latex (NRL) is a flexible biomembrane that possesses angiogenic properties and has recently been used for guided bone regeneration, enhancing healing without fibrous tissue, allergies or rejection. Calcium phosphate (Ca/P) ceramics have chemical, biological, and mechanical properties similar to mineral phase of bone, and ability to bond to the host tissue, although it can disperse from where it is applied. Therefore, to create a composite that could enhance the properties of both materials, NRL biomembranes were coated with Ca/P. NRL biomembranes were soaked in 1.5 times concentrated SBF solution for sevendays, avoiding the use of high temperatures. SEM showed that Ca/P has been coated in NRL biomembrane, XRD showed low crystallinity and FTIR showed that is the carbonated type B. Furthermore, hemolysis of erythrocytes, quantified spectrophotometrically using materials (Ca/P, NRL, and NRL+Ca/P) showed no hemolytic effects up to 0.125mg/mL (compounds and mixtures), indicating no detectable disturbance of the red blood cell membranes. The results show that the biomimetic is an appropriate method to coat NRL with Ca/P without using high temperatures, aiming a new biomembrane to improve guided bone regeneration. PMID:26307406

  3. Oxidative and Molecular Responses in Capsicum annuum L. after Hydrogen Peroxide, Salicylic Acid and Chitosan Foliar Applications

    PubMed Central

    Mejía-Teniente, Laura; de Dalia Durán-Flores, Flor; Chapa-Oliver, Angela María; Torres-Pacheco, Irineo; Cruz-Hernández, Andrés; González-Chavira, Mario M.; Ocampo-Velázquez, Rosalía V.; Guevara-González, Ramón G.

    2013-01-01

    Hydrogen peroxide (H2O2) is an important ROS molecule (Reactive oxygen species) that serves as a signal of oxidative stress and activation of signaling cascades as a result of the early response of the plant to biotic stress. This response can also be generated with the application of elicitors, stable molecules that induce the activation of transduction cascades and hormonal pathways, which trigger induced resistance to environmental stress. In this work, we evaluated the endogenous H2O2 production caused by salicylic acid (SA), chitosan (QN), and H2O2 elicitors in Capsicum annuum L. Hydrogen peroxide production after elicitation, catalase (CAT) and phenylalanine ammonia lyase (PAL) activities, as well as gene expression analysis of cat1, pal, and pathogenesis-related protein 1 (pr1) were determined. Our results displayed that 6.7 and 10 mM SA concentrations, and, 14 and 18 mM H2O2 concentrations, induced an endogenous H2O2 and gene expression. QN treatments induced the same responses in lesser proportion than the other two elicitors. Endogenous H2O2 production monitored during several days, showed results that could be an indicator for determining application opportunity uses in agriculture for maintaining plant alert systems against a stress. PMID:23676352

  4. Synthesis of spherical calcium phosphate particles for dental and orthopedic applications

    PubMed Central

    Bohner, Marc; Tadier, Solène; van Garderen, Noémie; de Gasparo, Alex; Döbelin, Nicola; Baroud, Gamal

    2013-01-01

    Calcium phosphate materials have been used increasingly in the past 40 years as bone graft substitutes in the dental and orthopedic fields. Accordingly, numerous fabrication methods have been proposed and used. However, the controlled production of spherical calcium phosphate particles remains a challenge. Since such particles are essential for the synthesis of pastes and cements delivered into the host bone by minimally-invasive approaches, the aim of the present document is to review their synthesis and applications. For that purpose, production methods were classified according to the used reagents (solutions, slurries, pastes, powders), dispersion media (gas, liquid, solid), dispersion tools (nozzle, propeller, sieve, mold), particle diameters of the end product (from 10 nm to 10 mm), and calcium phosphate phases. Low-temperature calcium phosphates such as monetite, brushite or octacalcium phosphate, as well as high-temperature calcium phosphates, such as hydroxyapatite, β-tricalcium phosphate or tetracalcium phosphate, were considered. More than a dozen production methods and over hundred scientific publications were discussed. PMID:23719177

  5. Foliar application of methyl jasmonate induced physio-hormonal changes in Pisum sativum under diverse temperature regimes.

    PubMed

    Shahzad, Raheem; Waqas, Muhammad; Khan, Abdul Latif; Hamayun, Muhammad; Kang, Sang-Mo; Lee, In-Jung

    2015-11-01

    Global climate change brings with it unwarranted shifts in both abiotic (heat stress, cold stress, wind, precipitation) and biotic (pathogens, pests) environmental factors, thus posing a threat to agricultural productivity across the world. In plants, lodging due to storms or herbivory causes wounding stress and consequently enhances endogenous jasmonates. In response, the plant growth is arrested as plant defense is prioritized. We pre-treated pea plants with elevated methyl jasmonate (MeJA) levels i.e. 50 ?M, 100 ?M and 200 ?M under controlled growth chamber conditions. The pre-treated plants were then kept at 40 C (heat stress--HS), 4 C (cold stress--CS) and 20 C (optimum/control temperature--OT) for 72 h. The effect of such treatments on plant growth attributes, photosynthesis, stomatal conductance, cell death rate, and regulation of endogenous hormones were observed. Elevated MeJA application hindered plant growth attributes under HS, CS and OT conditions. Moreover, elevated MeJA levels lowered the rate of photosynthesis and stomatal conductance, induced stomatal closure, caused higher cells mortality in leaves under HS, CS, and OT conditions. Endogenous ABA contents significantly declined in all MeJA treatments under HS and OT, but increased under CS conditions. Exogenous MeJA enhanced endogenous jasmonic acid contents of pea plants, but altered endogenous salicylic acid contents under varying temperatures. Current study shows that higher concentrations of exogenous MeJA strengthen plant defense mechanism by hindering plant growth under stress conditions. PMID:26379199

  6. 40 CFR 424.40 - Applicability; description of the covered calcium carbide furnaces with wet air pollution control...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable...

  7. 40 CFR 424.40 - Applicability; description of the covered calcium carbide furnaces with wet air pollution control...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable...

  8. 40 CFR 424.40 - Applicability; description of the covered calcium carbide furnaces with wet air pollution control...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable...

  9. 40 CFR 424.40 - Applicability; description of the covered calcium carbide furnaces with wet air pollution control...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable...

  10. 40 CFR 424.40 - Applicability; description of the covered calcium carbide furnaces with wet air pollution control...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable...

  11. [The application of 4-aminopyridine in calcium channel inhibitors acute poisoning].

    PubMed

    Fiszer, Marta; Ko?aci?ski, Zbigniew; Rechci?ski, Tomasz

    2007-01-01

    Calcium channel inhibitors have been extensively used to treat arterial hypertension, ischaemic heart disease and supraventricular rhythm irregularities. The poisonings by that category of drugs are extremely dangerous, particularly when accompanied by intoxication with other drugs affecting the circulatory function. This paper reports 3 cases of poisonings with calcium channel inhibitors (verapamil and diltiazem) in combination with angiotensin convertase inhibitors and nonselective beta-adrenolytics. Circulatory insufficiency and cardiac rhythm abnormalities were noted in all reported cases, in one in the form of ventricular bigeminy and two episodes of ventricular fibrillation, while in the two other cases in the form of 1 degree atrioventricular block. The persisting hypotonia combined with heart rhythm disturbances could not be prevented by the typical conservative treatment involving intravenous administration of infusion fluids, calcium formulations, catecholamines and atropin. The application of 4-amino-pyridine (Pymadin) caused that arterial tension and heart rate were higher, and the heart rhythm disturbances disappeared. The reported cases suggest a beneficial effect of 4-aminopyridine used to treat cases of poisonings by calcium channel inhibitors; however, up to the present time, no detailed procedures have been determined for 4-aminopyridine administration in cases like those reported above. 4-aminopyridine has not been included in the list of the antidotes approved by the WHO and, therefore, broader tests and more clinical observations are required to confirm its therapeutic value. PMID:17724889

  12. ATP-stabilized amorphous calcium carbonate nanospheres and their application in protein adsorption.

    PubMed

    Qi, Chao; Zhu, Ying-Jie; Lu, Bing-Qiang; Zhao, Xin-Yu; Zhao, Jing; Chen, Feng; Wu, Jin

    2014-05-28

    Calcium carbonate is a common substance found in rocks worldwide, and is the main biomineral formed in shells of marine organisms and snails, pearls and eggshells. Amorphous calcium carbonate (ACC) is the least stable polymorph of calcium carbonate, which is so unstable under normal conditions that it is difficult to be prepared in vitro because it rapidly crystallizes to form one of the more stable polymorphs in aqueous solution. Herein, we report the successful synthesis of highly stable ACC nanospheres in vitro using adenosine 5'-triphosphate disodium salt (ATP) as a stabilizer. The effect of ATP on the stability of ACC nanospheres is investigated. Our experiments show that ATP plays an unique role in the stabilization of ACC nanospheres in aqueous solution. Moreover, the as-prepared ACC nanospheres are highly stable in phosphate buffered saline for a relatively long period of time (12 days) even under relatively high concentrations of calcium and phosphate ions. The cytotoxicity tests show that the as-prepared highly stable ACC nanospheres have excellent biocompatibility. The highly stable ACC nanospheres have high protein adsorption capacity, implying that they are promising for applications in biomedical fields such as drug delivery and protein adsorption. PMID:24578276

  13. 75 FR 28608 - Calcium Hydroxide; Receipt of Application for Emergency Exemption, Solicitation of Public Comment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ...EPA has received a quarantine exemption request from the Hawaii Department of Agriculture to use the pesticide calcium hydroxide (CAS No. 1305-62-0) to treat up to 1,000 acres of outdoor potted and field-grown ornamental plants, groundcover/floors, and perimeters of commercial nurseries to control Eleutherodactylus frogs. The applicant proposes the use of a new chemical which has not been......

  14. Alleviating aluminium toxicity on an acid sulphate soils in Peninsular Malaysia with application of calcium silicate

    NASA Astrophysics Data System (ADS)

    Elisa, A. A.; Ninomiya, S.; Shamshuddin, J.; Roslan, I.

    2015-10-01

    A study was conducted to alleviate Al toxicity of an acid sulphate soils collected from paddy cultivation area in Kedah, Peninsular Malaysia. For this purpose, the collected acid sulphate soils were treated with calcium silicate. The treated soils were incubated for 120 days in submerged condition in a glasshouse. Subsamples were collected every 30 days throughout the incubation period. Soil pH and exchangeable Al showed positive effect; soil pH increased from 2.9 to 3.5, meanwhile exchangeable Al was reduced from 4.26 to 0.82 cmolc kg-1, which was well below the critical Al toxicity level for rice growth of 2 cmolc kg-1. It was noted that the dissolution of calcium silicate (CaSiO3) supplied substantial amount of Ca2+ and H4SiO42- ions into the soil, noted with increment in Si (silicate) content from 21.21 to 40 mg kg-1 at day 30 and reduction of exchangeable Al at day 90 from 4.26 to below 2 cmolc kg-1. During the first 60 days of incubation, Si content was positively correlated with soil pH, while the exchangeable Al was negatively correlated with Si content. It is believed that the silicate anions released by calcium silicate were active in neutralizing H+ ions that governs the high acidity (pH 2.90) of the acid sulphate soils. This scenario shows positive effect of calcium silicate to reduce soil acidity, therefore creates a favourable soil condition for good rice growth during its vegetative phase (30 days). Thus, application of calcium silicate to alleviate Al toxicity of acid sulphate soils for rice cultivation is a good soil amendment.

  15. Gas phase laser synthesis and processing of calcium phosphate nanoparticles for biomedical applications

    NASA Astrophysics Data System (ADS)

    Bapat, Parimal V.

    Biochemical processes make pervasive use of calcium and phosphate ions. Calcium phosphate salts that are naturally nontoxic and bioactive have been used for several medical applications in form of coatings and micropowders. Nanoparticle-based calcium phosphates have been shown to be internalized by living cells and be effective in DNA transfection, drug delivery, and transport of fluorophores for imaging of intracellular processes. They are also expected to interact strongly with cell adhesive proteins and are therefore promising elements in approaches to mimic the complex environment of the extra cellular matrix of bone. Harnessing this biomedical potential requires the ability to control the numerous characteristics of nanophase calcium phosphates that affect biological response, including nanoparticle chemical composition, crystal phase, crystallinity, crystallographic orientation of exposed faces, size, shape, surface area, number concentration, and degree of aggregation. This dissertation focuses on the use of laser-induced gas-phase synthesis for creation of calcium phosphate nanoparticles, and corresponding nanoparticle-based substrates that could offer new opportunities for guiding biological responses through well-controlled biochemical and topological cues. Gas-phase synthesis of nanoparticles has several characteristics that could enhance control over particle morphology, crystallinity, and surface area, compared to liquid-phase techniques. Synthesis from gas-phase precursors can be carried out at high temperatures and in high-purity inert or reactive gas backgrounds, enabling good control of chemistry, crystal structure, and purity. Moreover, the particle mean free path and number concentration can be controlled independently. This allows regulation of interparticle collision rates, which can be adjusted to limit aggregation. High-temperature synthesis of well-separated particles is therefore possible. In this work high power lasers are employed to vaporize microcrystalline calcium phosphate materials to generate an aerosol of nanoparticles which is further processed and deposited using principles of aerosol mechanics. Particles and resulting particle-based systems are analyzed by transmission electron microscopy, atomic force microscopy, X-ray diffraction, and optical absorption. Obtained substrates are functionalized with cell adhesive peptides. Findings show that laser-induced gas-phase synthesis provides attractive new dimensions in the controlled fabrication of calcium phosphate nanoparticles, including manipulation not only of size and chemical composition, but also crystal phase make-up, fractal structure, and nanotopography of derived substrates.

  16. Three-year growth response of young Douglas-fir to nitrogen, calcium, phosphorus, and blended fertilizers in Oregon and Washington

    USGS Publications Warehouse

    Mainwaring, Douglas B.; Maguire, Douglas A.; Perakis, Steven S.

    2014-01-01

    Studies of nutrient limitation in Douglas-fir forests of the Pacific Northwest focus predominantly on nitrogen, yet many stands demonstrate negligible or even negative growth response to nitrogen fertilization. To understand what nutrients other than nitrogen may limit forest productivity in this region, we tested six fertilizer treatments for their ability to increase stem volume growth response of dominant and co-dominant trees in young Douglas-fir plantations across a range of foliar and soil chemistry in western Oregon and Washington. We evaluated responses to single applications of urea, lime, calcium chloride, or monosodium phosphate at 16 sites, and to two site-specific nutrients blends at 12 of these sites. Across sites, the average stem volume growth increased marginally with urea, lime, and phosphorus fertilization. Fertilization responses generally aligned with plant and soil indicators of nutrient limitation. Response to nitrogen addition was greatest on soils with low total nitrogen and high exchangeable calcium concentrations. Responses to lime and calcium chloride additions were greatest at sites with low foliar calcium and low soil pH. Response to phosphorus addition was greatest on sites with low foliar phosphorus and high soil pH. Blended fertilizers yielded only marginal growth increases at one site, with no consistent effect across sites. Overall, our results highlight that calcium and phosphorus can be important growth limiting nutrients on specific sites in nitrogen-rich Douglas-fir forests of the Pacific Northwest.

  17. Chemolysis of calcium oxalate stones: study in vitro and possible clinical application.

    PubMed

    Kustov, Andrey V; Shevyrin, Alexey A; Strel'nikov, Alexander I; Smirnov, Pavel R; Trostin, Vyacheslav N

    2012-06-01

    The flow cell modeling clinical conditions have been used to study the interaction between dilute chemolytic solutions and large calcium oxalate renal stones. The stone treatment with 5% disodium ethylenediaminetetraacetate aqueous solutions or citrate buffer are found not to provide notable disruption of the samples studied. The significant improvement is reached with the mixed compositions containing both natural and synthetic chelating reagents:citrate and ethylenediaminetetraacetate ions as well as an antibiotic. Description of the chemolytic irrigation, numerical results and their possible clinical application are the main topic of the present research. PMID:22089056

  18. Watermelon foliar fungicide timing trial

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar diseases are a persistent threat to watermelon production in Oklahoma. Several diseases that include anthracnose, downy mildew, and powdery mildew can result in yield and fruit quality losses when foliage is damaged. Effective fungicides are available for the control of these diseases. How...

  19. FOLIAR POTASSIUM IMPROVES CANTALOUPE MARKETABLE AND NUTRITIONAL QUALITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potassium (K) is needed to optimize both crop yield and quality. Roots, the sole source of K uptake, are poor suppliers of K during fruit crop production. This study has shown that supplementing optimal soil K with additional foliar K applications, superficially during cantaloupe fruit growth, can...

  20. [Effects of calcium fertilizer application on peanut growth, physiological characteristics, yield and quality under drought stress].

    PubMed

    Gu, Xue-hua; Sun, Lian-qiang; Gao, Bo; Sun, Qi-ze; Liu, Chen; Zhang, Jia-lei; Li, Xiang-dong

    2015-05-01

    An experiment was carried out to study the effects of different rates of calcium application on peanut growth, physiological characteristics, yield and quality under drought stress at pegging stage and pod setting stage in pool cultivation with rainproof, using variety 606 as experimental material. The results showed that applying Ca fertilizer under drought stress could promote peanut growth, increase the chlorophyll content, leaf photosynthetic rate and the root vitality, increase the recovery ability of peanut during rewatering after drought stress, alleviate the impact of drought stress on peanut. Applying Ca fertilizer under drought stress increased pod and kernel yields because of the increase of kernel rate and pod number per plant. It also increased the fat and protein contents of peanut kernel, and improved peanut kernel quality under drought stress. It was suggested that 300 kg hm(-2) Ca application is the best choice to alleviate the impact of drought stress on peanut. PMID:26571662

  1. Biomineralization and Size Control of Stable Calcium Phosphate Core Protein Shell Nanoparticles: Potential for Vaccine Applications

    PubMed Central

    Chiu, David; Zhou, Weibin; Kitayaporn, Sathana; Schwartz, Daniel T.; Murali-Krishna, Kaja; Kavanagh, Terrance J.; Baneyx, Franois

    2012-01-01

    Calcium phosphate (CaP) polymorphs are nontoxic, biocompatible and hold promise in applications ranging from hard tissue regeneration to drug delivery and vaccine design. Yet, simple and robust routes for the synthesis of protein-coated CaP nanoparticles in the sub-100 nm size range remain elusive. Here, we used cell surface display to identify disulfide-constrained CaP binding peptides that, when inserted within the active site loop of E. coli Thioredoxin 1 (TrxA), readily and reproducibly drive the production of nanoparticles that are 5070 nm in hydrodynamic diameter and consist of an approximately 25 nm amorphous calcium phosphate (ACP) core stabilized by the protein shell. Like bone and enamel proteins implicated in biological apatite formation, peptides supporting nanoparticle production were acidic. They also required presentation in a loop for high affinity ACP binding since elimination of the disulfide bridge caused a nearly 3-fold increase in hydrodynamic diameters. When compared to a commercial aluminum phosphate adjuvant, the small core-shell assemblies led to a 3-fold increase in mice anti-TrxA titers three weeks post-injection, suggesting that they might be useful vehicles for adjuvanted antigen delivery to dendritic cells. PMID:22263898

  2. Ion microprobe measurement of strontium isotopes in calcium carbonate with application to salmon otoliths

    USGS Publications Warehouse

    Weber, P.K.; Bacon, C.R.; Hutcheon, I.D.; Ingram, B.L.; Wooden, J.L.

    2005-01-01

    The ion microprobe has the capability to generate high resolution, high precision isotopic measurements, but analysis of the isotopic composition of strontium, as measured by the 87Sr/ 86Sr ratio, has been hindered by isobaric interferences. Here we report the first high precision measurements of 87Sr/ 86Sr by ion microprobe in calcium carbonate samples with moderate Sr concentrations. We use the high mass resolving power (7000 to 9000 M.R.P.) of the SHRIMP-RG ion microprobe in combination with its high transmission to reduce the number of interfering species while maintaining sufficiently high count rates for precise isotopic measurements. The isobaric interferences are characterized by peak modeling and repeated analyses of standards. We demonstrate that by sample-standard bracketing, 87Sr/86Sr ratios can be measured in inorganic and biogenic carbonates with Sr concentrations between 400 and 1500 ppm with ???2??? external precision (2??) for a single analysis, and subpermil external precision with repeated analyses. Explicit correction for isobaric interferences (peak-stripping) is found to be less accurate and precise than sample-standard bracketing. Spatial resolution is ???25 ??m laterally and 2 ??m deep for a single analysis, consuming on the order of 2 ng of material. The method is tested on otoliths from salmon to demonstrate its accuracy and utility. In these growth-banded aragonitic structures, one-week temporal resolution can be achieved. The analytical method should be applicable to other calcium carbonate samples with similar Sr concentrations. Copyright ?? 2005 Elsevier Ltd.

  3. Fatigue Behavior of Ti-6-4 Alloy with Application of Calcium Phosphate

    NASA Astrophysics Data System (ADS)

    Kamboj, Jaspal Singh

    It is key to consider a material's mechanical properties when determining its use for any given application, including biomaterial implantations. One such characteristic includes the fatigue life, which is determined by repeatedly cycling specified amounts of load on any given material. The fatigue life is then measured according to how many cycles of load the material can undergo before fracture. When a material is introduced to the human body it is usually expected that the life of the material will not match that of the patient. It is crucial to understand the fatigue life of the material before implantation to pre-diagnose how often and when the implant will need to be replaced. The purpose of this project is to help determine and compare the fatigue behaviors of a commonly used biocompatible coating on Titanium 6-4 metal alloy. The comparison will help identify how the material properties vary with the addition of calcium phosphate when compared to the bare alloy itself. Multiple, small rectangular samples were cut by electrical discharge machining (EDM) of which half were covered with calcium phosphate coating. Fatigue crack initiations and propagation would then be analyzed using scanning electron microscopy (SEM) to help determine the nature of the damage processes. It was found that the fatigue life of the coated samples varied at different stresses but was greater than the bare samples, and particularly high in the 900 MPa - 1000 MPa stress range.

  4. Antibacterial Properties of ZnO/Calcium Alginate Composite and Its Application in Wastewater Treatment.

    PubMed

    Zhang, Fengqin; Li, Xiaolong; He, Nongyue; Lin, Qinlu

    2015-05-01

    In this study, the antibacterial activities of ZnO with various morphologies were evaluated. A possible mechanism of antibacterial activities of dumbbell like ZnO was proposed based on the microscopic studies of the interaction between bacterial and dumbbell like ZnO, and also based on the antibacterial activity of ZnO enveloped with semi permeable membrane. Monosodium glutamate (MSG) wastewater and soy sauce wastewater were treated by M. purpureus using ZnO/calcium alginate carrier. The attached and suspended biomass in MSG wastewater reached to 228 mg/g and 74 mg/g, while, the attached and suspended biomass in soy sauce wastewater was 130 mg/g and 66 mg/g, respectively. The levels of chemical oxide demand (COD), biological oxide demand (BOD5), SO4(2-) and NH3-N in the treated MSG wastewater were distinctive lower than those detected in the raw wastewater. This ZnO/calcium alginate carrier method could be utilized as an alternative to the traditional anaerobic/aerobic methods in the application of food processing wastewater treatment. PMID:26505013

  5. Calcium supplements

    MedlinePLUS

    ... provides 200 to 400 mg of calcium. Calcium citrate: This is a more expensive form of calcium. ... common in people over age 50) absorb calcium citrate better than calcium carbonate. Other forms, such as ...

  6. Calcium Orthophosphate-Containing Biocomposites and Hybrid Biomaterials for Biomedical Applications

    PubMed Central

    Dorozhkin, Sergey V.

    2015-01-01

    The state-of-the-art on calcium orthophosphate (CaPO4)-containing biocomposites and hybrid biomaterials suitable for biomedical applications is presented. Since these types of biomaterials offer many significant and exciting possibilities for hard tissue regeneration, this subject belongs to a rapidly expanding area of biomedical research. Through the successful combinations of the desired properties of matrix materials with those of fillers (in such systems, CaPO4 might play either role), innovative bone graft biomaterials can be designed. Various types of CaPO4-based biocomposites and hybrid biomaterials those are either already in use or being investigated for biomedical applications are extensively discussed. Many different formulations in terms of the material constituents, fabrication technologies, structural and bioactive properties, as well as both in vitro and in vivo characteristics have been already proposed. Among the others, the nano-structurally controlled biocomposites, those containing nanodimensional compounds, biomimetically fabricated formulations with collagen, chitin and/or gelatin, as well as various functionally graded structures seem to be the most promising candidates for clinical applications. The specific advantages of using CaPO4-based biocomposites and hybrid biomaterials in the selected applications are highlighted. As the way from a laboratory to a hospital is a long one and the prospective biomedical candidates have to meet many different necessities, the critical issues and scientific challenges that require further research and development are also examined. PMID:26262645

  7. Secondary Ion Mass Spectrometers (SIMS) for calcium isotope measurements as an application to biological samples

    NASA Astrophysics Data System (ADS)

    Craven, S. M.; Hoenigman, J. R.; Moddeman, W. E.

    1981-11-01

    The potential use of secondary ion mass spectroscopy (SIMS) to analyze biological samples for calcium isotopes is discussed. Comparison of UTI and Extranuclear based quadrupole systems is made on the basis of the analysis of CaO and calcium metal. The Extranuclear quadrupole based system is superior in resolution and sensitivity to the UTI system and is recommended. For determination of calcium isotopes to within an accuracy of a few percent a high resolution quadrupole, such as the Extranuclear, and signal averaging capability are required. Charge neutralization will be mandated for calcium oxide, calcium nitrate, or calcium oxalate. SIMS is not capable of the high precision and high accuracy results possible by thermal ionization methods, but where faster analysis is desirable with an accuracy of a few percent, SIMS is a viable alternative.

  8. Secondary ion mass spectrometers (SIMS) for calcium isotope measurements as an application to biological samples

    SciTech Connect

    Craven, S.M.; Hoenigman, J.R.; Moddeman, W.E.

    1981-11-20

    The potential use of secondary ion mass spectroscopy (SIMS) to analyze biological samples for calcium isotopes is discussed. Comparison of UTI and Extranuclear based quadrupole systems is made on the basis of the analysis of CaO and calcium metal. The Extranuclear quadrupole based system is superior in resolution and sensitivity to the UTI system and is recommended. For determination of calcium isotopes to within an accuracy of a few percent a high resolution quadrupole, such as the Extranuclear, and signal averaging capability are required. Charge neutralization will be mandated for calcium oxide, calcium nitrate, or calcium oxalate. SIMS is not capable of the high precision and high accuracy results possible by thermal ionization methods, but where faster analysis is desirable with an accuracy of a few percent, SIMS is a viable alternative.

  9. Application of reutilization technology to calcium fluoride sludge from semiconductor manufacturers.

    PubMed

    Liu, Wei-Ting; Li, Kung-Cheh

    2011-01-01

    Glass ceramics were prepared from mixtures of wastes generated from refining of waste glass and semiconductor industrial wastewater sludge. The aim is then indeed to study the possible use and effects of integrating calcium fluoride (CaF2) as present in semiconductor wastewater sludge in the silica (glass) melts. CaF2 sludge was blended with a conditioner according to characteristics of the target. Calcium oxide-silicon dioxide-aluminum oxide system glass ceramics have relatively high melting points. Addition of CaF2 sludge to fluxes can significantly reduce the melting point and hence improve the kinetics of the reactions. CaF2 sludge and waste glass were co-melted in various ratios to elucidate their interactions at various heating temperatures. The results indicate that the lowest melting temperature was 1163 degrees C, obtained for the CaF2 sludge-waste glass mixture at a ratio 6:4 (wt:wt), which is significantly lower than that of CaF2 sludge (1378 degrees C). The benefits of using melting to dispose of sludge are the reduction of waste and the fixation of heavy metals. Heat treatment was used to convert the obtained glass into glass ceramics. Heavy metal leaching tests revealed that melting conditions lowered the heavy metal concentrations in the leachate to an order of magnitude lower than that in the sludge. Consequently, industrial sludge can be safely used as a fine aggregate material for a potentially wide range of construction applications. PMID:21305892

  10. Application of BY-2 cell model in evaluating an effect of newly prepared potential calcium channel blockers.

    PubMed

    Bobal, Pavel; Otevrel, Jan; Poborilova, Zuzana; Vaverkova, Veronika; Csollei, Jozef; Babula, Petr

    2015-07-01

    Calcium channel blockers represent a group of therapeutically important compounds that have found an application in treatment of systemic vascular resistance and arterial pressure, eventually angina pectoris. We studied possibility of application of a BY-2 cell model to evaluate the potential of newly prepared potential calcium channel blockers. In the preliminary experiment, toxicity of studied compounds was determined. In the next experiment, we evaluated possible protective effect of studied compounds on programmed cell death induced by hydrogen peroxide on the BY-2 cells. Calcium channel blocker lanthanum ions and imidazole, inhibitor of NAD(P)H oxidase (EC 1.6.3.1) that prevents reactive oxygen species formation and programmed cell death, were used as reference compounds to compare the effect of studied compounds. We studied changes in the cell viability and growth as well as markers of cell proliferation, levels of intracellular free calcium ions, reactive oxygen species, lipid peroxidation, and markers of programmed cell death, mitochondrial membrane potential and caspase-like activity. Late signs of programmed cell death (changes in nuclear architecture) were also evaluated. Our experiments revealed protective potential of studied compounds against programmed cell death induced by hydrogen peroxide and possibility of application of the BY-2 cell culture to evaluate pharmacological effects of studied compounds in preliminary tests. PMID:26142519

  11. In situ forming IPN hydrogels of calcium alginate and dextran-HEMA for biomedical applications.

    PubMed

    Pescosolido, Laura; Vermonden, Tina; Malda, Jos; Censi, Roberta; Dhert, Wouter J A; Alhaique, Franco; Hennink, Wim E; Matricardi, Pietro

    2011-04-01

    In situ forming hydrogels, which allow for the modulation of physico-chemical properties, and in which cell response can be tailored, are providing new opportunities for biomedical applications. Here, we describe interpenetrating polymer networks (IPNs) based on a physical network of calcium alginate (Alg-Ca), interpenetrated with a chemical one based on hydroxyethyl-methacrylate-derivatized dextran (dex-HEMA). IPNs with different concentration and degree of substitution of dex-HEMA were characterized and evaluated for protein release as well as for the behavior of embedded cells. The results demonstrated that the properties of the semi-IPNs, which are obtained by dissolution of dex-HEMA chains into the Alg-Ca hydrogels, would allow for injection of these hydrogels. Degradation times of the IPNs after photocross-linking could be tailored from 15 to 180 days by the concentration and the degree of substitution of dex-HEMA. Further, after an initial burst release, bovine serum albumin was gradually released from the IPNs over approximately 15 days. Encapsulation of expanded chondrocytes in the IPNs revealed that cells remained viable and, depending on the composition, were able to redifferentiate, as was demonstrated by the deposition of collagen type II. These results demonstrate that these IPNs are attractive materials for pharmaceutical and biomedical applications due to their tailorable mechanical and degradation characteristics, their release kinetics and biocompatibility. PMID:21130186

  12. Ion Association versus Ion Interaction Models in Examining Electrolyte Solutions: Application to Calcium Hydroxide Solubility Equilibrium

    ERIC Educational Resources Information Center

    Menndez, M. Isabel; Borge, Javier

    2014-01-01

    The heterogeneous equilibrium of the solubility of calcium hydroxide in water is used to predict both its solubility product from solubility and solubility values from solubility product when inert salts, in any concentration, are present. Accepting the necessity of including activity coefficients to treat the saturated solution of calcium

  13. Influence of soil pH and application rate on the oxidation of calcium sulfite derived from flue gas desulfurization.

    PubMed

    Lee, Y B; Bigham, J M; Dick, W A; Jones, F S; Ramsier, C

    2007-01-01

    Calcium sulfite hemihydrate (CaSO(3).0.5H2O), a common byproduct of coal-fired utilities, is fairly insoluble and can decompose to release toxic SO2 under highly acidic soil conditions; however, it can also oxidize to form gypsum. The objective of this study was to examine the effects of application rate and soil pH on the oxidation of calcium sulfite under laboratory conditions. Oxidation rates measured by release of SO4-S to solution decreased with increasing application rate. Leachate SO4-S from soils amended with 1.0 to 3.0 g kg-1 CaSO3 increased over a 21 to 28 d period before reaching a plateau. At 4 g kg-1, maximum SO4-S release was delayed until Week 7. Oxidation and release of SO4-S from soil amended with 3.0 g kg-1 calcium sulfite increased markedly with decreasing soil pH. After only 3 d incubation, the concentrations of SO4-S in aqueous leachates were 77, 122, 170, 220, and 229 mg L-1 for initial soil pH values of 7.8, 6.5, 5.5, 5.1, and 4.0, respectively. At an initial soil pH value of 4.0, oxidation/dissolution did not increase much after 3 d. At higher pH values, oxidation was maximized after 21 d. These results suggest that autumn surface applications of calcium sulfite in no-till systems should permit ample time for oxidation/dissolution reactions to occur without introducing biocidal effects related to oxygen scavenging. Soil and annual crops can thus benefit from additions of soluble Ca and SO4 if calcium sulfite is applied in advance of spring planting. PMID:17215239

  14. Printability of calcium phosphate: calcium sulfate powders for the application of tissue engineered bone scaffolds using the 3D printing technique.

    PubMed

    Zhou, Zuoxin; Buchanan, Fraser; Mitchell, Christina; Dunne, Nicholas

    2014-05-01

    In this study, calcium phosphate (CaP) powders were blended with a three-dimensional printing (3DP) calcium sulfate (CaSO4)-based powder and the resulting composite powders were printed with a water-based binder using the 3DP technology. Application of a water-based binder ensured the manufacture of CaP:CaSO4 constructs on a reliable and repeatable basis, without long term damage of the printhead. Printability of CaP:CaSO4 powders was quantitatively assessed by investigating the key 3DP process parameters, i.e. in-process powder bed packing, drop penetration behavior and the quality of printed solid constructs. Effects of particle size, CaP:CaSO4 ratio and CaP powder type on the 3DP process were considered. The drop penetration technique was used to reliably identify powder formulations that could be potentially used for the application of tissue engineered bone scaffolds using the 3DP technique. Significant improvements (p<0.05) in the 3DP process parameters were found for CaP (30-110 ?m):CaSO4 powders compared to CaP (<20 ?m):CaSO4 powders. Higher compressive strength was obtained for the powders with the higher CaP:CaSO4 ratio. Hydroxyapatite (HA):CaSO4 powders showed better results than beta-tricalcium phosphate (?-TCP):CaSO4 powders. Solid and porous constructs were manufactured using the 3DP technique from the optimized CaP:CaSO4 powder formulations. High-quality printed constructs were manufactured, which exhibited appropriate green compressive strength and a high level of printing accuracy. PMID:24656346

  15. Iron concentration, bioavailability, and nutritional quality of polished rice affected by different forms of foliar iron fertilizer.

    PubMed

    He, Wanling; Shohag, M J I; Wei, Yanyan; Feng, Ying; Yang, Xiaoe

    2013-12-15

    The present study compared the effects of four different forms of foliar iron (Fe) fertilizers on Fe concentration, bioavailability and nutritional quality of polished rice. The results showed that foliar fertilisation at the anthesis stage was an effective way to promote Fe concentration and bioavailability of polished rice, especially in case of DTPA-Fe. Compared to the control, foliar application of DTPA-Fe increased sulphur concentration and the nutrition promoter cysteine content, whereas decreased phosphorus concentration and the antinutrient phytic acid content of polished rice, as a result increased 67.2% ferrtin formation in Caco-2 cell. Moreover, foliar DTPA-Fe application could maintain amylase, protein and minerals quality of polished rice. According to the current study, DTPA-Fe is recommended as an excellent foliar Fe form for Fe biofortification program. PMID:23993594

  16. Synthesis and characterization of bioresorbable calcium phosphosilicate nanocomposite particles for fluorescence imaging and biomedical applications

    NASA Astrophysics Data System (ADS)

    Morgan, Thomas T.

    Organically doped calcium phosphosilicate nanoparticles (CPSNPs) were developed and characterized, driven by the need for non-toxic vectors for drug delivery and fluorescence biological imaging applications. In particular, advancement in drug delivery for the chemotherapeutic treatment of cancers is required to increase drug efficacy and improve patient quality of life. Additionally, brighter and more photostable fluorophores are needed to meet demands for improved sensitivity and experimental diversity, which may lead to improvements in early detection of solid tumors and advancement in understanding of biological processes. A literature survey on the state of the field for nanoparticle based biological fluorescence imaging and drug delivery is presented in Chapter 1. Chapter 2 focuses on the characterization techniques used in this work. The development and optical characterization of 20-40 nm diameter, citrate functionalized Cy3 amidite doped calcium phosphosilicate nanoparticles (Cy3 CPSNPs) for in vitro fluorescence imaging is outlined in Chapters 3 and 4, respectively. In particular, sodium citrate was used to functionalize the surface and provide electrosteric dispersion of these particles. CPSNPs stabilized with sodium citrate routinely exhibited highly negative zeta potentials greater than -25 mV in magnitude. Furthermore, the fluorescence quantum yield of the encapsulated fluorophore was improved by more than 4.5-fold when compared to the unencapsulated dye. The bioimaging and drug delivery capability of CPSNPs was explored. Cy3 CPSNPs dissolved quickly in the acidic environment experienced during endocytosis, releasing the encapsulated fluorophore. This is consistent with solution phase experiments that show the particles are dissolved at pH 5. CPSNPs loaded with fluorescein and a hydrophobic growth inhibitor, ceramide C6, proved the ability to simultaneously image and delivery of the hydrophobic drug to cells in vitro. Chapter 5 examined the colloidal stability of citrate and polyethylene glycol (PEG) functionalized CPSNPs in 70 volume % ethanol/30% water, both experimentally using TEM and theoretically using DLVO and polymeric steric dispersion theories. There are three basic mechanisms for colloidal stability for macroscopic suspensions (i.e., for particulate diameters down to ˜100nm), metastable electrostatic in which some finite degree of agglomeration continuously takes place because a finite energy barrier against agglomeration; and electrosteric and steric mechanisms in which infinitely high potential energy barriers toward agglomeration are present leading to thermodynamically stable suspensions. One of the fundamental issues addressed in this chapter was whether the mechanisms of electrosteric or steric dispersion, based on relatively large adsorbed polyelectrolytes for macroscopic size particulates, scales with particles in the range of ˜40 nm diameter such that a small, charged organic molecule such as citrate provides the thermodynamic colloidal stability of electrosteric mechanisms as suggested by preliminary theoretical calculations. The particle diameter-number distributions for as-prepared and after drying (at 25°C) and redispersion were used as metrics for thermodynamic colloidal stability. How efficiently particles redispersed after drying and reintroduction into the 70:30 ethanol:water solvent was used as the primary metric for whether the metastable electrostatic mechanism or thermodynamically stable electrosteric or steric approaches were responsible for the robust dispersion experimentally observed in the colloids. These experiments found that, even with the thin electrosteric layer provided by the adsorbed citrate, particles were electrosterically dispersed, and were unagglomerated when dried under argon and redispersed. Preliminary work outlining the synthesis and characterization of silver core, calcium phosphosilicate shell nanoparticles for surface plasmon coupled emission and metal enhanced fluorescence applications is discussed in Chapter 6. Thin (2-5 nm) calcium phosphosilicate shells were formed around agglomerated silver cores in the presence of 8-Methoxypyrene-1,3,6-trisulfonic acid trisodium salt (MPTS). Calcium phosphosilicate shells were consistently formed after 72 hours in the presence of 5x10-5 M CaCl2, 3x10 -5 M Na2HPO4, 3x10-6 M Na 2SiO3, and silver core nanoparticles prepared by citrate reduction in aqueous solution. However, the particles synthesized were agglomerated, resulting in a loss of the plasmon resonance peak, and the shells prepared were not thick enough to provide sufficient separation of the fluorophore from the surface to prevent quenching and allow plasmon resonance enhanced fluorescence. (Abstract shortened by UMI.)

  17. One-step bulk preparation of calcium carbonate nanotubes and its application in anticancer drug delivery.

    PubMed

    Tang, Jing; Sun, Dong-Mei; Qian, Wen-Yu; Zhu, Rong-Rong; Sun, Xiao-Yu; Wang, Wen-Rui; Li, Kun; Wang, Shi-Long

    2012-06-01

    Bulk fabrication of ordered hollow structural particles (HSPs) with large surface area and high biocompatibility simultaneously is critical for the practical application of HSPs in biosensing and drug delivery. In this article, we describe a smart approach for batch synthesis of calcium carbonate nanotubes (CCNTs) based on supported liquid membrane (SLM) with large surface area, excellent structural stability, prominent biocompatibility, and acid degradability. The products were characterized by transmission electron micrograph, X-ray diffraction, Fourier transform infrared spectra, UV-vis spectroscopy, zeta potential, and particle size distribution. The results showed that the tube-like structure facilitated podophyllotoxin (PPT) diffusion into the cavity of hollow structure, and the drug loading and encapsulation efficiency of CCNTs for PPT are as high as 38.5 and 64.4 wt.%, respectively. In vitro drug release study showed that PPT was released from the CCNTs in a pH-controlled and time-dependent manner. The treatment of HEK 293T and SGC 7901 cells demonstrated that PPT-loaded CCNTs were less toxic to normal cells and more effective in antitumor potency compared with free drugs. In addition, PPT-loaded CCNTs also enhanced the apoptotic process on tumor cells compared with the free drugs. This study not only provides a new kind of biocompatible and pH-sensitive nanomaterial as the feasible drug container and carrier but more importantly establishes a facile approach to synthesize novel hollow structural particles on a large scale based on SLM technology. PMID:22351100

  18. Biofortification and Bioavailability of Rice Grain Zinc as Affected by Different Forms of Foliar Zinc Fertilization

    PubMed Central

    Yang, Xiaoe

    2012-01-01

    Background Zinc (Zn) biofortification through foliar Zn application is an attractive strategy to reduce human Zn deficiency. However, little is known about the biofortification efficiency and bioavailability of rice grain from different forms of foliar Zn fertilizers. Methodology/Principal Findings Four different Zn forms were applied as a foliar treatment among three rice cultivars under field trial. Zinc bioavailability was assessed by in vitro digestion/Caco-2 cell model. Foliar Zn fertilization was an effective agronomic practice to promote grain Zn concentration and Zn bioavailability among three rice cultivars, especially, in case of Zn-amino acid and ZnSO4. On average, Zn-amino acid and ZnSO4 increased Zn concentration in polished rice up to 24.04% and 22.47%, respectively. On average, Zn-amino acid and ZnSO4 increased Zn bioavailability in polished rice up to 68.37% and 64.43%, respectively. The effectiveness of foliar applied Zn-amino acid and ZnSO4 were higher than Zn-EDTA and Zn-Citrate on improvement of Zn concentration, and reduction of phytic acid, as a results higher accumulation of bioavailable Zn in polished rice. Moreover, foliar Zn application could maintain grain yield, the protein and minerals (Fe and Ca) quality of the polished rice. Conclusions Foliar application of Zn in rice offers a practical and useful approach to improve bioavailable Zn in polished rice. According to current study, Zn-amino acid and ZnSO4 are recommended as excellent foliar Zn forms to ongoing agronomic biofortification. PMID:23029003

  19. Effect of calcium silicate slag application on radium-226 concentrations in plant tissues

    SciTech Connect

    Mortvedt, J.J.

    1986-01-01

    A greenhouse pot experiment was conducted to determine if plants absorb Ra from slag applied to soil. Slag at rates equivalent to 0 and 22 mt/ha was mixed with Mountview silt loam (Typic Paleudults) limed to pH 5.8 and 7.2. Three clippings each of fescue (Festuca arundiancea Schreb.), and Swiss chard (Beta vulgaris L.), and one harvest of wheat (Triticum aestivum L.) for grain and straw were grown on separate series of treated soil, and plant samples were analyzed for radioactivity due to /sup 226/Ra uptake. Samples of sugarcane (Saccharum officinarum L.) forage and extracted juice from field experiments in Florida testing this slage as a Si source also were analyzed for radioactivity. Dry forage yields of fescue and wheat were not affected by slag applications, but those of Swiss chard were somewhat higher on slag-treated soil at pH 5.8. Wheat grain and straw yields were higher on soil at pH 7.2 than at pH 5.8 regardless of slag treatment. Uptake of /sup 226/Ra by fescue forage and wheat grain and straw was not affected by slag application. Concentrations of /sup 226/Ra were similar in forage and extracted juice from untreated sugarcane or that treated with slag at rates up to 5.6 mt/ha. These results suggest that plant uptake of radionuclides is negligible from calcium silicate slag applied at the recommended rates for liming acid soils or as a source of Si for sugarcane.

  20. Synthesis of calcium carbonate nanocrystals and their potential application as vessels for drug delivery

    NASA Astrophysics Data System (ADS)

    Vergaro, Viviana; Carata, Elisabetta; Panzarini, Elisa; Baldassare, Francesca; Dini, Luciana; Ciccarella, Giuseppe

    2015-06-01

    Pure and stable calcium carbonate (CaCO3) nanocrystals were synthesized by spray drying method. We exploited the opportunity to use them as vessels for drug delivery studying the biocompatibility and the internalization in HeLa cells.

  1. Isolation of calcium-binding proteins on selective adsorbents. Application to purification of bovine calmodulin.

    PubMed

    Chaga, G S; Ersson, B; Porath, J O

    1996-05-01

    We report the fractionation of calcium-binding proteins using immobilized metal ion affinity chromatography (IMAC) with hard metal ions. Various hard metal ions (Mn2+, La3+, Nd3+, Eu(3 were immobilized on cross-linked agarose substituted with Tris(carboxymethyl)ethylenediamine (TED) and used as an adsorbent. After systematic studies, europium was selected for further work on the fractionation of calcium-binding proteins. It was found that the presence of Ca2+ in the sample and the solvent strongly promoted the adsorption and selectivity. Selective elution was accomplished in stepwise mode by the addition of calcium chelators such as malonate, citrate and phosphate. Calmodulin of high purity was isolated from a crude extract. Similar behavior of other calcium-binding proteins indicates that the reported chromatographic procedure can be generally applied to such proteins. PMID:8653201

  2. The preparation of calcium superoxide for air breathing and scrubbing applications

    NASA Technical Reports Server (NTRS)

    Ballou, E. V.; Wood, P. C.; Spitze, L. A.; Wydeven, T.

    1976-01-01

    There is interest in the preparation of high-purity calcium superoxide as an oxygen source for breathing apparatus because both the available oxygen and the capacity for carbon dioxide removal, per unit weight of superoxide, are higher than that of a number of other chemical oxygen sources. A review of earlier findings shows that the general method used by Vol'nov and coworkers for the decomposition of calcium peroxide diperoxyhydrate can yield preparations containing more than 58.4% calcium superoxide maximum predicted for an equimolar disproportionation reaction. The decomposition of solid calcium peroxide diperoxyhydrate is studied using an apparatus that allows good control of the critical reaction parameters. The removal of water from decomposing calcium peroxide diperoxyhydrate, before the same water has an opportunity to back react with the calcium superoxide formed in the reaction, constitutes the rationale of the experiments. Even with allowance for the anomalies observed in the analytical results, the yields appear to be in the 65+ percent range, and optimization of the experimental variables is still being pursued.

  3. Effect of Maize Hybrid and Foliar Fungicides on Yield Under Low Foliar Disease Severity Conditions.

    PubMed

    Mallowa, Sally O; Esker, Paul D; Paul, Pierce A; Bradley, Carl A; Chapara, Venkata R; Conley, Shawn P; Robertson, Alison E

    2015-08-01

    Foliar fungicide use in the U.S. Corn Belt increased in the last decade; however, questions persist pertaining to its value and sustainability. Multistate field trials were established from 2010 to 2012 in Illinois, Iowa, Ohio, and Wisconsin to examine how hybrid and foliar fungicide influenced disease intensity and yield. The experimental design was in a split-split plot with main plots consisting of hybrids varying in resistance to gray leaf spot (caused by Cercospora zeae-maydis) and northern corn leaf blight (caused by Setosphaera turcica), subplots corresponding to four application timings of the fungicide pyraclostrobin, and sub-subplots represented by inoculations with either C. zeae-maydis, S. turcica, or both at two vegetative growth stages. Fungicide application (VT/R1) significantly reduced total disease severity relative to the control in five of eight site-years (P<0.05). Disease was reduced by approximately 30% at Wisconsin in 2011, 20% at Illinois in 2010, 29% at Iowa in 2010, and 32 and 30% at Ohio in 2010 and 2012, respectively. These disease severities ranged from 0.2 to 0.3% in Wisconsin in 2011 to 16.7 to 22.1% in Illinois in 2010. The untreated control had significantly lower yield (P<0.05) than the fungicide-treated in three site-years. Fungicide application increased the yield by approximately 6% at Ohio in 2010, 5% at Wisconsin in 2010 and 6% in 2011. Yield differences ranged from 8,403 to 8,890 kg/ha in Wisconsin 2011 to 11,362 to 11,919 kg/ha in Wisconsin 2010. Results suggest susceptibility to disease and prevailing environment are important drivers of observed differences. Yield increases as a result of the physiological benefits of plant health benefits under low disease were not consistent. PMID:25760523

  4. Water stress and foliar boron application altered seed nutrition in near-isogenic cotton lines expressing fuzzy and fuzzless seed phenotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research, conducted under well-watered conditions without fertilizer application showed that fuzzy cottonseed trait resulted in cottonseed nutrient differences between fuzzy (F) and fuzzless (N) cottonseed, probably due to the involvement of carbon metabolism and energy use in fuzz fiber de...

  5. Characterization of nickel-doped biphasic calcium phosphate/graphene nanoplatelet composites for biomedical application.

    PubMed

    Baradaran, S; Moghaddam, E; Nasiri-Tabrizi, Bahman; Basirun, W J; Mehrali, M; Sookhakian, M; Hamdi, M; Alias, Y

    2015-04-01

    The effect of the addition of an ionic dopant to calcium phosphates for biomedical applications requires specific research due to the essential roles played in such processes. In the present study, the mechanical and biological properties of Ni-doped hydroxyapatite (HA) and Ni-doped HA mixed with graphene nanoplatelets (GNPs) were evaluated. Ni (3wt.% and 6wt.%)-doped HA was synthesized using a continuous precipitation method and calcined at 900°C for 1h. The GNP (0.5-2wt.%)-reinforced 6% Ni-doped HA (Ni6) composite was prepared using rotary ball milling for 15h. The sintering process was performed using hot isostatic pressing at processing conditions of 1150°C and 160MPa with a 1-h holding time. The results indicated that the phase compositions and structural features of the products were noticeably affected by the Ni and GNPs. The mechanical properties of Ni6 and 1.5Ni6 were increased by 55% and 75% in hardness, 59% and 163% in fracture toughness and 120% and 85% in elastic modulus compared with monolithic HA, respectively. The in-vitro biological behavior was investigated using h-FOB osteoblast cells in 1, 3 and 5days of culture. Based on the osteoblast results, the cytotoxicity of the products was indeed affected by the Ni doping. In addition, the effect of GNPs on the growth and proliferation of osteoblast cells was investigated in Ni6 composites containing different ratios of GNPs, where 1.5wt.% was the optimum value. PMID:25686995

  6. Exogenous application of calcium and silica alleviates cadmium toxicity by suppressing oxidative damage in rice seedlings.

    PubMed

    Srivastava, Rajneesh Kumar; Pandey, Poonam; Rajpoot, Ritika; Rani, Anjana; Gautam, Arti; Dubey, R S

    2015-07-01

    The present study was undertaken to examine the possible roles of calcium (Ca(2+)) and silica (Si) in protection against oxidative damage due to Cd(2+) toxicity in rice (Oryza sativa L.) seedlings grown in hydroponics. Rice seedlings raised for 12 days in hydroponics containing Cd(NO3)2 (75 μM) showed reduced growth; increase in the level of reactive oxygen species (ROS) (O2 (·-) and H2O2), thiobarbituric acid reactive substances (TBARSs) and protein carbonylation; and increase in the activity of antioxidant enzymes-superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPX) compared to untreated controls. Exogenously added Ca(2+) (2 mM) and Si (200 μM) significantly alleviated negative effect of Cd(2+) by restoration of growth of the seedlings, suppression of Cd(2+) uptake and restoration of root plasma membrane integrity. The levels of O2 (·-), H2O2, lipid peroxidation and protein carbonyls were much lower when Ca(2+) and Si were added in the growth medium along with Cd(2+) as compared to Cd-alone-treated seedlings. Ca(2+) and Si lowered Cd-induced increase in SOD, GPX and APX activities while they elevated Cd-induced decline in CAT activity. Using histochemical staining of O2 (·-) and H2O2 in leaf tissues, it was further confirmed that added Ca(2+) and Si suppressed Cd-induced accumulation of O2 (·-) and H2O2 in the leaves. The results suggest that exogenous application of Ca(2+) and Si appears to be advantageous for rice plants in alleviating Cd(2+) toxicity effects by reducing Cd(2+) uptake, decreasing ROS production and suppressing oxidative damage. The observations indicate that Ca(2+) and Si treatments can help in reducing Cd(2+) toxicity in rice plants. PMID:25413289

  7. Propagating calcium waves initiated by local caffeine application in rat ventricular myocytes.

    PubMed Central

    Trafford, A W; Lipp, P; O'Neill, S C; Niggli, E; Eisner, D A

    1995-01-01

    1. Caffeine was applied locally to one region of a resting cell via an extracellular pipette while simultaneously imaging the concentrations of intracellular calcium ([Ca2+]i) and intracellular caffeine ([caffeine]i). 2. Local application of caffeine produced a rise of [caffeine]i which was confined to the region of the cell near the pipette. There was also a local increase of [Ca2+]i which then, in most resting cells, propagated along the cell as a linear Ca2+ wave. The initial magnitude of the rise of [Ca2+]i was greater than that of the electrically stimulated Ca2+ transient. 3. As the wave of increase of [Ca2+]i propagated along the cell it decreased in both amplitude and velocity in cells that had not been treated to elevate the cellular Ca2+ load. 4. In some cells the caffeine response did not propagate significantly. In these cases an increase of the cellular Ca2+ load enabled caffeine-induced Ca2+ wave propagation along the entire cell length without significant decay in amplitude and velocity. 5. Previous work has shown that an electrically evoked local systolic Ca2+ transient does not propagate. The fact that the caffeine-evoked response does propagate and the correlation between decay of amplitude and velocity suggest that the transient has to be a certain size before it can propagate. It is suggested that one of the factors which favour propagation of waves under conditions of elevated sarcoplasmic reticulum Ca2+ content is the increased release of Ca2+. Images Figure 1 Figure 2 Figure 4 PMID:8847628

  8. INOCULATION AND GROWTH WITH FOLIAR PATHOGENIC FUNGI

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes methods for evaluating responses of Medicago truncatula to foliar plant-pathogenic fungi. Growth of plants, preparation of inoculum, incubation conditions, and disease assessment are described for five necrotrophic pathogens (Ascochyta lentis, Ascochyta rabiei, Colletotrichum ...

  9. Calcium bioavailability of vegetarian diets in rats: potential application in a bioregenerative life-support system

    NASA Technical Reports Server (NTRS)

    Nickel, K. P.; Nielsen, S. S.; Smart, D. J.; Mitchell, C. A.; Belury, M. A.

    1997-01-01

    Calcium bioavailability of vegetarian diets containing various proportions of candidate crops for a controlled ecological life-support system (CELSS) was determined by femur 45Ca uptake. Three vegetarian diets and a control diet were labeled extrinsically with 45Ca and fed to 5-wk old male rats. A fifth group of rats fed an unlabeled control diet received an intraperitoneal (IP) injection of 45Ca. There was no significant difference in mean calcium absorption of vegetarian diets (90.80 +/- 5.23%) and control diet (87.85 +/- 5.25%) when calculated as the percent of an IP dose. The amounts of phytate, oxalate, and dietary fiber in the diets did not affect calcium absorption.

  10. The impact of foliar boron sprays on reproductive biology and seed quality of black gram.

    PubMed

    Pandey, Nalini; Gupta, Bhavana

    2013-01-01

    An experiment was conducted under glass house condition to study the effect of foliar application of boron (B) on reproductive biology and seed quality of black gram (Vigna mungo). Black gram (V. mungo L. var. DPU-88-31) was grown under controlled sand culture condition at deficient and sufficient B levels. After 32 days of sowing B deficient plants were sprayed with three concentrations of B (0.05%, 0.1% and 0.2% borax) at three different stages of reproductive development, i.e. prior to flowering, initiation of bud formation and after bud formation. Deficient B supply decreased the anther and pollen size, pollen tube growth, pollen viability as well as stigmatic receptivity which were increased by foliar B application. Foliar spray at all the three concentrations and at all stages increased the yield parameters like number of pods, pod size and number of seeds formed per plant. Foliar B application also improved the seed yield and seed quality in terms of storage seed proteins (albumin, globulin, glutenin and prolamin) and carbohydrates (sugars and starch) in black gram. The foliar application of B in appropriate doses (particularly 0.1%) after bud formation made quantitative and qualitative improvement in seed yield of black gram by supplementing additional/critical B requirements for reproductive development. PMID:22947393

  11. Calcium Carbonate

    MedlinePLUS

    Calcium carbonate is a dietary supplement used when the amount of calcium taken in the diet is not ... for healthy bones, muscles, nervous system, and heart. Calcium carbonate also is used as an antacid to relieve ...

  12. Influence of soil pH and application rate on the oxidation of calcium sulfite derived from flue gas desulfurization

    SciTech Connect

    Lee, Y.B.; Bigham, J.M.; Dick, W.A.; Jones, E.S.; Ramsier, C.

    2007-01-15

    Calcium sulfite hemihydrate (CaSO{sub 3} {center_dot} 0.5H{sub 2}O), a common byproduct of coal-fired utilities, is fairly insoluble and can decompose to release toxic SO{sub 2} under highly acidic soil conditions; however, it can also oxidize to form gypsum. The objective of this study was to examine the effects of application rate and soil pH on the oxidation of calcium sulfite under laboratory conditions. Oxidation rates measured by release of SO{sub 4}-S to solution decreased with increasing application rate. Leachate SO{sub 4}-S from soils amended with 1.0 to 3.0 g kg{sup -1} CaSO{sub 3} increased over a 21 to 28 d period before reaching a plateau. At 4 g kg{sup -1}, maximum SO{sub 4}-S release was delayed until Week 7. Oxidation and release of SO{sub 4}-S from soil amended with 3.0 g kg{sup -1} calcium sulfite increased markedly with decreasing soil pH. After only 3 d incubation, the concentrations of SO{sub 4}-S in aqueous leachates were 77, 122, 1709 220, and 229 mg L{sup -1} for initial soil pH values of 7.8, 6.5, 5.5, 5.1, and 4.0, respectively. At an initial soil pH value of 4.0, oxidation/dissolution did not increase much after 3 d. At higher pH values, oxidation was maximized after 21 d. These results suggest that autumn surface applications of calcium sulfite in no-till systems should permit ample time for oxidation/dissolution reactions to occur without introducing biocidal effects related to oxygen scavenging. Soil and annual crops can thus benefit from additions of soluble Ca and SO{sub 4} if calcium sulfite is applied in advance of spring planting.

  13. Calcium Test

    MedlinePLUS

    ... dietary calcium Decreased levels of vitamin D Magnesium deficiency Increased levels of phosphorus Acute inflammation of the pancreas ( pancreatitis ) Renal failure Urinary calcium levels may be affected by ...

  14. Application of pulsed spark discharge for calcium carbonate precipitation in hard water.

    PubMed

    Yang, Yong; Kim, Hyoungsup; Starikovskiy, Andrey; Fridman, Alexander; Cho, Young I

    2010-06-01

    The effect of underwater pulsed spark discharge on the precipitation of dissolved calcium ions was investigated in the present study. Water samples with different calcium hardness were prepared by continuous evaporation of tap water using a laboratory cooling tower. It was shown that the concentration of calcium ions dropped by 20-26% after 10-min plasma treatment, comparing with no drop for untreated cases. A laser particle counting method demonstrated that the total number of solid particles suspended in water increased by over 100% after the plasma treatment. The morphology and the crystal form of the particles were identified by both scanning electron microscopy and X-ray diffraction. Calcite with rhombohedron morphology was observed for plasma treated cases, comparing with the round structure observed for no-treatment cases. It was hypothesized that the main mechanisms for the plasma-assisted calcium carbonate precipitation might include electrolysis, local heating in the vicinity of plasma channel and a high electric field at the tip of plasma streamers, inducing structural changes in the electric double layer of hydrated ions. PMID:20494397

  15. Ion Association versus Ion Interaction Models in Examining Electrolyte Solutions: Application to Calcium Hydroxide Solubility Equilibrium

    ERIC Educational Resources Information Center

    Menéndez, M. Isabel; Borge, Javier

    2014-01-01

    The heterogeneous equilibrium of the solubility of calcium hydroxide in water is used to predict both its solubility product from solubility and solubility values from solubility product when inert salts, in any concentration, are present. Accepting the necessity of including activity coefficients to treat the saturated solution of calcium…

  16. Process for decontaminating radioactive liquids using a calcium cyanamide-containing composition. [Patent application

    DOEpatents

    Silver, G.L.

    1980-09-24

    The present invention provides a process for decontaminating a radioactive liquid containing a radioactive element capable of forming a hydroxide. This process includes the steps of contacting the radioactive liquid with a decontaminating composition and separating the resulting radioactive sludge from the resulting liquid. The decontaminating composition contains calcium cyanamide.

  17. Foliar washoff of pesticides by rainfall

    SciTech Connect

    Cohen, M.L.; Steinmetz, W.D.

    1986-05-01

    Several insecticides were subjected to simulated rainfall after application on octadecylsilanized/trimethylsilanized glass or foliar surfaces. Flucythrinate (cyano(3-phenoxy-phenyl)methyl 4-(difluoromethoxy)-..cap alpha..-(1-methylethyl)-benzeneacetate), fenvalerate ((RS)-cyano(3-phenoxyphenyl)methyl (RS)-4-chloro-..cap alpha..-(1-methylethyl)benzene-acetate), and azinphosmethyl (O,O-dimethyl S-((4-oxo-1,2,3-benzotriazin-3(4H)-yl)-methyl) phosphorodithioate) showed 35-61% washoff by 25 mm of simulated rainfall, while methyl parathion (O,O-dimethyl O-4-nitrophenyl phosphorothioate) loss was over 90% of that applied. Washoff was initially rapid, but reached a secondary slower phase. Chlordimeform (N'-(4-chloro-2-methylphenyl)-N,N-dimethylmethanimidamide) and diazinon (O,O-diethyl O-(6-methyl-2-(1-methylethyl)-4-pyrimidinyl) phosphorothioate), in addition to exhibiting rapid volatilization, suffered nearly complete washoff by 25 mm of simulated rainfall. The use of octadecylsilanized/trimethylsilanized glass slides as a model for cotton leaf surfaces yielded results similar to those seen on actual cotton leaves (Gossypium hirsutum L.). 34 references, 4 tables.

  18. Reinforcement of calcium phosphate cement with multi-walled carbon nanotubes and bovine serum albumin for injectable bone substitute applications.

    PubMed

    Chew, Kean-Khoon; Low, Kah-Ling; Sharif Zein, Sharif Hussein; McPhail, David S; Gerhardt, Lutz-Christian; Roether, Judith A; Boccaccini, Aldo R

    2011-04-01

    This paper presents the development of novel alternative injectable calcium phosphate cement (CPC) composites for orthopaedic applications. The new CPC composites comprise ?-tri-calcium phosphate (?-TCP) and di-calcium phosphate anhydrous (DCPA) mixed with bovine serum albumin (BSA) and incorporated with multi-walled carbon nanotubes (MWCNTs) or functionalized MWCNTs (MWCNTs-OH and MWCNTs-COOH). Scanning electron microscopy (SEM), compressive strength tests, injectability tests, Fourier transform infrared spectroscopy and X-ray diffraction were used to evaluate the properties of the final products. Compressive strength tests and SEM observations demonstrated particularly that the concomitant admixture of BSA and MWCNT improved the mechanical properties, resulting in stronger CPC composites. The presence of MWCNTs and BSA influenced the morphology of the hydroxyapatite (HA) crystals in the CPC matrix. BSA was found to act as a promoter of HA growth when bounded to the surface of CPC grains. MWCNT-OH-containing composites exhibited the highest compressive strengths (16.3MPa), being in the range of values for trabecular bone (2-12MPa). PMID:21316621

  19. Combined effect of CO2 enrichment and foliar application of salicylic acid on the production and antioxidant activities of anthocyanin, flavonoids and isoflavonoids from ginger

    PubMed Central

    2012-01-01

    Background The increase in atmospheric CO2 concentration caused by climate change and agricultural practices is likely to affect biota by producing changes in plant growth, allocation and chemical composition. This study was conducted to evaluate the combined effect of the application of salicylic acid (SA, at two levels: 0 and 10-3 M) and CO2 enrichment (at two levels: 400 and 800 ?molmol?1) on the production and antioxidant activities of anthocyanin, flavonoids and isoflavonoids from two Malaysian ginger varieties, namely Halia Bentong and Halia Bara. Methods High-performance liquid chromatography (HPLC) with photodiode array detection and mass spectrometry was employed to identify and quantify the flavonoids and anthocyanins in the ginger extracts. The antioxidant activity of the leaf extracts was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and thiobarbituric acid (TBA) assays. The substrate specificity of chalcone synthase, the key enzyme for flavonoid biosynthesis, was investigated using the chalcone synthase (CHS) assay. Results CO2 levels of 800 ?molmol?1 significantly increased anthocyanin, rutin, naringenin, myricetin, apigenin, fisetin and morin contents in ginger leaves. Meanwhile, the combined effect of SA and CO2 enrichment enhanced anthocyanin and flavonoid production compared with single treatment effects. High anthocyanin content was observed in H Bara leaves treated with elevated CO2 and SA. The highest chalcone synthase (CHS) activity was observed in plants treated with SA and CO2 enrichment. Plants not treated with SA and kept under ambient CO2 conditions showed the lowest CHS activity. The highest free radical scavenging activity corresponded to H Bara treated with SA under high CO2 conditions, while the lowest activity corresponded to H Bentong without SA treatment and under atmospheric CO2 levels. As the level of CO2 increased, the DPPH activity increased. Higher TBA activity was also recorded in the extracts of H Bara treated with SA and grown under high CO2 conditions. Conclusions The biological activities of both ginger varieties were enhanced when the plants were treated with SA and grown under elevated CO2 concentration. The increase in the production of anthocyanin and flavonoids in plants treated with SA could be attributed to the increase in CHS activity under high CO2 levels. PMID:23176249

  20. Polyfunctional bioceramics based on calcium phosphate and M-type hexagonal ferrite for medical applications

    NASA Astrophysics Data System (ADS)

    Tkachenko, M. V.; Ol'khovik, L. P.; Kamzin, A. S.; Keshri, S.

    2014-01-01

    Magnetic biologically active ceramics based on calcium phosphate with a content of M-type hexagonal ferrite (HF) particles varying from 10 to 50 wt % has been synthesized and characterized. It has been found that the ceramics synthesized consists of a biocompatible carbonated hydroxyapatite (CHA) with the matrix containing M-type HF particles, leading to the magnetic characteristics of the ceramics synthesized being significantly higher than those of iron-oxide-modified bioglass ceramics used in medicine.

  1. Europium-doped amorphous calcium phosphate porous nanospheres: preparation and application as luminescent drug carriers

    PubMed Central

    2011-01-01

    Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP)/polylactide-block-monomethoxy(polyethyleneglycol) hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL) function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP) porous nanospheres is achieved (126.7 m2/g). PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time (ln(t)). The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated. PMID:21711603

  2. Europium-doped amorphous calcium phosphate porous nanospheres: preparation and application as luminescent drug carriers

    NASA Astrophysics Data System (ADS)

    Chen, Feng; Zhu, Ying-Jie; Zhang, Kui-Hua; Wu, Jin; Wang, Ke-Wei; Tang, Qi-Li; Mo, Xiu-Mei

    2011-12-01

    Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP)/polylactide-block-monomethoxy(polyethyleneglycol) hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL) function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP) porous nanospheres is achieved (126.7 m2/g). PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time ( ln( t)). The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated.

  3. Mechanical and physical properties of calcium silicate/alumina composite for biomedical engineering applications.

    PubMed

    Shirazi, F S; Mehrali, M; Oshkour, A A; Metselaar, H S C; Kadri, N A; Abu Osman, N A

    2014-02-01

    The focus of this study is to investigate the effect of Al2O3 on α-calcium silicate (α-CaSiO3) ceramic. α-CaSiO3 was synthesized from CaO and SiO2 using mechanochemical method followed by calcinations at 1000°C. α-CaSiO3 and alumina were grinded using ball mill to create mixtures, containing 0-50w% of Al2O3 loadings. The powders were uniaxially pressed and followed by cold isostatic pressing (CIP) in order to achieve greater uniformity of compaction and to increase the shape capability. Afterward, the compaction was sintered in a resistive element furnace at both 1150°C and 1250°C with a 5h holding time. It was found that alumina reacted with α-CaSiO3 and formed alumina-rich calcium aluminates after sintering. An addition of 15wt% of Al2O3 powder at 1250°C were found to improve the hardness and fracture toughness of the calcium silicate. It was also observed that the average grain sizes of α-CaSiO3 /Al2O3 composite were maintained 500-700nm after sintering process. PMID:24316872

  4. CALCIUM-INDUCED SUPRAMOLECULAR STRUCTURES IN THE CALCIUM CASEINATE SYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The molecular details deciphering the spontaneous calcium-induced protein aggregation process in the calcium caseinate system remain obscure. Understanding this complex process could lead to potential new applications of this important food ingredient. In this work, we studied calcium-induced supra...

  5. Characterization of a calcium-soluble protein fraction from yellow mustard (Sinapis alba) seed meal with potential application as an additive to calcium-rich drinks.

    PubMed

    Aluko, Rotimi E; Reaney, Martin; McIntosh, Tara; Ouellet, Franois; Katepa-Mupondwa, Felicitas

    2004-09-22

    A calcium-soluble protein isolate (CSPI) was prepared from the supernatant obtained after addition of 0.75 M calcium chloride to a pH 5.0 aqueous extract of yellow mustard (Sinapis alba) seed meal. Total amino acid analysis showed that the CSPI has significantly higher (p < 0.05) contents of glutamic acid + glutamine, cysteine, and proline when compared to the precipitated, calcium-insoluble proteins. Peptide mass fingerprinting of tryptic peptides of the major polypeptides by mass spectrometry indicated that the CSPI is composed mainly of cruciferin proteins with a contribution from napins (the major allergenic proteins of S. alba). The S. alba CSPI had significantly higher (p < 0.05) protein solubility and emulsion formation ability in the presence of 0.75 M calcium chloride when compared to similar isolates prepared from Brassica juncea (brown mustard) and soybean seed meals. We suggest that the S. alba CSPI could be used to prepare calcium-fortified high protein liquid products. However, the presence of allergenic proteins in this extract may limit its widespread food use. PMID:15366859

  6. Augmentation of Bone Tunnel Healing in Anterior Cruciate Ligament Grafts: Application of Calcium Phosphates and Other Materials

    PubMed Central

    Baxter, F. R.; Bach, J. S.; Detrez, F.; Cantournet, S.; Cort, L.; Cherkaoui, M.; Ku, D. N.

    2010-01-01

    Bone tunnel healing is an important consideration after anterior cruciate ligament (ACL) replacement surgery. Recently, a variety of materials have been proposed for improving this healing process, including autologous bone tissue, cells, artificial proteins, and calcium salts. Amongst these materials are calcium phosphates (CaPs), which are known for their biocompatibility and are widely commercially available. As with the majority of the materials investigated, CaPs have been shown to advance the healing of bone tunnel tissue in animal studies. Mechanical testing shows fixation strengths to be improved, particularly by the application of CaP-based cement in the bone tunnel. Significantly, CaP-based cements have been shown to produce improvements comparable to those induced by potentially more complex treatments such as biologics (including fibronectin and chitin) and cultured cells. Further investigation of CaP-based treatment in the bone tunnels during ACL replacement is therefore warranted in order to establish what improvements in healing and resulting clinical benefits may be achieved through its application. PMID:21350646

  7. Augmentation of bone tunnel healing in anterior cruciate ligament grafts: application of calcium phosphates and other materials.

    PubMed

    Baxter, F R; Bach, J S; Detrez, F; Cantournet, S; Corté, L; Cherkaoui, M; Ku, D N

    2010-01-01

    Bone tunnel healing is an important consideration after anterior cruciate ligament (ACL) replacement surgery. Recently, a variety of materials have been proposed for improving this healing process, including autologous bone tissue, cells, artificial proteins, and calcium salts. Amongst these materials are calcium phosphates (CaPs), which are known for their biocompatibility and are widely commercially available. As with the majority of the materials investigated, CaPs have been shown to advance the healing of bone tunnel tissue in animal studies. Mechanical testing shows fixation strengths to be improved, particularly by the application of CaP-based cement in the bone tunnel. Significantly, CaP-based cements have been shown to produce improvements comparable to those induced by potentially more complex treatments such as biologics (including fibronectin and chitin) and cultured cells. Further investigation of CaP-based treatment in the bone tunnels during ACL replacement is therefore warranted in order to establish what improvements in healing and resulting clinical benefits may be achieved through its application. PMID:21350646

  8. Surface microstructure and cell compatibility of calcium silicate and calcium phosphate composite coatings on Mg-Zn-Mn-Ca alloys for biomedical application.

    PubMed

    Du, Hui; Wei, Zunjie; Wang, Hongwei; Zhang, Erlin; Zuo, Lin; Du, Lianping

    2011-03-01

    A calcium silicate and calcium phosphate (CaSiO(3)/CaHPO(4)2H(2)O) composite coating was applied by a chemical reaction to Mg-Zn-Mn-Ca alloy to improve its biocompatiblity. The surface microstructure was observed by scanning electronic microscopy (SEM) and the surface bioactivity was assessed by a cell interaction experiment. SEM observation showed that a microporous layer was formed on the surface of Mg-Zn-Mn-Ca alloy. It was shown by XRD that the reaction layer was mainly composed of CaHPO(4)2H(2)O and a small amount of CaSiO(3). In vitro cell experiments indicated that osteoblasts showed good adhesion, high growth rates and proliferation characteristics on the coated Mg-Zn-Mn-Ca alloy, indicating that the surface cytocompatibility of Mg-Zn-Mn-Ca alloy was significantly improved by the calcium phosphate coating. PMID:21145712

  9. Economical Route to Produce High Seebeck Coefficient Calcium Cobaltate for Bulk Thermoelectric Applications

    SciTech Connect

    Selig, Jiri; Lin, Sidney; Lin, Hua-Tay; Johnson, D Ray; Wang, Hsin

    2011-01-01

    Phase pure calcium cobaltate (Ca1.24Co1.62O3.86) was prepared by Self-propagating High-temperature Synthesis (SHS) followed by a short post heat treatment. Prepared powders were characterized by XRD for phase purity, and SEM for particle size and distribution. Temperature histories at the center and on the surface of reaction pellet during the SHS process were monitored and recorded. Particles size of synthesized powders was reduced using a planetary mill to increase its specific surface area. Electrical conductivity, thermal conductivity and Seebeck coefficient of the prepared power were measured and figure of merit was reported.

  10. Applicability of the energy dispersive x-ray microanalysis for quantification of irregular calcium deposits on fruit and leaf cuticles.

    PubMed

    Hunsche, M; Noga, G

    2008-12-01

    In our studies, we evaluated the relation between CaCl(2) concentration and the scanning electron microscope-energy dispersive x-ray microanalysis parameters, net intensity, peak/background and standardized percentage of atoms and percentage of weight after application of single microdroplets on enzymatically isolated tomato fruit cuticles and apple seedling leaves. After analysis, the Ca/Cl ratio was calculated and the area ultimately covered with Ca and Cl within the droplet spread area determined. According to our findings, all evaluated parameters were influenced by both droplet volume and calcium chloride concentration, whereas Pearson's analysis revealed a strong correlation between net intensity and area ultimately covered by Ca or Cl, respectively. Simple linear regressions for net intensity, peak/background and Ca/Cl ratio showed variable determination coefficients (R(2)) ranging between 0.49 and 0.79. Multiple regression equations comprising net intensity, Ca/Cl ratio and deposit area were established to estimate the amount of calcium present on the cuticles. Equation slopes depended on droplet volumes, with determination coefficients of 0.89 and 0.81 for 0.5 and 1.0-microL droplets, respectively. The importance of the physicochemical properties of the spray solution was exploited in another study where a hydrophobic or a hydrophilic adjuvant was added to a 10 g L(-1) CaCl(2) solution, which was applied to apple seedling leaves. The addition of adjuvants increased values of net intensity and peak/background, which correlated significantly with the area covered by calcium. The importance of the methodology for studies on the interaction between leaf applied fertilizers (also extended to agrochemicals) and the characteristics of target surfaces is discussed. PMID:19094022

  11. Biomimetic calcium phosphate coating on Ti-7.5Mo alloy for dental application.

    PubMed

    Escada, A L A; Machado, J P B; Schneider, S G; Rezende, M C R Alves; Claro, A P R Alves

    2011-11-01

    Titanium and its alloys have been used as bone-replacement implants due to their excellent corrosion resistance and biocompatibility. However, a titanium coating is a bioinert material and cannot bond chemically to bone tissue. The objective of this work was to evaluate the influence of alkaline treatment and heat treatment on the formation of calcium phosphate layer on the surface of a Ti-7.5Mo alloy after soaking in simulated body fluid (SBF). Thirty six titanium alloy plates were assigned into two groups. For group I, samples were immersed in a 5.0-M NaOH aqueous solution at 80°C for 72 h, washed with distilled water and dried at 40°C for 24 h. For group II, after the alkaline treatment, samples were heat-treated at 600°C for 1 h in an electrical furnace in air. Then, all samples were immersed in SBF for 7 or 14 days to allow the formation of a calcium phosphate coating on the surface. The surfaces were characterized using SEM, EDS, AFM and contact angle measurements. PMID:21909642

  12. Bioactive calcium sulfate/magnesium phosphate cement for bone substitute applications.

    PubMed

    Yang, Guangyong; Liu, Jianli; Li, Fan; Pan, Zongyou; Ni, Xiao; Shen, Yue; Xu, Huazi; Huang, Qing

    2014-02-01

    A novel calcium sulfate/magnesium phosphate cement (CSMPC) composite was prepared and studied in the present work. The physical properties including the phases, the microstructures, the setting properties and the compressive strengths of the CSMPCs were studied. The bio-performances of the CSMPCs were comprehensively evaluated using in vitro simulated body fluid (SBF) method and in vitro cell culture. The dependence of the physical and chemical properties of the CSMPC on its composition and microstructure was studied in detail. It is found that the CSMPC composites exhibited mediate setting times (6-12 min) compared to the calcium sulfate (CS) and the magnesium phosphate cement (MPC). They showed an encapsulation structure in which the unconverted hexagonal prism CSH particles were embedded in the xerogel-like MPC matrix. The phase compositions and the mechanical properties of the CSMPCs were closely related to the content of MPC and the hardening process. The CSMPCs exhibited excellent bioactivity and good biocompatibility to support the cells to attach and proliferate on the surface. The CSMPC composite has the potential to serve as bone grafts for the bone regeneration. PMID:24411353

  13. Calcium-energized motor protein forisome controls damage in phloem: potential applications as biomimetic "smart" material.

    PubMed

    Srivastava, Vineet Kumar; Tuteja, Renu; Tuteja, Narendra

    2015-06-01

    Forisomes are ATP independent, mechanically active proteins from the Fabaceae family (also called Leguminosae). These proteins are located in sieve tubes of phloem and function to prevent loss of nutrient-rich photoassimilates, upon mechanical injury/wounding. Forisomes are SEO (sieve element occlusion) gene family proteins that have recently been shown to be involved in wound sealing mechanism. Recent findings suggest that forisomes could act as an ideal model to study self assembly mechanism for the development of nanotechnological devices like microinstruments, the microfluidic system frequently used in space exploration missions. Technology enabling improvement in micro instruments has been identified as a key technology by NASA in future space exploration missions. Forisomes are designated as biomimetic smart materials which are calcium-energized motor proteins. Since forisomes are biomolecules from plant systems it can be doctored through genetic engineering. In contrast, "smart" materials which are not derived from plants are difficult to modify in their properties. Current levels of understanding about forisomes conformational shifts with respect to calcium ions and pH changes requires supplement of future advances with relation to its 3D structure to understand self assembly processes. In plant systems it forms blood clots in the form of occlusions to prevent nutrient fluid leakage and thus proves to be a unique damage control system of phloem tissue. PMID:24020505

  14. Application of reference point indentation for micro-mechanical surface characterization of calcium silicate based dental materials.

    PubMed

    Antonijević, Djordje; Milovanović, Petar; Riedel, Christoph; Hahn, Michael; Amling, Michael; Busse, Björn; Djurić, Marija

    2016-04-01

    The objective of this study was to elucidate micromechanical properties of Biodentine and two experimental calcium silicate cements (CSCs) using Reference Point Indentation (RPI). Biomechanical characteristics of the cement type and the effects of a radiopacifier, liquid components, acid etching treatment and bioactivation in simulated body fluid (SBF) were investigated by measuring the microhardness, average unloading slope (Avg US) and indentation distance increase (IDI). Biodentine had a greater microhardness than the experimental CSCs, while the Avg US and IDI values were not significantly different among investigated materials. There was a statistically significant difference in microhardness and IDI values between pure CSCs and radiopacified cements (p < 0.05). Micromechanical properties were not affected by different liquid components used. Acid-etching treatment reduced Biodentine's microhardness while cements' immersion in SBF resulted in greater microhardness and higher IDI values compared to the control group. Clearly, the physiological environment and the cements' composition affect their surface micromechanical properties. The addition of calcium chloride and CSCs' immersion in SBF are beneficial for CSCs' micromechanical performance, while the addition of radiopacifiers and acid etching treatment weaken the CSCs' surface. Application of RPI aids with the characterization of micromechanical properties of synthetic materials' surfaces. PMID:26888441

  15. Porous microspheres of amorphous calcium phosphate: block copolymer templated microwave-assisted hydrothermal synthesis and application in drug delivery.

    PubMed

    Ding, Guan-Jun; Zhu, Ying-Jie; Qi, Chao; Lu, Bing-Qiang; Wu, Jin; Chen, Feng

    2015-04-01

    Amorphous calcium phosphate (ACP) microspheres with a porous and hollow structure have been prepared using an aqueous solution containing CaCl2 as a calcium source, adenosine triphosphate disodium salt (Na2ATP) as a phosphorus source in the presence of a block copolymer methoxyl poly(ethylene glycol)-block-poly(D,L-lactide) (mPEG-PLA) by the microwave-assisted hydrothermal method. The effects of microwave hydrothermal temperature and the concentrations of CaCl2 and Na2ATP on the crystal phase and morphology of the product are investigated. The as-prepared ACP porous hollow microspheres have a relatively high specific surface area of 232.9 m(2) g(-1) and an average pore size of 9.9 nm. A typical anticancer drug, docetaxel, is used to evaluate the drug loading ability and drug release behavior of ACP porous hollow microspheres in phosphate buffered saline (PBS) with different pH values of 4.5 and 7.4. The experiments reveal that the ACP porous hollow microspheres have a high drug loading capacity and favorable pH-responsive drug release property, and the ACP porous hollow microsphere drug delivery system shows a high ability to damage tumor cells. It is expected that the as-prepared ACP porous hollow microspheres are promising for the applications in various biomedical fields such as drug delivery. PMID:25535849

  16. Nanosized hydroxyapatite and other calcium phosphates: chemistry of formation and application as drug and gene delivery agents.

    PubMed

    Uskokovi?, Vuk; Uskokovi?, Dragan P

    2011-01-01

    The first part of this review looks at the fundamental properties of hydroxyapatite (HAP), the basic mineral constituent of mammalian hard tissues, including the physicochemical features that govern its formation by precipitation. A special emphasis is placed on the analysis of qualities of different methods of synthesis and of the phase transformations intrinsic to the formation of HAP following precipitation from aqueous solutions. This serves as an introduction to the second part and the main subject of this review, which relates to the discourse regarding the prospects of fabrication of ultrafine, nanosized particles based on calcium phosphate carriers with various therapeutic and/or diagnostic agents coated on and/or encapsulated within the particles. It is said that the particles could be either surface-functionalized with amphiphiles, peptides, proteins, or nucleic acids or injected with therapeutic agents, magnetic ions, or fluorescent molecules. Depending on the additive, they could be subsequently used for a variety of applications, including the controlled delivery and release of therapeutic agents (extracellularly or intracellularly), magnetic resonance imaging and hyperthermia therapy, cell separation, blood detoxification, peptide or oligonucleotide chromatography and ultrasensitive detection of biomolecules, and in vivo and in vitro gene transfection. Calcium phosphate nanoparticles as carriers of therapeutic agents that would enable a controlled drug release to treat a given bone infection and at the same be resorbed in the body so as to regenerate hard tissue lost to disease are emphasized hereby as one of the potentially attractive smart materials for the modern medicine. PMID:21061364

  17. Foliar ?15N is affected by foliar nitrogen uptake, soil nitrogen, and mycorrhizae along a nitrogen deposition gradient.

    PubMed

    Vallano, Dena M; Sparks, Jed P

    2013-05-01

    Foliar nitrogen isotope (?(15)N) composition patterns have been linked to soil N, mycorrhizal fractionation, and within-plant fractionations. However, few studies have examined the potential importance of the direct foliar uptake of gaseous reactive N on foliar ?(15)N. Using an experimental set-up in which the rate of mycorrhizal infection was reduced using a fungicide, we examined the influence of mycorrhizae on foliar ?(15)N in potted red maple (Acer rubrum) seedlings along a regional N deposition gradient in New York State. Mycorrhizal associations altered foliar ?(15)N values in red maple seedlings from 0.06 to 0.74 across sites. At the same sites, we explored the predictive roles of direct foliar N uptake, soil ?(15)N, and mycorrhizae on foliar ?(15)N in adult stands of A. rubrum, American beech (Fagus grandifolia), black birch (Betula lenta), and red oak (Quercus rubra). Multiple regression analysis indicated that ambient atmospheric nitrogen dioxide (NO2) concentration explained 0, 69, 23, and 45 % of the variation in foliar ?(15)N in American beech, red maple, red oak, and black birch, respectively, after accounting for the influence of soil ?(15)N. There was no correlation between foliar ?(13)C and foliar %N with increasing atmospheric NO2 concentration in most species. Our findings suggest that total canopy uptake, and likely direct foliar N uptake, of pollution-derived atmospheric N deposition may significantly impact foliar ?(15)N in several dominant species occurring in temperate forest ecosystems. PMID:23070141

  18. Hyperspectral remote sensing of foliar nitrogen content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A strong positive correlation between vegetation canopy Bidirectional Reflectance Factor (BRF) in the Near'InfraRed (NIR) spectral region and foliar mass-based nitrogen concentration (%N) has been reported in some temperate and boreal forests. This relationship, if true, would indicate an additional...

  19. Foliar Nitrogen Fertilization for Perennial Nursery Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen (N) availability affects plant growth and development and is intimately linked to the quality of nursery plants. In nursery production, N is commonly applied to the soil as controlled release and/or liquid fertilizers. However, research has shown that combining foliar N fertilization with a...

  20. Calcium - urine

    MedlinePLUS

    This test measures the amount of calcium in urine. All cells need calcium in order to work. ... A 24-hour urine sample is most often needed: On day 1, urinate into the toilet when you wake up in the morning. ...

  1. Calcium - ionized

    MedlinePLUS

    ... All cells need calcium in order to work. Calcium helps build strong bones and teeth. It is important for heart function. It also helps with muscle contraction, nerve signaling, and blood clotting. This article discusses ...

  2. Determination of foliar uptake of water droplets on waxy leaves in controlled environmental system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pertinent techniques for determination of plant cuticle permeability are needed to select proper doses of active ingredients and spray additives to improve pesticide application efficacy. A controlled environmental system with 100% relative humidity was developed for direct measurements of foliar up...

  3. Hyperspectral remote sensing of foliar nitrogen content.

    PubMed

    Knyazikhin, Yuri; Schull, Mitchell A; Stenberg, Pauline; Mttus, Matti; Rautiainen, Miina; Yang, Yan; Marshak, Alexander; Latorre Carmona, Pedro; Kaufmann, Robert K; Lewis, Philip; Disney, Mathias I; Vanderbilt, Vern; Davis, Anthony B; Baret, Frdric; Jacquemoud, Stphane; Lyapustin, Alexei; Myneni, Ranga B

    2013-01-15

    A strong positive correlation between vegetation canopy bidirectional reflectance factor (BRF) in the near infrared (NIR) spectral region and foliar mass-based nitrogen concentration (%N) has been reported in some temperate and boreal forests. This relationship, if true, would indicate an additional role for nitrogen in the climate system via its influence on surface albedo and may offer a simple approach for monitoring foliar nitrogen using satellite data. We report, however, that the previously reported correlation is an artifact--it is a consequence of variations in canopy structure, rather than of %N. The data underlying this relationship were collected at sites with varying proportions of foliar nitrogen-poor needleleaf and nitrogen-rich broadleaf species, whose canopy structure differs considerably. When the BRF data are corrected for canopy-structure effects, the residual reflectance variations are negatively related to %N at all wavelengths in the interval 423-855 nm. This suggests that the observed positive correlation between BRF and %N conveys no information about %N. We find that to infer leaf biochemical constituents, e.g., N content, from remotely sensed data, BRF spectra in the interval 710-790 nm provide critical information for correction of structural influences. Our analysis also suggests that surface characteristics of leaves impact remote sensing of its internal constituents. This further decreases the ability to remotely sense canopy foliar nitrogen. Finally, the analysis presented here is generic to the problem of remote sensing of leaf-tissue constituents and is therefore not a specific critique of articles espousing remote sensing of foliar %N. PMID:23213258

  4. Hyperspectral Remote Sensing of Foliar Nitrogen Content

    NASA Technical Reports Server (NTRS)

    Knyazikhin, Yuri; Schull, Mitchell A.; Stenberg, Pauline; Moettus, Matti; Rautiainen, Miina; Yang, Yan; Marshak, Alexander; Carmona, Pedro Latorre; Kaufmann, Robert K.; Lewis, Philip; Disney, Mathias I.; Vanderbilt, Vern; Davis, Anthony B.; Baret, Frederic; Jacquemoud, Stephane; Lyapustin, Alexei; Myneni, Ranga B.

    2013-01-01

    A strong positive correlation between vegetation canopy bidirectional reflectance factor (BRF) in the near infrared (NIR) spectral region and foliar mass-based nitrogen concentration (%N) has been reported in some temperate and boreal forests. This relationship, if true, would indicate an additional role for nitrogen in the climate system via its influence on surface albedo and may offer a simple approach for monitoring foliar nitrogen using satellite data. We report, however, that the previously reported correlation is an artifact - it is a consequence of variations in canopy structure, rather than of %N. The data underlying this relationship were collected at sites with varying proportions of foliar nitrogen-poor needleleaf and nitrogen-rich broadleaf species, whose canopy structure differs considerably. When the BRF data are corrected for canopy-structure effects, the residual reflectance variations are negatively related to %N at all wavelengths in the interval 423-855 nm. This suggests that the observed positive correlation between BRF and %N conveys no information about %N. We find that to infer leaf biochemical constituents, e.g., N content, from remotely sensed data, BRF spectra in the interval 710-790 nm provide critical information for correction of structural influences. Our analysis also suggests that surface characteristics of leaves impact remote sensing of its internal constituents. This further decreases the ability to remotely sense canopy foliar nitrogen. Finally, the analysis presented here is generic to the problem of remote sensing of leaf-tissue constituents and is therefore not a specific critique of articles espousing remote sensing of foliar %N.

  5. Active protein and calcium hydroxyapatite bilayers grown by laser techniques for therapeutic applications.

    PubMed

    Motoc, M M; Axente, E; Popescu, C; Sima, L E; Petrescu, S M; Mihailescu, I N; Gyorgy, E

    2013-09-01

    Active protein and bioceramic calcium hydroxyapatite (HA) bilayers were grown by combining conventional pulsed laser deposition (PLD) and matrix-assisted pulsed laser evaporation (MAPLE) techniques. A pulsed UV KrF* excimer laser was used for the irradiations. The HA layers were grown by PLD. Proteins with antimicrobial action were attached to the bioceramic layers using MAPLE. The composite MAPLE targets were obtained by dissolving the proteins powder in distilled water. The crystalline status and chemical composition of the obtained structures were studied by X-ray diffractometry and Fourier transform infrared spectroscopy. The layers were grown for the design of advanced future metal implants coatings, ensuring both enhanced bone formation and localized antimicrobial therapy. Our results demonstrated that protein coatings improve bone cell proliferation in vitro. Immunofluorescence experiments show that actin filaments stretch throughout bone cells and sustain their optimal spreading. PMID:23427118

  6. Size controlled hydroxyapatite and calcium carbonate particles: synthesis and their application as templates for SERS platform.

    PubMed

    Parakhonskiy, B V; Svenskaya, Yu I; Yashchenok, A ?; Fattah, H A; Inozemtseva, O A; Tessarolo, F; Antolini, R; Gorin, D A

    2014-06-01

    An elegant route for hydroxyapatite (HA) particle synthesis via ionic exchange reaction is reported. Calcium carbonate particles (CaCO3) were recrystallized into HA beads in water solution with phosphate ions. The size of initial CaCO3 particles was controlled upon the synthesis by varying the amount of ethylene glycol (EG) in aqueous solution. The average size of HA beads ranged from 0.60.1 to 4.31.1?m. Silver nanoparticles were deposited on the surface of HA and CaCO3 particles via silver mirror reaction. Surface enhanced Raman scattering of silver functionalized beads was demonstrated by detecting Rhodamine B. CaCO3 and HA particles have a great potential for design of carrier which can provide diagnostic and therapeutic functions. PMID:24802965

  7. Osteogenic biphasic calcium sulphate dihydrate/iron-modified alpha-tricalcium phosphate bone cement for spinal applications: in vivo study.

    PubMed

    Vlad, M D; Sindilar, E V; Marioso, M L; Poeat?, I; Torres, R; Lpez, J; Barrac, M; Fernndez, E

    2010-02-01

    In this study, the biocompatibility and the osteogenic features of a new iron-modified alpha-tricalcium phosphate (IM/alpha-TCP) and calcium sulphate dihydrate (CSD) biphasic cement (IM/alpha-TCP/CSD-BC) have been investigated in terms of the in vivo cement resorption, bone tissue formation and host tissue response on sheep animal model. Histological evaluation performed on undecalcified cement-bone specimens assessed the in vivo behaviour. It has been shown that the new IM/alpha-TCP/CSD-BC has the ability to produce firm bone binding in vivo (i.e. bioactivity). Qualitative histology proved cement biocompatibility, osteoconduction and favourable resorption, mainly through a macrophage-mediated mechanism. The results showed that the new cements have biocompatible and osteogenic features of interest as possible cancellous bone replacement biomaterial for minimally invasive spinal surgery applications. PMID:19607944

  8. Effect of curing conditions on the dimensional and thermal stability of calcium phosphate cement for elevated temperature applications

    SciTech Connect

    Blom, Johan; Rahier, Hubert; Wastiels, Jan

    2014-12-15

    Calcium phosphate cements (CPCs) are attractive materials for elevated temperature applications, like moulds to process thermoplastics up to 300 °C. The CPC resulting from the reaction of wollastonite with phosphoric acid cured at room temperature however contains hydrated phases like brushite, and is thus not stable when exposed to temperatures above 200 °C. A non-contact method based on digital image correlation demonstrated that isothermal curing at 60 °C reduces the thermal shrinkage up to 300 °C by 25%. This curing method results in the direct formation of the more stable monetite in a shorter curing time. The correlated results of TGA, pH of the filtration water, and DSC analysis on partially cured material indicate this. XRD diffractograms and SEM images in combination with EDX show the evolution of the transformation of wollastonite into monetite, and the structure and morphology of the formed material.

  9. PARTITIONING THE RELATIVE INFLUENCE OF SOIL N, MYCORRHIZAE, AND FOLIAR N UPTAKE ON FOLIAR ?15N PATTERNS: CAN WE DETECT FOLIAR UPTAKE OF REACTIVE N?

    NASA Astrophysics Data System (ADS)

    Vallano, D.; Sparks, J. P.

    2009-12-01

    Vegetation is an important sink for atmospheric reactive N in N-limited systems and may be capable of incorporating reactive N compounds directly into leaves through the foliar uptake pathway. A proxy for atmospheric reactive N entering vegetation would be useful to estimate the impact of direct foliar N uptake on plant metabolism. Natural abundance foliar N isotopic composition (?15N) is a practical tool for this purpose because plant-available N sources often have different isotopic compositions. Current understanding of foliar ?15N suggests these values primarily represent the integration of soil ?15N, direct foliar N uptake, mycorrhizal fractionation, and within-plant fractionations. Using a potted plant mesocosm system, we estimated the influence of mycorrhizae on foliar ?15N patterns in red maple (Acer rubrum) seedlings along an N deposition gradient in New York State. We found that mycorrhizal associations altered foliar ?15N in red maple seedlings from 0.03 - 1.01 across sites. Along the same temporal and spatial scales, we examined the influence of soil ?15N, foliar N uptake, and mycorrhizae on foliar ?15N in adult stands of American beech (Fagus grandifolia), black birch (Betula lenta), red maple (A. rubrum), and red oak (Quercus rubra). Using multiple regression models, atmospheric NO2 concentration explained 0%, 69%, 23%, and 45% of the residual variation in foliar ?15N remaining in American beech, red maple, red oak, and black birch, respectively, after accounting for soil ?15N. Our results suggest that foliar ?15N may be used to estimate pollution-derived atmospheric reactive N entering vegetation via the foliar N uptake pathway.

  10. Calcium Channels

    NASA Astrophysics Data System (ADS)

    Corry, Ben; Hool, Livia

    Ion channels underlie the electrical activity of cells. Calcium channels have a unique functional role, because not only do they participate in this activity, they form the means bywhich electrical signals are converted to responses within the cell. Calcium concentrations in the cytoplasm of cells are maintained at a low level, and calcium channels activate quickly such that the opening of ion channels can rapidly change the cytoplasmic environment. Once inside the cell, calcium acts as a "second messenger" prompting responses by binding to a variety of calcium sensitive proteins. Calcium channels are known to play an important role in stimulating muscle contraction, in neurotransmitter secretion, gene regulation, activating other ion channels, controlling the shape and duration of action potentials and many other processes. Since calcium plays an integral role in cell function, and since excessive quantities can be toxic, its movement is tightly regulated and controlled through a large variety of mechanisms.

  11. A microwave-assisted solution combustion synthesis to produce europium-doped calcium phosphate nanowhiskers for bioimaging applications.

    PubMed

    Wagner, Darcy E; Eisenmann, Kathryn M; Nestor-Kalinoski, Andrea L; Bhaduri, Sarit B

    2013-09-01

    Biocompatible nanoparticles possessing fluorescent properties offer attractive possibilities for multifunctional bioimaging and/or drug and gene delivery applications. Many of the limitations with current imaging systems center on the properties of the optical probes in relation to equipment technical capabilities. Here we introduce a novel high aspect ratio and highly crystalline europium-doped calcium phosphate nanowhisker produced using a simple microwave-assisted solution combustion synthesis method for use as a multifunctional bioimaging probe. X-ray diffraction confirmed the material phase as europium-doped hydroxyapatite. Fluorescence emission and excitation spectra and their corresponding peaks were identified using spectrofluorimetry and validated with fluorescence, confocal and multiphoton microscopy. The nanowhiskers were found to exhibit red and far red wavelength fluorescence under ultraviolet excitation with an optimal peak emission of 696 nm achieved with a 350 nm excitation. Relatively narrow emission bands were observed, which may permit their use in multicolor imaging applications. Confocal and multiphoton microscopy confirmed that the nanoparticles provide sufficient intensity to be utilized in imaging applications. PMID:23764803

  12. Entrapment of iron nanoparticles in calcium alginate beads for groundwater remediation applications.

    PubMed

    Bezbaruah, Achintya N; Krajangpan, Sita; Chisholm, Bret J; Khan, Eakalak; Bermudez, Juan J Elorza

    2009-07-30

    Zero-valent iron nanoparticles (nZVI) have been successfully entrapped in biopolymer, calcium (Ca)-alginate beads. The study has demonstrated the potential use of this technique in environmental remediation using nitrate as a model contaminant. Ca-alginate beads show promise as an entrapment medium for nZVI for possible use in groundwater remediation. Based on scanning electron microscopy images it can be inferred that the alginate gel cluster acts as a bridge that binds the nZVI particles together. Kinetic experiments with 100, 60, and 20mg NO(3)(-)-NL(-1) indicate that 50-73% nitrate-N removal was achieved with entrapped nZVI as compared to 55-73% with bare nZVI over a 2-h period. The controls ran simultaneously show little NO(3)(-)-N removal. Statistical analysis indicates that there was no significant difference between the reaction rates of bare and entrapped nZVI. The authors have shown for the first time that nZVI can be effectively entrapped in Ca-alginate beads and no significant decrease in the reactivity of nZVI toward the model contaminant (nitrate here) was observed after the entrapment. PMID:19178997

  13. Electrodeposition of porous hydroxyapatite/calcium silicate composite coating on titanium for biomedical applications

    NASA Astrophysics Data System (ADS)

    Huang, Yong; Han, Shuguang; Pang, Xiaofeng; Ding, Qionqion; Yan, Yajing

    2013-04-01

    A novel method of electrolytic porous hydroxyapatite/calcium silicate (HA/CaSiO3) composite coating was conducted on pure titanium in a mixed solution of nano-SiO2, Ca(NO3)2 and NH4H2PO4. SEM observation showed that the composite layer was porous, thereby providing abundant sites for the osteoblast adhesion. XRD results showed that the composite coating was mainly composed of HA and CaSiO3. Bond strength testing exhibited that HA-CaSiO3/Ti had higher bond strength than HA/Ti. The HA/CaSiO3 coating was more corrosion resistant than the HA coating based on the polarization tests. In vitro cell experiments demonstrated that both the HA and HA/CaSiO3 coatings showed better cell response than the bared titanium. In addition, the proliferation of MC3T3-E1 osteoblast cells grown on the HA/CaSiO3 coating were remarkably higher than those on the bared Ti and pure HA coating.

  14. Corn silage from corn treated with foliar fungicide and performance of Holstein cows.

    PubMed

    Haerr, K J; Lopes, N M; Pereira, M N; Fellows, G M; Cardoso, F C

    2015-12-01

    Foliar fungicide application to corn plants is used in corn aimed for corn silage in the dairy industry, but questions regarding frequency of application and its effect on corn silage quality and feed conversion when fed to dairy cows remain prevalent. The objective of this study was to evaluate the effects of various foliar fungicide applications to corn on dry matter intake (DMI), milk production, and milk composition when fed to dairy cows. Sixty-four Holstein cows with parity 2.51.5, 65380kg of body weight, and 16151d in milk were blocked and randomly assigned to 1 of 4 corn silage treatments (total mixed ration with 35% of the dry matter as corn silage). Treatments were as follows: control (CON), corn silage with no applications of foliar fungicide; treatment 1 (1X), corn silage from corn that received 1 application of pyraclostrobin (PYR) foliar fungicide (Headline; BASF Corp.) at corn vegetative stage 5; treatment 2 (2X), corn silage from corn that received the same application as 1X plus another application of a mixture of PYR and metconazole (Headline AMP; BASF Corp.) at corn reproductive stage 1 ("silking"); and treatment 3 (3X), corn silage from corn that received the same applications as 2X as well as a third application of PYR and metconazole at reproductive stage 3 ("milky kernel"). Corn was harvested at about 32% dry matter and 3/4 milk line stage of kernel development and ensiled for 200d. Treatments were fed to cows for 5wk, with the last week being used for statistical inferences. Week -1 was used as a covariate in the statistical analysis. Dry matter intake tended to be lower for cows fed corn silage treated with fungicide than CON (23.8, 23.0, 19.5, and 21.3kg for CON, 1X, 2X, and 3X, respectively). A linear treatment effect for DMI was observed, with DMI decreasing as foliar fungicide applications increased. Treatments CON, 1X, 2X, and 3X did not differ for milk yield (34.5, 34.5, 34.2, and 34.4kg/d, respectively); however, a trend for increased feed conversion represented by fat-corrected milk/DMI (1.65 vs. 1.47) and energy-corrected milk/DMI (1.60 vs. 1.43) was noted for cows fed corn silage with fungicide compared with CON. In conclusion, cows receiving corn silage treated with foliar fungicide had better conversion of feed dry matter to milk than those receiving CON silage. PMID:26476949

  15. Assessment of Pain Intensity in Patients with Dentin Hypersensitivity After Application of Prophylaxis Paste Based on Calcium Sodium Phosphosilicate Formula

    PubMed Central

    Cha?as, Renata; Wjcik-Ch?ci?ska, Ilona; Zamo?ci?ska, Jolanta; Bachanek, Teresa

    2015-01-01

    Background One of many functions of the pulp-dentin complex is sensory function. Acute, situated, receding pain after the cessation of the stimulus action is called dentin pain. Dentin hypersensitivity has been described as one of the most painful and least successfully treated chronic ailments of teeth. The aim of this research was the clinical evaluation of the effectiveness of professional polishing paste containing calcium sodium phosphosilicate formula (NovaMin) in eliminating dentin hypersensitivity after a single application. Material/Methods The study comprised 92 teeth with dentin hypersensitivity diagnosed on the basis of history and clinical examination. The pain reaction of exposed dentine was induced by tactile and dehydrating stimuli, asking patients to assess the severity of pain on the VAS scale. Clinical trial and survey were carried out twice: before and 1 week after the application of the polishing paste. Results After the application of the examined paste, the percentage of teeth reacting with a severe pain to the touch of the probe decreased from 16.3% to 4.3%, and with a moderate pain from 42.4% to 12%. Examination after applying dehydrating stimulus a week after carrying out the application showed a decrease in the proportion of teeth with strong pain from 28.3% to 0% and moderate pain from 38% to 15.2%. The lack of pain increased from 12% to about 50%. Conclusions The use of prophylactic professional paste with NovaMin formula in in-office procedure provides the reduction of dentin hypersensitivity noticeable by 1 week after application. PMID:26429677

  16. Current perspectives of bio-ceramic technology in endodontics: calcium enriched mixture cement - review of its composition, properties and applications

    PubMed Central

    Nawal, Ruchika Roongta; Talwar, Sangeeta; Verma, Mahesh

    2015-01-01

    Advancements in bio-ceramic technology has revolutionised endodontic material science by enhancing the treatment outcome for patients. This class of dental materials conciliates excellent biocompatibility with high osseoconductivity that render them ideal for endodontic care. Few recently introduced bio-ceramic materials have shown considerable clinical success over their early generations in terms of good handling characteristics. Calcium enriched mixture (CEM) cement, Endosequence sealer, and root repair materials, Biodentine and BioAggregate are the new classes of bio-ceramic materials. The aim of this literature review is to present investigations regarding properties and applications of CEM cement in endodontics. A review of the existing literature was performed by using electronic and hand searching methods for CEM cement from January 2006 to December 2013. CEM cement has a different chemical composition from that of mineral trioxide aggregate (MTA) but has similar clinical applications. It combines the biocompatibility of MTA with more efficient characteristics, such as significantly shorter setting time, good handling characteristics, no staining of tooth and effective seal against bacterial leakage. PMID:25671207

  17. Current perspectives of bio-ceramic technology in endodontics: calcium enriched mixture cement - review of its composition, properties and applications.

    PubMed

    Utneja, Shivani; Nawal, Ruchika Roongta; Talwar, Sangeeta; Verma, Mahesh

    2015-02-01

    Advancements in bio-ceramic technology has revolutionised endodontic material science by enhancing the treatment outcome for patients. This class of dental materials conciliates excellent biocompatibility with high osseoconductivity that render them ideal for endodontic care. Few recently introduced bio-ceramic materials have shown considerable clinical success over their early generations in terms of good handling characteristics. Calcium enriched mixture (CEM) cement, Endosequence sealer, and root repair materials, Biodentine and BioAggregate are the new classes of bio-ceramic materials. The aim of this literature review is to present investigations regarding properties and applications of CEM cement in endodontics. A review of the existing literature was performed by using electronic and hand searching methods for CEM cement from January 2006 to December 2013. CEM cement has a different chemical composition from that of mineral trioxide aggregate (MTA) but has similar clinical applications. It combines the biocompatibility of MTA with more efficient characteristics, such as significantly shorter setting time, good handling characteristics, no staining of tooth and effective seal against bacterial leakage. PMID:25671207

  18. Alleviation of cadmium toxicity in Brassica juncea L. (Czern. & Coss.) by calcium application involves various physiological and biochemical strategies.

    PubMed

    Ahmad, Parvaiz; Sarwat, Maryam; Bhat, Nazir Ahmad; Wani, Mohd Rafiq; Kazi, Alvina Gul; Tran, Lam-Son Phan

    2015-01-01

    Calcium (Ca) plays important role in plant development and response to various environmental stresses. However, its involvement in mitigation of heavy metal stress in plants remains elusive. In this study, we examined the effect of Ca (50 mM) in controlling cadmium (Cd) uptake in mustard (Brassica juncea L.) plants exposed to toxic levels of Cd (200 mg L(-1) and 300 mg L(-1)). The Cd treatment showed substantial decrease in plant height, root length, dry weight, pigments and protein content. Application of Ca improved the growth and biomass yield of the Cd-stressed mustard seedlings. More importantly, the oil content of mustard seeds of Cd-stressed plants was also enhanced with Ca treatment. Proline was significantly increased in mustard plants under Cd stress, and exogenously sprayed Ca was found to have a positive impact on proline content in Cd-stressed plants. Different concentrations of Cd increased lipid peroxidation but the application of Ca minimized it to appreciable level in Cd-treated plants. Excessive Cd treatment enhanced the activities of antioxidant enzymes superoxide dismutase, ascorbate peroxidase and glutathione reductase, which were further enhanced by the addition of Ca. Additionally, Cd stress caused reduced uptake of essential elements and increased Cd accumulation in roots and shoots. However, application of Ca enhanced the concentration of essential elements and decreased Cd accumulation in Cd-stressed plants. Our results indicated that application of Ca enables mustard plant to withstand the deleterious effect of Cd, resulting in improved growth and seed quality of mustard plants. PMID:25629695

  19. Alleviation of Cadmium Toxicity in Brassica juncea L. (Czern. & Coss.) by Calcium Application Involves Various Physiological and Biochemical Strategies

    PubMed Central

    Ahmad, Parvaiz; Sarwat, Maryam; Bhat, Nazir Ahmad; Wani, Mohd Rafiq; Kazi, Alvina Gul; Tran, Lam-Son Phan

    2015-01-01

    Calcium (Ca) plays important role in plant development and response to various environmental stresses. However, its involvement in mitigation of heavy metal stress in plants remains elusive. In this study, we examined the effect of Ca (50 mM) in controlling cadmium (Cd) uptake in mustard (Brassica juncea L.) plants exposed to toxic levels of Cd (200 mg L−1 and 300 mg L−1). The Cd treatment showed substantial decrease in plant height, root length, dry weight, pigments and protein content. Application of Ca improved the growth and biomass yield of the Cd-stressed mustard seedlings. More importantly, the oil content of mustard seeds of Cd-stressed plants was also enhanced with Ca treatment. Proline was significantly increased in mustard plants under Cd stress, and exogenously sprayed Ca was found to have a positive impact on proline content in Cd-stressed plants. Different concentrations of Cd increased lipid peroxidation but the application of Ca minimized it to appreciable level in Cd-treated plants. Excessive Cd treatment enhanced the activities of antioxidant enzymes superoxide dismutase, ascorbate peroxidase and glutathione reductase, which were further enhanced by the addition of Ca. Additionally, Cd stress caused reduced uptake of essential elements and increased Cd accumulation in roots and shoots. However, application of Ca enhanced the concentration of essential elements and decreased Cd accumulation in Cd-stressed plants. Our results indicated that application of Ca enables mustard plant to withstand the deleterious effect of Cd, resulting in improved growth and seed quality of mustard plants. PMID:25629695

  20. Phosphorous acid residues in apples after foliar fertilization: results of field trials.

    PubMed

    Malusà, E; Tosi, L

    2005-06-01

    The levels of phosphorous acid residues in apples after foliar fertilization with P fertilizers and after treatment with a phosphonate fungicide (Fosetyl-Al) were determined and compared. Two field trials and a glasshouse experiment, using different genotypes and plants of different age, were carried out and monitored over a three-year period. Phosphorous acid residues were found in apples after application of foliar P fertilizers. Concentrations of the residues ranged between 0.02 and 14 mg kg(-1) depending on the phosphorous acid content in the fertilizer used and the plant size and yield. The treatments induced an accumulation of the residue in the course of the experiments, which in some cases reached a level exceeding the maximum limit set by EU legislation. Residues were also detected in other plant organs, i.e., roots and buds. Plants treated with Fosetyl-Al contained phosphorous acid residues in their fruits and buds two years after the suspension of the treatment, suggesting a long-term persistence of the substance in plant storage organs. A second experiment, involving treatment of trees with seven foliar fertilizers of different composition, also induced accumulation of phosphorous acid residues in fruits. It is concluded that a wide array of foliar products containing phosphorous acid, even as a minor component, could mimic the residue effect of phosphonate fungicide treatments. PMID:16019827

  1. Biphasic calcium sulfate dihydrate/iron-modified alpha-tricalcium phosphate bone cement for spinal applications: in vitro study.

    PubMed

    Vlad, M D; Valle, L J; Poeat?, I; Lpez, J; Torres, R; Barrac, M; Fernndez, E

    2010-04-01

    In this study, the cytocompatibility of new 'iron-modified/alpha-tricalcium phosphate (IM/alpha-TCP) and calcium sulfate dihydrate (CSD)' bone cement (IM/alpha-TCP/CSD-BC) intended for spinal applications has been approached. The objective was to investigate by direct-contact osteoblast-like cell cultures (from 1 to 14 days) the in vitro cell adhesion, proliferation, morphology and cytoskeleton organization of MG-63 cells seeded onto the new cements. The results were as follows: (a) quantitative MTT-assay and scanning electron microscopy (SEM) showed that cell adhesion, proliferation and viability were not affected with time by the presence of iron in the cements; (b) double immunofluorescent labeling of F-actin and alpha-tubulin showed a dynamic interaction between the cell and its porous substrates sustaining the locomotion phenomenon on the cements' surface, which favored the colonization, and confirming the biocompatibility of the experimental cements; (c) SEM-cell morphology and cytoskeleton observations also evidenced that MG-63 cells were able to adhere, to spread and to attain normal morphology on the new IM/alpha-TCP/CSD-BC which offered favorable substratum properties for osteoblast-like cells proliferation and differentiation in vitro. The results showed that these new iron-modified cement-like biomaterials have cytocompatible features of interest not only as possible spinal cancellous bone replacement biomaterial but also as bone tissue engineering scaffolds. PMID:20308776

  2. Microstructure, corrosion properties and bio-compatibility of calcium zinc phosphate coating on pure iron for biomedical application.

    PubMed

    Chen, Haiyan; Zhang, Erlin; Yang, Ke

    2014-01-01

    In order to improve the biocompatibility and the corrosion resistance in the initial stage of implantation, a phosphate (CaZn2(PO4)22H2O) coating was obtained on the surface of pure iron by a chemical reaction method. The anti-corrosion property, the blood compatibility and the cell toxicity of the coated pure iron specimens were investigated. The coating was composed of some fine phosphate crystals and the surface of coating was flat and dense enough. The electrochemical data indicated that the corrosion resistance of the coated pure iron was improved with the increase of phosphating time. When the specimen was phosphated for 30min, the corrosion resistance (Rp) increased to 8006 ?. Compared with that of the naked pure iron, the anti-hemolysis property and cell compatibility of the coated specimen was improved significantly, while the anti-coagulant property became slightly worse due to the existence of element calcium. It was thought that phosphating treatment might be an effective method to improve the biocompatibility of pure iron for biomedical application. PMID:24268250

  3. Application of calcium carbonate slows down organic amendments mineralization in reclaimed soils

    NASA Astrophysics Data System (ADS)

    Zornoza, Ral; Faz, ngel; Acosta, Jos A.; Martnez-Martnez, Silvia; ngeles Muoz, M.

    2014-05-01

    A field experiment was set up in Cartagena-La Unin Mining District, SE Spain, aimed at evaluating the short-term effects of pig slurry (PS) amendment alone and together with marble waste (MW) on organic matter mineralization, microbial activity and stabilization of heavy metals in two tailing ponds. These structures pose environmental risk owing to high metals contents, low organic matter and nutrients, and null vegetation. Carbon mineralization, exchangeable metals and microbiological properties were monitored during 67 days. The application of amendments led to a rapid decrease of exchangeable metals concentrations, except for Cu, with decreases up to 98%, 75% and 97% for Cd, Pb and Zn, respectively. The combined addition of MW+PS was the treatment with greater reduction in metals concentrations. The addition of PS caused a significant increase in respiration rates, although in MW+PS plots respiration was lower than in PS plots. The mineralised C from the pig slurry was low, approximately 25-30% and 4-12% for PS and MW+PS treatments, respectively. Soluble carbon (Csol), microbial biomass carbon (MBC) and ?-galactosidase and ?-glucosidase activities increased after the application of the organic amendment. However, after 3 days these parameters started a decreasing trend reaching similar values than control from approximately day 25 for Csol and MBC. The PS treatment promoted highest values in enzyme activities, which remained high upon time. Arylesterase activity increased in the MW+PS treatment. Thus, the remediation techniques used improved soil microbiological status and reduced metal availability. The combined application of PS+MW reduced the degradability of the organic compounds. Keywords: organic wastes, mine soils stabilization, carbon mineralization, microbial activity.

  4. Foliar phloem infrastructure in support of photosynthesis

    PubMed Central

    Adams, William W.; Cohu, Christopher M.; Muller, Onno; Demmig-Adams, Barbara

    2013-01-01

    Acclimatory adjustments of foliar minor loading veins in response to growth at different temperatures and light intensities are evaluated. These adjustments are related to their role in providing infrastructure for the export of photosynthetic products as a prerequisite for full acclimation of photosynthesis to the respective environmental conditions. Among winter-active apoplastic loaders, higher photosynthesis rates were associated with greater numbers of sieve elements per minor vein as well as an increased apparent total membrane area of cells involved in phloem loading (greater numbers of cells and/or greater cell wall invaginations). Among summer-active apoplastic loaders, higher photosynthesis rates were associated with increased vein density and, possibly, a greater number of sieve elements and companion cells per minor vein. Among symplastic loaders, minor loading vein architecture (number per vein and arrangement of cells) was apparently constrained, but higher photosynthesis rates were associated with higher foliar vein densities and larger intermediary cells (presumably providing a greater volume for enzymes involved in active raffinose sugar synthesis). Winter-active apoplastic loaders thus apparently place emphasis on adjustments of cell membrane area (presumably available for transport proteins active in loading of minor veins), while symplastic loaders apparently place emphasis on increasing the volume of cells in which their active loading step takes place. Presumably to accommodate a greater flux of photosynthate through the foliar veins, winter-active apoplastic loaders also have a higher number of sieve elements per minor loading vein, whereas symplastic loaders and summer-active apoplastic loaders have a higher total number of veins per leaf area. These latter adjustments in the vasculature (during leaf development) may also apply to the xylem (via greater numbers of tracheids per vein and/or greater vein density per leaf area) serving to increase water flux to mesophyll tissues in support of high rates of transpiration typically associated with high rates of photosynthesis. PMID:23785375

  5. Micro-arc oxidation as a tool to develop multifunctional calcium-rich surfaces for dental implant applications.

    PubMed

    Ribeiro, A R; Oliveira, F; Boldrini, L C; Leite, P E; Falagan-Lotsch, P; Linhares, A B R; Zambuzzi, W F; Fragneaud, B; Campos, A P C; Gouva, C P; Archanjo, B S; Achete, C A; Marcantonio, E; Rocha, L A; Granjeiro, J M

    2015-09-01

    Titanium (Ti) is commonly used in dental implant applications. Surface modification strategies are being followed in last years in order to build Ti oxide-based surfaces that can fulfill, simultaneously, the following requirements: induced cell attachment and adhesion, while providing a superior corrosion and tribocorrosion performance. In this work micro-arc oxidation (MAO) was used as a tool for the growth of a nanostructured bioactive titanium oxide layer aimed to enhance cell attachment and adhesion for dental implant applications. Characterization of the surfaces was performed, in terms of morphology, topography, chemical composition and crystalline structure. Primary human osteoblast adhesion on the developed surfaces was investigated in detail by electronic and atomic force microscopy as well as immunocytochemistry. Also an investigation on the early cytokine production was performed. Results show that a relatively thick hybrid and graded oxide layer was produced on the Ti surface, being constituted by a mixture of anatase, rutile and amorphous phases where calcium (Ca) and phosphorous (P) were incorporated. An outermost nanometric-thick amorphous oxide layer rich in Ca was present in the film. This amorphous layer, rich in Ca, improved fibroblast viability and metabolic activity as well as osteoblast adhesion. High-resolution techniques allowed to understand that osteoblasts adhered less in the crystalline-rich regions while they preferentially adhere and spread over in the Ca-rich amorphous oxide layer. Also, these surfaces induce higher amounts of IFN-? cytokine secretion, which is known to regulate inflammatory responses, bone microarchitecture as well as cytoskeleton reorganization and cellular spreading. These surfaces are promising in the context of dental implants, since they might lead to faster osseointegration. PMID:26046283

  6. Calcium Film Based Testing of Edge-Seal Materials for Photovoltaic Applications (Presentation)

    SciTech Connect

    Kempe, M.; Dameron, A.; Reese, M.

    2011-04-01

    Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, dessicant-filled polyisobutene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.

  7. Estimation of Canopy Foliar Biomass with Spectral Reflectance Measurements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canopy foliar biomass, defined as the product of leaf dry matter content and leaf area index, is an important measurement for global biogeochemical cycles. This study explores the potential for retrieving foliar biomass in green canopies using a spectral index, the Normalized Dry Matter Index (NDMI)...

  8. FOLIAR WASHOFF OF PESTICIDES (FWOP) MODEL: DEVELOPMENT AND EVALUATION

    EPA Science Inventory

    The Foliar Washoff of Pesticides (FWOP) Model was developed to provide an empirical simulation of pesticide washoff from plant leaf surfaces as influenced by rainfall amount. To evaluate the technique, simulations by the FWOP Model were compared to those by the foliar washoff alg...

  9. Flux growth of yttrium calcium oxy borate (YCOB) single crystals for nonlinear optical applications

    NASA Astrophysics Data System (ADS)

    Arun Kumar, R.; Dhanasekaran, R.

    2009-01-01

    Nonlinear optical single crystals of YCa 4O(BO 3) 3 (YCOB) with good optical quality were grown from boron-tri-oxide flux for the first time. Polycrystalline YCOB samples were synthesized from the solid-state reaction method. Optimum conditions for the growth of YCOB crystals from the flux were determined. Single crystals of YCOB with dimensions 1055 mm 3 were obtained by the method of 'slow cooling'. The grown crystals were characterized by XRD, UV-vis-NIR, and Fourier transform infrared (FTIR) studies. The powder XRD pattern reveals the formation of YCOB compound. The lattice parameters were identified through single crystal XRD studies. The UV-vis-NIR results show that the crystal has a sharp cutoff at 220 nm and is nearly 78% transparent over a wide wavelength range enabling it for applications in the UV region. The functional groups belonging to the YCOB single crystals were identified by the FTIR results. The primary emphasis is laid to describe 'flux technique' as an alternative method to grow YCOB single crystals. The results are presented and discussed.

  10. Foliar Expression of Parent Lithologic Composition in the Sub-Arctic: Examples from Heath Ecosystems of Abisko, Sweden.

    NASA Astrophysics Data System (ADS)

    Heim, E. W.; Tomczyk, N.; Remiszewski, K.; Bryce, J. G.; Frey, S. D.; Prado, M. F.; Varner, R. K.

    2014-12-01

    Climatic evolution and its effect on ecosystem stability through macronutrient acquisition is of particular interest in the fringe ecosystems of the Arctic and Sub-Arctic, regions predicted to face the most extreme temperature increases in Earth's changing climate. Accordingly enhanced understanding of climate change impacts on nutrient mobilization in recently glaciated terrains will factor importantly into accurate predictive models for future ecosystem health. Lithologic variation can lead to differences in geomorphic processes and thus influence landscape evolution [1]. Heath ecosystems in the region are developed on thin soils which place them close to parent material bedrock. Given the abundance of thin soils mantling bedrock, we assessed how bedrock geochemical content links with foliar composition of key macronutrients. We focused our studies on four sites near Abisko, Sweden (6821'N 1902'E) in metamorphosed sedimentary bedrock. In our sites the average annual air temperature has crossed the 0o threshold and has been linked to many cryospheric and ecological impacts [2]. Sites were chosen at the same elevation (700 m absl) and shared similar vegetation coverage. Three dominant species across our sampling sites include Betula nana, Empetrum nigrum, and Salix lapponum. E. Nigrum had consistent concentrations of foliar magnesium (Mg) and phosphorus (P) across the bedrock compositional gradients. B. nana and S. lapponum had consistently higher foliar Mg and P concentrations than E. nigrum across the gradients. Across a soil calcium (Ca) gradient, dominant species had a weak correlation between soil Ca and foliar Ca contents, R2 = 0.106. Soil Mg and P gradients were similarly poorly correlated with foliar abundances, R2 = -0.0228, and R2= -0.034 respectively. Expansion of our work into other lithologies will contribute towards improved predictive biogeochemical models of macronutrient acquisition and ecological evolution across changing Arctic ecosystems.

  11. Phytotoxicity of foliar-applied urea.

    PubMed

    Krogmeier, M J; McCarty, G W; Bremner, J M

    1989-11-01

    Recent work in our laboratory showed that the adverse effect of urea fertilizer on seed germination and seedling growth in soil is due to ammonia produced through hydrolysis of urea by soil urease (NH(2)CONH(2) + H(2)O --> 2NH(3) + CO(2)) and can be eliminated by amending the fertilizer with a small amount of a urease inhibitor such as phenylphosphorodiamidate. Because the leaf-tip necrosis often observed after foliar fertilization of plants with urea is usually attributed to ammonia formed through hydrolysis of urea by plant urease, we studied the possibility that this necrosis could be eliminated or reduced by adding phenylphosphorodiamidate to the urea fertilizer. We found that, although addition of this urease inhibitor to foliar-applied urea increased the urea content and decreased the ammonia content and urease activity of soybean [Glycine max. (L.) Merr.] leaves fertilized with urea, it increased the leaf-tip necrosis observed after fertilization. We conclude that this necrosis resulted from accumulation of toxic amounts of urea rather than from formation of toxic amounts of ammonia. This conclusion was supported by our finding that the necrotic areas of soybean leaves treated with urea or with urea and phenylphosphorodiamidate contained much higher concentrations of urea than did the nonnecrotic areas. PMID:16594077

  12. Assessment of gadolinium calcium oxoborate (GdCOB) for laser applications

    NASA Astrophysics Data System (ADS)

    Bajor, A. L.; Kisielewski, J.; Kłos, A.; Kopczyński, K.; Łukasiewicz, T.; Mierczyk, J.; Młyńczak, J.

    2011-12-01

    Increasing demand for growing high quality laser crystals puts a question about their most important parameters that one should concentrate on to get a desired product which will exhibit best properties in practical use. And by no means, this is a simple question. Apart of the usual lasing properties associated with a special dopant in the host material itself, one needs to consider another two lasing phenomena, namely second (SHG) and higher harmonic generation, and self-frequency doubling (SFD). Not necessarily all of these three can meet altogether in the same host material to yield in its best appearance in every case. We have made a review of basic properties of gadolinium oxoborate GdCa4O(BO3)3 (GdCOB) crystal and came to the conclusion that, currently, as a host material this is probably the best in all of its lasing applications. Although GdCOB has low thermal conductivity, which requires a suitable cooling, on the other hand it has got small thermo-optic coefficients which govern good operation in SHG and SFD experiments. Two inch dia. Nd-doped crystals were grown by the Czochralski technique. Since a large discrepancy in the literature exists on exact values of nonlinear coefficients, one is never sure about this whether theoretically predicted phase-matching angles (PMA) are those that are really optimal. Besides, none has yet measured the values of nonlinear coefficients as a function of doping concentration. Therefore we have not decided to cut numerous differently oriented samples for generation of different wavelengths in SHG and SFD, but rather tried to generate different wavelengths from the same samples. We have also not paid special attention to get highest possible conversion efficiencies. However, we have concentrated our attention on potential use of the core region in laser technique. Unlike in YAG crystals, when the core is by all means a parasitic structure, we discovered that the core region in GdCOB, that majority of investigators are even not aware of its presence in the crystal, can be also useful in laser technique. According to our best knowledge, a SHG of red light in this work is the second reported case in the world-wide literature.

  13. Calcium orthophosphates

    PubMed Central

    Dorozhkin, Sergey V.

    2011-01-01

    The present overview is intended to point the readers’ attention to the important subject of calcium orthophosphates. This type of materials is of special significance for human beings, because they represent the inorganic part of major normal (bones, teeth and antlers) and pathological (i.e., those appearing due to various diseases) calcified tissues of mammals. For example, atherosclerosis results in blood vessel blockage caused by a solid composite of cholesterol with calcium orthophosphates, while dental caries and osteoporosis mean a partial decalcification of teeth and bones, respectively, that results in replacement of a less soluble and harder biological apatite by more soluble and softer calcium hydrogenphosphates. Therefore, the processes of both normal and pathological calcifications are just an in vivo crystallization of calcium orthophosphates. Similarly, dental caries and osteoporosis might be considered an in vivo dissolution of calcium orthophosphates. Thus, calcium orthophosphates hold a great significance for humankind, and in this paper, an overview on the current knowledge on this subject is provided. PMID:23507744

  14. Calcium Hydroxylapatite

    PubMed Central

    Yutskovskaya, Yana Alexandrovna; Philip Werschler, WM.

    2015-01-01

    Background: Calcium hydroxylapatite is one of the most well-studied dermal fillers worldwide and has been extensively used for the correction of moderate-to-severe facial lines and folds and to replenish lost volume. Objectives: To mark the milestone of 10 years of use in the aesthetic field, this review will consider the evolution of calcium hydroxylapatite in aesthetic medicine, provide a detailed injection protocol for a global facial approach, and examine how the unique properties of calcium hydroxylapatite provide it with an important place in todays market. Methods: This article is an up-to-date review of calcium hydroxylapatite in aesthetic medicine along with procedures for its use, including a detailed injection protocol for a global facial approach by three expert injectors. Conclusion: Calcium hydroxylapatite is a very effective agent for many areas of facial soft tissue augmentation and is associated with a high and well-established safety profile. Calcium hydroxylapatite combines high elasticity and viscosity with an ability to induce long-term collagen formation making it an ideal agent for a global facial approach. PMID:25610523

  15. Forest vegetation monitoring and foliar chemistry of red spruce and red maple at Acadia National Park in Maine.

    PubMed

    Wiersma, G Bruce; Elvir, Jose Alexander; Eckhoff, Janet D

    2007-03-01

    The USDA Forest Service Forest Health Monitoring (FHM) program indicators, including forest mensuration, crown condition classification, and damage and mortality indicators were used in the Cadillac Brook and Hadlock Brook watershed forests at Acadia National Park (ANP) along coastal Maine. Cadillac Brook watershed burned in a wildfire in 1947. Hadlock Brook watershed, undisturbed for several centuries, serves as the reference site. These two small watersheds have been gauged and monitored at ANP since 1998 as part of the Park Research and Intensive Monitoring of Ecosystems Network (PRIMENet). Forest vegetation at Hadlock Brook was dominated by late successional species such as Acer saccharum, Fagus grandifolia, Betula alleghaniensis, Acer rubrum and Picea rubens. Forest vegetation at Cadillac Brook, on the other hand, was younger and more diverse and included those species found in Hadlock as well as early successional species such as Betula papyrifera and Populus grandidentata. Differences in forest species composition and stand structure were attributed to the severe wildfire that affected the Cadillac Brook watershed. Overall, the forests at these ANP watersheds were healthy with a low percentage (Foliar nitrogen (N) concentrations were higher in A. rubrum and P. rubens trees growing in Hadlock Brook watershed, but differences were significant only for P. rubens. Foliar aluminum (Al) concentrations were also higher in both species growing in Hadlock Brook watershed but differences were significant only for A. rubrum. Foliar calcium (Ca) and manganese (Mn) concentrations, on the other hand, were significantly lower in Hadlock Brook watershed for both species. Foliar potassium (K) was significantly higher for P. rubens growing in Hadlock Brook. No differences in foliar concentrations of magnesium (Mg), phosphorus (P), boron (B), copper (Cu) and lead (Pb) were found between watersheds. The higher foliar N concentrations as well as higher foliar concentrations of Ca and Al might indicate early stages of N saturation and acidification in Hadlock Brook watershed as also suggested by Hadlock Brook stream N flux data in published PRIMENet studies at ANP. PMID:17180435

  16. Management of Pratylenchus penetrans on Oriental Lilies with Drip and Foliar-applied Nematicides.

    PubMed

    Westerdahl, B B; Giraud, D; Radewald, J D; Anderson, C A; Darso, J

    1993-12-01

    Pratylenchus penetrans is a pest for producers of oriental lilies in northern California. Concern over groundwater contamination from 1,2-dichloropropane following shank injections of 1,3-dichloropropene-l,2-dichloropropane mixture and granular applications of aldicarb prompted testing for alternative methods of controlling P. penetrans. In field trials, nematicides applied by drip irrigation (ethoprop, fenamiphos, oxamyl, sodium tetrathiocarbonate, water extracts of marigold and vetch, and 1,3-D plus emulsifier) were tested with and without foliar applications of oxamyl. Nematode populations were reduced (P = 0.05) relative to controls in soil or roots on one or more sampling dates by all drip-applied nematicides except the plant extracts. On some sampling dates, additional reductions (P = 0.05) occurred as a result of three foliar applications of oxamyl. Foliar-applied oxamyl alone also reduced (P = 0.05) nematodes in soil or roots. Lily bulb weight was not affected (P = 0.05) by chemical treatments. PMID:19279836

  17. Vine-shoot waste aqueous extract applied as foliar fertilizer to grapevines: Effect on amino acids and fermentative volatile content.

    PubMed

    Sánchez-Gómez, R; Garde-Cerdán, T; Zalacain, A; Garcia, R; Cabrita, M J; Salinas, M R

    2016-04-15

    The aim of this work was to study the influence of foliar applications of different wood aqueous extracts on the amino acid content of musts and wines from Airén variety; and to study their relationship with the volatile compounds formed during alcoholic fermentation. For this purpose, the foliar treatments proposed were a vine-shoot aqueous extract applied in one and two times, and an oak extract which was only applied once. Results obtained show the potential of Airén vine-shoot waste aqueous extracts to be used as foliar fertilizer, enhancing the wine amino acid content especially when they were applied once. Similar results were observed with the aqueous oak extract. Regarding wine fermentative volatile compounds, there is a close relationship between musts and their wines amino acid content allowing us to discuss about the role of proline during the alcoholic fermentation and the generation of certain volatiles. PMID:26616933

  18. Effect of Deficit Irrigation and Kaolin-based Foliar Reflectant Particle Film on Aroma of cv. Merlot (Vitis vinifera L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water deficit during development of red-skinned wine grape enhances berry composition for wine production but increases risk of fruit exposure to deleterious levels of heat and/or solar radiation. Foliar application of a kaolin-based particle film has been shown in many crops to alleviate stress sym...

  19. Stimulation of short-term plant growth by glycerol applied as foliar sprays and drenches under greenhouse conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar and drench applications of glycerol were tested at 0, 0.1, 5, 10, 25, and 50 ml.l-1 on Chantenay carrot (Daucus carota L.) family Apiaceae. Certain glycerol levels, especially the 1 to 10 ml.L-1 treatments, substantially increased fresh and dry weights of carrots sprayed twice over a 60-day...

  20. Calcium pyrophosphate arthritis

    MedlinePLUS

    Calcium pyrophosphate dihydrate deposition disease; CPPD disease; Acute CPPD arthritis; Pseudogout ... Calcium pyrophosphate arthritis is caused by the collection of salt called calcium pyrophosphate dihydrate (CPPD). The buildup ...

  1. Citrate-mediated release of aurintricarboxylic acid from a calcium alginate complex: implications for intravaginal HIV chemoprophylaxis and related applications.

    PubMed

    Fong, Krystin; Smith, Timothy J

    2009-01-01

    Factors associated with the intravaginal release of an anti-HIV agent from an alginate complex were considered. Among these is citrate associated with prostatic fluid. This study demonstrates that citrate, at a physiologically appropriate concentration, facilitates the release of an anti-HIV polymer from a calcium alginate complex. The release of the agent can be modified by the concentration of the calcium and alginate in the complex. These results suggest that seminal and prostatic fluid can be considered in the design of an intravaginal system for HIV chemoprophylaxis. PMID:19235046

  2. Calcium orthophosphates in dentistry.

    PubMed

    Dorozhkin, Sergey V

    2013-06-01

    Dental caries, also known as tooth decay or a cavity, remains a major public health problem in the most communities even though the prevalence of disease has decreased since the introduction of fluorides for dental care. Therefore, biomaterials to fill dental defects appear to be necessary to fulfill customers' needs regarding the properties and the processing of the products. Bioceramics and glass-ceramics are widely used for these purposes, as dental inlays, onlays, veneers, crowns or bridges. Calcium orthophosphates belong to bioceramics but they have some specific advantages over other types of bioceramics due to a chemical similarity to the inorganic part of both human and mammalian bones and teeth. Therefore, calcium orthophosphates (both alone and as components of various formulations) are used in dentistry as both dental fillers and implantable scaffolds. This review provides brief information on calcium orthophosphates and describes in details current state-of-the-art on their applications in dentistry and dentistry-related fields. Among the recognized dental specialties, calcium orthophosphates are most frequently used in periodontics; however, the majority of the publications on calcium orthophosphates in dentistry are devoted to unspecified "dental" fields. PMID:23468163

  3. Foliar nutrient status of Pinus ponderosa exposed to ozone and acid rain

    SciTech Connect

    Anderson, P.D.; Houpis, J.L.J. )

    1991-05-01

    A direct effect of foliar exposure to acid rain may be increased leaching of nutrient elements. Ozone exposure, through degradation of the cuticle and cellular membranes, may also result in increased nutrient leaching. To test these hypotheses, the foliar concentrations of 13 nutrient elements were monitored for mature branches of three clones of Pinus ponderosa exposed to ozone and/or acid rain. The three clones represented three distinct levels of phenotypic vigor. Branches were exposed to charcoal filtered, ambient, or 2 x ambient concentrations of ozone and received no acid rain (NAP), pH 5.1 rain (5.1), or pH 3.0 (3.0) rain. Following 10 months of continuous ozone exposure and 3 months of weekly rain applications, the concentrations of P and Mg differed significantly among rain treatments with a ranking of: 5.1 < NAP < 3.0. The S concentration increased with rain application regardless of pH. For the clones of moderate and low vigor, the concentration of N decreased with increasing rain acidity. There was no evidence of significant ozone or ozone x acid rain response. Among the three families, high phenotypic vigor was associated with significantly greater concentrations of N, P, K, Mg, B and An. These results indicate generally negligible leaching as a result of exposure to acid rain and/or ozone for one growing season. Increases in foliar concentrations of S, Mg and P are possibly the result of evaporative surface deposition from the rain solution.

  4. Soil versus foliar iodine fertilization as a biofortification strategy for field-grown vegetables.

    PubMed

    Lawson, Patrick G; Daum, Diemo; Czauderna, Roman; Meuser, Helmut; Härtling, Joachim W

    2015-01-01

    Iodine (I) biofortification of vegetables by means of soil and foliar applications was investigated in field experiments on a sandy loam soil. Supply of iodine to the soil in trial plots fertilized with potassium iodide (KI) and potassium iodate directly before planting (0, 1.0, 2.5, 7.5, and 15 kg I ha(-1)) increased the iodine concentration in the edible plant parts. The highest iodine accumulation levels were observed in the first growing season: In butterhead lettuce and kohlrabi the desired iodine content [50-100 μg I (100 g FM)(-1)] was obtained or exceeded at a fertilizer rate of 7.5 kg IO3 (-)-I ha(-1) without a significant yield reduction or impairment of the marketable quality. In contrast, supplying KI at the same rate resulted in a much lower iodine enrichment and clearly visible growth impairment. Soil applied iodine was phytoavailable only for a short period of time as indicated by a rapid decline of CaCl2-extractable iodine in the top soil. Consequently, long-term effects of a one-time iodine soil fertilization could not be observed. A comparison between the soil and the foliar fertilization revealed a better performance of iodine applied aerially to butterhead lettuce, which reached the desired iodine accumulation in edible plant parts at a fertilizer rate of 0.5 kg I(-)-I ha(-1). In contrast, the iodine content in the tuber of sprayed kohlrabi remained far below the targeted range. The results indicate that a sufficient spreading of iodine applied on the edible plant parts is crucial for the efficiency of the foliar approach and leafy vegetables are the more suitable target crops. The low iodine doses needed as well as the easy and inexpensive application may favor the implementation of foliar sprays as the preferred iodine biofortification strategy in practice. PMID:26157445

  5. Soil versus foliar iodine fertilization as a biofortification strategy for field-grown vegetables

    PubMed Central

    Lawson, Patrick G.; Daum, Diemo; Czauderna, Roman; Meuser, Helmut; Härtling, Joachim W.

    2015-01-01

    Iodine (I) biofortification of vegetables by means of soil and foliar applications was investigated in field experiments on a sandy loam soil. Supply of iodine to the soil in trial plots fertilized with potassium iodide (KI) and potassium iodate directly before planting (0, 1.0, 2.5, 7.5, and 15 kg I ha-1) increased the iodine concentration in the edible plant parts. The highest iodine accumulation levels were observed in the first growing season: In butterhead lettuce and kohlrabi the desired iodine content [50–100 μg I (100 g FM)-1] was obtained or exceeded at a fertilizer rate of 7.5 kg IO3--I ha-1 without a significant yield reduction or impairment of the marketable quality. In contrast, supplying KI at the same rate resulted in a much lower iodine enrichment and clearly visible growth impairment. Soil applied iodine was phytoavailable only for a short period of time as indicated by a rapid decline of CaCl2-extractable iodine in the top soil. Consequently, long-term effects of a one-time iodine soil fertilization could not be observed. A comparison between the soil and the foliar fertilization revealed a better performance of iodine applied aerially to butterhead lettuce, which reached the desired iodine accumulation in edible plant parts at a fertilizer rate of 0.5 kg I--I ha-1. In contrast, the iodine content in the tuber of sprayed kohlrabi remained far below the targeted range. The results indicate that a sufficient spreading of iodine applied on the edible plant parts is crucial for the efficiency of the foliar approach and leafy vegetables are the more suitable target crops. The low iodine doses needed as well as the easy and inexpensive application may favor the implementation of foliar sprays as the preferred iodine biofortification strategy in practice. PMID:26157445

  6. Application of acidic calcium sulfate and e-polylysine to pre-rigor beef rounds for reduction of pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foodborne illness continues to be a serious public health problem and is a major concern for the United States food industry. This study evaluated the effectiveness of warm solutions of acidic calcium sulfate (ACS), lactic acid (LA), episolon-polylysine (EPL), ACS plus EPL, and sterile distilled wa...

  7. LOW CONCENTRATION MERCURY SORPTION MECHANISMS AND CONTROL BY CALCIUM-BASED SORBENTS; APPLICATION IN COAL-FIRED PROCESSES

    EPA Science Inventory

    The capture of elemental mercury (Hgo) and mercuric chloride (HgCl2) by three types of calcium (Ca)-based sorbents was examined in this bench-scale study under conditions prevalent in coal fired utilities. Ca-based sorbent performances were compared to that of an activated carbon...

  8. Application of Foraminiferal Calcium Carbonate Chemistry to Proxy Past Ocean Conditions: key roles of Biomineral Formation and Dissolution

    NASA Astrophysics Data System (ADS)

    Elderfield, H.

    2001-12-01

    The use of the shell chemistry of foraminiferal calcite and aragonite for seawater paleothermometry and paleochemistry rests on confidence in the calibrations established to link metal uptake or isotope fractionation by the marine biogenic calcium carbonate to modern seawater composition. The early pioneering work in this field led to a period of application, principally of the establishment and expansion of stable oxygen and carbon isotope studies. But new work on trace metals in foraminifera has led to an upsurge of interest in, and reappraisal of, what controls metal uptake and the extent to which foraminifera do a good a job in recording and revealing the ocean's secrets. Two issues are considered: (i) understanding how secretion by the organism takes place and the chemical consequences; (ii) how dissolution changes the initial chemistry. The early work on ultrastructure shows that different, often progressive, layers are formed ranging from anhedral microgranules to euhedral crystallites; and that there is sequential and preferential dissolution of the different textural forms. This forms some basis for understanding, for example, the heterogeneity in foraminiferal Mg/Ca and how this is affected by dissolution. In general, warmer species (higher Mg/Ca) show greatest 104 line broadening and depth (or carbonate ion) related dissolution is accompanied by a decrease both in Mg/Ca and line broadening. Variation in calcification rate has been linked to changes in carbon isotope and Sr/Ca, perhaps through a carbonate ion effect. This is also seen from size fraction data. There is also variability in shell mass both from initial calcification history and from dissolution, and both affect shell chemistry. Shell mass is also associated with changes in normalised size and accompanied by chemical changes. One clear effect of Mg heterogeneity is in its effect on calibrations for thermometry and the extent to which phase differences between temperature (dissolution-corrected Mg/Ca) and ice volume (temperature-corrected oxygen isotopes) can be defined. Most paleoceanographic proxies are complex and are affected by primary and secondary factors which is why multi-proxy approached are increasingly used. Understanding why and how foraminifera incorporate trace elements through biological mineralization will help aid expansion of this important field.

  9. Calcium and bones

    MedlinePLUS

    Bone strength and calcium ... calcium (as well as phosphorus) to make healthy bones. Bones are the main storage site of calcium in ... your body does not absorb enough calcium, your bones can get weak or will not grow properly. ...

  10. Calcium cyanide

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS You are here : EPA Home Research Environmental Assessment IRIS IRIS Summaries Redirect Page As of September 28 , 2010 , the assessment summary for calcium cyanide is included in th

  11. Calcium cyanide

    Integrated Risk Information System (IRIS)

    Jump to main content . Integrated Risk Information System Recent Additions | Contact Us Search : All EPA IRIS • You are here : EPA Home • Research • Environmental Assessment • IRIS • IRIS Summaries Redirect Page As of September 28 , 2010 , the assessment summary for calcium cyanide is included in th

  12. Project Calcium

    SciTech Connect

    Hurley, J.P.; Benson, S.A.; Erickson, T.A.; Allan, S.E.; Bieber, J.

    1992-09-01

    Fouling problems in utility boilers have been classified into two principal types: high-temperature and low-temperature fouling. A multiclient-sponsored program was initiated at the Energy and Environmental Research Center (EERC) to better understand the causes of low-temperature fouling when burning high-calcium western US coals. The goals of Project Calcium were to define the low-temperature deposition problem, identify the calcium-based components that are responsible for the formation of the deposits, develop ways to predict their formation, and identify possible methods to mitigate the formation of these deposits. To achieve the goals of Project Calcium, detailed sampling of utility boilers and laboratory-scale studies coupled with state-of-the-art methods to determine the inorganic components in coals and coal ash-derived materials were conducted. Boiler Sampling was also performed. The work involved sampling coal, entrained ash, deposits and slags from five full-scale utility boilers combined with detailed advanced characterization of the materials. The results of this work aided in identifying the key phenomena to focus the laboratory studies and in model verification. Field testing was conducted at three utilities.

  13. Molecular mechanisms of foliar water uptake in a desert tree.

    PubMed

    Yan, Xia; Zhou, Maoxian; Dong, Xicun; Zou, Songbing; Xiao, Honglang; Ma, Xiao-Fei

    2015-01-01

    Water deficits severely affect growth, particularly for the plants in arid and semiarid regions of the world. In addition to precipitation, other subsidiary water, such as dew, fog, clouds and small rain showers, may also be absorbed by leaves in a process known as foliar water uptake. With the severe scarcity of water in desert regions, this process is increasingly becoming a necessity. Studies have reported on physical and physiological processes of foliar water uptake. However, the molecular mechanisms remain less understood. As major channels for water regulation and transport, aquaporins (AQPs) are involved in this process. However, due to the regulatory complexity and functional diversity of AQPs, their molecular mechanism for foliar water uptake remains unclear. In this study, Tamarix ramosissima, a tree species widely distributed in desert regions, was investigated for gene expression patterns of AQPs and for sap flow velocity. Our results suggest that the foliar water uptake of T. ramosissima occurs in natural fields at night when the humidity is over a threshold of 85 %. The diurnal gene expression pattern of AQPs suggests that most AQP gene expressions display a circadian rhythm, and this could affect both photosynthesis and transpiration. At night, the PIP2-1 gene is also upregulated with increased relative air humidity. This gene expression pattern may allow desert plants to regulate foliar water uptake to adapt to extreme drought. This study suggests a molecular basis of foliar water uptake in desert plants. PMID:26567212

  14. Molecular mechanisms of foliar water uptake in a desert tree

    PubMed Central

    Yan, Xia; Zhou, Maoxian; Dong, Xicun; Zou, Songbing; Xiao, Honglang; Ma, Xiao-Fei

    2015-01-01

    Water deficits severely affect growth, particularly for the plants in arid and semiarid regions of the world. In addition to precipitation, other subsidiary water, such as dew, fog, clouds and small rain showers, may also be absorbed by leaves in a process known as foliar water uptake. With the severe scarcity of water in desert regions, this process is increasingly becoming a necessity. Studies have reported on physical and physiological processes of foliar water uptake. However, the molecular mechanisms remain less understood. As major channels for water regulation and transport, aquaporins (AQPs) are involved in this process. However, due to the regulatory complexity and functional diversity of AQPs, their molecular mechanism for foliar water uptake remains unclear. In this study, Tamarix ramosissima, a tree species widely distributed in desert regions, was investigated for gene expression patterns of AQPs and for sap flow velocity. Our results suggest that the foliar water uptake of T. ramosissima occurs in natural fields at night when the humidity is over a threshold of 85 %. The diurnal gene expression pattern of AQPs suggests that most AQP gene expressions display a circadian rhythm, and this could affect both photosynthesis and transpiration. At night, the PIP2-1 gene is also upregulated with increased relative air humidity. This gene expression pattern may allow desert plants to regulate foliar water uptake to adapt to extreme drought. This study suggests a molecular basis of foliar water uptake in desert plants. PMID:26567212

  15. Foliar or root exposures to smelter particles: consequences for lead compartmentalization and speciation in plant leaves.

    PubMed

    Schreck, Eva; Dappe, Vincent; Sarret, Graldine; Sobanska, Sophie; Nowak, Dorota; Nowak, Jakub; Stefaniak, El?bieta Anna; Magnin, Valrie; Ranieri, Vincent; Dumat, Camille

    2014-04-01

    In urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results show that Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO4, chemical forms that were also observed in pristine particles, new species were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO3. In rye-grass, the changes in Pb speciation were even more egregious: Pb-cell wall and Pb-organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to better assess the health risks involved. PMID:24508855

  16. Applications of calcium electroporation to effective apoptosis induction in fibrosarcoma cells and stimulation of normal muscle cells.

    PubMed

    Zielichowska, Anna; Daczewska, Małgorzata; Saczko, Jolanta; Michel, Olga; Kulbacka, Julita

    2016-06-01

    The electroporation (EP) supports various types of anticancer therapies by the selective transport of cytostatics. Increase in intracellular calcium level by EP may be a new approach to fibrosarcoma treatment. Calcium is one of the most important factors of cell proliferation, differentiation and cell death (apoptosis or necrosis). Calcium level balanced by electroporation can cause different effects on normal and pathological cells. The efficiency and safety of electroporation combined with Ca(2+) ions were examined in our study. The two muscle cell lines were used: normal rat skeletal muscle cells - L6 and cancer muscle cells - Wehi-164 (fibrosarcoma). Two CaCl2 concentrations were tested: 0.5mM and 5mM combined with EP parameters: 1000V/cm, 1200V/cm, and 1500V/cm. The results show that EP supported by Ca(2+) is cytotoxic for Wehi-164 cells and simultaneously safe for normal muscle cells. The main type of cell death - apoptosis - was confirmed by Tunnel and Annexin V/PI assay. Additionally, sPLA2 pro-tumorigenic influence was proved by immunocytochemistry. Moreover, EP with 0.5mM of Ca(2+) slightly stimulates the normal muscle cells - L6 to increase proliferation. PMID:26874618

  17. Potentiostatic pulse-deposition of calcium phosphate on magnesium alloy for temporary implant applications--an in vitro corrosion study.

    PubMed

    Kannan, M Bobby; Wallipa, O

    2013-03-01

    In this study, a magnesium alloy (AZ91) was coated with calcium phosphate using potentiostatic pulse-potential and constant-potential methods and the in vitro corrosion behaviour of the coated samples was compared with the bare metal. In vitro corrosion studies were carried out using electrochemical impedance spectroscopy and potentiodynamic polarization in simulated body fluid (SBF) at 37 C. Calcium phosphate coatings enhanced the corrosion resistance of the alloy, however, the pulse-potential coating performed better than the constant-potential coating. The pulse-potential coating exhibited ~3 times higher polarization resistance than that of the constant-potential coating. The corrosion current density obtained from the potentiodynamic polarization curves was significantly less (~60%) for the pulse-deposition coating as compared to the constant-potential coating. Post-corrosion analysis revealed only slight corrosion on the pulse-potential coating, whereas the constant-potential coating exhibited a large number of corrosion particles attached to the coating. The better in vitro corrosion performance of the pulse-potential coating can be attributed to the closely packed calcium phosphate particles. PMID:25427473

  18. Role of calcium in gravity perception of plant roots

    NASA Technical Reports Server (NTRS)

    Evans, Michael L.

    1986-01-01

    Calcium ions may play a key role in linking graviperception by the root cap to the asymmetric growth which occurs in the elongation zone of gravistimulated roots. Application of calcium-chelating agents to the root cap inhibits gravitropic curvature without affecting growth. Asymmetric application of calcium to one side of the root cap induces curvature toward the calcium source, and gravistimulation induces polar movement of applied (Ca-45)(2+) across the root cap toward the lower side. The action of calcium may be linked to auxin movement in roots since: (1) auxin transport inhibitors interfere both with gravitropic curvature and graviinduced polar calcium movement and (2) asymmetric application of calcium enhances auxin movement across the elongation zone of gravistimulated roots. Indirect evidence indicates that the calcium-modulated regulator protein, calmodulin, may be involved in either the transport or action of calcium in the gravitropic response mechanism of roots.

  19. Calcium and Vitamin D

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium is required for the bone formation phase of bone remodeling. Typically about 5 nmol (200 mg) of calcium is removed from the adult skeleton and replaced each day. To supply this amount, one would need to consume about 600 mg of calcium, since calcium is not very efficiently absorbed. Calcium ...

  20. Complexometric Determination of Calcium

    NASA Astrophysics Data System (ADS)

    Nielsen, S. Suzanne

    Ethylenediaminetetraacetate (EDTA) complexes with numerous mineral ions, including calcium and magnesium. This reaction can be used to determine the amount of these minerals in a sample by a complexometric titration. Endpoints in the titration are detected using indicators that change color when they complex with mineral ions. Calmagite and eriochrome black T (EBT) are such indicators that change from blue to pink when they complex with calcium and magnesium. In the titration of a mineral-containing solution with EDTA, the solution turns from pink to blue at the endpoint with either indicator. The pH affects a complexometric EDTA titration in several ways, and must be carefully controlled. A major application of EDTA titration is testing the hardness of water, for which the method described is an official one (Standard Methods for the Examination of Water and Wastewater, Method 2340C; AOAC Method 920.196).

  1. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence.

    PubMed

    Tian, Shengke; Lu, Lingli; Xie, Ruohan; Zhang, Minzhe; Jernstedt, Judith A; Hou, Dandi; Ramsier, Cliff; Brown, Patrick H

    2014-01-01

    Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (?-XRF) to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, ?-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO4 alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant "GroZyme" resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using ?-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower. PMID:25653663

  2. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence

    DOE PAGESBeta

    Tian, Shengke; Lu, Lingli; Xie, Ruohan; Zhang, Minzhe; Jernstedt, Judith A.; Hou, Dandi; Ramsier, Cliff; Brown, Patrick H.

    2015-01-21

    Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF) to visualize Zn withinmore » the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO₄ alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant “GroZyme” resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using μ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower.« less

  3. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence

    PubMed Central

    Tian, Shengke; Lu, Lingli; Xie, Ruohan; Zhang, Minzhe; Jernstedt, Judith A.; Hou, Dandi; Ramsier, Cliff; Brown, Patrick H.

    2014-01-01

    Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF) to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO4 alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant “GroZyme” resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using μ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower. PMID:25653663

  4. Calcium and bones (image)

    MedlinePLUS

    Calcium is one of the most important minerals for the growth, maintenance, and reproduction of the human ... body, are continually being re-formed and incorporate calcium into their structure. Calcium is essential for the ...

  5. Coronary Calcium Scan

    MedlinePLUS

    ... the NHLBI on Twitter. What Is a Coronary Calcium Scan? A coronary calcium scan is a test ... you have calcifications in your coronary arteries. Coronary Calcium Scan Figure A shows the position of the ...

  6. Calcium source (image)

    MedlinePLUS

    Getting enough calcium to keep bones from thinning throughout a person's life may be made more difficult if that person has ... as a tendency toward kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also effects the ...

  7. Calcium carbonate overdose

    MedlinePLUS

    Calcium carbonate is an ingredient that is commonly found in antacids (for heartburn) and some dietary supplements. Calcium carbonate overdose occurs when someone accidentally or intentionally takes ...

  8. Non-destructive estimation of foliar carotenoid content of tree species using merged vegetation indices.

    PubMed

    Fassnacht, Fabian E; Stenzel, Stefanie; Gitelson, Anatoly A

    2015-03-15

    Leaf pigment content is an important indicator of plant status and can serve to assess the vigor and photosynthetic activity of plants. The application of spectral information gathered from laboratory, field and remote sensing-based spectrometers to non-destructively assess total chlorophyll (Chl) content of higher plants has been demonstrated in earlier studies. However, the precise estimation of carotenoid (Car) content with non-destructive spectral measurements has so far not reached accuracies comparable to the results obtained for Chl content. Here, we examined the potential of a recently developed angular vegetation index (AVI) to estimate total foliar Car content of three tree species. Based on an iterative search of all possible band combinations, we identified a best candidate AVIcar. The identified index showed quite close but essentially not linear relation with Car contents of the examined species with increasing sensitivity to high Car content and a lack of sensitivity to low Car content for which earlier proposed vegetation indices (VI) performed better. To make use of the advantages of both VI types, we developed a simple merging procedure, which combined the AVIcar with two earlier proposed carotenoid indices. The merged indices had close linear relationship with total Car content and outperformed all other examined indices. The merged indices were able to accurately estimate total Car content with a percental root mean square error (%RMSE) of 8.12% and a coefficient of determination of 0.88. Our findings were confirmed by simulations using the radiative transfer model PROSPECT-5. For simulated data, the merged indices again showed a quasi linear relationship with Car content. This strengthens the assumption that the proposed merged indices have a general ability to accurately estimate foliar Car content. Further examination of the proposed merged indices to estimate foliar Car content of other plant species is desirable to prove the general applicability of the index for non-destructive estimation of Car from leaf reflectance data. PMID:25512167

  9. Report on the Study of Radiation Damage in Calcium Fluoride and Magnesium Fluoride Crystals for use in Excimer Laser Applications

    SciTech Connect

    1999-10-04

    A study was performed to investigate the effects of radiation damage in calcium fluoride and magnesium fluoride crystals caused by gamma rays and UV photons from excimer lasers. The purpose was to study and correlate the damage caused by these two different mechanisms in various types of material used for fabricating optical elements in high power excimer lasers and lens systems of lithography tools. These optical systems are easily damaged by the laser itself, and it is necessary to use only the most radiation resistant materials for certain key elements. It was found that a clear correlation exists between the, radiation induced damage caused by high energy gamma rays and that produced by UV photons from the excimer laser. This correlation allows a simple procedure to be developed to select the most radiation resistant material at the ingot level, which would be later used to fabricate various components of the optical system. This avoids incurring the additional cost of fabricating actual optical elements with material that would later be damaged under prolonged use. The result of this screening procedure can result in a considerable savings in the overall cost of the lens and laser system.

  10. Preparation of biomorphic porous calcium titanate and its application for preconcentration of nickel in water and food samples.

    PubMed

    Zhang, Dong; Wang, Min; Ren, Guang-jun; Song, En-jun

    2013-12-01

    Biomorphic porous nanocrystalline-calcium titanate (SPCTO) was successfully prepared using the sol-gel method and with sorghum straw as the template. Characterization was conducted through XRD, SEM and FTIR. The ability of SPCTO to adsorb nickel ion in water was assessed. Elution and regeneration conditions, as well as the thermodynamics and kinetics of nickel adsorption, were also investigated. The result showed that the sorbent by the sol-gel template method was porous and has a perovskite structure with an average particle diameter of 26 nm. The nickel ion could be quantitatively retained at a pH value range of 4-8, but the adsorbed nickel ion could be completely eluted using 2 mol L(-1) HNO3. The adsorption capacity of SPCTO for nickel was found to be 51.814 mg g(-1) and the adsorption behavior followed a Langmuir adsorption isotherm and a pseudo-second-order kinetic model. The enthalpy change (?H) of the adsorption process was 33.520 kJ mol(-1). At various temperatures, Gibbs free energy changes (?G) were negative, and entropy changes (?S) were positive. The activation energy (Ea) was 25.291 kJ mol(-1) for the adsorption. These results demonstrate that the adsorption was an endothermic and spontaneous physical process. This same method has been successfully applied in the preconcentration and determination of nickel in water and food samples with good results. PMID:24094175

  11. Foliar biofilms of Burkholderia pyrrocinia FP62 on geraniums

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofilm formation on foliar surfaces is commonly associated with plants in water-saturated environments (e.g. tropics or modified environments). On most leaf surfaces bacteria are thought to reside in aggregates with limited production of an exopolysaccharide (EPS) matrix. However, the biocontrol ag...

  12. A generic theoretical model for biological control of foliar plant diseases.

    PubMed

    Jeger, M J; Jeffries, P; Elad, Y; Xu, X-M

    2009-01-21

    We have developed a generic modelling framework to understand the dynamics of foliar pathogen and biocontrol agent (BCA) populations in order to predict the likelihood of successful biocontrol in relation to the mechanisms involved. The model considers biocontrol systems for foliar pathogens only and, although it is most applicable to fungal BCA systems, does not address a specific biocontrol system. Four biocontrol mechanisms (competition, antibiosis, mycoparasitism and induced resistance) were included within the model rubric. Because of the wide range of mechanisms involved we use Trichoderma/Botrytis as an exemplar system. Qualitative analysis of the model showed that the rates of a BCA colonising diseased and/or healthy plant tissues and the time that the BCA remains active are two of the more important factors in determining the final outcome of a biocontrol system. Further evaluation of the model indicated that the dynamic path to the steady-state population levels also depends critically on other parameters such as the host-pathogen infection rate. In principle, the model can be extended to include other potential mechanisms, including spatio-temporal heterogeneity, fungicide effects, non-fungal BCA and strategies for BCA application, although with a cost in model tractability and ease of interpretation. PMID:18983855

  13. Controlling Foliar Disease with ZeroTol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ZeroTol is a disinfestant labeled for direct application on plants. Laboratory, field, and greenhouse experiments were performed to determine the rates and intervals in days between applications needed to control daylily rust. In laboratory trials, a very high rate was required to achieve 100% morta...

  14. Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA

    PubMed Central

    Momen, Bahram; Behling, Shawna J.; Lawrence, Greg B.; Sullivan, Joseph H.

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival. PMID:26291323

  15. Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

    USGS Publications Warehouse

    Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor, which can impede seedling survival.

  16. The use of laser light to enhance the uptake of foliar-applied substances into citrus (Citrus sinensis) leaves1

    PubMed Central

    Etxeberria, Ed; Gonzalez, Pedro; Fanton Borges, Ana; Brodersen, Craig

    2016-01-01

    Premise of the study: Uptake of foliar-applied substances across the leaf cuticle is central to world food production as well as for physiological investigations into phloem structure and function. Yet, despite the presence of stomata, foliar application as a delivery system can be extremely inefficient due to the low permeability of leaf surfaces to polar compounds. Methods: Using laser light to generate microscopic perforations in the leaf cuticle, we tested the penetration of several substances into the leaf, their uptake into the phloem, and their subsequent movement through the phloem tissue. Substances varied in their size, charge, and Stokes radius. Results: The phloem-mobile compounds 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG), lysine, Biocillin, adenosine triphosphate (ATP), trehalose, carboxyfluorescein-SE, and poly(amidomine) (PAMAM) dendrimer G-4 nanoparticles (4.5 nm in size) showed a high degree of mobility and were able to penetrate and be transported in the phloem. Discussion: Our investigation demonstrated the effectiveness of laser light technology in enhancing the penetration of foliar-applied substances into citrus leaves. The technology is also applicable to the study of phloem mobility of substances by providing a less invasive, highly repeatable, and more quantifiable delivery method. The implied superficial lesions to the leaf can be mitigated by applying a waxy coating. PMID:26819863

  17. Comparison of Rain-Fast Bait Stations Versus Foliar Bait Sprays for Control of Oriental Fruit Fly, Bactrocera dorsalis, in Papaya Orchards in Hawaii

    PubMed Central

    Piero, Jaime C.; Mau, Ronald F. L.; Vargas, Roger I.

    2010-01-01

    Bait stations represent an environmentally friendly attract-and-kill approach to fruit fly population suppression. Recently a novel, visually attractive, rain-fast bait station was developed in Hawaii for potential use against multiple species of pestiferous fruit flies. Here, we compared the efficacy of GF-120 NF Naturalyte Fruit Fly Bait applied either as foliar sprays or onto bait stations in reducing female oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), population density and level of fruit infestation in commercial papaya orchards in Hawaii. Trapping and infestation data were used as indicators of the effectiveness of the two bait application methods. For the first 10 weeks of the study, captures of female B. dorsalis in monitoring traps were significantly greater in control plots than in plots treated with foliar sprays or bait stations. Six weeks after the first bait spray, incidence of infestation (i.e. number of fruit with one or more B. dorsalis larvae) of quarter to half-ripe papaya fruit was reduced by 71.4% and 63.1% for plots with bait stations and foliar sprays, respectively, as compared to control plots. Twelve weeks after first spray, incidence of infestation was reduced by only 54.5% and 45.4% for plots with bait stations and foliar sprays, respectively, as compared to control plots. About 42% less GF-120 was used in orchard plots with bait stations compared to those subject to foliar sprays. The impact of field sanitation on the outcome is also discussed. The results indicate that bait stations can provide a simple, efficient, and economical method of applying insecticidal baits to control fruit flies and a safer alternative to foliar sprays. PMID:21067423

  18. Foliar application of nickel and copper on pecan performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mobilization and conversion of reserve nitrogen (N) is critical for pecans [Carya illinoinensis (Wang.) K. Koch] during early spring when trees begin growing actively. Conversion of N reserves to translocatable forms (amides, amino acids, ureides) is adversely affected by a nickel (Ni) shortage...

  19. Total phosphorous, calcium, aluminum and iron levels in Cecil soil after ten years of poultry litter application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poultry litter (PL) is a traditionally inexpensive and effective organic fertilizer to improve soil quality and agricultural productivity. However, there is concern with over application as this can lead to excess releases of nutrients, especially phosphorus, and metals into fresh water bodies resul...

  20. Effects of sampling method on foliar ? (13)C of Leymus chinensis at different scales.

    PubMed

    Liu, Yanjie; Li, Yan; Zhang, Lirong; Xu, Xingliang; Niu, Haishan

    2015-03-01

    Stable carbon isotope composition (? (13)C) usually shows a negative relationship with precipitation at a large scale. We hypothesized that sampling method affects foliar ? (13)C and its response pattern to precipitation. We selected 11 sites along a precipitation gradient in Inner Mongolia and collected leaves of Leymus chinensis with five or six replications repeatedly in each site from 2009 to 2011. Additionally, we collected leaves of L. chinensis separately from two types of grassland (grazed and fenced) in 2011. Foliar ? (13)C values of all samples were measured. We compared the patterns that foliar ? (13)C to precipitation among different years or different sample sizes, the differences of foliar ? (13)C between grazed and fenced grassland. Whether actual annual precipitation (AAP) or mean annual precipitation (MAP), it was strongly correlated with foliar ? (13)C every year. Significant difference was found between the slopes of foliar ? (13)C to AAP and MAP every year, among the slopes of foliar ? (13)C to AAP from 2009 to 2011. The more samples used at each site the lower and convergent P-values of the linear regression test between foliar ? (13)C and precipitation. Furthermore, there was significant lower foliar ? (13)C value in presence of grazed type than fenced type grassland. These findings provide evidence that there is significant effect of sampling method to foliar ? (13)C and its response pattern to precipitation of L. chinensis. Our results have valuable implications in methodology for future field sampling studies. PMID:25798224

  1. Influence of casein phosphopeptide-amorphous calcium phosphate application, smear layer removal, and storage time on resin-dentin bonding*

    PubMed Central

    Lin, Jun; Zheng, Wei-ying; Liu, Peng-ruo-feng; Zhang, Ning; Lin, Hui-ping; Fan, Yi-jing; Gu, Xin-hua; Vollrath, Oliver; Mehl, Christian

    2014-01-01

    The aim of this study is to evaluate the influence of Tooth Mousse (TM) application, smear layer removal, and storage time on resin-dentin microtensile bond strength (μTBS). Dentin specimens were divided into two groups: (1) smear layer covered; (2) smear layer removed using 15% EDTA for 90 s. In each group, half the specimens were treated once with TM for 60 min. After bonding procedures using a two-step self-etching adhesive (Clearfil SE Bond (CSE); Kuraray Medical, Tokyo, Japan), an all-in-one adhesive (G-Bond (GB); GC Corp, Tokyo, Japan), and a total-etch adhesive (Adper Single Bond 2 (SB); 3M ESPE, St. Paul, MN, USA), the specimens were stored for 3 d or 6 months in deionized water at 37 °C, and μTBS was tested and analyzed. With the exception of SB (no TM application) and GB, the μTBS was significantly increased for CSE and SB using EDTA pre-conditioning and 3 d of storage (P≤0.001). Bond strength of GB decreased significantly when using EDTA (3 d storage, P<0.05). TM application only increased the μTBS of GB (no EDTA) and SB (with EDTA) after 3 d (P≤0.02). Comparing the adhesives after 3 d of storage, CSE exhibited the greatest μTBS values followed by GB and SB (P≤0.02). The factors of adhesive, EDTA, and TM did not show any significant impact on μTBS when specimens were stored for 6 months (P>0.05). The additional application of TM and EDTA for cavity preparation seems only to have a short-term effect, and no influence on μTBS of dentin bonds after a period of 6 months. PMID:25001224

  2. Effects of foliar applied nickel on tomato plants. [Lycopersicon esculentum

    SciTech Connect

    Cash, R.C.; Leone, I.A.

    1987-01-01

    Shoot-applied nickel (Ni) treatments produced symptomatology, foliar Ni accumulation, and cytological changes in tomato (Lycopersicon esculentum Mill.) similar to those caused by treatments with root-applied nickel (Ni). Leaf damage resulting from 100 ..mu..g/ml foliar Ni-treatments consisted of interveinal chlorosis and spotting necrosis which appeared histologically as tissue collapse, cell clumping, and chloroplast disintegration. Shoot-treated plants accumulated more Ni in leaves than in roots; whereas the reverse was true in root-treated plants. Interference with root-to-shoot manganese translocation was attributed to attenuated vascular tissue and phloem blockage. Evidence of reduced nutrient transport and inhibited meristem activity due to Ni toxicity presents a potential for crop damage from excessive Ni in the atmosphere as well as in the soil environment.

  3. CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, CALCIUM CHLORIDE STORAGE BUILDING ON RIGHT WITH SA (SODA ASH) BUILDING IN RIGHT BACKGROUND. - Solvay Process Company, Calcium Chloride Plant, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  4. Identification of Fusarium virguliforme FvTox1-Interacting Synthetic Peptides for Enhancing Foliar Sudden Death Syndrome Resistance in Soybean

    PubMed Central

    Wang, Bing; Swaminathan, Sivakumar; Bhattacharyya, Madan K.

    2015-01-01

    Soybean is one of the most important crops grown across the globe. In the United States, approximately 15% of the soybean yield is suppressed due to various pathogen and pests attack. Sudden death syndrome (SDS) is an emerging fungal disease caused by Fusarium virguliforme. Although growing SDS resistant soybean cultivars has been the main method of controlling this disease, SDS resistance is partial and controlled by a large number of quantitative trait loci (QTL). A proteinacious toxin, FvTox1, produced by the pathogen, causes foliar SDS. Earlier, we demonstrated that expression of an anti-FvTox1 single chain variable fragment antibody resulted in reduced foliar SDS development in transgenic soybean plants. Here, we investigated if synthetic FvTox1-interacting peptides, displayed on M13 phage particles, can be identified for enhancing foliar SDS resistance in soybean. We screened three phage-display peptide libraries and discovered four classes of M13 phage clones displaying FvTox1-interacting peptides. In vitro pull-down assays and in vivo interaction assays in yeast were conducted to confirm the interaction of FvTox1 with these four synthetic peptides and their fusion-combinations. One of these peptides was able to partially neutralize the toxic effect of FvTox1 in vitro. Possible application of the synthetic peptides in engineering SDS resistance soybean cultivars is discussed. PMID:26709700

  5. Application of the specular and diffuse reflection analysis for in vitro diagnostics of dental erosion: correlation with enamel softening, roughness, and calcium release

    PubMed Central

    Rakhmatullina, Ekaterina; Bossen, Anke; Hschele, Christoph; Wang, Xiaojie; Beyeler, Barbara; Meier, Christoph; Lussi, Adrian

    2011-01-01

    We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r2 ? ?0.86) as well as calcium release (r2 ? ?0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r2 = 0.420.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo. PMID:22029364

  6. Validation of RP-HPLC method and stress degradation for the combination of metformin HCl, atorvastatin calcium and glimepiride: application to nanoparticles.

    PubMed

    Gite, Sandip; Patravale, Vandana

    2015-01-01

    A stability-indicating high-performance liquid chromatography (HPLC) procedure was developed for the determination of metformin HCl (MTH), atorvastatin calcium (AC) and glimepiride (GP) in combination and their main degradation products. The separation and quantization were achieved on a 5-m Qualisil gold, C18 column (4.6 mm 250 mm). The mobile phase selected was phosphate buffer (pH 2.9)-organic phase in proportion of 70:30. Organic phase consisted of methanol-acetonitrile (90:10) at a flow rate of 1 mL/min and detection of analytes was carried out at 230 nm. The method exhibited good linearity over the range of 10-60 g/mL for MTH, 2-20 g/mL for AC and 5-30 g/mL for GP. Square of the correlation coefficients was found to be >0.999. Various stress degradation studies were carried out in combination as per International Conference of Harmonization (ICH) guidelines for 4 h. The recovery and precision were determined in terms of intraday and interday precisions and expressed as relative standard deviations. These were <1 and <2%, respectively. Finally, the applicability of the method was evaluated in nanoparticle analysis of MTH, AC and GP as well as in stability studies of nanoformulation. PMID:26071607

  7. Application of the specular and diffuse reflection analysis for in vitro diagnostics of dental erosion: correlation with enamel softening, roughness, and calcium release

    NASA Astrophysics Data System (ADS)

    Rakhmatullina, Ekaterina; Bossen, Anke; Höschele, Christoph; Wang, Xiaojie; Beyeler, Barbara; Meier, Christoph; Lussi, Adrian

    2011-10-01

    We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r2 >= -0.86) as well as calcium release (r2 >= -0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r2 = 0.42-0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo.

  8. Application of the specular and diffuse reflection analysis for in vitro diagnostics of dental erosion: correlation with enamel softening, roughness, and calcium release.

    PubMed

    Rakhmatullina, Ekaterina; Bossen, Anke; Höschele, Christoph; Wang, Xiaojie; Beyeler, Barbara; Meier, Christoph; Lussi, Adrian

    2011-10-01

    We present assembly and application of an optical reflectometer for the analysis of dental erosion. The erosive procedure involved acid-induced softening and initial substance loss phases, which are considered to be difficult for visual diagnosis in a clinic. Change of the specular reflection signal showed the highest sensitivity for the detection of the early softening phase of erosion among tested methods. The exponential decrease of the specular reflection intensity with erosive duration was compared to the increase of enamel roughness. Surface roughness was measured by optical analysis, and the observed tendency was correlated with scanning electron microscopy images of eroded enamel. A high correlation between specular reflection intensity and measurement of enamel softening (r(2) ≥ -0.86) as well as calcium release (r(2) ≥ -0.86) was found during erosion progression. Measurement of diffuse reflection revealed higher tooth-to-tooth deviation in contrast to the analysis of specular reflection intensity and lower correlation with other applied methods (r(2) = 0.42-0.48). The proposed optical method allows simple and fast surface analysis and could be used for further optimization and construction of the first noncontact and cost-effective diagnostic tool for early erosion assessment in vivo. PMID:22029364

  9. No globally consistent effect of ectomycorrhizal status on foliar traits.

    PubMed

    Koele, Nina; Dickie, Ian A; Oleksyn, Jacek; Richardson, Sarah J; Reich, Peter B

    2012-11-01

    The concept that ectomycorrhizal plants have a particular foliar trait suite characterized by low foliar nutrients and high leaf mass per unit area (LMA) is widely accepted, but whether this trait suite can be generalized to all ectomycorrhizal clades is unclear. We identified 19 evolutionary clades of ectomycorrhizal plants and used a global leaf traits dataset comprising 11,466 samples across c. 3000 species to test whether there were consistent shifts in leaf nutrients or LMA with the evolution of ectomycorrhiza. There were no consistent effects of ectomycorrhizal status on foliar nutrients or LMA in the 17 ectomycorrhizal/non-ectomycorrhizal pairs for which we had sufficient data, with some ectomycorrhizal groups having higher and other groups lower nutrient status than non-ectomycorrhizal contrasts. Controlling for the woodiness of host species did not alter the results. Our findings suggest that the concepts of ectomycorrhizal plant trait suites should be re-examined to ensure that they are broadly reflective of mycorrhizal status across all evolutionary clades, rather than reflecting the traits of a few commonly studied groups, such as the Pinaceae and Fagales. PMID:22966750

  10. Methods in plant foliar volatile organic compounds research1

    PubMed Central

    Materić, Dušan; Bruhn, Dan; Turner, Claire; Morgan, Geraint; Mason, Nigel; Gauci, Vincent

    2015-01-01

    Plants are a major atmospheric source of volatile organic compounds (VOCs). These secondary metabolic products protect plants from high-temperature stress, mediate in plant–plant and plant–insect communication, and affect our climate globally. The main challenges in plant foliar VOC research are accurate sampling, the inherent reactivity of some VOC compounds that makes them hard to detect directly, and their low concentrations. Plant VOC research relies on analytical techniques for trace gas analysis, usually based on gas chromatography and soft chemical ionization mass spectrometry. Until now, these techniques (especially the latter one) have been developed and used primarily by physicists and analytical scientists, who have used them in a wide range of scientific research areas (e.g., aroma, disease biomarkers, hazardous compound detection, atmospheric chemistry). The interdisciplinary nature of plant foliar VOC research has recently attracted the attention of biologists, bringing them into the field of applied environmental analytical sciences. In this paper, we review the sampling methods and available analytical techniques used in plant foliar VOC research to provide a comprehensive resource that will allow biologists moving into the field to choose the most appropriate approach for their studies. PMID:26697273

  11. Calcium-Rich Foods

    MedlinePLUS

    ... 130 Waffle 80 g 47 Meat, fish and eggs Food Serving Size Calcium (mg) Egg 50 g 27 Red meat 120 g 7 ... foods Food Serving Size Calcium (mg) Quiche (cheese, eggs) 200 g 212 Omelette with cheese 120 g ...

  12. Calcium in diet

    MedlinePLUS

    ... Salmon and sardines canned with their soft bones Almonds, Brazil nuts, sunflower seeds, tahini, and dried beans ... greens = 220 mg of calcium 3 ounces of almonds = 210 mg of calcium Vitamin D is needed ...

  13. Calcium and magnesium disorders.

    PubMed

    Goff, Jesse P

    2014-07-01

    Hypocalcemia is a clinical disorder that can be life threatening to the cow (milk fever) and predisposes the animal to various other metabolic and infectious disorders. Calcium homeostasis is mediated primarily by parathyroid hormone, which stimulates bone calcium resorption and renal calcium reabsorption. Parathyroid hormone stimulates the production of 1,25-dihydroxyvitamin D to enhance diet calcium absorption. High dietary cation-anion difference interferes with tissue sensitivity to parathyroid hormone. Hypomagnesemia reduces tissue response to parathyroid hormone. PMID:24980727

  14. Calcium and Mitosis

    NASA Technical Reports Server (NTRS)

    Hepler, P.

    1983-01-01

    Although the mechanism of calcium regulation is not understood, there is evidence that calcium plays a role in mitosis. Experiments conducted show that: (1) the spindle apparatus contains a highly developed membrane system that has many characteristics of sarcoplasmic reticulum of muscle; (2) this membrane system contains calcium; and (3) there are ionic fluxes occurring during mitosis which can be seen by a variety of fluorescence probes. Whether the process of mitosis can be modulated by experimentally modulating calcium is discussed.

  15. Calcium and Your Child

    MedlinePLUS

    ... babies who don't get enough calcium and vitamin D (which aids in calcium absorption) are at increased risk for rickets. Rickets is a bone-softening disease that causes severe bowing of the legs, poor growth, and sometimes muscle pain and weakness. Calcium also ...

  16. Calcium and Vitamin D

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the roles of calcium and vitamin D in bone health. Calcium is required for the bone formation phase of bone remodeling and it also affects bone mass through its impact on the remodeling rate. Typically, about 5 nmol (200 mg) of calcium is removed from the adult skeleton and ...

  17. Chitosan/?-1,3-glucan/calcium phosphate ceramics composites--novel cell scaffolds for bone tissue engineering application.

    PubMed

    Przekora, Agata; Palka, Krzysztof; Ginalska, Grazyna

    2014-07-20

    Bone tissue engineering put emphasis on fabrication three-dimensional biodegradable porous scaffolds that possess ability to enhance adhesion, proliferation and differentiation of osteoblast cells, therefore supporting bone regeneration and functional bone tissue formation. The aim of this work was to fabricate novel tri-component scaffolds composed of chitosan, ?-1,3-glucan, and bioceramics and to evaluate their basic structural, mechanical, and biological properties. It should be noted that we are the first who describe fabrication and characterization of tri-component composites containing ?-1,3-glucan. Microstructure of novel composites was visualized by computed tomography scanning and SEM. Compressive strength and Young's modulus of the composites were evaluated by compression testing. The biocompatibility was assessed in vitro by cytotoxicity, cell attachment and cell proliferation tests using human foetal osteoblast cell line. Our results demonstrated that novel composites possess good compressive strength as the effect of polysaccharide components of scaffolds, are very elastic, are non-toxic, favourable to cell adhesion and promote cell proliferation. However, novel biomaterials revealed relatively low Young's modulus values. Thus, we infer that fabricated novel composites are promising materials for bone tissue engineering application as cell scaffolds to fill small bone losses rather than as massive bone fillers exposed to mechanical load. PMID:24815684

  18. Chitosan/?-1,3-glucan/calcium phosphate ceramics composites--novel cell scaffolds for bone tissue engineering application.

    TOXLINE Toxicology Bibliographic Information

    Przekora A; Palka K; Ginalska G

    2014-07-20

    Bone tissue engineering put emphasis on fabrication three-dimensional biodegradable porous scaffolds that possess ability to enhance adhesion, proliferation and differentiation of osteoblast cells, therefore supporting bone regeneration and functional bone tissue formation. The aim of this work was to fabricate novel tri-component scaffolds composed of chitosan, ?-1,3-glucan, and bioceramics and to evaluate their basic structural, mechanical, and biological properties. It should be noted that we are the first who describe fabrication and characterization of tri-component composites containing ?-1,3-glucan. Microstructure of novel composites was visualized by computed tomography scanning and SEM. Compressive strength and Young's modulus of the composites were evaluated by compression testing. The biocompatibility was assessed in vitro by cytotoxicity, cell attachment and cell proliferation tests using human foetal osteoblast cell line. Our results demonstrated that novel composites possess good compressive strength as the effect of polysaccharide components of scaffolds, are very elastic, are non-toxic, favourable to cell adhesion and promote cell proliferation. However, novel biomaterials revealed relatively low Young's modulus values. Thus, we infer that fabricated novel composites are promising materials for bone tissue engineering application as cell scaffolds to fill small bone losses rather than as massive bone fillers exposed to mechanical load.

  19. Calcium bioavailability from calcium fortified food products.

    PubMed

    Kohls, K

    1991-08-01

    The calcium balance of 12 presumed healthy human young adult subjects was assessed. Subjects consumed a constant laboratory-controlled diet supplemented with one of four calcium-fortified food products: orange juice (OJ), milk (M), experimental pasteurized processed cheese (T), soda (S), or a calcium carbonate plus vitamin D tablet (CC). Study length was 6 weeks with seven-day experimental periods (2-days allowed for adjustment with 5-days combined for purposes of analysis). All urine and fecal samples were collected by the subjects for the duration of the study. Blood samples were drawn at the end of each experimental period. Urine and fecal calcium contents were determined. Blood samples were analyzed for alkaline phosphatase. Results of this study indicate a higher fecal calcium content (mg/day) when subjects consumed CC and T, and when subjects consumed self-selected diets, than when given S, M, or OJ. Urinary calcium excretion was significantly lower when subjects consumed OJ than when they consumed M, T, or their self-selected diets. A significantly larger positive calcium balance was demonstrated when subjects consumed OJ as compared to T. Fecal transmit time did not vary significantly. Serum alkaline phosphatase was significantly lower when subjects consumed T than when they consumed self-selected diets. PMID:1765836

  20. Are correlations among foliar traits in ferns consistent with those in the seed plants?

    PubMed

    Karst, Amanda L; Lechowicz, Martin J

    2007-01-01

    Broad-based studies of gymnosperms and angiosperms reveal consistent and functionally significant correlations among foliar traits such as leaf mass per area (LMA), maximum photosynthetic rate (A(area)), foliar nitrogen (N(area)), foliar chlorophyll (Chl) and leaf longevity. To assess the generality of these relationships, we studied 20 fern species growing in the understorey of a temperate deciduous forest. We found that foliar N(area) increases with LMA, and that foliar N(area) and A(area) are positively correlated with one another, as are foliar N(area) and Chl. The ferns in general have very low LMA compared with most seed plants; A(area), N(area) and Chl are below median values for seed plants but are not extreme. Species with overwintering fronds have significantly higher LMA than species with fronds that senesce at the end of the growing season, as well as a significantly higher C : N ratio in frond tissue and relatively high foliar N on an areal basis. Correlations among foliar traits associated with gas exchange in these forest understorey ferns are in accordance with patterns reported for seed plants, suggesting a high degree of functional constraint on the interrelationships among key elements in foliar design. PMID:17204077

  1. Effect of dislodging techniques on foliar residue determination for agricultural crops.

    PubMed

    Bruce, E; Korpalski, S; Johnson, D; Klonne, D; Nagel, W; Holden, L; Lange, B

    2006-01-01

    The Agricultural Reentry Task Force (ARTF) conducted a study to determine whether different dislodgeable foliar residue (DFR) techniques had any effect on the amount of residues dislodged from the leaves of vegetable crops. Four previously employed techniques were evaluated with two chemicals (carbaryl and methomyl) on two crops (cabbage and lettuce). Carbaryl, a moderately water-soluble chemical, was applied at a rate of 2.0 lbs active ingredient/acre (lb ai/A) while methomyl, a highly water soluble chemical, was applied at a rate of 0.9 lb ai/A. One day after application, leaf punches were collected and the residues were dislodged following one of four techniques that differed in the number of dislodgings per sample, the duration of dislodging, the solution volume, and/or the type of solution used. The results indicated that three of the techniques gave similar results, whereas a fourth gave marginally lower results. PMID:16385393

  2. High-calcium coal combustion by-products: Engineering properties, ettringite formation, and potential application in solidification and stabilization of selenium and boron

    SciTech Connect

    Solem-Tishmack, J.K.; McCarthy, G.J.; Docktor, B.; Eylands, K.E.; Thompson, J.S.; Hassett, D.J.

    1995-04-01

    Four high-calcium coal combustion by-products (two pulverized coal fly ashes (PCFA), a flue gas desulfurization (FGD) residue, and an atmospheric fluidized bed combustion (AFBC) fly ash), were tested for engineering properties and ability to immobilize boron and selenium. These data are needed to explore high-volume utilization in engineered structure or in solidification/stabilization (S/S) technology. Strengths of cured pastes (91 days), varied from as much as 27 MPa (3,900 psi) for one of the PCFA specimens to 4.6 MPa (670 psi) for the FGD specimen. All of the coal by-product pastes developed more than the 0.34 MPa (50 psi) required for S/S applications. Ettringite formation is important to engineering properties and S/S mechanisms. XRD on plain specimens cured for 91 days indicated that the two PCFA pastes formed 5--6% ettringite, the FGD paste formed 22%, and the AFBC paste formed 32%. The hydrating PCFA pastes showed little expansion, the FGD paste contracted slightly, and the AFBC paste expanded by 2.9% over 91 days. Se and B were spiked into the mixing water as sodium selenite, selenate and borate, and for most pastes this had little effect on strength, workability, and expansion. Leaching of ground specimens (cured for 91 days) showed a generally positive correlation between the amount of ettringite formed and resistance to Se and B leaching. Se spiked as selenate was more readily leached than Se spiked as selenite. B showed a high level of fixation.

  3. Process for converting magnesium fluoride to calcium fluoride

    DOEpatents

    Kreuzmann, A.B.; Palmer, D.A.

    1984-12-21

    This invention is a process for the conversion of magnesium fluoride to calcium fluoride whereby magnesium fluoride is decomposed by heating in the presence of calcium carbonate, calcium oxide or calcium hydroxide. Magnesium fluoride is a by-product of the reduction of uranium tetrafluoride to form uranium metal and has no known commercial use, thus its production creates a significant storage problem. The advantage of this invention is that the quality of calcium fluoride produced is sufficient to be used in the industrial manufacture of anhydrous hydrogen fluoride, steel mill flux or ceramic applications.

  4. Foliar anthocyanin content - Sensitivity of vegetation indices using green reflectance

    NASA Astrophysics Data System (ADS)

    Vina, A.; Gitelson, A. A.

    2009-12-01

    The amount and composition of photosynthetic and non-photosynthetic foliar pigments varies primarily as a function of species, developmental and phenological stages, and environmental stresses. Information on the absolute and relative amounts of these pigments thus provides insights onto the physiological conditions of plants and their responses to stress, and has the potential to be used for evaluating plant species composition and diversity across broad geographic regions. Anthocyanins in particular, are non-photosynthetic pigments associated with the resistance of plants to environmental stresses (e.g., drought, low soil nutrients, high radiation, herbivores, and pathogens). As they absorb radiation primarily in the green region of the electromagnetic spectrum (around 540-560 nm), broad-band vegetation indices that use this region in their formulation will respond to their presence. We evaluated the sensitivity of three vegetation indices using reflectance in the green spectral region (the green Normalized Difference Vegetation Index, gNDVI, the green Chlorophyll Index, CIg, and the Visible Atmospherically Resistant Vegetation Index, VARI) to foliar anthocyanins in five different species. For comparison purposes the widely used Normalized Difference Vegetation Index, NDVI was also evaluated. Among the four indices tested, the VARI, which uses only spectral bands in the visible region of the electromagnetic spectrum, was found to be inversely and linearly related to the relative amount of foliar anthocyanins. While this result was obtained at leaf level, it opens new possibilities for analyzing anthocyanin content across multiple scales, by means of currently operational aircraft- and spacecraft-mounted broad-band sensor systems. Further studies that evaluate the sensitivity of the VARI to the relative content of anthocyanins across space (e.g., at canopy and regional scales) and time, and its relationship with plant biodiversity and vegetation stresses, are needed.

  5. Natural foliar variegation without costs? The case of Begonia

    PubMed Central

    Sheue, Chiou-Rong; Pao, Shang-Horng; Chien, Lee-Feng; Chesson, Peter; Peng, Ching-I

    2012-01-01

    Background and Aims Foliar variegation is recognized as arising from two major mechanisms: leaf structure and pigment-related variegation. Begonia has species with a variety of natural foliar variegation patterns, providing diverse examples of this phenomenon. The aims of this work are to elucidate the mechanisms underlying different foliar variegation patterns in Begonia and to determine their physiological consequences. Methods Six species and one cultivar of Begonia were investigated. Light and electron microscopy revealed the leaf structure and ultrastructure of chloroplasts in green and light areas of variegated leaves. Maximum quantum yields of photosystem II were measured by chlorophyll fluorescence. Comparison with a cultivar of Ficus revealed key features distinguishing variegation mechanisms. Key Results Intercellular space above the chlorenchyma is the mechanism of variegation in these Begonia. This intercellular space can be located (a) below the adaxial epidermis or (b) below the adaxial water storage tissue (the first report for any taxa), creating light areas on a leaf. In addition, chlorenchyma cell shape and chloroplast distribution within chlorenchyma cells differ between light and green areas. Chloroplasts from both areas showed dense stacking of grana and stroma thylakoid membranes. The maximum quantum yield did not differ significantly between these areas, suggesting minimal loss of function with variegation. However, the absence of chloroplasts in light areas of leaves in the Ficus cultivar led to an extremely low quantum yield. Conclusions Variegation in these Begonia is structural, where light areas are created by internal reflection between air spaces and cells in a leaf. Two forms of air space structural variegation occur, distinguished by the location of the air spaces. Both forms may have a common origin in development where dermal tissue becomes loosely connected to mesophyll. Photosynthetic functioning is retained in light areas, and these areas do not include primary veins, potentially limiting the costs of variegation. PMID:22362664

  6. Wood and foliar respiration of tropical wet forest environment

    NASA Astrophysics Data System (ADS)

    Asao, S.; Bedoya Arrieta, R.; Ryan, M. G.

    2011-12-01

    Wood and foliar respiration from tropical forests constitute major components of ecosystem respiration that may control their productivity and carbon storage. However, few estimates on tropical forests vary greatly. Furthermore, the trees in these forests respire great amounts of carbon, but impacts of individual tree species on respiration is not well known. We examined wood and foliar respiration in this environment in relation to individual tree species. The objectives of this study were to: 1) identify how respiration rates relate to scaling variables for wood and foliage, 2) examine the effects of individual tree species on these relationships, 3) extrapolate the rates to the annual fluxes of the whole stands, and 4) determine if tree species differed in these fluxes. Established on an abandoned pasture in 1988 at La Selva Biological Station in Costa Rica, the monodominant stands contained four native species in a complete randomized block design. Respiration rates based on tissue surface area ranged among dominant tree species from 0.6 to 1.0 ?g C m^-2 s^-1 for small diameter wood (<10cm), 1.0 to 1.8 ?g C m^-2 s^-1 for large diameter wood, and 0.7 to 0.8 ?g C m^-2 s^-1 for foliage. Understory species had similar wood respiration rates, but foliage respiration rates were about half of those for canopy leaves. Among surface area, volume, or biomass, respiration rates scaled best with surface area for wood with small diameter, volume or biomass for large diameter wood, and leaf area for foliage. These relationships differed slightly among tree species and between canopy trees and understory species. Foliar respiration rate was generally related to leaf nitrogen content, and this relationship differed among dominant tree species. Temperature response of foliar respiration also differed among tree species and canopy class. However, daily and annual temperature fluctuations had less than 3% effect on annual flux. Annual respiratory fluxes from wood and foliage averaged 11 Mg C hectare^-1. The difference between species with highest and lowest fluxes was about 3 Mg C hectare^-1, with the highest coming from species with the most amount of biomass and the lowest coming from species with the least biomass. Wood and foliage respiratory fluxes of the whole stand partitioned to canopy foliage ranged from a third to a little less than half, while the flux partitioned to dominant tree wood differed very little from about half. Our results suggest strong abiotic control of wood and foliage respiratory fluxes in this environment, while species affect the fluxes through differences in biomass.

  7. Effectiveness of a calcium sodium phosphosilicate containing prophylaxis paste in reducing dentine hypersensitivity immediately and 4 weeks after a single application: a double-blind randomized controlled trial

    PubMed Central

    Neuhaus, Klaus W; Milleman, Jeffery L; Milleman, Kimberly R; Mongiello, Kimberly A; Simonton, Thomas C; Clark, Courtney E; Proskin, Howard M; Seemann, Rainer

    2013-01-01

    Aims The aim of this single-site, randomized, controlled, double-blind, 3-arm parallel study was to determine the effectiveness of a prophylaxis paste containing 15% calcium sodium phosphosilicate (CSPS; NovaMin®) with and without fluoride in reducing dentine hypersensitivity immediately after a single application and 28 days following dental scaling and root planing. Materials & Methods Overall, 151 subjects were enrolled in this study. All subjects received a scaling and root planing procedure followed by a final prophylaxis step using one of three different prophylaxis pastes: Test-A (15% NovaMin® and NaF), Test-B (15% NovaMin®) and a control. Dentine hypersensitivity was assessed by tactile stimulus (Yeaple Probe®) and by air blast (Schiff scale) at baseline, immediately after and 28 days after a prophylaxis procedure. One hundred and forty-nine subjects completed the study. Results Subjects having received the test prophylaxis pastes showed statistically lower (anova, p < 0.05) dentine hypersensitivity compared with the control group immediately after the prophylaxis procedure (Yeaple Probe®: Test-A = 20.9 ± 12.6, Test-B = 22.7 ± 12.9, Control=11.2 ± 3.1; Schiff score: Test-A = 1.1 ± 0.6, Test-B = 1.1 ± 0.6, Control = 2.0 ± 0.7) and after 28 days (Yeaple probe: Test-A = 21.5 ± 11.9, Test-B = 20.6 ± 11.3, Control = 11.8 ± 6.0; Schiff score: Test-A = 1.0 ± 0.6, Test-B = 1.0 ± 0.6, Control = 2.0 ± 0.7). Conclusions In conclusion, the single application of both fluoridated and non-fluoridated prophylaxis pastes containing 15% CSPS (NovaMin®) provided a significant reduction of dentine hypersensitivity up to at least 28 days. PMID:23414245

  8. Improved biocompatibility of poly(lactic-co-glycolic acid) orv and poly-L-lactic acid blended with nanoparticulate amorphous calcium phosphate in vascular stent applications.

    PubMed

    Zheng, Xiaoxin; Wang, Yujue; Lan, Zhiyuan; Lyu, Yongnan; Feng, Gaoke; Zhang, Yipei; Tagusari, Shizu; Kislauskis, Edward; Robich, Michael P; McCarthy, Stephen; Sellke, Frank W; Laham, Roger; Jiang, Xuejun; Gu, Wei Wang; Wu, Tim

    2014-06-01

    Biodegradable polymers used as vascular stent coatings and stent platforms encounter a major challenge: biocompatibility in vivo, which plays an important role in in-stent restenosis (ISR). Co-formulating amorphous calcium phosphate (ACP) into poly(lactic-co-glycolic acid) (PLGA) or poly-L-lactic acid (PLLA) was investigated to address the issue. For stent coating applications, metal stents were coated with polyethylene-co-vinyl acetate/poly-n-butyl methacrylate (PEVA/PBMA), PLGA or PLGA/ACP composites, and implanted into rat aortas for one and three months. Comparing with both PEVA/PBMA and PLGA groups after one month, the results showed that stents coated with PLGA/ACP had significantly reduced restenosis (PLGA/ACP vs. PEVA/PBMA vs. PLGA: 21.24 +/- 2.59% vs. 27.54 +/- 1.19% vs. 32.12 +/- 3.93%, P < 0.05), reduced inflammation (1.25 +/- 0.35 vs. 1.77 +/- 0.38 vs. 2.30 +/- 0.21, P < 0.05) and increased speed of re-endothelialization (1.78 +/- 0.46 vs. 1.17 +/- 0.18 vs. 1.20 +/- 0.18, P < 0.05). After three months, the PLGA/ACP group still displayed lower inflammation score (1.33 +/- 0.33 vs. 2.27 +/- 0.55, P < 0.05) and higher endothelial scores (2.33 +/- 0.33 vs. 1.20 +/- 0.18, P < 0.05) as compared with the PEVA/PBMA group. Moreover, for stent platform applications, PLLA/ACP stent tube significantly reduced the inflammatory cells infiltration in the vessel walls of rabbit iliac arteries relative to their PLLA cohort (NF-kappaB-positive cells: 23.31 +/- 2.33/mm2 vs. 9.34 +/- 1.35/mm2, P < 0.05). No systemic biochemical or pathological evidence of toxicity was found in either PLGA/ACP or PLLA/ACP. The co-formulation of ACP into PLGA and PLLA resulted in improved biocompatibility without systemic toxicity. PMID:24749387

  9. Calcium-induced calcium release in rod photoreceptor terminals boosts synaptic transmission during maintained depolarization

    PubMed Central

    Cadetti, Lucia; Bryson, Eric J.; Ciccone, Cory A.; Rabl, Katalin; Thoreson, Wallace B.

    2008-01-01

    We examined the contribution of calcium-induced calcium release (CICR) to synaptic transmission from rod photoreceptor terminals. Whole-cell recording and confocal calcium imaging experiments were conducted on rods with intact synaptic terminals in a retinal slice preparation from salamander. Low concentrations of ryanodine stimulated calcium increases in rod terminals, consistent with the presence of ryanodine receptors. Application of strong depolarizing steps (?70 to ?10 mV) exceeding 200 ms or longer in duration evoked a wave of calcium that spread across the synaptic terminals of voltage-clamped rods. This secondary calcium increase was blocked by high concentrations of ryanodine, indicating it was due to CICR. Ryanodine (50 ?M) had no significant effect on rod calcium current (Ica) although it slightly diminished rod light-evoked voltage responses. Bath application of 50 ?M ryanodine strongly inhibited light-evoked currents in horizontal cells. Whether applied extracellularly or delivered into the rod cell through the patch pipette, ryanodine (50 ?M) also inhibited excitatory post-synaptic currents (EPSCs) evoked in horizontal cells by depolarizing steps applied to rods. Ryanodine caused a preferential reduction in the later portions of EPSCs evoked by depolarizing steps of 200 ms or longer. These results indicate that CICR enhances calcium increases in rod terminals evoked by sustained depolarization, which in turn acts to boost synaptic exocytosis from rods. PMID:16819987

  10. Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence

    SciTech Connect

    Tian, Shengke; Lu, Lingli; Xie, Ruohan; Zhang, Minzhe; Jernstedt, Judith A.; Hou, Dandi; Ramsier, Cliff; Brown, Patrick H.

    2015-01-21

    Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF) to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO₄ alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant “GroZyme” resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using μ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower.

  11. Foliar and tuber late blight resistance in a Solanum tuberosum potato mapping population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar and tuber resistance to Phytophthora infestans were evaluated in a mapping population (n=94) developed between two Solanum tuberosum breeding lines, NY121 x NY115. Foliar disease severity of the progeny clones was measured by the area under the disease progress curve (AUDPC) in field tests in...

  12. Foliar disease control demonstrations for watermelon: Distant presentation of field trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar diseases are a serious concern of watermelon producers. In Oklahoma, for instance, several distinct foliar fungal diseases can result in complete crop loss when conditions are conducive to disease development. Proper fungicide use can reduce or prevent losses to these diseases. An educatio...

  13. Foliar fungicides on alfalfa: 2012 University extension field trial results from Minnesota and Wisconsin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To answer the increasing number of questions received regarding the use of foliar fungicide on alfalfa, a group of Extension and USDA Agricultural Research Station staff in southeastern Minnesota and Wisconsin worked together to conduct field research trials to examine the benefit of using a foliar ...

  14. Foliar deficiencies of mature southern Appalachian red spruce determined from fertilizer trials

    SciTech Connect

    Joslin, J.D.; Wolfe, M.H.

    1994-09-01

    A field fertilization study employing additions of Ca, Mg, and N to a mature red spruce (Picea rubens Sarg.) stand was conducted at a high-elevation site in southwestern Virginia. Statistically significant increases in needle weight (20% larger than controls) were observed after two growing seasons in treatments receiving Ca or Ca plus Mg. Significant foliar growth responses were accompanied by significant increases (20-60%) in foliar concentrations of Ca, Zn, Mg, and Mn in current-year and 1-yr-old needles. Both Ca and Mg addition, alone or together, appear to have alleviated antagonisms by Al towards the uptake of these four cations. Both the foliar growth response (negative) and the foliar N concentration response to N addition were nonsignificant, a response consistent with evidence for N saturation at this site. Vector analysis, correlation analyses, and literature evidence all provide support at this site for a foliar deficiency of Zn at a foliar concentration of 14 mg kg{sup -1} and for a foliar and/or root deficiency of Ca at a current-year needle concentration of 1700 mg kg{sup -1}, Foliar concentrations of Ca and Zn at or below these thresholds are common in southern Appalachian red spruce and may be related to its apparent growth decline in the higher elevations. 47 refs., 7 figs., 1 tab.

  15. Segregation of progeny of Solanum tuberosum subsp. andigena for foliar and tuber resistance to late blight.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breeding solely for foliar resistance to late blight without emphasis on tuber resistance has the potential to exacerbate tuber infection. Wild potato species are valuable sources of foliar and tuber blight resistance. However, most species are difficult to sexually hybridize with cultivated potat...

  16. Scaling uncertainties in estimating canopy foliar maintenance respiration for black spruce ecosystems in Alaska

    USGS Publications Warehouse

    Zhang, X.; McGuire, A.D.; Ruess, R.W.

    2006-01-01

    A major challenge confronting the scientific community is to understand both patterns of and controls over spatial and temporal variability of carbon exchange between boreal forest ecosystems and the atmosphere. An understanding of the sources of variability of carbon processes at fine scales and how these contribute to uncertainties in estimating carbon fluxes is relevant to representing these processes at coarse scales. To explore some of the challenges and uncertainties in estimating carbon fluxes at fine to coarse scales, we conducted a modeling analysis of canopy foliar maintenance respiration for black spruce ecosystems of Alaska by scaling empirical hourly models of foliar maintenance respiration (Rm) to estimate canopy foliar Rm for individual stands. We used variation in foliar N concentration among stands to develop hourly stand-specific models and then developed an hourly pooled model. An uncertainty analysis identified that the most important parameter affecting estimates of canopy foliar Rm was one that describes R m at 0??C per g N, which explained more than 55% of variance in annual estimates of canopy foliar Rm. The comparison of simulated annual canopy foliar Rm identified significant differences between stand-specific and pooled models for each stand. This result indicates that control over foliar N concentration should be considered in models that estimate canopy foliar Rm of black spruce stands across the landscape. In this study, we also temporally scaled the hourly stand-level models to estimate canopy foliar Rm of black spruce stands using mean monthly temperature data. Comparisons of monthly Rm between the hourly and monthly versions of the models indicated that there was very little difference between the estimates of hourly and monthly models, suggesting that hourly models can be aggregated to use monthly input data with little loss of precision. We conclude that uncertainties in the use of a coarse-scale model for estimating canopy foliar Rm at regional scales depend on uncertainties in representing needle-level respiration and on uncertainties in representing the spatial variability of canopy foliar N across a region. The development of spatial data sets of canopy foliar N represents a major challenge in estimating canopy foliar maintenance respiration at regional scales. ?? Springer 2006.

  17. Drought alters interactions between root and foliar herbivores.

    PubMed

    Tariq, Muhammad; Rossiter, John T; Wright, Denis J; Staley, Joanna T

    2013-08-01

    Drought can alter plant quality and the strength of trophic interactions between herbivore groups, and is likely to increase in occurrence and severity under climate change. We hypothesized that changes in plant chemistry due to root herbivory and drought stress would affect the performance of a generalist and a specialist aphid species feeding on a Brassica plant. High drought stress increased the negative effect of root herbivory on the performance of both aphid species (30% decrease in fecundity and 15% reduction in intrinsic rate of increase). Aphid performance was greatest at moderate drought stress, though the two species differed in which treatment combination maximized performance. Nitrogen concentration was greatest in high and moderately drought-stressed plants without root herbivores and moderately drought-stressed plants under low root herbivore density, and correlated positively with aphid fecundity for both species. Glucosinolate concentrations increased 62% under combined drought stress and root herbivory, and were positively correlated with extended aphid development time. Root herbivory did not influence relative water content and foliar biomass under normal water regimes but they decreased 24 and 63%, respectively, under high drought stress. This study shows that drought can alter the strength of interactions between foliar and root herbivores, and that plant chemistry is key in mediating such interactions. The two aphid species responded in a broadly similar way to root herbivore and drought-stress treatments, which suggests that generalized predictions of the effects of abiotic factors on interactions between above- and below-ground species may be possible. PMID:23292454

  18. The Mauna Loa environmental matrix: foliar and soil nutrients

    USGS Publications Warehouse

    Vitousek, P.M.; Aplet, G.; Turner, D.; Lockwood, J.J.

    1992-01-01

    The accumulation of total carbon, nitrogen, and phosphorus in soils, available soil nutrients, and foliar nutrients in the native dominant Metrosideros polymorpha were determined across a wide elevational range on 9 lava flows on Mauna Loa, Hawai'i. The flows included a young (2800 y) a??a?? (rough surface texture) and pa??hoehoe (smooth) flow on the wet east and dry northwest side of the mountain. Soil element pools and nutrient availability increased with flow age independent of climate. The dry sites accumulated organic matter and nutrients more slowly than comparable wet sites, but relative nutrient availability to plants (as indicated by soil assays and foliar nutrients) was greater in the dry sites. Accumulation of soil organic matter and nutrients occurred most rapidly in lowerelevation sites on the young flows, but the largest accumulations occurred at higher elevations on old flows. The range of sites sampled represents a complete and largely independent matrix of major factors governing ecosystem structure and function. ?? 1992 Springer-Verlag.

  19. Mapping Amazonian Canopy Foliar Traits with Imaging Spectroscopy

    NASA Astrophysics Data System (ADS)

    Asner, G. P.; Martin, R.; Anderson, C. B.; Knapp, D. E.

    2014-12-01

    Spatial and temporal information on plant functional traits is lacking in ecology, which limits our understanding of how plant communities and ecosystems are changing. This problem is acute in remote tropical regions such as in Andean and Amazonian forests, where information on plant functional traits is difficult to ascertain. We used Carnegie Airborne Observatory visible-to-shortwave infrared (VSWIR) imaging spectroscopy with light detection and ranging (LiDAR) to assess the chemical composition of tropical forests along a 3000 m elevation gradient from lowland Amazonia to the Andean treeline. We calibrated and validated the retrieval of 15 canopy foliar chemicals and leaf mass per area (LMA) in 81 one-hectare field plots using a new VSWIR-LiDAR fusion approach. Remotely sensed estimates of elevational changes in forest foliar pigments, nitrogen, phosphorus, water, soluble and total carbon, cellulose and LMA were similar to those derived via laborious field survey and laboratory analysis. This new airborne approach addresses the inherent limitations and sampling biases associated with field-based studies of forest functional traits, particularly in structurally and floristically complex tropical canopies.

  20. An explicitly solvated full atomistic model of the cardiac thin filament and application on the calcium binding affinity effects from familial hypertrophic cardiomyopathy linked mutations

    NASA Astrophysics Data System (ADS)

    Williams, Michael; Schwartz, Steven

    2015-03-01

    The previous version of our cardiac thin filament (CTF) model consisted of the troponin complex (cTn), two coiled-coil dimers of tropomyosin (Tm), and 29 actin units. We now present the newest revision of the model to include explicit solvation. The model was developed to continue our study of genetic mutations in the CTF proteins which are linked to familial hypertrophic cardiomyopathies. Binding of calcium to the cTnC subunit causes subtle conformational changes to propagate through the cTnC to the cTnI subunit which then detaches from actin. Conformational changes propagate through to the cTnT subunit, which allows Tm to move into the open position along actin, leading to muscle contraction. Calcium disassociation allows for the reverse to occur, which results in muscle relaxation. The inclusion of explicit TIP3 water solvation allows for the model to get better individual local solvent to protein interactions; which are important when observing the N-lobe calcium binding pocket of the cTnC. We are able to compare in silica and in vitro experimental results to better understand the physiological effects from mutants, such as the R92L/W and F110V/I of the cTnT, on the calcium binding affinity compared to the wild type.

  1. Fungicide volatilization measurements: inverse modeling, role of vapor pressure, and state of foliar residue.

    PubMed

    Bedos, Carole; Rousseau-Djabri, Marie-France; Loubet, Benjamin; Durand, Brigitte; Flura, Dominique; Briand, Olivier; Barriuso, Enrique

    2010-04-01

    Few data sets of pesticide volatilization from plants at the field scale are available. In this work, we report measurements of fenpropidin and chlorothalonil volatilization on a wheat field using the aerodynamic gradient (AG) method and an inverse dispersion modeling approach (using the FIDES model). Other data necessary to run volatilization models are also reported: measured application dose, crop interception, plant foliage residue, upwind concentrations, and meteorological conditions. The comparison of the AG and inverse modeling methods proved the latter to be reliable and hence suitable for estimating volatilization rates with minimized costs. Different diurnal/nocturnal volatilization patterns were observed: fenpropidin volatilization peaked on the application day and then decreased dramatically, while chlorothalonil volatilization remained fairly stable over a week-long period. Cumulated emissions after 31 h reached 3.5 g ha(-1) and 5 g ha(-1), respectively (0.8% and 0.6% of the theoretical application dose). A larger difference in volatilization rates was expected given differences in vapor pressure, and for fenpropidin, volatilization should have continued given that 80% of the initial amount remained on plant foliage for 6 days. We thus ask if vapor pressure alone can accurately estimate volatilization just after application and then question the state of foliar residue. We identified adsorption, formulation, and extraction techniques as relevant explanations. PMID:20199019

  2. Self-Setting Calcium Orthophosphate Formulations

    PubMed Central

    Dorozhkin, Sergey V.

    2013-01-01

    In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are bioactive and biodegradable grafting bioceramics in the form of a powder and a liquid. After mixing, both phases form pastes, which set and harden forming either a non-stoichiometric calcium deficient hydroxyapatite or brushite. Since both of them are remarkably biocompartible, bioresorbable and osteoconductive, self-setting calcium orthophosphate formulations appear to be promising bioceramics for bone grafting. Furthermore, such formulations possess excellent molding capabilities, easy manipulation and nearly perfect adaptation to the complex shapes of bone defects, followed by gradual bioresorption and new bone formation. In addition, reinforced formulations have been introduced, which might be described as calcium orthophosphate concretes. The discovery of self-setting properties opened up a new era in the medical application of calcium orthophosphates and many commercial trademarks have been introduced as a result. Currently such formulations are widely used as synthetic bone grafts, with several advantages, such as pourability and injectability. Moreover, their low-temperature setting reactions and intrinsic porosity allow loading by drugs, biomolecules and even cells for tissue engineering purposes. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent bioceramics suitable for both dental and bone grafting applications, has been provided. PMID:24956191

  3. Calcium Intake and Bone health

    MedlinePLUS Videos and Cool Tools

    ... Calcium_Intake_100115.html Calcium Intake and Bone health HealthDay News Video - October 2, 2015 To use ... reading health news for healthier living. Related MedlinePlus Health Topics Bone Diseases Calcium Fractures Seniors' Health About ...

  4. Calcium Pyrophosphate Deposition (CPPD)

    MedlinePLUS

    ... out whether calcium pyrophosphate crystals are present. An X-ray of the joint may help detect whether calcium-containing deposits are present in the cartilage. Doctors call this X-ray appearance chondrocalcinosis, which is almost always due to ...

  5. Lead in calcium supplements.

    PubMed Central

    Scelfo, G M; Flegal, A R

    2000-01-01

    Intercalibrated measurements of lead in calcium supplements indicate the importance of rigorous analytical techniques to accurately quantify contaminant exposures in complex matrices. Without such techniques, measurements of lead concentrations in calcium supplements may be either erroneously low, by as much as 50%, or below the detection limit needed for new public health criteria. In this study, we determined the lead content of 136 brands of supplements that were purchased in 1996. The calcium in the products was derived from natural sources (bonemeal, dolomite, or oyster shell) or was synthesized and/or refined (chelated and nonchelated calcium). The dried products were acid digested and analyzed for lead by high resolution-inductively coupled plasma-mass spectrometry. The method's limit of quantitation averaged 0.06 microg/g, with a coefficient of variation of 1.7% and a 90-100% lead recovery of a bonemeal standard reference material. Two-thirds of those calcium supplements failed to meet the 1999 California criteria for acceptable lead levels (1.5 microg/daily dose of calcium) in consumer products. The nonchelated synthesized and/or refined calcium products, specifically antacids and infant formulas, had the lowest lead concentrations, ranging from nondetectable to 2.9 microg Pb/g calcium, and had the largest proportion of brands meeting the new criteria (85% of the antacids and 100% of the infant formulas). Images Figure 1 Figure 2 PMID:10753088

  6. Spectral unmixing techniques for retrieving plant foliar information

    NASA Astrophysics Data System (ADS)

    Themelis, Kostas; Sykioti, Olga; Rontogiannis, Athanasios; Koutroumbas, Konstantinos; Kyparissis, Aris

    2010-05-01

    In this study two novel approaches for supervised and semi-supervised hyperspectral unmixing are applied in the unmixing of CHRIS/PROBA data, in order to monitor seasonal land cover changes - in particular plant foliar coverage. Foliar coverage variations are directly linked to seasonal changes of the ecophysiological status of a plant (i.e. growth status, pigment concentrations, LAI etc). The high potential of using hyperspectral satellite data in monitoring plant biochemical and structural characteristics is important in ecophysiological studies. A reliable and efficient method to extract leaf and/or canopy information from a mixed pixel significantly contributes towards this direction. In this study, the development of two efficient algorithms in spectral unmixing enables the detection and mapping of leaf contribution to the overall pixel spectra and its seasonal variations. For this purpose, leaf spectra measured in the field, simultaneously to satellite acquisitions, are included in the endmember data set. The proposed unmixing techniques are performed on ground reflectances, assuming knowledge of the number and spectral signatures of the objects present in the images. An efficient estimation for their corresponding fractions in the pixels of the image is developed, based on a recently proposed maximum a posteriori probability (MAP) method. By exploiting the constraints naturally imposed to the problem, closed form expressions are derived for the statistical parameters required by the MAP estimator. In the semi-supervised scenario, we assume that a spectral library is given, containing spectral signatures of multiple endmembers. The objective in the latter case, is (a) to determine how many and which endmembers are present in the mixed pixel under study and (b) to use the selected endmembers to estimate the corresponding abundance fractions - especially the abundance of foliar coverage. The approach is based on a properly modified weighted l1-regularized least squares algorithm. The motivation of using the sparsity promoting l1 norm is that in practice, only a small number of the available endmembers are present in each pixel. Based on this observation, a weighted version of the well-known least absolute shrinkage and selection operator (lasso) criterion is utilized, where weights are used for penalizing different coefficients in the l1-regularization scheme. To efficiently solve the l1 minimization problem, the Least Angle Regression (LARS) algorithm is used. The performance of the proposed methods is compared to the performance of existing unmixing algorithms, such as standard convex programming procedures and ENVI software unmixing routines.

  7. Lasting effects of glutamate on nuclear calcium concentration in cultured rat hippocampal neurons: regulation by calcium stores.

    PubMed Central

    Korkotian, E; Segal, M

    1996-01-01

    1. Changes in free intracellular calcium concentrations ([Ca2+]i) were measured in the nucleus and perinuclear regions of cultured rat hippocampal neurons using either fura-2 or fluo-3 calcium indicators. 2. Brief application of glutamate caused a transient rise of [Ca2+]i in all cell compartments, which recovered to pre-drug levels in all but the nuclear region. The new, higher level of nuclear calcium ([Ca2+]n) was sustained for as long as the cell was monitored. 3. The new level of [Ca2+]n was dependent on the magnitude of the calcium transient, and was higher in older cells in culture, but it did not affect responses to subsequent applications of glutamate. 4. The sustained elevation of [Ca2+]n was prevented by drugs which affect calcium stores (caffeine, ryanodine and Ruthenium Red), indicating that an extranuclear calcium store interacts with [Ca2+]n. Images Figure 1 Figure 8 PMID:8910194

  8. Volatile compounds and sensory attributes of wine from cv. Merlot (Vitis vinifera L.) grown under differential levels of water deficit with or without a kaolin-based, foliar reflectant particle film

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influences on wine volatile composition and wine sensory attributes from a foliar application of a kaolin-based particle film on vines under differing levels of water deficit were evaluated over three consecutive seasons for the cultivar Merlot grown in the high desert region of southwestern Ida...

  9. Foliar uptake of nitrogen oxides: A nitrogen source for forests

    SciTech Connect

    Hanson, P.J.; Taylor, G.E. Jr.; Gunderson, C.A. )

    1989-04-01

    Non-urban concentrations of nitrogen oxide gases are insufficient to directly impede plant growth processes, but foliar uptake of these gases may represent a significant N source. Measurements of NO{sub 2} and HNO{sub 3} vapor uptake by elements representative of a forest landscape (e.g. foliage, bark, forest floor) were conducted in an open gas exchange system. Under daylight conditions using a mean NO{sub 2} level of 33 ml l{sup {minus}1}, NO{sub 2} uptake by foliage of forest tree species ranged from 0.35 to 5.75 nmol m{sup {minus}2} s{sup {minus}1}. Uptake of NO{sub 2} by broadleaf species was greater than by conifers. Dry bark surfaces showed about half the conductance to NO{sub 2} than did plant shoots. Forest floor samples had a disproportionately high conductance to NO{sub 2} when compared to bark or foliage surfaces. At similar concentrations, uptake of HNO{sub 3} vapor exceeded that for NO{sub 2}. Foliar NO{sub 2} uptake, under stomatal control, was principally to leaf interiors, but HNO{sub 3} uptake occurred to leaf interiors and surfaces. Based on ambient NO{sub 2} concentrations and conductance data scaled to the forest canopy, NO{sub 2} deposition provides from 0.1 to 2.0 kg ha{sup {minus}1} y{sup {minus}1} of nitrogen to natural forests (0.1 to 3% of annual needs). Conversely, deposition to urban forests may supply >10% of a forest's annual need.

  10. Relationship between photosynthetic phosphorus-use efficiency and foliar phosphorus fractions in tropical tree species.

    PubMed

    Hidaka, Amane; Kitayama, Kanehiro

    2013-12-01

    How plants develop adaptive strategies to efficiently use nutrients on infertile soils is an important topic in plant ecology. It has been suggested that, with decreasing phosphorus (P) availability, plants increase photosynthetic P-use efficiency (PPUE) (i.e., the ratio of instantaneous photosynthetic carbon assimilation rate per unit foliar P). However, the mechanism to increase PPUE remains unclear. In this study, we tested whether high PPUE is explained by an optimized allocation of P in cells among P-containing biochemical compounds (i.e., foliar P fractions). We investigated the relationships among mass-based photosynthetic carbon assimilation rate (A mass), PPUE, total foliar P concentration, and foliar P fractions in 10 tree species in two tropical montane rain forests with differing soil P availability (five species on sedimentary soils and five species on P-poorer ultrabasic serpentine soils) on Mount Kinabalu, Borneo. We chemically fractionated foliar P into the following four fractions: metabolic P, lipid P, nucleic acid P, and residual P. A mass was positively correlated with the concentrations of total foliar P and of metabolic P across 10 tree species. Mean A mass and mean concentrations of total foliar P and of each foliar P fraction were lower on the P-poorer ultrabasic serpentine soils than on the sedimentary soils. There was a negative relationship between the proportion of metabolic P per total P and the proportion of lipid P per total P. PPUE was positively correlated with the ratio of metabolic P to lipid P. High PPUE is explained by the net effect of a relatively greater investment of P into P-containing metabolites and a relatively lesser investment into phospholipids in addition to generally reduced concentrations of all P fractions. We conclude that plants optimize the allocation of P among foliar P fractions for maintaining their productivity and growth and for reducing demand for P as their adaptation to P-poor soils. PMID:24455122

  11. Relationship between photosynthetic phosphorus-use efficiency and foliar phosphorus fractions in tropical tree species

    PubMed Central

    Hidaka, Amane; Kitayama, Kanehiro

    2013-01-01

    How plants develop adaptive strategies to efficiently use nutrients on infertile soils is an important topic in plant ecology. It has been suggested that, with decreasing phosphorus (P) availability, plants increase photosynthetic P-use efficiency (PPUE) (i.e., the ratio of instantaneous photosynthetic carbon assimilation rate per unit foliar P). However, the mechanism to increase PPUE remains unclear. In this study, we tested whether high PPUE is explained by an optimized allocation of P in cells among P-containing biochemical compounds (i.e., foliar P fractions). We investigated the relationships among mass-based photosynthetic carbon assimilation rate (Amass), PPUE, total foliar P concentration, and foliar P fractions in 10 tree species in two tropical montane rain forests with differing soil P availability (five species on sedimentary soils and five species on P-poorer ultrabasic serpentine soils) on Mount Kinabalu, Borneo. We chemically fractionated foliar P into the following four fractions: metabolic P, lipid P, nucleic acid P, and residual P. Amass was positively correlated with the concentrations of total foliar P and of metabolic P across 10 tree species. Mean Amass and mean concentrations of total foliar P and of each foliar P fraction were lower on the P-poorer ultrabasic serpentine soils than on the sedimentary soils. There was a negative relationship between the proportion of metabolic P per total P and the proportion of lipid P per total P. PPUE was positively correlated with the ratio of metabolic P to lipid P. High PPUE is explained by the net effect of a relatively greater investment of P into P-containing metabolites and a relatively lesser investment into phospholipids in addition to generally reduced concentrations of all P fractions. We conclude that plants optimize the allocation of P among foliar P fractions for maintaining their productivity and growth and for reducing demand for P as their adaptation to P-poor soils. PMID:24455122

  12. Calcium addition at the Hubbard Brook Experimental Forest increases sugar storage, antioxidant activity and cold tolerance in native red spruce (Picea rubens).

    PubMed

    Halman, Joshua M; Schaberg, Paul G; Hawley, Gary J; Eagar, Christopher

    2008-06-01

    In fall (November 2005) and winter (February 2006), we collected current-year foliage of native red spruce (Picea rubens Sarg.) growing in a reference watershed and in a watershed treated in 1999 with wollastonite (CaSiO(3), a slow-release calcium source) to simulate preindustrial soil calcium concentrations (Ca-addition watershed) at the Hubbard Brook Experimental Forest (Thornton, NH). We analyzed nutrition, soluble sugar concentrations, ascorbate peroxidase (APX) activity and cold tolerance, to evaluate the basis of recent (2003) differences between watersheds in red spruce foliar winter injury. Foliar Ca and total sugar concentrations were significantly higher in trees in the Ca-addition watershed than in trees in the reference watershed during both fall (P=0.037 and 0.035, respectively) and winter (P=0.055 and 0.036, respectively). The Ca-addition treatment significantly increased foliar fructose and glucose concentrations in November (P=0.013 and 0.007, respectively) and foliar sucrose concentrations in winter (P=0.040). Foliar APX activity was similar in trees in both watersheds during fall (P=0.28), but higher in trees in the Ca-addition watershed during winter (P=0.063). Cold tolerance of foliage was significantly greater in trees in the Ca-addition watershed than in trees in the reference watershed (P<0.001). Our results suggest that low foliar sugar concentrations and APX activity, and reduced cold tolerance in trees in the reference watershed contributed to their high vulnerability to winter injury in 2003. Because the reference watershed reflects forest conditions in the region, the consequences of impaired physiological function caused by soil Ca depletion may have widespread implications for forest health. PMID:18381266

  13. [Calcium and health].

    PubMed

    Ortega Anta, Rosa M; Jimnez Ortega, Ana I; Lpez-Sobaler, Ana M

    2015-01-01

    An adequate intake of calcium is only not limited to avoid the risk of osteoporosis and its benefits in longterm bone health, but also it has been linked to protection against various major diseases, such as hypertension, cancer, kidney stones, insulin resistance, diabetes... and several investigations suggest its importance in preventing and controlling obesity. Studies conducted in Spanish representative samples show that a high percentage of adults and children (> 75%) don't achieve the recommended intake of calcium. Moreover, are growing trends among the population suggesting that calcium intake and dairy consumption (main food source of the mineral) are high, and even excessive, in many individuals. This misconception results in that the calcium intake is increasingly far from the recommended one. The maximum tolerable intake of the mineral is fixed at 2.500 mg/day, but this intake is unusual, and it's more disturbing and frequent, to find intakes below the recommended calcium intakes (1.000 and 1.200 mg/day in adults, men and women, respectively). Data from different studies highlight the risk of an inadequate calcium intake and the damages that may affect the health in a long term. It is not about transmitting indiscriminate guidelines in order to increase the intake of calcium / dairy, but the recommended intakes must be met to achieve both the nutritional and health benefits. Also activities for demystification of misconceptions are need, increasingly frequent, that may impair health population. PMID:25862324

  14. CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING ON LEFT, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING ON LEFT, CALCIUM CHLORIDE STORAGE BUILDING ON RIGHT OF CENTER WITH TOP OF SA (SODA ASH) BUILDING IN RIGHT BACKGROUND. - Solvay Process Company, Calcium Chloride Plant, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  15. Calcium, cola, calamity.

    PubMed

    Hintz, H F

    1980-01-01

    It appears that, in spite of many critics, the intake of soft drinks will continue to increase and that of milk will continue to decrease. The soft drinks contain no nutrients other than sugar, whereas milk contains many nutrients. Thus, the substitution of soft drinks for milk results in great decreases of minerals, protein, and vitamins but calcium is a nutrient of particular concern because milk is the major source of calcium. Therefore, the trend towards substituting soft drinks for milk should be reversed in order to ensure adequate intake of calcium and better nutrition. PMID:6991213

  16. Gastrointestinal absorption of calcium from milk and calcium salts.

    PubMed

    Sheikh, M S; Santa Ana, C A; Nicar, M J; Schiller, L R; Fordtran, J S

    1987-08-27

    Whether ingested calcium is absorbed more efficiently from freely water-soluble calcium salts than from poorly soluble salts is unclear. It is also unknown whether calcium is absorbed better from dairy products than from calcium salts. Using a method by which the net absorption of calcium can be accurately measured after a single dose, we studied eight healthy fasting subjects after they took a 500-mg dose of calcium from each of five calcium salts with various degrees of water solubility and from milk. The order of administration of the agents given was randomly determined. The mean (+/- SEM) net calcium absorption, in decreasing order of the solubility of the salts, was 32 +/- 4 percent from calcium acetate, 32 +/- 4 percent from calcium lactate, 27 +/- 3 percent from calcium gluconate, 30 +/- 3 percent from calcium citrate, and 39 +/- 3 percent from calcium carbonate. The differences in absorption were not statistically significant according to analysis of variance. On the basis of in vitro solubility experiments in acid mediums, we hypothesize that acid dissolution in the gastrointestinal tract may be responsible for the similar absorption of calcium from salts with widely different water solubilities. Calcium absorption from whole milk (31 +/- 3 percent) was similar to absorption from calcium salts. We conclude that calcium absorption from carbonate, acetate, lactate, gluconate, and citrate salts of calcium, and from whole milk, is similar in fasting healthy young subjects. Further study will be required to determine whether the results would be different in older subjects, with a higher dose of calcium, or if the calcium was ingested with food. PMID:3614304

  17. EFFECT OF CHELATED CALCIUM ON VALENCIA PEANUT YIELD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium nutrition is often a yield limiting factor for peanuts and is necessary for pod growth and increased peg strength. Calcium (Ca) applied to the fruiting zone increases the number of pods per plant. Application of Ca 30 to 45 days after penetration of gynophores into the soil increased the p...

  18. EVALUATION OF CALCIUM SENSORS IN FRESH AND SALTWATER

    EPA Science Inventory

    The Orion Calcium Ion Electrode No. 93-20 was evaluated for suitability as a calcium ion sensor for monitoring or in-situ marine applications by testing for the following parameters: accuracy, precision, temperature dependence, short- and long-term stability, durability, sensitiv...

  19. Calcium Imaging Perspectives in Plants

    PubMed Central

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Occhipinti, Andrea; Maffei, Massimo E.

    2014-01-01

    The calcium ion (Ca2+) is a versatile intracellular messenger. It provides dynamic regulation of a vast array of gene transcriptions, protein kinases, transcription factors and other complex downstream signaling cascades. For the past six decades, intracellular Ca2+ concentration has been significantly studied and still many studies are under way. Our understanding of Ca2+ signaling and the corresponding physiological phenomenon is growing exponentially. Here we focus on the improvements made in the development of probes used for Ca2+ imaging and expanding the application of Ca2+ imaging in plant science research. PMID:24599077

  20. Stoichiometry of Calcium Medicines

    ERIC Educational Resources Information Center

    Pinto, Gabriel

    2005-01-01

    The topic of calcium supplement and its effects on human lives is presented in the way of questions to the students. It enables the students to realize the relevance of chemistry outside the classroom surrounding.

  1. High Blood Calcium (Hypercalcemia)

    MedlinePLUS

    ... mineral found mostly in your bones, where it builds and maintains bone strength. A small amount of calcium is also ... Imaging studies also may be helpful, such as bone mineral density, ultrasound, or other types of scans. How is high ...

  2. Foliar Spray with Vermiwash Modifies the Arbuscular Mycorrhizal Dependency and Nutrient Stoichiometry of Bhut Jolokia (Capsicum assamicum)

    PubMed Central

    Gupta, Rajeev; Veer, Vijay; Singh, Lokendra; Kalita, Mohan C.

    2014-01-01

    Vermiwash (VW), a liquid extract obtained from vermicomposting beds, is used as an organic fertilizer for crop plants. The current study investigated the effect of a vermiwash foliar spray on the response of bhut jolokia (Capsicum assamicum) exposed to two different arbuscular mycorrhizal fungi (AMF: Rhizophagus irregularis, RI and G. mosseae, GM) in acidic soil under naturally ventilated greenhouse conditions. The VW spray significantly influenced the growth of plants receiving the dual treatment of AMF+VW. Plant growth was more prominent in the GM+VW treatment group than that in the RI+VW treatment group. The plant-AMF interactions in relation to growth and nutrient requirements were also significantly influenced by the application of VW. Interestingly, the VW treatment appeared to contribute more N to plants when compared to that under the AMF treatment, which led to changes in the C:N:P stoichiometry in plant shoots. Furthermore, the increased potassium dependency, as observed in the case of the dual treatments, suggests the significance of such treatments for improving crop conditions under salt stress. Overall, our study shows that the VW foliar spray modifies the response of a crop to inoculations of different AMF with regard to growth and nutrient utilization, which has implications for the selection of an efficient combination of nutrient source for improving crop growth. PMID:24651577

  3. Foliar spray with vermiwash modifies the Arbuscular mycorrhizal dependency and nutrient stoichiometry of Bhut Jolokia (Capsicum assamicum).

    PubMed

    Khan, Mohammad Haneef; Meghvansi, Mukesh K; Gupta, Rajeev; Veer, Vijay; Singh, Lokendra; Kalita, Mohan C

    2014-01-01

    Vermiwash (VW), a liquid extract obtained from vermicomposting beds, is used as an organic fertilizer for crop plants. The current study investigated the effect of a vermiwash foliar spray on the response of bhut jolokia (Capsicum assamicum) exposed to two different arbuscular mycorrhizal fungi (AMF: Rhizophagus irregularis, RI and G. mosseae, GM) in acidic soil under naturally ventilated greenhouse conditions. The VW spray significantly influenced the growth of plants receiving the dual treatment of AMF+VW. Plant growth was more prominent in the GM+VW treatment group than that in the RI+VW treatment group. The plant-AMF interactions in relation to growth and nutrient requirements were also significantly influenced by the application of VW. Interestingly, the VW treatment appeared to contribute more N to plants when compared to that under the AMF treatment, which led to changes in the C:N:P stoichiometry in plant shoots. Furthermore, the increased potassium dependency, as observed in the case of the dual treatments, suggests the significance of such treatments for improving crop conditions under salt stress. Overall, our study shows that the VW foliar spray modifies the response of a crop to inoculations of different AMF with regard to growth and nutrient utilization, which has implications for the selection of an efficient combination of nutrient source for improving crop growth. PMID:24651577

  4. Toxicity of seven foliar insecticides to four insect parasitoids attacking citrus and cotton pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laboratory studies were carried out to compare the relative toxicity of seven foliar insecticides against four species of beneficial insects representing two families of HYmenoptera: Aphelinidae (Aphytis melinus Debach, Eretmocerus eremicus Rose & Zolnerowich, and Encarsia formosa Gahan) and MYmarid...

  5. Application of laser ablation multicollector inductively coupled plasma mass spectrometry for the measurement of calcium and lead isotope ratios in packaging for discriminatory purposes.

    PubMed

    Santamaria-Fernandez, Rebeca; Wolff, Jean-Claude

    2010-07-30

    The potential of high-precision calcium and lead isotope ratio measurements using laser ablation coupled to multicollector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) to aid distinction between four genuine and five counterfeit pharmaceutical packaging samples and further classification of counterfeit packaging samples has been evaluated. We highlight the lack of reference materials for LA-MC-ICP-MS isotope ratio measurements in solids. In this case the problem is minimised by using National Institute of Standards and Technology Standard Reference Material (NIST SRM) 915a calcium carbonate (as solid pellets) and NIST SRM610 glass disc for sample bracketing external standardisation. In addition, a new reference material, NIST SRM915b calcium carbonate, has been characterised in-house for Ca isotope ratios and is used as a reference sample. Significant differences have been found between genuine and counterfeit samples; the method allows detection of counterfeits and aids further classification of packaging samples. Typical expanded uncertainties for measured-corrected Ca isotope ratio values ((43)Ca/(44)Ca and (42)Ca/(44)Ca) were found to be below 0.06% (k = 2, 95% confidence) and below 0.2% for measured-corrected Pb isotope ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb). This is the first time that Ca isotope ratios have been measured in packaging materials using LA coupled to a multicollector (MC)-ICP-MS instrument. The use of LA-MC-ICP-MS for direct measurement of Ca and Pb isotopic variations in cardboard/ink in packaging has definitive potential to aid counterfeit detection and classification. PMID:20552700

  6. Field evaluation of in situ remediation of Cd-contaminated soil using four additives, two foliar fertilisers and two varieties of pakchoi.

    PubMed

    Feng, Renwei; Qiu, Weiwen; Lian, Fei; Yu, Zhihong; Yang, YiXin; Song, Zhengguo

    2013-07-30

    This study was conducted to determine the optimal planting mode for pakchoi (Brassica rapa chinensis) in Cd-contaminated soil to reduce the accumulation of Cd in the edible parts while maintaining yields. Four additives (red mud (RM), silicon calcium fertiliser (SC), spodium (SP) and calcium magnesium phosphate (CMP)), two foliar fertilisers (Ca and Zn) and two varieties of pakchoi (Aijiaohuang (AJ) and Baixuegongzhu (BX)) were used in this study. The results show that the addition of SC and RM had an effect, but the other additives did not appear to increase the biomasses of AJ and BX. In some cases, the growth responses of AJ and BX to the same treatment were different. Extra additions of Ca or Zn to additive-treated pakchoi did not help the additives stimulate the growth of AJ and BX, except for SC-treated AJ and BX and SP-treated AJ. The SC and CMP additives significantly reduced the available Cd concentration in both the AJ soil and the BX soil; however, they did not significantly decrease the Cd concentration in the aboveground parts of AJ and BX. The RM treatments (for both levels) and some treatments containing SP reduced the available Cd concentration in the soils and reduced the accumulation of Cd in the two pakchoi varieties. Additions of Ca or Zn fertiliser significantly reduced the Cd concentration in the aboveground parts of AJ and BX. However, when Ca or Zn was sprayed on the additive-treated AJ and BX, they did not help the additives reduce the Cd accumulation in the aboveground parts of AJ and BX, except for the additive CMP. This study shows that RM may be an optimal amendment to reduce the accumulation of Cd in the edible part of pakchoi while simultaneously maintaining yields. The utilisation of Ca or Zn as a foliar fertiliser to additive-treated pakchoi showed positive effects only under some conditions. PMID:23603772

  7. Exploring the remote sensing of foliar biochemical concentrations with AVIRIS data

    NASA Technical Reports Server (NTRS)

    Smith, Geoffrey M.; Curran, Paul J.

    1992-01-01

    Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data shows promise for the estimation of foliar biochemical concentrations at the scale of the canopy. There are, however, several problems associated with the use of AVIRIS data in this way and these are detailed in recent Plant Biochemical Workshop Report. The research reported was concentrated upon three of these problems: field sampling of forest canopies, wet laboratory assay of foliar chemicals, and the visualization of AVIRIS data.

  8. Calcium-41 concentration in terrestrial materials: prospects for dating of pleistocene samples

    SciTech Connect

    Henning, W.; Bell, W.A.; Billquist, P.J.; Glagola, B.G.; Kutschera, W.; Liu, Z.; Lucas, H.F.; Paul, M.; Rehm, K.E.; Yntema, J.L.

    1987-05-08

    Calcium-41 bas been suggested as a new tool for radiometric dating in the range of 10/sup 5/ to 10/sup 6/ years. The concentration of cosmogenic calcium-41 in natural samples of terrestrial origin has now been determined by high-sensitivity accelerator mass spectrometry after pre-enrichment in calcium-41 with an isotope separator. Ratios of calcium-41 to total calcium between 2 x 10/sup -14/ and 3 x 10/sup -15/ were measured for samples of contemporary bovine bone and from limestone deposits. Some prospects for the use of calcium-41 for dating Middle and Late Pleistocene bone and for other geophysical applications are discussed.

  9. Fluid fragmentation shapes rain-induced foliar disease transmission

    PubMed Central

    Gilet, T.; Bourouiba, L.

    2015-01-01

    Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between rainfalls and plant disease outbreaks were reported; however, the detailed mechanisms linking the two were relegated to a black box. In this combined experimental and theoretical study, we focus on the impact dynamics of raindrops on infected leaves, one drop at a time. We find that the deposition range of most of the pathogen-bearing droplets is constrained by a hydrodynamical condition and we quantify the effect of leaf size and compliance on such constraint. Moreover, we identify and characterize two dominant fluid fragmentation scenarios as responsible for the dispersal of most pathogen-bearing droplets emitted from infected leaves: (i) the crescent-moon ejection is driven by the direct interaction between the impacting raindrop and the contaminated sessile drop and (ii) the inertial detachment is driven by the motion imparted to the leaf by the raindrop, leading to catapult-like droplet ejections. We find that at first, decreasing leaf size or increasing compliance reduces the range of pathogen-bearing droplets and the subsequent epidemic onset efficiency. However, this conclusion only applies for the crescent moon ejection. Above a certain compliance threshold a more effective mechanism of contaminated fluid ejection, the inertial detachment, emerges. This compliance threshold is determined by the ratio between the leaf velocity and the characteristic velocity of fluid fragmentation. The inertial detachment mechanism enhances the range of deposition of the larger contaminated droplets and suggests a change in epidemic onset pattern and a more efficient potential of infection of neighbouring plants. Dimensionless parameters and scaling laws are provided to rationalize our observations. Our results link for the first time the mechanical properties of foliage with the onset dynamics of foliar epidemics through the lens of fluid fragmentation. We discuss how the reported findings can inform the design of mitigation strategies acting at the early stage of a foliar disease outbreak. PMID:25652459

  10. Fluid fragmentation shapes rain-induced foliar disease transmission.

    PubMed

    Gilet, T; Bourouiba, L

    2015-03-01

    Plant diseases represent a growing threat to the global food supply. The factors contributing to pathogen transmission from plant to plant remain poorly understood. Statistical correlations between rainfalls and plant disease outbreaks were reported; however, the detailed mechanisms linking the two were relegated to a black box. In this combined experimental and theoretical study, we focus on the impact dynamics of raindrops on infected leaves, one drop at a time. We find that the deposition range of most of the pathogen-bearing droplets is constrained by a hydrodynamical condition and we quantify the effect of leaf size and compliance on such constraint. Moreover, we identify and characterize two dominant fluid fragmentation scenarios as responsible for the dispersal of most pathogen-bearing droplets emitted from infected leaves: (i) the crescent-moon ejection is driven by the direct interaction between the impacting raindrop and the contaminated sessile drop and (ii) the inertial detachment is driven by the motion imparted to the leaf by the raindrop, leading to catapult-like droplet ejections. We find that at first, decreasing leaf size or increasing compliance reduces the range of pathogen-bearing droplets and the subsequent epidemic onset efficiency. However, this conclusion only applies for the crescent moon ejection. Above a certain compliance threshold a more effective mechanism of contaminated fluid ejection, the inertial detachment, emerges. This compliance threshold is determined by the ratio between the leaf velocity and the characteristic velocity of fluid fragmentation. The inertial detachment mechanism enhances the range of deposition of the larger contaminated droplets and suggests a change in epidemic onset pattern and a more efficient potential of infection of neighbouring plants. Dimensionless parameters and scaling laws are provided to rationalize our observations. Our results link for the first time the mechanical properties of foliage with the onset dynamics of foliar epidemics through the lens of fluid fragmentation. We discuss how the reported findings can inform the design of mitigation strategies acting at the early stage of a foliar disease outbreak. PMID:25652459

  11. Foliar Water Uptake of Tamarix ramosissima from an Atmosphere of High Humidity

    PubMed Central

    Li, Shuang; Xiao, Hong-lang; Zhao, Liang; Zhou, Mao-Xian; Wang, Fang

    2014-01-01

    Many species have been found to be capable of foliar water uptake, but little research has focused on this in desert plants. Tamarix ramosissima was investigated to determine whether its leaves can directly absorb water from high humidity atmosphere and, if they can, to understand the magnitude and importance of foliar water uptake. Various techniques were adopted to demonstrate foliar water uptake under submergence or high atmospheric humidity. The mean increase in leaf water content after submergence was 29.38% and 20.93% for mature and tender leaves, respectively. In the chamber experiment, obvious reverse sap flow occurred when relative humidity (RH) was persistently above 90%. Reverse flow was recorded first in twigs, then in branches and stems. For the stem, the percentage of negative sap flow rate accounting for the maximum value of sap flow reached 10.71%, and its amount accounted for 7.54% of diurnal sap flow. Small rainfall can not only compensate water loss of plant by foliar uptake, but also suppress transpiration. Foliar uptake can appear in the daytime under certain rainfall events. High atmospheric humidity is beneficial for enhancing the water status of plants. Foliar uptake should be an important strategy of water acquisition for desert plants. PMID:24982964

  12. 21 CFR 201.70 - Calcium labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... diet”. The warnings in §§ 201.64(c), 201.70(c), 201.71(c), and 201.72(c) may be combined, if applicable, provided the ingredients are listed in alphabetical order, e.g., a calcium or sodium restricted diet. 1...

  13. Soil and foliar nutrient and nitrogen isotope composition (?(15)N) at 5 years after poultry litter and green waste biochar amendment in a macadamia orchard.

    PubMed

    Bai, Shahla Hosseini; Xu, Cheng-Yuan; Xu, Zhihong; Blumfield, Timothy J; Zhao, Haitao; Wallace, Helen; Reverchon, Frdrique; Van Zwieten, Lukas

    2015-03-01

    This study aimed to evaluate the improvement in soil fertility and plant nutrient use in a macadamia orchard following biochar application. The main objectives of this study were to assess the effects of poultry litter and green waste biochar applications on nitrogen (N) cycling using N isotope composition (?(15)N) and nutrient availability in a soil-plant system at a macadamia orchard, 5 years following application. Biochar was applied at 10 t ha(-1) dry weight but concentrated within a 3-m diameter zone when trees were planted in 2007. Soil and leaf samples were collected in 2012, and both soil and foliar N isotope composition (?(15)N) and nutrient concentrations were assessed. Both soil and foliar ?(15)N increased significantly in the poultry litter biochar plots compared to the green waste biochar and control plots. A significant relationship was observed between soil and plant ?(15)N. There was no influence of either biochars on foliar total N concentrations or soil NH4 (+)-N and NO3 (-)-N, which suggested that biochar application did not pose any restriction for plant N uptake. Plant bioavailable phosphorus (P) was significantly higher in the poultry litter biochar treatment compared to the green waste biochar treatment and control. We hypothesised that the bioavailability of N and P content of poultry litter biochar may play an important role in increasing soil and plant ?(15)N and P concentrations. Biochar application affected soil-plant N cycling and there is potential to use soil and plant ?(15)N to investigate N cycling in a soil-biochar-tree crop system. The poultry litter biochar significantly increased soil fertility compared to the green waste biochar at 5 years following biochar application which makes the poultry litter a better feedstock to produce biochar compared to green waste for the tree crops. PMID:25266060

  14. Chitosan-coated mesoporous microspheres of calcium silicate hydrate: environmentally friendly synthesis and application as a highly efficient adsorbent for heavy metal ions.

    PubMed

    Zhao, Jing; Zhu, Ying-Jie; Wu, Jin; Zheng, Jian-Qiang; Zhao, Xin-Yu; Lu, Bing-Qiang; Chen, Feng

    2014-03-15

    Chitosan-coated calcium silicate hydrate (CSH/chitosan) mesoporous microspheres formed by self-assembly of nanosheets have been synthesized in aqueous solution under ambient conditions without using any toxic surfactant or organic solvent. The method reported herein has advantages of simplicity, low cost and being environmentally friendly. The BET specific surface area of CSH/chitosan mesoporous microspheres is measured to be as high as ~356 m(2) g(-1), which is considerably high among calcium silicate materials. The as-prepared CSH/chitosan mesoporous microspheres are promising adsorbent and exhibit a quick and highly efficient adsorption behavior toward heavy metal ions of Ni(2+), Zn(2+), Cr(3+), Pb(2+) Cu(2+) and Cd(2+) in aqueous solution. The adsorption kinetics can be well fitted by the pseudo second-order model. The maximum adsorption amounts of Ni(2+), Zn(2+), Pb(2+), Cu(2+) and Cd(2+) on CSH/chitosan mesoporous microspheres are extremely high, which are 406.6, 400, 796, 425 and 578 mg/g, respectively. The CSH/chitosan adsorbent exhibits the highest affinity for Pb(2+) ions among five heavy metal ions. The adsorption capacities of the CSH/chitosan adsorbent toward heavy metal ions are relatively high compared with those reported in the literature. PMID:24461837

  15. Application of the Molecular Interaction Volume Model (MIVM) to Calcium-Based Liquid Alloys of Systems Forming High-Melting Intermetallics

    SciTech Connect

    Poizeau, S; Sadoway, DR

    2013-06-05

    The thermodynamic properties of multiple liquid alloys with strong negative deviation from ideality were successfully modeled by the molecular interaction volume model (MIVM). The modeled partial Gibbs free energy of calcium in Ca-Ag, Ca-In, Ca-Pb, Ca-Sn, Ca-Tl, and Ca-Zn at 800 degrees C was within 1.5 kJ/mol of the existing experimental data. The partial Gibbs free energy of calcium in Ca-Bi liquid alloys at 600 degrees C was predicted within 1.6 kJ/mol (or 1%) by the MIVM from experimental data at 800 degrees C. For the first time, the MIVM was applied to a ternary system far from ideality, Ca-Sb-Pb. The partial Gibbs free energy of Ca in six Ca-Pb-Sb alloys was determined by emf measurements in a cell configured as Ca(s)vertical bar CaF2(s)vertical bar Ca-Sb-Pb, over the temperature range of 500-830 degrees C. These values were 2% (or 5 kJ/mol) more negative than those predicted by the MIVM using experimental data for the Ca-Pb, Ca-Sb, and Pb-Sb binary alloys. This difference was attributed to the inability of the MIVM to account for interactions between the first nearest neighbors of Ca, Pb and Sb in the ternary Ca-Sb-Pb alloy.

  16. Foliar Uptake of Atmospheric Reactive Nitrogen Pollution Along an Urban-Rural Gradient in New York State

    NASA Astrophysics Data System (ADS)

    Vallano, D.; Sparks, J. P.

    2008-12-01

    Vegetation is an important sink for atmospheric reactive nitrogen (N) pollution in terrestrial ecosystems, and when soil N is limiting, foliar N uptake can be a source of plant-available N. A proxy for pollution derived N, and in particular foliar assimilated N, would be useful to quantify the impact of the foliar uptake pathway on plant metabolism. Nitrogen stable isotope ratios (15N/14N) are practical for this purpose because forms of plant-available N often have varying isotopic compositions. However, the mechanisms driving differences in foliar N isotopic composition (?15N) are still unresolved. Current understanding of foliar ? 15N suggests these values primarily represent the integration of the soil water solution ?15N, direct foliar uptake of atmospheric reactive N, within-plant fractionations, and fractionation due to the fungus to root transfer in mycorrhizae. In this study, we investigated the influence of direct foliar uptake, soil solution ? 15N, and mycorrhizae on foliar ?15N in seedlings of two dominant Northeastern tree species, red maple (Acer rubrum) and red oak (Quercus rubra), along an N deposition gradient in New York State. Using a potted plant mesocosm system, we compared foliar ?15N values directly to soil solution ?15N values while controlling for mycorrhizal associations. Both species showed higher foliar ?15N when exposed to fractionation by mycorrhizal associations. Overall, A. rubrum showed higher foliar ?15N than Q. rubra across all sites. In both species, patterns of foliar ?15N values were coupled with soil solution ?15N values across the N deposition gradient. Additionally, increasing atmospheric N deposition was correlated with higher foliar ?15N values in Q. rubra, but not in A. rubrum. Using a mixing model, we estimated that Q. rubra seedlings incorporated up to 7% of their assimilated N via direct foliar uptake of atmospheric N pollution. However, foliar uptake was not detectable in A. rubrum seedlings. Results suggest that the use of foliar ?15N values may be an effective tool to estimate the magnitude of foliar uptake of pollutant N compounds under some circumstances.

  17. Stoichiometric patterns in foliar nutrient resorption across multiple scales.

    PubMed

    Reed, Sasha C; Townsend, Alan R; Davidson, Eric A; Cleveland, Cory C

    2012-10-01

    Nutrient resorption is a fundamental process through which plants withdraw nutrients from leaves before abscission. Nutrient resorption patterns have the potential to reflect gradients in plant nutrient limitation and to affect a suite of terrestrial ecosystem functions. Here, we used a stoichiometric approach to assess patterns in foliar resorption at a variety of scales, specifically exploring how N : P resorption ratios relate to presumed variation in N and/or P limitation and possible relationships between N : P resorption ratios and soil nutrient availability. N : P resorption ratios varied significantly at the global scale, increasing with latitude and decreasing with mean annual temperature and precipitation. In general, tropical sites (absolute latitudes < 2326') had N : P resorption ratios of < 1, and plants growing on highly weathered tropical soils maintained the lowest N : P resorption ratios. Resorption ratios also varied with forest age along an Amazonian forest regeneration chronosequence and among species in a diverse Costa Rican rain forest. These results suggest that variations in N : P resorption stoichiometry offer insight into nutrient cycling and limitation at a variety of spatial scales, complementing other metrics of plant nutrient biogeochemistry. The extent to which the stoichiometric flexibility of resorption will help regulate terrestrial responses to global change merits further investigation. PMID:22882279

  18. Characterization of polyketide metabolites from foliar endophytes of Picea glauca.

    PubMed

    Sumarah, Mark W; Puniani, Eva; Blackwell, Barbara A; Miller, J David

    2008-08-01

    A collection of 250 foliar endophytes of Picea glauca (white spruce) yielded several isolates that produced metabolites toxic to Choristoneura fumiferana (spruce budworm). Three of these strains were selected for further study based on their ability to be cultured and produce secondary metabolites under laboratory conditions. The culture filtrate of each was extracted and analyzed by LC-MS and LC-NMR, and the major metabolites were isolated and characterized. Structures were elucidated by spectroscopic analyses including 2D NMR and HRMS and by comparison to literature data. In some cases the extract was methylated in order to facilitate separation, but the original natural structure was determined by comparing the NMR data of the isolated methylated product with that of the stop-flow NMR of the underivatized extract (i.e., 2a, 2b, and 4). Two of these metabolites, 1 and 2a, are new structures, 3 and 4 are reported here for the first time as fungal metabolites, and 5- 10 as known fungal metabolites from other species. Tyrosol (10) was the only common metabolite found in all three extracts but did not account for the observed toxicity to C. fumiferana. PMID:18636777

  19. Plant homeostasis of foliar manganese sinks: specific variation in hyperaccumulators.

    PubMed

    Fernando, Denise R; Woodrow, Ian E; Baker, Alan J M; Marshall, Alan T

    2012-11-01

    Plant manganese (Mn) hyperaccumulation provides unusual insight into homeostasis of this essential micronutrient, in particular its excessive storage in shoot tissues. The compartmentation of hyperaccumulated foliar Mn appears exceptional among metal hyperaccumulators, since it occurs via specific microdistribution patterns. Here, three associated Mn hyperaccumulators, Virotia neurophylla, Maytenus fournieri, and Garcinia amplexicaulis exhibiting distinctly different Mn detoxification strategies were examined. Non-invasive sample preparation in conjunction with cryo scanning electron microscopy (SEM) was used to obtain in vivo quantitative microprobe X-ray and anatomical data from fully hydrated cells. Highly vacuolated large palisade mesophyll cells in V. neurophylla leaves were found to contain around 650mM Mn. The large non-photosynthetic hypodermal cells of M. fournieri leaves, also with high vacuolar content, and the main site for Mn disposal, had an estimated mean vacuolar Mn concentration of around 600mM. Previous qualitative X-ray mapping had shown Mn to be almost evenly sequestered across the entire leaf cross section of G. amplexicaulis. However, quantitative data obtained here showed a marked variation in localised concentrations that ranged between~15 and>800mM. Notable among these were mean values of>600mM in spongy mesophyll cells, and~800mM within cells of a narrow sub epidermal layer preceding the palisade mesophyll. This study demonstrated the extraordinary Mn carrying capacities of different types of leaf cell vacuoles. PMID:22772585

  20. The effect of signal noise on the remote sensing of Foliar biochemical concentration

    NASA Technical Reports Server (NTRS)

    Smith, Geoffrey M.; Curran, Paul J.

    1993-01-01

    Spectral measurements made using an imaging spectrometer contain systematic and random noise, while the former can be corrected the latter remains a source of error in the remotely sensed signal. A number of investigators have tried to determine the signal-to-noise-ratio (SNR) of the instrument, or the resultant imagery. However, the level of noise at which spectra are too noisy to be useful is not usually determined. The first attempt was by Goetz and Calvin, who suggested that the depth of the absorption feature should be at least an order of magnitude greater than the noise and more recently Dekker suggested a SNR of around 600:1 was required in visible/near infrared wavelengths to measure a 1/gl change in chlorophyll a concentration water. The wide range of applications of imaging spectroscopy make it difficult to set SNR specifications as they are dependent on a number of factors, one of the most important being reflectance of a particular target. For example, the SNR of imagery for vegetated targets is relatively low simply because vegetation has a relatively low level of reflectance. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) is being used to estimate the concentration of biochemicals within vegetation canopies. This paper reports a study undertaken to identify first, wavebands that were highly correlated with foliar biochemical concentration and second, to determine how sensitive these correlations were to sensor noise.

  1. [Aortic calcification and calcium].

    PubMed

    Tsushima, Motoo

    2010-11-01

    Vascular calcification occurred as the last step of arteriosclerosis makes a lot of disturbances on vascular function and should influence on the worsening of the vascular diseases. Calcium is the main component of the vascular calcification like bone, and one of causes of vascular calcification should be the hypoparathyroidism due to the lowering of serum calcium and the following calcium paradox seen in osteoporosis. Bone calcium must shift to the arterial wall from the bone. Medial calcification could be formed under the molecular regulatory control like in bone by differentiated osteoblast or chondroblast from pericyte like cell origin smooth muscle cell. Many substances such as osteopontine, osteocalcine, bone morphogenetic protein 2, matrix Gla protein and alkaliphosphatase were found in calcified area. In intimal calcification, degenerated elastin and macrophage originated calcification were found. In the process of degeneration of elastin polypentapeptide structure in elastin can be easily conbined to Ca(2+), elastin-Ca(2+) complex is neutralized by PO4(2-) and calcium phosphate is accumulated in degenerated elastin. PMID:21037382

  2. Calcium - Multiple Languages: MedlinePlus

    MedlinePLUS

    ... Calcium English ?? - ???? (Chinese - Simplified) PDF Chinese Community Health Resource Center Chinese - Traditional (????) Calcium English ?? - ???? (Chinese - Traditional) PDF Chinese Community Health Resource Center Calcium and Vitamin D: Important at ...

  3. Inositol trisphosphate and calcium signalling

    NASA Astrophysics Data System (ADS)

    Berridge, Michael J.

    1993-01-01

    Inositol trisphosphate is a second messenger that controls many cellular processes by generating internal calcium signals. It operates through receptors whose molecular and physiological properties closely resemble the calcium-mobilizing ryanodine receptors of muscle. This family of intracellular calcium channels displays the regenerative process of calcium-induced calcium release responsible for the complex spatiotemporal patterns of calcium waves and oscillations. Such a dynamic signalling pathway controls many cellular processes, including fertilization, cell growth, transformation, secretion, smooth muscle contraction, sensory perception and neuronal signalling.

  4. Circadian Models of Serum Potassium, Sodium, and Calcium Concentrations in Healthy Individuals and Their Application to Cardiac Electrophysiology Simulations at Individual Level

    PubMed Central

    Fijorek, Kamil; Puskulluoglu, Miroslawa

    2013-01-01

    In the article a brief description of the biological basis of the regulation of human biological clocks was presented in order to introduce the role of circadian rhythms in physiology and specifically in the pharmacological translational tools based on the computational physiology models to motivate the need to provide models of circadian fluctuation in plasma cations. The main aim of the study was to develop statistical models of the circadian rhythm of potassium, sodium, and calcium concentrations in plasma. The developed ion models were further tested by assessing their influence on QT duration (cardiac endpoint) as simulated by the biophysically detailed models of human left ventricular cardiomyocyte. The main results are model equations along with an electronic supplement to the article that contains a fully functional implementation of all models. PMID:24078832

  5. Application of calcium chloride as an additive for secondary refrigerant in the air conditioning system type chiller to minimized energy consumption

    NASA Astrophysics Data System (ADS)

    Suwono, A.; Indartono, Y. S.; Irsyad, M.; Al-Afkar, I. C.

    2015-09-01

    One way to resolve the energy problem is to increase the efficiency of energy use. Air conditioning system is one of the equipment that needs to be considered, because it is the biggest energy user in commercial building sector. Research currently developing is the use of phase change materials (PCM) as thermal energy storage (TES) in the air conditioning system to reduce energy consumption. Salt hydrates have been great potential to be developed because they have been high latent heat and thermal conductivity. This study has used a salt hydrate from calcium chloride to be tested in air conditioning systems type chiller. Thermal characteristics were examined using temperature history (T-history) test and differential scanning calorimetry (DSC). The test results showed that the thermal characteristics of the salt hydrate has been a high latent heat and in accordance with the evaporator temperature. The use of salt hydrates in air conditioning system type chiller can reduce energy consumption by 51.5%.

  6. Portable fluorescence photometer for monitoring free calcium

    NASA Astrophysics Data System (ADS)

    Struckmeier, Jens; Klopp, Erk; Born, Matthias; Hofmann, Martin; Tenbosch, Jochen; Jones, David B.

    2000-12-01

    We introduce a compact and portable photometric system for measurements of the calcium dynamics in cells. The photometer is designed for applications in centrifuges or in zero gravity environment and thus extremely compact and reliable. It operates with the calcium-sensitive dye Indo-1. The excitation wavelength of 345 nm is generated by frequency doubling of a laser diode. Two compact photomultiplier tubes detect the fluorescent emission. The electronics provide the sensitivity of photon counting combined with simultaneous measurement of the temperature, of air pressure, and of gravitational force. Internal data storage during the experiment is possible. A newly developed cell chamber stabilizes the cell temperature to 37.00.1 C and includes a perfusion system to supply the cells with medium. The system has a modular setup providing the possibility of changing the light source and detectors for investigation of ions other than calcium. Measurements of the intracellular calcium concentration are based on a comprehensive calibration of our system. First experiments show that the calcium dynamics of osteosarcoma cells stimulated by parathyroid hormone is observable.

  7. Ultrathin calcium silicate hydrate nanosheets with large specific surface areas: synthesis, crystallization, layered self-assembly and applications as excellent adsorbents for drug, protein, and metal ions.

    PubMed

    Wu, Jin; Zhu, Ying-Jie; Chen, Feng

    2013-09-01

    A simple and low-cost solution synthesis is reported for low-crystalline 1.4 nm tobermorite-like calcium silicate hydrate (CSH) ultrathin nanosheets with a thickness of ~2.8 nm and with a large specific surface area (SSA), via a reaction-rate-controlled precipitation process. The BET SSA of the CSH ultrathin nanosheets can reach as high as 505 m(2) g(-1) . The CSH ultrathin nanosheets have little cytotoxicity and can be converted to anhydrous calcium silicate (ACS) ultrathin nanosheets with a well preserved morphology via a heat treatment process. The crystallinity of CSH ultrathin nanosheets can be improved by solvothermal treatment in water/ethanol binary solvents or a single solvent of water, producing well-crystalline 1.1 nm tobermorite-like CSH nanobelts or nanosheets. CSH ultrathin nanosheets acting as building blocks can self-assemble into layered nanostructures via three different routes. The CSH ultrathin nanosheets are investigated as promising adsorbents for protein (hemoglobin, Hb), drug (ibuprofen, IBU), and metal ions (Cr(3+) , Ni(2+) , Cu(2+) , Zn(2+) , Cd(2+) , Pb(2+) ). The highest adsorbed percentages of Hb and IBU are found to be 83% and 94%, respectively. The highest adsorption capacities of Hb and IBU are found to be as high as 878 milligram Hb per gram CSH and 2.2 gram IBU per gram CSH, respectively. The ppm level metal ions can be totally adsorbed from aqueous solution in just a few minutes. Thus, the CSH ultrathin nanosheets are a promising candidate as excellent adsorbents in the biomedical field and for waste water treatment. Several empirical laws are summarized based on the adsorption profiles of Hb and IBU using CSH ultrathin nanosheets as the adsorbent. Furthermore, the ACS ultrathin nanosheets as adsorbents for Hb protein and IBU drug are investigated. PMID:23585365

  8. Preparation and characterization of porous calcium titanate-based coated glass fiber filter material and its application in determination of lead and cadmium ion concentrations in water.

    PubMed

    Zhang, Dong; Yu, Ping; He, Xiang

    2011-01-01

    Glass fiber filter coated with a porous block adsorption agent of calcium titanate (GPCTO) was prepared by the citric acid sol-gel method, and characterized by X-ray diffraction, scanning electron microscopy, and FTIR spectrophotometry. Its Pb2+ and Cd2+ adsorption properties from water were studied. Adsorption and elution were investigated under different conditions, as were the thermodynamics and kinetics of adsorption, using Cd ion as representative. Calcium titanate may react with glass fiber, forming Si-O-Ti and B-O-Ti bonds and becoming a composite adsorbent. The Pb and Cd ions were quantitatively retained at pH 4-9; their adsorption capacities by the GPCTO were 199.72 and 19.68 mg/g, respectively. The isothermal data were described by the Langmuir equation. The dynamic data followed the pseudo-second-order kinetic model well. The enthalpy change (AH) of the adsorption process was 37.160 kJ/mol. At various temperatures, Gibbs free energy changes (delta G) were negative, and entropy changes (delta S) were positive. The activation energy (Ea) was 38.127 kJ/mol for the adsorption. Cd ion adsorption by the GPCTO was endothermic and spontaneous. The adsorbed Pb and Cd ions were completely recovered by elution with 2 M HNO3. The Pb+ and Cd2+ concentration factors were up to 200. The method has been applied to the preconcentration for flame atomic absorption spectrometric determinations of trace Pb and Cd ions in water samples. The recoveries were 95.2 to 102.4% for Pb and 92.2 to 98.0% for Cd. PMID:22320102

  9. Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.

    ERIC Educational Resources Information Center

    Henrickson, Charles H.; Robinson, Paul R.

    1979-01-01

    The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)

  10. Size-mediated foliar response to ozone in black cherry trees.

    PubMed

    Fredericksen, T S; Skelly, J M; Steiner, K C; Kolb, T E; Kouterick, K B

    1996-01-01

    Local ozone concentration and visible foliar injury were measured over the 1994 growing season on open-grown black cherry (Prunus serotina Ehrh.) trees of varying size (age) within forest stands and adjacent openings at a site in north-central Pennsylvania. Relationships were determined between visible ozone injury and ozone exposure, as well as calculated between injury and ozone uptake expressed as the product of stomatal conductance and ozone concentration. In addition, simultaneous measurements of visible symptoms and leaf gas exchange were also conducted to determine the correlation between visible and physiological injury and ozone exposure. By September, the amount of leaf area affected by visible foliar ozone injury was greatest for seedlings (46%), followed by canopy trees (20%) and saplings (15%). A large amount of variability in foliar ozone symptom expression was observed among trees within a size class. Sum40 and Sum60 (ozone concentration > 40 and > 60 nl liter(-1)) cumulative exposure statistics were the most meaningful indices for interpretation of foliar injury response. Seedlings were apparently more sensitive to ozone injury than larger trees because their higher rates of stomatal conductance resulted in higher rates of ozone uptake. Seedlings also had higher rates of early leaf abscission than larger trees with an average of nearly 30% of the leaves on a shoot abscised by 1 September compared to approximately 5% for larger trees. However, per unit ozone uptake into the leaf, larger trees exhibited larger amounts of foliar injury. The amount of visible foliar injury was negatively correlated (r(2) = 0.82) with net photosynthetic rates, but was not related to stomatal conductance. Net photosynthesis and stomatal conductance thus became uncoupled at high levels of visible foliar injury. PMID:15091453

  11. Sintering of calcium phosphate bioceramics.

    PubMed

    Champion, E

    2013-04-01

    Calcium phosphate ceramics have become of prime importance for biological applications in the field of bone tissue engineering. This paper reviews the sintering behaviour of these bioceramics. Conventional pressureless sintering of hydroxyapatite, Ca10(PO4)6(OH)2, a reference compound, has been extensively studied. Its physico-chemistry is detailed. It can be seen as a competition between two thermally activated phenomena that proceed by solid-state diffusion of matter: densification and grain growth. Usually, the objective is to promote the first and prevent the second. Literature data are analysed from sintering maps (i.e. grain growth vs. densification). Sintering trajectories of hydroxyapatite produced by conventional pressureless sintering and non-conventional techniques, including two-step sintering, liquid phase sintering, hot pressing, hot isostatic pressing, ultrahigh pressure, microwave and spark plasma sintering, are presented. Whatever the sintering technique may be, grain growth occurs mainly during the last step of sintering, when the relative bulk density reaches 95% of the maximum value. Though often considered very advantageous, most assisted sintering techniques do not appear very superior to conventional pressureless sintering. Sintering of tricalcium phosphate or biphasic calcium phosphates is also discussed. The chemical composition of calcium phosphate influences the behaviour. Similarly, ionic substitutions in hydroxyapatite or in tricalcium phosphate create lattice defects that modify the sintering rate. Depending on their nature, they can either accelerate or slow down the sintering rate. The thermal stability of compounds at the sintering temperature must also be taken into account. Controlled atmospheres may be required to prevent thermal decomposition, and flash sintering techniques, which allow consolidation at low temperature, can be helpful. PMID:23212081

  12. Calcium metabolism in microgravity.

    PubMed

    Heer, M; Kamps, N; Biener, C; Korr, C; Boerger, A; Zittermann, A; Stehle, P; Drummer, C

    1999-09-01

    Unloading of weight bearing bones as induced by microgravity or immobilization has significant impacts on the calcium and bone metabolism and is the most likely cause for space osteoporosis. During a 4.5 to 6 month stay in space most of the astronauts develop a reduction in bone mineral density in spine, femoral neck, trochanter, and pelvis of 1%-1.6% measured by Dual Energy X-ray Absorption (DEXA). Dependent on the mission length and the individual turnover rates of the astronauts it can even reach individual losses of up to 14% in the femoral neck. Osteoporosis itself is defined as the deterioration of bone tissue leading to enhanced bone fragility and to a consequent increase in fracture risk. Thinking of long-term missions to Mars or interplanetary missions for years, space osteoporosis is one of the major concerns for manned spaceflight. However, decrease in bone density can be initiated differently. It either can be caused by increases in bone formation and bone resorption resulting in a net bone loss, as obtained in fast looser postmenopausal osteoporosis. On the other hand decrease in bone formation and increase in bone resorption also leads to bone losses as obtained in slow looser postmenopausal osteoporosis or in Anorexia Nervosa patients. Biomarkers of bone turnover measured during several missions indicated that the pattern of space osteoporosis is very similar to the pattern of Anorexia Nervosa patients or slow looser postmenopausal osteoporosis. However, beside unloading, other risk factors for space osteoporosis exist such as stress, nutrition, fluid shifts, dehydration and bone perfusion. Especially nutritional factors may contribute considerably to the development of osteoporosis. From earthbound studies it is known that calcium supplementation in women and men can prevent bone loss of 1% bone per year. Based on these results we studied the calcium intake during several European missions and performed an experiment during the German MIR 97 mission where we investigated the effects of high calcium intake (>1000 mg/d) and vitamin D supplementation (650 IU/d) on the calcium and bone metabolism during 21 days in microgravity. In the MIR 97 mission high calcium intake and vitamin D supplementation led to high ionized calcium levels and a marked decrease in calcitriol levels together with decreased bone formation and increased bone resorption markers. Our conclusion from the MIR 97 mission is that an adequate calcium intake and vitamin D supplementation during space missions is mandatory but, in contrast to terrestrial conditions, does not efficiently counteract the development of space osteoporosis. PMID:10477499

  13. Intestinal Stem Cells: Got Calcium?

    PubMed

    Nszai, Mt; Cordero, Julia B

    2016-02-01

    Calcium ions are well-known intracellular signalling molecules. A new study identifies local cytoplasmic calcium as a central integrator of metabolic and proliferative signals in Drosophila intestinal stem cells. PMID:26859268

  14. Calcium carbonate with magnesium overdose

    MedlinePLUS

    The combination of calcium carbonate and magnesium is commonly found in antacids, which are medicines that provide heartburn relief. Calcium carbonate with magnesium overdose occurs when someone accidentally or ...

  15. Precision and accuracy of visual foliar injury assessments

    SciTech Connect

    Gumpertz, M.L.; Tingey, D.T.; Hogsett, W.E.

    1982-07-01

    The study compared three measures of foliar injury: (i) mean percent leaf area injured of all leaves on the plant, (ii) mean percent leaf area injured of the three most injured leaves, and (iii) the proportion of injured leaves to total number of leaves. For the first measure, the variation caused by reader biases and day-to-day variations were compared with the innate plant-to-plant variation. Bean (Phaseolus vulgaris 'Pinto'), pea (Pisum sativum 'Little Marvel'), radish (Rhaphanus sativus 'Cherry Belle'), and spinach (Spinacia oleracea 'Northland') plants were exposed to either 3 ..mu..L L/sup -1/ SO/sub 2/ or 0.3 ..mu..L L/sup -1/ ozone for 2 h. Three leaf readers visually assessed the percent injury on every leaf of each plant while a fourth reader used a transparent grid to make an unbiased assessment for each plant. The mean leaf area injured of the three most injured leaves was highly correlated with all leaves on the plant only if the three most injured leaves were <100% injured. The proportion of leaves injured was not highly correlated with percent leaf area injured of all leaves on the plant for any species in this study. The largest source of variation in visual assessments was plant-to-plant variation, which ranged from 44 to 97% of the total variance, followed by variation among readers (0-32% of the variance). Except for radish exposed to ozone, the day-to-day variation accounted for <18% of the total. Reader bias in assessment of ozone injury was significant but could be adjusted for each reader by a simple linear regression (R/sup 2/ = 0.89-0.91) of the visual assessments against the grid assessments.

  16. Calcium and Vitamin D

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adequate intakes of vitamin D and calcium are essential preventative measures and essential components of any therapeutic regimen for osteoporosis. Vitamin D is also important for the prevention of falls. Current evidence suggests that a 25-hydroxyvitamin D level of 75 nmol/L (30 ng/ml) or higher ...

  17. Calcium biofortification of crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    More than half of the world's population is deficient in calcium (Ca), iron (Fe), iodine (I), magnesium (Mg), selenium (Se), or zinc (Zn). The consumption of plants, directly or via livestock, containing inadequate concentrations of particular minerals causes these deficiencies. Agronomic and geneti...

  18. Calcium silicate insulation structure

    DOEpatents

    Kollie, Thomas G.; Lauf, Robert J.

    1995-01-01

    An insulative structure including a powder-filled evacuated casing utilizes a quantity of finely divided synthetic calcium silicate having a relatively high surface area. The resultant structure-provides superior thermal insulating characteristics over a broad temperature range and is particularly well-suited as a panel for a refrigerator or freezer or the insulative barrier for a cooler or a insulated bottle.

  19. Ozone air pollution and foliar injury development on native plants of Switzerland.

    PubMed

    Novak, Kristopher; Skelly, John M; Schaub, Marcus; Kruchi, Norbert; Hug, Christian; Landolt, Werner; Bleuler, Peter

    2003-01-01

    The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber research facility located within the Lattecaldo Cantonal Forest Nursery in Canton Ticino, southern Switzerland (600 m asl). Plants were examined daily and dates of initial foliar injury were recorded in order to determine the cumulative AOT40 ppb h ozone exposure required to cause visible foliar injury. Plant responses to ozone varied significantly among species; 11 species exhibited visible symptoms typical of exposures to ambient ozone. The symptomatic species (from most to least sensitive) were Populus nigra, Viburnum lantana, Salix alba, Crataegus monogyna, Viburnum opulus, Tilia platyphyllos, Cornus alba, Prunus avium, Fraxinus excelsior, Ribes alpinum, and Tilia cordata; Clematis spp. did not show foliar symptoms. Of the 11 symptomatic species, five showed initial injury below the critical level AOT40 10 ppmh O3 in the 2001 season. PMID:12804826

  20. Identification of Genes in Thuja plicata Foliar Terpenoid Defenses1[C][W][OA

    PubMed Central

    Foster, Adam J.; Hall, Dawn E.; Mortimer, Leanne; Abercromby, Shelley; Gries, Regine; Gries, Gerhard; Bohlmann, Jörg; Russell, John; Mattsson, Jim

    2013-01-01

    Thuja plicata (western redcedar) is a long-lived conifer species whose foliage is rarely affected by disease or insect pests, but can be severely damaged by ungulate browsing. Deterrence to browsing correlates with high foliar levels of terpenoids, in particular the monoterpenoid α-thujone. Here, we set out to identify genes whose products may be involved in the production of α-thujone and other terpenoids in this species. First, we generated a foliar transcriptome database from which to draw candidate genes. Second, we mapped the storage of thujones and other terpenoids to foliar glands. Third, we used global expression profiling to identify more than 600 genes that are expressed at high levels in foliage with glands, but can either not be detected or are expressed at low levels in a natural variant lacking foliar glands. Fourth, we used in situ RNA hybridization to map the expression of a putative monoterpene synthase to the epithelium of glands and used enzyme assays with recombinant protein of the same gene to show that it produces sabinene, the monoterpene precursor of α-thujone. Finally, we identified candidate genes with predicted enzymatic functions for the conversion of sabinene to α-thujone. Taken together, this approach generated both general resources and detailed functional characterization in the identification of genes of foliar terpenoid biosynthesis in T. plicata. PMID:23388118

  1. Impregnating Coal With Calcium Carbonate

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.; Voecks, Gerald E.; Gavalas, George R.

    1991-01-01

    Relatively inexpensive process proposed for impregnating coal with calcium carbonate to increase rates of gasification and combustion of coal and to reduce emission of sulfur by trapping sulfur in calcium sulfide. Process involves aqueous-phase reactions between carbon dioxide (contained within pore network of coal) and calcium acetate. Coal impregnated with CO2 by exposing it to CO2 at high pressure.

  2. The Plasma Membrane Calcium Pump

    NASA Technical Reports Server (NTRS)

    Rasmussen, H.

    1983-01-01

    Three aspect of cellular calcium metabolism in animal cells was discussed including the importance of the plasma membrane in calcium homeostasis, experiments dealing with the actual mechanism of the calcium pump, and the function of the pump in relationship to the mitochondria and to the function of calmodulin in the intact cell.

  3. Calcium Supplements and Kidney Health

    MedlinePLUS Videos and Cool Tools

    ... Calcium_Supplements_101415.html Calcium Supplements and Kidney Health HealthDay News Video - October 15, 2015 To use ... health news that matters to you. Related MedlinePlus Health Topics Calcium Dietary Supplements Kidney Stones About MedlinePlus ...

  4. Cytoplasmic calcium fluctuations in calcium overloaded Xenopus laevis oocytes.

    PubMed

    Poledna, J; Packová, V

    1995-08-01

    Cytoplasmic calcium fluctuations were studied in calcium overloaded Xenopus oocytes. Calcium sensitive chloride currents were recorded using the two-electrode voltage clamp technique. Fluctuations of chloride currents measured under the voltage clamp were elicited by injection of calcium into the cytoplasm. Contrary to infrequent injections of small calcium amounts which evoke smooth transient responses, the fluctuating chloride currents are due to overloading of intracellular calcium stores which then release calcium repeatedly. Chloride current fluctuations in calcium overloaded oocytes can be reversibly suppressed by caffeine. This effect is concentration dependent, and the amplitude decrease of fluctuations is already apparent at 2 mmol/l caffeine. Power spectra density of fluctuations have been analyzed; they exhibited this pronounced effect of caffeine. Other effective inhibitors were tetracaine and heparin. The results of the present work suggest that at least a part of the endoplasmic reticulum in Xenopus oocytes is a calcium releasing calcium store which can be activated by calcium at the resting inositol trisphosphate concentration. PMID:8720697

  5. Root zone calcium modulates the response of potato plants to heat stress.

    PubMed

    Kleinhenz, Matthew D; Palta, Jiwan P

    2002-05-01

    Potato plant growth and development are known to be severely impacted by heat stress. Here plants grown in a chemically inert medium of 1 : 1 quartzite : perlite (v : v) were subjected to either 35/25 degrees C (stress) or 20/15 degrees C (control) day/night air temperatures and four concentrations of root zone calcium (5, 25, 125 and 600 &mgr;M Ca) for 3 weeks. We report for the first time that potato plant growth under heat stress can persist at specific levels of Ca2+ in the root zone and that the Ca2+ level required for growth under heat stress exceeds that required for growth under normal temperatures. We also provide strong, initial evidence that the ability of high Ca2+ levels to mitigate heat stress effects results from shifts in meristematic activity. Total foliar mass and leaf area were essentially unaffected by Ca2+ level under control temperatures. Under heat stress, leaf area was reduced to about 5% of the control at 5 and 25 &mgr;M Ca but to only 70% of the control at 125 and 600 &mgr;M Ca. Likewise, total foliar mass was reduced under heat stress to about 30% of the control at 5 and 25 &mgr;M Ca but total foliar mass was greater under heat stress than control conditions at 125 and 600 &mgr;M Ca. This increase at higher Ca2+ concentrations was due primarily to axillary shoot growth. Anatomical studies of leaves grown under heat stress show that cell expansion was impaired by heat stress and this impairment was overcome by increasing root zone calcium levels. These results provide insight into the mechanism by which root zone Ca2+ may modulate plant response to heat stress. PMID:12010474

  6. Physicochemical characterization and biocompatibility in vitro of biphasic calcium phosphate/polyvinyl alcohol scaffolds prepared by freeze-drying method for bone tissue engineering applications.

    PubMed

    Nie, Lei; Chen, Dong; Suo, Jinping; Zou, Peng; Feng, Shuibin; Yang, Qi; Yang, Shuhua; Ye, Shunan

    2012-12-01

    In this study, a well developed porous biphasic calcium phosphate (BCP)/polyvinyl alcohol (PVA) scaffold was prepared by emulsion foam freeze-drying method possessed moderate inter-connected pores and porosity. The SEM analysis showed that BCP nano-particles could disperse uniformly in the scaffolds, and the pore size, porosity, and compressive strength could be controlled by the weight ratio of BCP/PVA. The in vitro degradation and cytocompatibility of scaffolds were examined in this study. The degradation analysis showed the prepared scaffolds have a low variation of pH values (approximately 7.18-7.36) in SBF solution, and have the biodegradation rate of BCP/PVA scaffolds decreased with the increase of PVA concentration. Moreover, MTT assay indicated that the BCP/PVA porous scaffold has no negative effects on cells growth and proliferation, and the hBMSCs possessed a favorable spreading morphology on the BCP/PVA scaffold surface. The inter-connected pore structure, mechanical strength, biodegradation rate and cytocompatibility of the prepared BCP/PVA scaffold can meet essential requirements for blame bearing bone tissue engineering and regeneration. PMID:22766294

  7. Application of a simple method using minute particles of amorphous calcium phosphate for recovery of norovirus from cabbage, lettuce, and ham.

    PubMed

    Shinohara, Michiyo; Uchida, Kazue; Shimada, Shin-ichi; Tomioka, Kyoko; Suzuki, Noriko; Minegishi, Toshitaka; Kawahashi, Sachie; Yoshikawa, Yuko; Ohashi, Norio

    2013-01-01

    In this study, the amorphous calcium phosphate (ACP) method developed previously for calicivirus concentration from water was applied for norovirus detection from food. The viral recovery from cabbage, lettuce, or ham (10g of each) was firstly examined in seeding experiments with feline caliciviruses (FCVs). The viruses were concentrated by viral adsorption to ACP particles (0.3g) in the eluent solution (40ml) from foods, collection of the particles by centrifugation, followed by dissolution of the particles with 3.3M citric acid (3ml). In ham, FCV recovery was improved by addition of ascorbic acids into the eluent solution before ACP-particle adsorption. Quantitative real-time reverse transcription-PCR (qRT-PCR) revealed that FCV recoveries were 32-33%, 50-55%, and 37-46% from cabbage, lettuce, and ham, respectively, when seeded with 10(3)-10(4) viruses, and detection limits were estimated ?10(3) genomic copies in all 3 foods. Subsequently, the ACP-concentration method was evaluated for norovirus (NoV) detection from these 3 foods. The recoveries and detection limit of NoVs determined by qRT-PCR were 12-41% and 10(3) (genomic copies) from cabbage, 30-57% and 10(3) from lettuce, and 20-26% and 10(4) from ham, when seeded with 10(3)-10(5) viruses. This simple method may be suitable for NoV detection from these foods. PMID:23046989

  8. Protein ligand-tethered synthetic calcium indicator for localization control and spatiotemporal calcium imaging in plant cells.

    PubMed

    Takaoka, Yousuke; Shigenaga, Miyuki; Imai, Masaki; Nukadzuka, Yuuki; Ishimaru, Yasuhiro; Saito, Kei; Yokoyama, Ryusuke; Nishitani, Kazuhiko; Ueda, Minoru

    2016-01-01

    In plant biology, calcium ions are involved in a variety of intriguing biological phenomena as a secondary messenger. However, most conventional calcium indicators are not applicable for plant cells because of the difficulty with their localization control in plant cells. We here introduce a method to monitor spatiotemporal Ca(2+) dynamics in living plant cells based on linking the synthetic calcium indicator Calcium Green-1 to a natural product-based protein ligand. In a proof-of-concept study using cultured BY-2 cells overexpressing the target protein for the ligand, the ligand-tethered probe accumulated in the cytosol and nucleus, and enabled real-time monitoring of the cytosolic and nucleus Ca(2+) dynamics under the physiological condition. The present strategy using ligand-tethered fluorescent sensors may be successfully applied to reveal the spatiotemporal dynamics of calcium ions in living plant cells. PMID:26602280

  9. Foliar Treatments of 2,4-Dichlorophenoxyacetic Acid for Control of Common Scab in Potato Have Beneficial Effects on Powdery Scab Control

    PubMed Central

    Thompson, Hannah Katherine; Tegg, Robert Stephen; Corkrey, Ross; Wilson, Calum Rae

    2014-01-01

    Prior studies have shown that applications of the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) to the foliage of potato plants can reduce common scab. Here field and glasshouse trials suggest that 2,4-D foliar treatments may also reduce the biologically distinct tuber disease, powdery scab. Significant correlations between suppression of common and powdery scab from the field trials suggested an interaction between the two diseases or possible additional broad spectrum mechanisms of enhanced defence against pathogen invasion provided by 2,4-D treatment. PMID:25009832

  10. Oxidative calcium release from catechol.

    PubMed

    Riley, Patrick A; Stratford, Michael R L

    2015-04-01

    Oxidation of 4-methylcatechol previously exposed to aqueous calcium chloride was shown by ion chromatography to be associated with release of calcium ions. The catechol was oxidised to the corresponding orthoquinone by the use of tyrosinase from Agaricus bisporus. The oxidative release of calcium from the catechol is ascribed to the diminution of the available hydroxyl functions able to act as chelating groups. Our results suggest that the redox status of melanin may regulate calcium binding and influence calcium levels in pigmented cells. PMID:25740160

  11. Voltage-Gated Calcium Channels

    NASA Astrophysics Data System (ADS)

    Zamponi, Gerald Werner

    Voltage Gated Calcium Channels is the first comprehensive book in the calcium channel field, encompassing over thirty years of progress towards our understanding of calcium channel structure, function, regulation, physiology, pharmacology, and genetics. This book balances contributions from many of the leading authorities in the calcium channel field with fresh perspectives from risings stars in the area, taking into account the most recent literature and concepts. This is the only all-encompassing calcium channel book currently available, and is an essential resource for academic researchers at all levels in the areas neuroscience, biophysics, and cardiovascular sciences, as well as to researchers in the drug discovery area.

  12. Purple Phototrophic Bacterium Enhances Stevioside Yield by Stevia rebaudiana Bertoni via Foliar Spray and Rhizosphere Irrigation

    PubMed Central

    Wu, Jing; Wang, Yiming; Lin, Xiangui

    2013-01-01

    This study was conducted to compare the effects of foliar spray and rhizosphere irrigation with purple phototrophic bacteria (PPB) on growth and stevioside (ST) yield of Stevia. rebaudiana. The S. rebaudiana plants were treated by foliar spray, rhizosphere irrigation, and spray plus irrigation with PPB for 10 days, respectively. All treatments enhanced growth of S. rebaudiana, and the foliar method was more efficient than irrigation. Spraying combined with irrigation increased the ST yield plant -1 by 69.2% as compared to the control. The soil dehydrogenase activity, S. rebaudiana shoot biomass, chlorophyll content in new leaves, and soluble sugar in old leaves were affected significantly by S+I treatment, too. The PPB probably works in the rhizosphere by activating the metabolic activity of soil bacteria, and on leaves by excreting phytohormones or enhancing the activity of phyllosphere microorganisms. PMID:23825677

  13. Sulfur to nitrogen ratios in Ponderosa pine as bioindicators of foliar sulfur loading from air pollution

    SciTech Connect

    Johns, C.

    1984-01-01

    The objective of the research was to investigate the potential of foliar S:N ratios in Ponderosa pine as bioindicators of foliar sulfur loading in areas of long-term exposure to low levels of sulfurous air pollutants. First it was necessary to document seasonal variation in S:N ratios in trees not exposed to air pollution. Fifteen Ponderosa pines were selected at a site remote from urban and industrial sources of air pollution and the trees sampled at 18 intervals over a 15 month study period. Significant differences in sulfur and nitrogen concentrations occurred among the five needle age groups within most collections. One-year-old needles contained significantly more sulfur than other needles. Current-year needles contained more nitrogen than the three and four-year-old needles. Within each foliar age class significant differences in total sulfur content and S:N ratios occurred throughout the season. Sulfur concentrations and S:N r

  14. [Correlation analysis between foliar endophytic fungi of Salvia miltiorrhiza and effective components].

    PubMed

    Ding, Xiao-li; Sun, Jian-jun; Liang, Jian; Wang, Na; Cui, Lang-jun

    2015-07-01

    The aim of this study was to comprehensively investigate the correlations between foliar fungal endophyte communities and effective components accumulations in Salvia miltiorrhiza. Foliar samples of S. miltiorrhiza were collected in 5 different areas. Their fungal endophyte communities and effective component contents were determined by denaturing gradient gel electrophoresis (DGGE) and high performance liquid chromatography (HPLC), respectively. The results showed that, for characteristics of foliar fungal endophyte communities and effective component contents, there were both similarities and differences among the five samples. Correlation analysis of DGGEs' band and 24 effective components revealed a significant correlations (P < 0.01). For examples, 4 bands (15, 18, 23 and 26) were all significantly correlated with the accumulations of caffeic acid, salvianolic acid B, salvianolic acid C and dihydrotanshinone I. PMID:26666030

  15. Calcium signaling in taste cells.

    PubMed

    Medler, Kathryn F

    2015-09-01

    The sense of taste is a common ability shared by all organisms and is used to detect nutrients as well as potentially harmful compounds. Thus taste is critical to survival. Despite its importance, surprisingly little is known about the mechanisms generating and regulating responses to taste stimuli. All taste responses depend on calcium signals to generate appropriate responses which are relayed to the brain. Some taste cells have conventional synapses and rely on calcium influx through voltage-gated calcium channels. Other taste cells lack these synapses and depend on calcium release to formulate an output signal through a hemichannel. Beyond establishing these characteristics, few studies have focused on understanding how these calcium signals are formed. We identified multiple calcium clearance mechanisms that regulate calcium levels in taste cells as well as a calcium influx that contributes to maintaining appropriate calcium homeostasis in these cells. Multiple factors regulate the evoked taste signals with varying roles in different cell populations. Clearly, calcium signaling is a dynamic process in taste cells and is more complex than has previously been appreciated. This article is part of a Special Issue entitled: 13th European Symposium on Calcium. PMID:25450977

  16. Foliar uptake of cesium, iodine and strontium and their transfer to the edible parts of beans, potatoes and radishes

    NASA Astrophysics Data System (ADS)

    Oestling, O.; Kopp, P.; Burkart, W.

    Considerable fractions of radionuclide solutions deposited on the surface of the leaves may be transferred to the edible parts of plants. In radishes we observed a transfer of more than 40% of the applied cesium radioisotope within a few days. A rather similar uptake was found for beans and potatoes when harvested a month after application of radioactivity. As much as 60% of the applied cesium-isotope remained in (or on) the potato leaves even 8 days after application. The major part could however be washed off the leaves a few hours after application. When radishes were showered with water within 7 h after the application of activity the uptake was greatly reduced. No competitive effect of potassium chloride for the foliar uptake of cesium was found. A 10 -2 M colloidal suspension of Prussian Blue, a chelating agent for monovalent alkali metals such as potassium, cesium, or other monovalent cations, applied as droplets to the leaves one day prior to application of active cesium was found to strongly inhibit the transfer of cesium to the radish. The transfer of iodine and strontium to the edible parts was found to be negligible (or slower) as compared to cesium. In most cases no detectable amounts of these two nuclides were transfered to the edible parts of the radish after 2-5 weeks.

  17. Calcium regulation of keratinocyte differentiation

    PubMed Central

    Bikle, Daniel D; Xie, Zhongjian; Tu, Chia-Ling

    2012-01-01

    Calcium is the major regulator of keratinocyte differentiation in vivo and in vitro. A calcium gradient within the epidermis promotes the sequential differentiation of keratinocytes as they traverse the different layers of the epidermis to form the permeability barrier of the stratum corneum. Calcium promotes differentiation by both outsidein and insideout signaling. A number of signaling pathways involved with differentiation are regulated by calcium, including the formation of desmosomes, adherens junctions and tight junctions, which maintain cellcell adhesion and play an important intracellular signaling role through their activation of various kinases and phospholipases that produce second messengers that regulate intracellular free calcium and PKC activity, critical for the differentiation process. The calcium receptor plays a central role by initiating the intracellular signaling events that drive differentiation in response to extracellular calcium. This review will discuss these mechanisms. PMID:23144648

  18. Transcriptome analysis of Fusarium virguliforme provides additional evidence of toxins that contribute to foliar symptoms of soybean sudden death syndrome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxins produced by the soil-borne fungus, Fusarium virguliforme, cause foliar symptoms in soybean. The disease in soybean is referred to as soybean sudden death syndrome (SDS). Three toxins produced by the fungus were reported to be associated with SDS foliar symptoms, but none produced identical S...

  19. Eleven-year response of foliar chemistry to chronic nitrogen and sulfur additions at the Bear Brooks Watershed in Maine

    SciTech Connect

    Jose Alexander Elvir; Gregory J. White

    2005-06-01

    The foliar chemistry of sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since 1989 with ammonium sulfate ((NH4)2SO4) at a rate of 25.2 kg N·ha–1·year–1. Foliar N concentrations were higher in all tree species within the treated watershed compared with trees within the reference watershed. Foliar Ca and Mg concentrations were lower in American beech and red spruce within the treated watershed. There were no significant differences in foliar K concentrations between watersheds. Foliar P and Mn concentration differences between watersheds were inconsistent among years. Differences in foliar N concentrations between watersheds declined over time in sugar maple but not in red spruce or American beech. Differences in foliar Ca and Mg concentrations between the treated and reference watersheds increased over time for American beech and red spruce, primarily because of a consistent decline in concentrations of these nutrients in trees within the treated watershed. No temporal trends in foliar Ca and Mg concentration differences between watersheds were observed for sugar maple.

  20. IDENTIFICATION AND USE OF SOLANUM TUBEROSUM SUBSP. ANDIGENA CLONES HAVING BOTH FOLIAR AND TUBER RESISTANCE TO LATE BLIGHT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breeding solely for foliar resistance to late blight without emphasis on tuber resistance has the potential to exacerbate tuber infection. Wild potato species are valuable sources of foliar and tuber blight resistance. However, most species are difficult to sexually hybridize with cultivated potat...

  1. Effect of Glyphosate-boron Application on Seed Composition and Nitrogen Metabolism in Glyphosate-resistant Soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information is limited on the effect of combined foliar application of glyphosate (Gly) and boron (B) on seed composition and nitrogen metabolism in glyphosate resistant soybean (Glycine max(L.)Merr.). Therefore, the objective of this two-year field study was to evaluate the effects of single foliar...

  2. Antagonist effects of calcium on borosilicate glass alteration

    NASA Astrophysics Data System (ADS)

    Mercado-Depierre, S.; Angeli, F.; Frizon, F.; Gin, S.

    2013-10-01

    Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon-calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass-cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C-S-H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon-calcium interactions on glass durability and open the way for a better understanding of glass-cement mixing in civil engineering applications as well as in nuclear waste storage.

  3. DISTILLATION OF CALCIUM

    DOEpatents

    Barton, J.

    1954-07-27

    This invention relates to an improvement in the process for the purification of caicium or magnesium containing an alkali metal as impurity, which comprises distiiling a batch of the mixture in two stages, the first stage distillation being carried out in the presence of an inert gas at an absolute pressure substantially greater than the vapor pressure of calcium or maguesium at the temperature of distillation, but less than the vaper pressure at that temperature of the alkali metal impurity so that only the alkali metal is vaporized and condensed on a condensing surface. A second stage distilso that substantially only the calcium or magnesium distills under its own vapor pressure only and condenses in solid form on a lower condensing surface.

  4. Synthesis of calcium superoxide

    NASA Technical Reports Server (NTRS)

    Rewick, R. T.; Blucher, W. G.; Estacio, P. L.

    1972-01-01

    Efforts to prepare Ca(O2) sub 2 from reactions of calcium compounds with 100% O3 and with O(D-1) atoms generated by photolysis of O3 at 2537 A are described. Samples of Ca(OH) sub 2, CaO, CaO2, Ca metal, and mixtures containing suspected impurities to promote reaction have been treated with excess O3 under static and flow conditions in the presence and absence of UV irradiation. Studies with KO2 suggest that the superoxide anion is stable to radiation at 2537 A but reacts with oxygen atoms generated by the photolysis of O3 to form KO3. Calcium superoxide is expected to behave in an analogous.

  5. Calcium in Plants

    PubMed Central

    WHITE, PHILIP J.; BROADLEY, MARTIN R.

    2003-01-01

    Calcium is an essential plant nutrient. It is required for various structural roles in the cell wall and membranes, it is a counter?cation for inorganic and organic anions in the vacuole, and the cytosolic Ca2+ concentration ([Ca2+]cyt) is an obligate intracellular messenger coordinating responses to numerous developmental cues and environmental challenges. This article provides an overview of the nutritional requirements of different plants for Ca, and how this impacts on natural flora and the Ca content of crops. It also reviews recent work on (a) the mechanisms of Ca2+ transport across cellular membranes, (b) understanding the origins and specificity of [Ca2+]cyt signals and (c) characterizing the cellular [Ca2+]cyt?sensors (such as calmodulin, calcineurin B?like proteins and calcium?dependent protein kinases) that allow plant cells to respond appropriately to [Ca2+]cyt signals. PMID:12933363

  6. Nutrition in calcium nephrolithiasis

    PubMed Central

    2013-01-01

    Idiopathic calcium nephrolithiasis is a multifactorial disease with a complex pathogenesis due to genetic and environmental factors. The importance of social and health effects of nephrolithiasis is further highlighted by the strong tendency to relapse of the disease. Long-term prospective studies show a peak of disease recurrence within 23years since onset, 40-50% of patients have a recurrence after 5years and more than 50-60% after 10years. International nutritional studies demonstrated that nutritional habits are relevant in therapy and prevention approaches of nephrolithiasis. Water, right intake of calcium, low intake of sodium, high levels of urinary citrate are certainly important for the primary and secondary prevention of nephrolithiasis. In this review is discussed how the correction of nutritional mistakes can reduce the incidence of recurrent nephrolithiasis. PMID:23634702

  7. Magnetic resonance imaging of sugar beet taproots in soil reveals growth reduction and morphological changes during foliar Cercospora beticola infestation

    PubMed Central

    Schmittgen, Simone; Metzner, Ralf; Van Dusschoten, Dagmar; Jansen, Marcus; Fiorani, Fabio; Jahnke, Siegfried; Rascher, Uwe; Schurr, Ulrich

    2015-01-01

    Cercospora leaf spot (CLS) infection can cause severe yield loss in sugar beet. Introduction of Cercospora-resistant varieties in breeding programmes is important for plant protection to reduce both fungicide applications and the risk of the development of fungal resistance. However, in vivo monitoring of the sugar-containing taproots at early stages of foliar symptoms and the characterization of the temporal development of disease progression has proven difficult. Non-invasive magnetic resonance imaging (MRI) measurements were conducted to quantify taproot development of genotypes with high (HS) and low (LS) levels of susceptibility after foliar Cercospora inoculation. Fourteen days post-inoculation (dpi) the ratio of infected leaf area was still low (~7%) in both the HS and LS genotypes. However, during this period, the volumetric growth of the taproot had already started to decrease. Additionally, inoculated plants showed a reduction of the increase in width of inner cambial rings while the width of outer rings increased slightly compared with non-inoculated plants. This response partly compensated for the reduced development of inner rings that had a vascular connection with Cercospora-inoculated leaves. Hence, alterations in taproot anatomical features such as volume and cambial ring development can be non-invasively detected already at 14 dpi, providing information on the early impact of the infection on whole-plant performance. All these findings show that MRI is a suitable tool to identify promising candidate parent lines with improved resistance to Cercospora, for example with comparatively lower taproot growth reduction at early stages of canopy infection, for future introduction into breeing programmes. PMID:25873673

  8. Magnetic resonance imaging of sugar beet taproots in soil reveals growth reduction and morphological changes during foliar Cercospora beticola infestation.

    PubMed

    Schmittgen, Simone; Metzner, Ralf; Van Dusschoten, Dagmar; Jansen, Marcus; Fiorani, Fabio; Jahnke, Siegfried; Rascher, Uwe; Schurr, Ulrich

    2015-09-01

    Cercospora leaf spot (CLS) infection can cause severe yield loss in sugar beet. Introduction of Cercospora-resistant varieties in breeding programmes is important for plant protection to reduce both fungicide applications and the risk of the development of fungal resistance. However, in vivo monitoring of the sugar-containing taproots at early stages of foliar symptoms and the characterization of the temporal development of disease progression has proven difficult. Non-invasive magnetic resonance imaging (MRI) measurements were conducted to quantify taproot development of genotypes with high (HS) and low (LS) levels of susceptibility after foliar Cercospora inoculation. Fourteen days post-inoculation (dpi) the ratio of infected leaf area was still low (~7%) in both the HS and LS genotypes. However, during this period, the volumetric growth of the taproot had already started to decrease. Additionally, inoculated plants showed a reduction of the increase in width of inner cambial rings while the width of outer rings increased slightly compared with non-inoculated plants. This response partly compensated for the reduced development of inner rings that had a vascular connection with Cercospora-inoculated leaves. Hence, alterations in taproot anatomical features such as volume and cambial ring development can be non-invasively detected already at 14 dpi, providing information on the early impact of the infection on whole-plant performance. All these findings show that MRI is a suitable tool to identify promising candidate parent lines with improved resistance to Cercospora, for example with comparatively lower taproot growth reduction at early stages of canopy infection, for future introduction into breeing programmes. PMID:25873673

  9. Magnesium, calcium and cancer.

    PubMed

    Anghileri, Leopoldo J

    2009-12-01

    Magnesium ion (Mg(2+)) and calcium ion (Ca(2+)) control a diverse and important range of cellular processes, such as gene transcription, cell proliferation, neoplastic transformation, immune response and therapeutic treatment. Their characteristic biologic antagonism makes it important to treat the most important aspects of that competitive behavior together. This synopsis aims to be a useful means of promoting further research on the relationship between both cations and human health affected by environmental conditions. PMID:20228002

  10. [Paramagnetic calcium melanins].

    PubMed

    Lebedev, A V; Ivanova, M V; Timoshin, A A; Ruuge, E K

    2013-01-01

    Treatment of catechol, pyrogallol, DOPA, dopamine, norepinephrine, and natural polyhydroxy-1,4-naphthoquinone echinochrome by aqueous solution of potassium superoxide (KO2) in the presence of CaCl2 leads to the formation of water-insoluble dark pigments with stable paramagnetic properties ("calcium melanins"). In control experiments in the same procedure without Ca2+, the pigments were not formed. EPR spectra of the calcium melanins had little difference from each other and from known melanins in shape, line width, and the g factor about 2,004. Addition of EDTA water solution to dried paramagnetic pigments leads to their fast dissolving and disappearing of EPR signal. Formation of similar polymers is also observed during autoxidation of o-diphenols in Ca(2+)-containing alkaline buffer solution, however, this process takes a few days instead of few seconds in the presence of KO2. Thus, calcium (and other divalent cation M2+) can consider as a key structural element in formation of M(2+)-catecholate paramagnetic Polymer. We assume the existence of two types of paramagnetic centers in melanin-like polymer: M(2+)-stabilized o-semiquinone radical or bi-radical complex containing o-semiquinone and superoxide anion radicals, stabilized by M2+. PMID:23650854

  11. Metabolomic assessment reveals a stimulatory effect of calcium treatment on glucosinolates contents in broccoli microgreen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Preharvest calcium application has been shown to increase broccoli microgreen yield and extend shelf life. Here we investigated the effect of calcium application on its metabolome using ultra high-performance liquid chromatography (UHPLC) tandem with mass spectrometry (HRMS). The data collected were...

  12. Assessment of crop foliar nitrogen using a novel dual-wavelength laser system and implications for conducting laser-based plant physiology

    NASA Astrophysics Data System (ADS)

    Eitel, Jan U. H.; Magney, Troy S.; Vierling, Lee A.; Dittmar, Günter

    2014-11-01

    Advanced technologies for improved nitrogen (N) fertilizer management are paramount for sustainably meeting future food demands. Green laser systems that measure pulse return intensity can provide more reliable information about foliar N than can traditional passive remote sensing devices during the critical early crop growth stages (e.g., before canopy closure when vegetation and soil signals are spectrally mixed) when further decisions regarding N management can be made. However, current green laser systems are not designed for agricultural applications and only employ a single green laser wavelength, which may limit applications because many factors that require normalization techniques can affect pulse return intensity. Here, we describe the design of a tractor-mountable, green (532 nm)- and red (658 nm) dual wavelength laser system and evaluate the potential of an additional red reference wavelength to improve laser based estimates of foliar N by calculating laser spectral indices based on ratio combinations of green laser return intensity (GLRI) and red laser return intensity (RLRI). We hypothesized that such laser spectral indices aid in accounting for factors that confound laser based foliar N estimates including variations in leaf angle, measurement distance, soil returns, and mixed edge returns. Leaf level measurements in winter wheat (Triticum aestivum) revealed that the two laser spectral indices improved the relationship with foliar N (r2 > 0.71, RMSE < 0.28%) compared to the sole use of GLRI (r2 = 0.47, RMSE = 0.38%). Laboratory measurements also showed that laser spectral indices reduced the effect of measurement distance on laser readings and allowed leaf returns to be better separated from edge returns and soil returns. However, laboratory measurements showed that laser spectral indices did not account for variations in leaf angle, possibly explaining the weak relationships (r2 < 0.36, RMSE = 0.49%) between foliar N and laser spectral indices observed when employing the laser system under field conditions. In fact, the strongest relationship at the field canopy level was shown for GLRI (r2 = 0.65, RMSE = 0.37%) alone. Laboratory measurements suggest that the better performance of GLRI compared to ratio-based laser spectral indices may result from pronounced differences in the leaf-level bidirectional reflectance distribution factor (BRDFleaf) between the green and red laser wavelengths, thus confounding leaf angle effects so that they are not cancelled when calculating laser spectral indices. This finding suggests that the small spot size of the laser pulses (⩽5 mm diameter) interacts with BRDFleaf at very fine scales, therefore causing differential, wavelength-specific scattering effects. Additional study of BRDFleaf at the mm scale is therefore warranted, and should be carefully considered in future development and use of multi-wavelength laser systems for remotely sensing foliar biochemistry.

  13. Calcium spikes: Chance or necessity?

    NASA Astrophysics Data System (ADS)

    Jung, Peter; Swaminathan, Divya; Ullah, Aman

    2010-10-01

    Calcium oscillations present one of the most important signaling mechanisms in cell biology. The standard paradigm for the origin of calcium oscillations is dynamic, i.e. fast release of calcium from intracellular stores is followed by slow inhibition. Yet, this very dynamic theory for these oscillations came recently into scrutiny since the building blocks of cellular calcium signals are spatially and temporally limited calcium release events through small, distinct cluster of ion channels. According to this new paradigm, a coherent wave of calcium release, triggered by stochastic release events from a group of clusters, sweeps the cell. Oscillations are believed to emerge through a spatial coherence resonance mechanism. In this paper we investigate the difference in stochastic spiking generated by a small periodic system and a small excitable system and compare with published experimental data.

  14. Sensitivity of soybean plant introductions to the foliar fungicide tebuconazole (Folicur)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nearly 100 plant introductions, ranging in maturity from 0 to IX and representing over 90% of the current commercial germplasm, were planted in 2 replications of 1 row plots 2.4 m long. Tebuconazole was applied at R1 and R3 at 4.0 oz/acre. Evaluation was done in both 2006 and 2007 with foliar sympto...

  15. Cold hardiness and foliar disease resistance of North American and Asian Fragaria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-two wild strawberry genotypes and two commercial cultivars were obtained from the US Department of Agriculture (USDA), Agricultural Research Service (ARS), National Clonal Germplasm Repository-Corvallis (NCGR) and planted in the field to test cold hardiness and foliar disease resistance at th...

  16. Mapping Disease Resistance QTL for Three Foliar Diseases of Maize in a RIL Population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Southern leaf blight (SLB), gray leaf spot (GLS), and northern leaf blight (NLB) are three important foliar diseases impacting maize production. The objectives of this study were to identify quantitative trait loci for disease resistance (dQTL) for resistance to these diseases in a maize recombinan...

  17. Foliar water uptake: a common water acquisition strategy for plants of the redwood forest.

    PubMed

    Limm, Emily Burns; Simonin, Kevin A; Bothman, Aron G; Dawson, Todd E

    2009-09-01

    Evaluations of plant water use in ecosystems around the world reveal a shared capacity by many different species to absorb rain, dew, or fog water directly into their leaves or plant crowns. This mode of water uptake provides an important water subsidy that relieves foliar water stress. Our study provides the first comparative evaluation of foliar uptake capacity among the dominant plant taxa from the coast redwood ecosystem of California where crown-wetting events by summertime fog frequently occur during an otherwise drought-prone season. Previous research demonstrated that the dominant overstory tree species, Sequoia sempervirens, takes up fog water by both its roots (via drip from the crown to the soil) and directly through its leaf surfaces. The present study adds to these early findings and shows that 80% of the dominant species from the redwood forest exhibit this foliar uptake water acquisition strategy. The plants studied include canopy trees, understory ferns, and shrubs. Our results also show that foliar uptake provides direct hydration to leaves, increasing leaf water content by 2-11%. In addition, 60% of redwood forest species investigated demonstrate nocturnal stomatal conductance to water vapor. Such findings indicate that even species unable to absorb water directly into their foliage may still receive indirect benefits from nocturnal leaf wetting through suppressed transpiration. For these species, leaf-wetting events enhance the efficacy of nighttime re-equilibration with available soil water and therefore also increase pre-dawn leaf water potentials. PMID:19585154

  18. Evolution of a complex behavior: the origin and initial diversification of foliar galling by Permian insects.

    PubMed

    Schachat, Sandra R; Labandeira, Conrad C

    2015-04-01

    A central notion of the early evolution of insect galling is that this unique behavior was uncommon to rare before the diversification of angiosperms 135 to 125 m.yr. ago. However, evidence accumulated during recent years shows that foliar galls were diverse and locally abundant as early as the Permian Period, 299 to 252 m.yr. ago. In particular, a diversity of leaf galling during the Early Permian has recently been documented by the plant-damage record of foliar galls and, now, our interpretation of the body-fossil record of culprit insect gallers. Small size is a prerequisite for gallers. Wing-length measurements of Permian insects indicate that several small-bodied hemipteroid lineages originated early during the Permian, some descendant lineages of which gall the leaves of seed plants to the present day. The earliest foliar gallers likely were Protopsyllidiidae (Hemiptera) and Lophioneuridae (Thripida). Much of the Early Permian was a xeric interval, and modern galls are most common in dry, extra-tropical habitats such as scrubland and deserts. Plant-damage, insect body fossils, and the paleoclimate record collectively support the ecological expansion of foliar galling during the Early Permian and its continued expansion through the Late Permian. PMID:25783809

  19. Evolution of a complex behavior: the origin and initial diversification of foliar galling by Permian insects

    NASA Astrophysics Data System (ADS)

    Schachat, Sandra R.; Labandeira, Conrad C.

    2015-04-01

    A central notion of the early evolution of insect galling is that this unique behavior was uncommon to rare before the diversification of angiosperms 135 to 125 m.yr. ago. However, evidence accumulated during recent years shows that foliar galls were diverse and locally abundant as early as the Permian Period, 299 to 252 m.yr. ago. In particular, a diversity of leaf galling during the Early Permian has recently been documented by the plant-damage record of foliar galls and, now, our interpretation of the body-fossil record of culprit insect gallers. Small size is a prerequisite for gallers. Wing-length measurements of Permian insects indicate that several small-bodied hemipteroid lineages originated early during the Permian, some descendant lineages of which gall the leaves of seed plants to the present day. The earliest foliar gallers likely were Protopsyllidiidae (Hemiptera) and Lophioneuridae (Thripida). Much of the Early Permian was a xeric interval, and modern galls are most common in dry, extra-tropical habitats such as scrubland and deserts. Plant-damage, insect body fossils, and the paleoclimate record collectively support the ecological expansion of foliar galling during the Early Permian and its continued expansion through the Late Permian.

  20. Effects of Foliar Fertilizer and Mepiquat Penteborate on Early Planted Cotton Growth and Lint Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple growth regulators and foliar fertilizers are currently marketed for use in cotton (Gossypium hirsutum L.) with varying effectiveness in promoting yield improvement. This research addressed the effectiveness of these products in a cotton early planting production system with its higher yiel...

  1. Testing Taxonomic Predictivity of Foliar and Tuber Resistance to Phytophthora infestans in Wild Relatives of Potato.

    PubMed

    Khiutti, A; Spooner, D M; Jansky, S H; Halterman, D A

    2015-09-01

    Potato late blight, caused by the oomycete phytopathogen Phytophthora infestans, is a devastating disease found in potato-growing regions worldwide. Long-term management strategies to control late blight include the incorporation of host resistance to predominant strains. However, due to rapid genetic changes within pathogen populations, rapid and recurring identification and integration of novel host resistance traits is necessary. Wild relatives of potato offer a rich source of desirable traits, including late blight resistance, but screening methods can be time intensive. We tested the ability of taxonomy, ploidy, crossing group, breeding system, and geography to predict the presence of foliar and tuber late blight resistance in wild Solanum spp. Significant variation for resistance to both tuber and foliar late blight was found within and among species but there was no discernable predictive power based on taxonomic series, clade, ploidy, breeding system, elevation, or geographic location. We observed a moderate but significant correlation between tuber and foliar resistance within species. Although previously uncharacterized sources of both foliar and tuber resistance were identified, our study does not support an assumption that taxonomic or geographic data can be used to predict sources of late blight resistance in wild Solanum spp. PMID:25871860

  2. HERITABILITY OF TOLERANCE TO EARLY FOLIAR DECLINE IN THREE AMERICAN PIMA COTTON POPULATIONS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early foliar decline (EFD) is a recurring problem of Pima cotton (Gossypium barbadense L.) in the San Joaquin Valley of California where it has been implicated in yield and fiber quality losses. Anecdotal evidence indicates that genetic variability for tolerance to EFD exists within Pima germplasm....

  3. DEFENDER: A HIGH-YIELDING, PROCESSING POTATO CULTIVAR WITH FOLIAR AND TUBER RESISTANCE TO LATE BLIGHT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato cultivar ‘Defender’ has resistance to both foliar and tuber infection by newer genotypes of Phytophthora infestans. Resistance was derived from its Polish parent, KSA195-90. Released in 2004, Defender is high yielding, white-skinned, and suitable for processing into frozen potato products di...

  4. Inheritance of fruit, foliar and plant habit attributes in Capsicum L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Considerable diversity exists in Capsicum L. germplasm for fruit and leaf shape and size, as well as plant habit. Utilizing F1, F2 and backcross generations developed from diverse parental stocks, this report describes the inheritance patterns and relationships between unique foliar characters and ...

  5. CORRELATION BETWEEN OZONE EXPOSURE AND VISIBLE FOLIAR INJURY IN PONDEROSA AND JEFFREY PINES. (R825433)

    EPA Science Inventory

    Ozone exposure was related to ozone-induced visible foliar injury in ponderosa and Jeffrey pines growing on the western slopes of the Sierra Nevada Mountains of California. Measurements of ozone exposure, chlorotic mottle and fascicle retention were collected during the years ...

  6. Neonicotinoid Seed Treatments and Foliar Sprays on Sugarbeet for Control of Severe Curly Top

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarbeet production in semiarid regions is hindered by yield loss caused with Beet severe curly top virus and other closely related species vectored by the beet leafhopper. In 2010, a study was established to investigate the level of control from seed treatments and supplemental foliar insecticide...

  7. Relative contribution of seed-transmitted inoculum to foliar populations of Phaeosphaeria nodorum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A marked-isolate, release-recapture experiment was conducted to assess the relative contributions of seed-transmitted (released isolates) versus all other inocula to foliar and grain populations of Phaeosphaeria nodorum in winter wheat rotated with nonsusceptible crops in New York and Georgia, USA. ...

  8. Relationships between C3 Plant Foliar Carbon Isotope Composition and Element Contents of Grassland Species at High Altitudes on the Qinghai-Tibet Plateau, China

    PubMed Central

    Zhou, Yong-Chun; Fan, Jiang-Wen; Harris, Warwick; Zhong, Hua-Ping; Zhang, Wen-Yan; Cheng, Xi-Lei

    2013-01-01

    Relationships of foliar carbon isotope composition (δ13C) with foliar C, N, P, K, Ca, Mg contents and their ratios of 219 C3 species leaf samples, obtained in August in 2004 to 2007 from 82 high altitude grassland sites on the Qinghai-Tibet Plateau China, were examined. This was done with reference to the proposition that foliar δ13C increases with altitude and separately for the life-form groups of graminoids, forbs and shrubs and for the genera Stipa and Kobresia. For all samples, foliar δ13C was negatively related to foliar K, P and ∑K+ Ca+ Mg, and positively correlated to foliar C, C/N and C/P. The significance of these correlations differed for the taxonomic and life-form groups. Lack of a relationship of foliar δ13C with foliar N was inconsistent with the majority of studies that have shown foliar δ13C to be positively related to foliar N due to a decrease of Ci/Ca (the ratio between intercellular and atmospheric concentration of CO2) and explained as a result of greater photosynthetic capacity at higher foliar N concentration. However this inconsistency relates to other high altitude studies that have found that photosynthetic capacity remains constant as foliar N increases. After accounting for the altitudinal relationship with foliar δ13C, of the elements only the K effect was significant and was most strongly expressed for Kobresia. It is concluded that factors critical to plant survival and growth at very high altitudes, such as low atmospheric pressure and low temperatures, may preclude expression of relationships between foliar δ13C and foliar elements that have been observed at lower altitudes. PMID:23565275

  9. Calcium Kinetics During Space Flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.; Wastney, Meryl E.; OBrien, Kimberly O.; Lane, Helen W.

    1999-01-01

    Bone loss is one of the most detrimental effects of space flight, threatening to limit the duration of human space missions. The ability to understand and counteract this loss will be critical for crew health and safety during and after extended-duration missions. The hypotheses to be tested in this project are that space flight alters calcium homeostasis and bone mineral metabolism, and that calcium homeostasis and bone mineral metabolism will return to baseline within days to weeks of return to Earth. These hypotheses will be evidenced by elevated rates of bone mineral resorption and decreased bone mineral deposition, decreased absorption of dietary calcium, altered calcitropic endocrine profiles, elevated excretion of calcium in urine and feces, and elevated excretion of markers of bone resorption. The second hypothesis will be evidenced by return of indices of calcium homeostasis and bone metabolism to preflight levels within days to weeks of return to Earth. Studies will be conducted on International Space Station astronauts before, during, and after extended-duration flights. Measurements of calcium kinetics, bone mass, and endocrine/biochemical markers of bone and calcium homeostasis will be conducted. Kinetic studies utilizing dual isotope tracer kinetic studies and mathematical modeling techniques will allow for determination of bone calcium deposition, bone calcium resorption, dietary calcium absorption and calcium excretion (both urinary and endogenous fecal excretion). These studies will build upon preliminary work conducted on the Russian Mir space station. The results from this project will be critical for clarifying how microgravity affects bone and calcium homeostasis, and will provide an important control point for assessment of countermeasure efficacy. These results are expected to aid in developing countermeasures for bone loss, both for space crews and for individuals on Earth who have metabolic bone diseases.

  10. Theoretical aspects of calcium signaling

    NASA Astrophysics Data System (ADS)

    Pencea, Corneliu Stefan

    2001-08-01

    Experiments investigating intracellular calcium dynamics have revealed that calcium signals differentially affect a variety of intracellular processes, from fertilization and cell development and differentiation to subsequent cellular activity, ending with cell death. As an intracellular messenger, calcium transmits information within and between cells, thus regulating their activity. To control such a variety of processes, calcium signals have to be very flexible and also precisely regulated. The cell uses a calcium signaling ``toolkit'', where calcium ions can act in different contexts of space, amplitude and time. For different tasks, the cell selects the particular signal, or combination of signals, that triggers the appropriate physiological response. The physical foundations of such a versatile cellular signaling toolkit involving calcium are not completely understood, despite important experimental and theoretical progress made recently. The declared goal of this work is to investigate physical mechanisms on which the propagation of differential signals can be based. The dynamics of calcium near a cluster of inositol trisphosphate (IP3) activated calcium channels has been investigated analytically and numerically. Our work has demonstrated that clusters of different IP3 receptors can show similar bistable behavior, but differ in both the transient and long term dynamics. We have also investigated the conditions under which a calcium signal propagates between a pair of localized stores. We have shown that the propagation of the signal across a random distribution of such stores shows a percolation transition manifested in the shape of the wave front. More importantly, our work indicates that specific distribution of stores can be interpreted as calcium circuits that can perform important signal analyzing task, from unidirectional propagation and coincidence detection to a complete set of logic gates. We believe that phenomena like the ones described are relevant in the processing of biological signals, contributing to the versatility of the calcium signaling toolkit.

  11. Cameleon calcium indicator reports cytoplasmic calcium dynamics in Arabidopsis guard cells.

    PubMed

    Allen, G J; Kwak, J M; Chu, S P; Llopis, J; Tsien, R Y; Harper, J F; Schroeder, J I

    1999-09-01

    Cytoplasmic free calcium ([Ca2+]cyt) acts as a stimulus-induced second messenger in plant cells and multiple signal transduction pathways regulate [Ca2+]cyt in stomatal guard cells. Measuring [Ca2+]cyt in guard cells has previously required loading of calcium-sensitive dyes using invasive and technically difficult micro-injection techniques. To circumvent these problems, we have constitutively expressed the pH-independent, green fluorescent protein-based calcium indicator yellow cameleon 2.1 in Arabidopsis thaliana (Miyawaki et al. 1999; Proc. Natl. Acad. Sci. USA 96, 2135-2140). This yellow cameleon calcium indicator was expressed in guard cells and accumulated predominantly in the cytoplasm. Fluorescence ratio imaging of yellow cameleon 2.1 allowed time-dependent measurements of [Ca2+]cyt in Arabidopsis guard cells. Application of extracellular calcium or the hormone abscisic acid (ABA) induced repetitive [Ca2+]cyt transients in guard cells. [Ca2+]cyt changes could be semi-quantitatively determined following correction of the calibration procedure for chloroplast autofluorescence. Extracellular calcium induced repetitive [Ca2+]cyt transients with peak values of up to approximately 1.5 microM, whereas ABA-induced [Ca2+]cyt transients had peak values up to approximately 0.6 microM. These values are similar to stimulus-induced [Ca2+]cyt changes previously reported in plant cells using ratiometric dyes or aequorin. In some guard cells perfused with low extracellular KCl concentrations, spontaneous calcium transients were observed. As yellow cameleon 2.1 was expressed in all guard cells, [Ca2+]cyt was measured independently in the two guard cells of single stomates for the first time. ABA-induced, calcium-induced or spontaneous [Ca2+]cyt increases were not necessarily synchronized in the two guard cells. Overall, these data demonstrate that that GFP-based cameleon calcium indicators are suitable to measure [Ca2+]cyt changes in guard cells and enable the pattern of [Ca2+]cyt dynamics to be measured with a high level of reproducibility in Arabidopsis cells. This technical advance in combination with cell biological and molecular genetic approaches will become an invaluable tool in the dissection of plant cell signal transduction pathways. PMID:10571859

  12. Cameleon calcium indicator reports cytoplasmic calcium dynamics in Arabidopsis guard cells

    NASA Technical Reports Server (NTRS)

    Allen, G. J.; Kwak, J. M.; Chu, S. P.; Llopis, J.; Tsien, R. Y.; Harper, J. F.; Schroeder, J. I.; Evans, M. L. (Principal Investigator)

    1999-01-01

    Cytoplasmic free calcium ([Ca2+]cyt) acts as a stimulus-induced second messenger in plant cells and multiple signal transduction pathways regulate [Ca2+]cyt in stomatal guard cells. Measuring [Ca2+]cyt in guard cells has previously required loading of calcium-sensitive dyes using invasive and technically difficult micro-injection techniques. To circumvent these problems, we have constitutively expressed the pH-independent, green fluorescent protein-based calcium indicator yellow cameleon 2.1 in Arabidopsis thaliana (Miyawaki et al. 1999; Proc. Natl. Acad. Sci. USA 96, 2135-2140). This yellow cameleon calcium indicator was expressed in guard cells and accumulated predominantly in the cytoplasm. Fluorescence ratio imaging of yellow cameleon 2.1 allowed time-dependent measurements of [Ca2+]cyt in Arabidopsis guard cells. Application of extracellular calcium or the hormone abscisic acid (ABA) induced repetitive [Ca2+]cyt transients in guard cells. [Ca2+]cyt changes could be semi-quantitatively determined following correction of the calibration procedure for chloroplast autofluorescence. Extracellular calcium induced repetitive [Ca2+]cyt transients with peak values of up to approximately 1.5 microM, whereas ABA-induced [Ca2+]cyt transients had peak values up to approximately 0.6 microM. These values are similar to stimulus-induced [Ca2+]cyt changes previously reported in plant cells using ratiometric dyes or aequorin. In some guard cells perfused with low extracellular KCl concentrations, spontaneous calcium transients were observed. As yellow cameleon 2.1 was expressed in all guard cells, [Ca2+]cyt was measured independently in the two guard cells of single stomates for the first time. ABA-induced, calcium-induced or spontaneous [Ca2+]cyt increases were not necessarily synchronized in the two guard cells. Overall, these data demonstrate that that GFP-based cameleon calcium indicators are suitable to measure [Ca2+]cyt changes in guard cells and enable the pattern of [Ca2+]cyt dynamics to be measured with a high level of reproducibility in Arabidopsis cells. This technical advance in combination with cell biological and molecular genetic approaches will become an invaluable tool in the dissection of plant cell signal transduction pathways.

  13. Coupled nitrogen and calcium cycling in forests of the Oregon Coast Range

    USGS Publications Warehouse

    Perakis, Steven S.; Maguire, Douglas A.; Bullen, Thomas D.; Cromack, Kermit; Waring, Richard H.; Boyle, James R.

    2006-01-01

    Nitrogen (N) is a critical limiting nutrient that regulates plant productivity and the cycling of other essential elements in forests. We measured foliar and soil nutrients in 22 young Douglas-fir stands in the Oregon Coast Range to examine patterns of nutrient availability across a gradient of N-poor to N-rich soils. N in surface mineral soil ranged from 0.15 to 1.05% N, and was positively related to a doubling of foliar N across sites. Foliar N in half of the sites exceeded 1.4% N, which is considered above the threshold of N-limitation in coastal Oregon Douglas-fir. Available nitrate increased five-fold across this gradient, whereas exchangeable magnesium (Mg) and calcium (Ca) in soils declined, suggesting that nitrate leaching influences base cation availability more than soil parent material across our sites. Natural abundance strontium isotopes (87Sr/86Sr) of a single site indicated that 97% of available base cations can originate from atmospheric inputs of marine aerosols, with negligible contributions from weathering. Low annual inputs of Ca relative to Douglas-fir growth requirements may explain why foliar Ca concentrations are highly sensitive to variations in soil Ca across our sites. Natural abundance calcium isotopes (I'44Ca) in exchangeable and acid leachable pools of surface soil measured at a single site showed 1 per mil depletion relative to deep soil, suggesting strong Ca recycling to meet tree demands. Overall, the biogeochemical response of these Douglas-fir forests to gradients in soil N is similar to changes associated with chronic N deposition in more polluted temperate regions, and raises the possibility that Ca may be deficient on excessively N-rich sites. We conclude that wide gradients in soil N can drive non-linear changes in base-cation biogeochemistry, particularly as forests cross a threshold from N-limitation to N-saturation. The most acute changes may occur in forests where base cations are derived principally from atmospheric inputs.

  14. Coupled nitrogen and calcium cycles in forests of the Oregon Coast Range

    USGS Publications Warehouse

    Perakis, S.S.; Maguire, D.A.; Bullen, T.D.; Cromack, K.; Waring, R.H.; Boyle, J.R.

    2006-01-01

    Nitrogen (N) is a critical limiting nutrient that regulates plant productivity and the cycling of other essential elements in forests. We measured foliar and soil nutrients in 22 young Douglas-fir stands in the Oregon Coast Range to examine patterns of nutrient availability across a gradient of N-poor to N-rich soils. N in surface mineral soil ranged from 0.15 to 1.05% N, and was positively related to a doubling of foliar N across sites. Foliar N in half of the sites exceeded 1.4% N, which is considered above the threshold of N-limitation in coastal Oregon Douglas-fir. Available nitrate increased five-fold across this gradient, whereas exchangeable magnesium (Mg) and calcium (Ca) in soils declined, suggesting that nitrate leaching influences base cation availability more than soil parent material across our sites. Natural abundance strontium isotopes (87Sr/86Sr) of a single site indicated that 97% of available base cations can originate from atmospheric inputs of marine aerosols, with negligible contributions from weathering. Low annual inputs of Ca relative to Douglas-fir growth requirements may explain why foliar Ca concentrations are highly sensitive to variations in soil Ca across our sites. Natural abundance calcium isotopes (??44Ca) in exchangeable and acid leachable pools of surface soil measured at a single site showed 1 per mil depletion relative to deep soil, suggesting strong Ca recycling to meet tree demands. Overall, the biogeochemical response of these Douglas-fir forests to gradients in soil N is similar to changes associated with chronic N deposition in more polluted temperate regions, and raises the possibility that Ca may be deficient on excessively N-rich sites. We conclude that wide gradients in soil N can drive non-linear changes in base-cation biogeochemistry, particularly as forests cross a threshold from N-limitation to N-saturation. The most acute changes may occur in forests where base cations are derived principally from atmospheric inputs. ?? 2006 Springer Science+Business Media, Inc.

  15. Mechanisms of renal calcium transport.

    PubMed

    Friedman, P A

    2000-01-01

    The kidneys play a key role in the integrated regulation of calcium homeostasis. Calcium absorption takes place throughout the nephron. Proximal tubules, thick ascending limbs of Henle's loop, and distal tubules are the major sites of calcium absorption. The mechanisms of absorption vary significantly from one segment to another, as does the extent of hormonal regulation. At one extreme is the considerable reabsorption by proximal tubules that proceeds primarily, if not entirely, by a paracellular pathway that is not regulated by hormones or drugs. In thick ascending limbs, calcium absorption occurs through a combination of transcellular and paracellular routes. The active, transcellular component is regulated by parathyroid hormone (PTH) and calcitonin, whereas the passive, paracellular route is governed by the extent of concomitant sodium absorption. At the other extreme is the distal tubule, where calcium absorption is entirely transcellular and is regulated by PTH,1,25[OH(2)] vitamin D(3), calcitonin, and by calcium-sparing drugs such as thiazide-type diuretics. The present review focuses on recent insights into the mechanisms of transcellular calcium movement and highlights the discovery of an epithelial calcium channel, ECaC, that may mediate calcium entry in distal tubules. PMID:11014931

  16. Application of intact cell-based NFAT-β-lactamase reporter assay for Pasteurella multocida toxin-mediated activation of calcium signaling pathway

    PubMed Central

    Luo, Shuhong; Ho, Mengfei; Wilson, Brenda A.

    2009-01-01

    Pasteurella multocida toxin (PMT) stimulates and subsequently uncouples phospholipase C β1 (PLCβ1) signal transduction through its selective action on the alpha subunit of the Gq protein. Here, we describe the application of an NFAT-β-lactamase reporter assay as a functional readout for PMT-induced activation of the Gq-protein-coupled PLCβ1-IP3-Ca2+ signaling pathway. Use of the NFAT-β-lactamase reporter assay with a cell-permeable fluorogenic substrate provides high sensitivity due to the absence of endogenous β-lactamase activity in mammalian cells. This assay system was optimized for cell density, dose and time exposure of PMT stimulation. It is suited for quantitative characterization of PMT activity in mammalian cells and for use as a high-throughput screening method for PMT deletion and point mutants suitable for vaccine development. This method has application for diagnostic screening of clinical isolates of toxinogenic P. multocida. PMID:18190943

  17. Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements.

    PubMed

    Nehm, F; Mller-Meskamp, L; Klumbies, H; Leo, K

    2015-12-01

    A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 10(-5) g(H2O)/m(2)/d at 38?C, 90% relative humidity. PMID:26724091

  18. Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements

    NASA Astrophysics Data System (ADS)

    Nehm, F.; Mller-Meskamp, L.; Klumbies, H.; Leo, K.

    2015-12-01

    A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 10-5 g(H2O)/m2/d at 38 C, 90% relative humidity.

  19. 21 CFR 573.260 - Calcium silicate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium silicate. 573.260 Section 573.260 Food and... Listing § 573.260 Calcium silicate. Calcium silicate, including synthetic calcium silicate, may be safely used as an anticaking agent in animal feed, provided that the amount of calcium silicate does...

  20. 21 CFR 573.260 - Calcium silicate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Calcium silicate. 573.260 Section 573.260 Food and... Listing § 573.260 Calcium silicate. Calcium silicate, including synthetic calcium silicate, may be safely used as an anticaking agent in animal feed, provided that the amount of calcium silicate does...

  1. 21 CFR 184.1191 - Calcium carbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium carbonate. 184.1191 Section 184.1191 Food... GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg. No. 471-34-1) is prepared by... of calcium carbonate from calcium hydroxide in the “Carbonation process”; or (3) By precipitation...

  2. 21 CFR 184.1187 - Calcium alginate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium alginate. 184.1187 Section 184.1187 Food... GRAS § 184.1187 Calcium alginate. (a) Calcium alginate (CAS Reg. No. 9005-35-0) is the calcium salt of alginic acid, a natural polyuronide constituent of certain brown algae. Calcium alginate is prepared...

  3. 21 CFR 184.1191 - Calcium carbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium carbonate. 184.1191 Section 184.1191 Food... Specific Substances Affirmed as GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the...

  4. 21 CFR 573.260 - Calcium silicate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium silicate. 573.260 Section 573.260 Food and... Listing § 573.260 Calcium silicate. Calcium silicate, including synthetic calcium silicate, may be safely used as an anticaking agent in animal feed, provided that the amount of calcium silicate does...

  5. 21 CFR 184.1191 - Calcium carbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Calcium carbonate. 184.1191 Section 184.1191 Food... Specific Substances Affirmed as GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the...

  6. 21 CFR 184.1191 - Calcium carbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Calcium carbonate. 184.1191 Section 184.1191 Food... Specific Substances Affirmed as GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the...

  7. 21 CFR 573.260 - Calcium silicate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium silicate. 573.260 Section 573.260 Food and... Listing § 573.260 Calcium silicate. Calcium silicate, including synthetic calcium silicate, may be safely used as an anticaking agent in animal feed, provided that the amount of calcium silicate does...

  8. 21 CFR 184.1191 - Calcium carbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Calcium carbonate. 184.1191 Section 184.1191 Food... Specific Substances Affirmed as GRAS § 184.1191 Calcium carbonate. (a) Calcium carbonate (CaCO3, CAS Reg... soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the...

  9. 21 CFR 573.260 - Calcium silicate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium silicate. 573.260 Section 573.260 Food and... Listing § 573.260 Calcium silicate. Calcium silicate, including synthetic calcium silicate, may be safely used as an anticaking agent in animal feed, provided that the amount of calcium silicate does...

  10. Contributing factors in foliar uptake of dissolved inorganic nitrogen at leaf level.

    PubMed

    Wuyts, Karen; Adriaenssens, Sandy; Staelens, Jeroen; Wuytack, Tatiana; Van Wittenberghe, Shari; Boeckx, Pascal; Samson, Roeland; Verheyen, Kris

    2015-02-01

    We investigated the influence of leaf traits, rainwater chemistry, and pedospheric nitrogen (N) fertilisation on the aqueous uptake of inorganic N by physiologically active tree leaves. Leaves of juvenile silver birch and European beech trees, supplied with NH?NO? to the soil at rates from 0 to 200 kg N ha(-1)y(-1), were individually exposed to 100 ?l of artificial rainwater containing (15)NH?(+) or (15)NO?(-) at two concentration levels for one hour. In the next vegetative period, the experiment was repeated with NH?(+) at the highest concentration only. The N form and the N concentration in the applied rainwater and, to a lesser extent, the pedospheric N treatment and the leaf traits affected the aqueous foliar N uptake. The foliar uptake of NH?(+) by birch increased when leaves were more wettable. High leaf N concentration and leaf mass per area enhanced the foliar N uptake, and NO?(-) uptake in particular, by birch. Variation in the foliar N uptake by the beech trees could not be explained by the leaf traits considered. In the first experiment, N fertilisation stimulated the foliar N uptake in both species, which was on average 1.42-1.78 times higher at the highest soil N dose than at the zero dose. However, data variability was high and the effect was not appreciable in the second experiment. Our data suggest that next to rainwater chemistry (N form and concentration) also forest N status could play a role in the partitioning of N entering the ecosystem through the soil and the canopy. Models of canopy uptake of aqueous N at the leaf level should take account of leaf traits such as wettability and N concentration. PMID:25461099

  11. Atmospheric change alters foliar quality of host trees and performance of two outbreak insect species.

    PubMed

    Couture, John J; Meehan, Timothy D; Lindroth, Richard L

    2012-03-01

    This study examined the independent and interactive effects of elevated carbon dioxide (CO(2)) and ozone (O(3)) on the foliar quality of two deciduous trees species and the performance of two outbreak herbivore species. Trembling aspen (Populus tremuloides) and paper birch (Betula papyrifera) were grown at the Aspen FACE research site in northern Wisconsin, USA, under four combinations of ambient and elevated CO(2) and O(3). We measured the effects of elevated CO(2) and O(3) on aspen and birch phytochemistry and on gypsy moth (Lymantria dispar) and forest tent caterpillar (Malacosoma disstria) performance. Elevated CO(2) nominally affected foliar quality for both tree species. Elevated O(3) negatively affected aspen foliar quality, but only marginally influenced birch foliar quality. Elevated CO(2) slightly improved herbivore performance, while elevated O(3) decreased herbivore performance, and both responses were stronger on aspen than birch. Interestingly, elevated CO(2) largely offset decreased herbivore performance under elevated O(3). Nitrogen, lignin, and C:N were identified as having strong influences on herbivore performance when larvae were fed aspen, but no significant relationships were observed for insects fed birch. Our results support the notion that herbivore performance can be affected by atmospheric change through altered foliar quality, but how herbivores will respond will depend on interactions among CO(2), O(3), and tree species. An emergent finding from this study is that tree age and longevity of exposure to pollutants may influence the effects of elevated CO(2) and O(3) on plant-herbivore interactions, highlighting the need to continue long-term atmospheric change research. PMID:21971584

  12. Climatic limits on foliar growth during major droughts in the Southwestern U.S.A.

    USGS Publications Warehouse

    Weiss, Jeremy L.; Betancourt, Julio L.; Overpeck, Jonathan T.

    2012-01-01

    Pronounced droughts during the 1950s and 2000s in the Southwestern U.S.A. (SW) provide an opportunity to compare mesoscale ecosystem responses to anomalously dry conditions before and during the regional warming that started in the late 1970s. This year-round warming has produced fewer cool season freezes, losses in regional snowpack, an 8-10 day advance in spring onset, and hotter summers, all of which should affect vegetation differently across seasons and elevations. Here, we examine indices that represent climatic limits on foliar growth for both drought periods, and evaluate these indices for areas that experienced tree mortality during the 2000s drought. Relative to the 1950s drought, warmer conditions during the 2000s drought decreased the occurrence of temperatures too low for foliar growth at lower elevations in winter and higher elevations in summer. Higher vapor pressure deficits (VPDs) largely driven by warmer temperatures in the more recent drought were more limiting to foliar growth from spring through summer at lower and middle elevations. At many locations where tree mortality occurred during the 2000s drought, low-temperature constraints on foliar growth were extremely unlimiting, whereas VPD constraints were extremely limiting from early spring through late autumn. Our analysis shows that in physiographically complex regions like the SW, seasonality and elevational gradients are important for understanding vegetative responses to warming. It also suggests that continued warming will increase the degree to which VPD limits foliar growth during future droughts, and expand its reach to higher elevations and other seasons.

  13. Remote assessment of forest health in southern Arizona, USA: evidence for ozone-induced foliar injury.

    PubMed

    Diem, Jeremy E

    2002-03-01

    This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone exposure levels (SUM60 and W126) increased from 1982 to 1998 and were significantly correlated (r = 0.49 and 0.53, alpha = 0.05) with annual population totals in the Tucson area. Extensive masking of satellite images from 1972, 1986, and 1992 resulted in two optimal change detection areas, with one site, TVWMica, exposed mostly to the Tucson air pollution plume, while the other site, EMica, was more protected from Tucson-derived pollution. An overall increase in VI from 1972 to 1992 at both sites appears to have been caused by an increase in moisture availability. Larger foliar injury values in 1985 were associated with a smaller increase in VI (i.e., a smaller increase in green leaf biomass) from 1972 to 1986. From 1972 to 1986 and from 1986 to 1992, VI values at TV/WMica increased at a slower rate compared to those at EMica. The reduced increase in "green-up" may have been caused partially by ozone-induced foliar injury and resulting decreases in green leaf biomass. However, these spatial differences in VI values may have also been caused by a number of other factors. Results nevertheless reveal the strong possibility of distinct, topographically based, spatial variations in ozone-induced foliar injury within the Rincons. PMID:11830767

  14. Foliar response of black cherry (Prunus serotina) clones to ambient ozone exposure in central Pennsylvania.

    PubMed

    Lee, J C; Skelly, J M; Steiner, K C; Zhang, J W; Savage, J E

    1999-06-01

    During late summer of 1996 and 1997 we examined ozone-induced foliar injury in a plantation of 111 black cherry trees (ramets) comprising 15 clones originating from wild ortets growing in the Allegheny National Forest, Pennsylvania, and the Monongahela National Forest, West Virginia. The experimental plantation was a clonal seed orchard in Centre County, Pennsylvania, started in 1971 using ortet buds grafted onto seedling rootstocks of mixed origin. Clones differed significantly in severity of foliar injury symptoms (F=31.83, p<0.001). One clone (R-12) had significantly more foliar injury with >50% leaf area affected than other clones during both years. In contrast, clone R-14, which is from the same area in northcentral Pennsylvania as R-12, exhibited significantly less injury (LAA<6%). Although ambient O(3) concentrations were similar in both years, foliar injury was significantly greater (15.7%) in 1996 than in 1997 (9.9%). This is probably explained by lower stomatal conductance in 1997 caused by drier and hotter weather patterns in June and July of that year. Despite very different weather patterns and overall levels of injury in 1996 and 1997, mean clonal injury was significantly correlated between both years of assessment (r=0.92, p<0.001). Within tree crowns, foliage in lower and inner crown positions was significantly more injured than foliage in upper and exterior crown positions. There was no evidence of geographically based population differences in sensitivity to foliar O(3) injury. On the contrary, results demonstrate that wild genotypes of proximal geographic origin may differ greatly in sensitivity. PMID:15093074

  15. Habitat-specific differences in plasticity of foliar δ13C in temperate steppe grasses

    PubMed Central

    Liu, Yanjie; Zhang, Lirong; Niu, Haishan; Sun, Yue; Xu, Xingliang

    2014-01-01

    A decrease in foliar δ13C with increasing precipitation is a common tendency in steppe plants. However, the rate of decrease has been reported to differ between different species or populations. We here hypothesized that plant populations in the same habitat of temperate steppes may not differ in foliar δ13C response patterns to precipitation, but could differ in the levels of plasticity of foliar δ13C across different habitats. In order to test this hypothesis, we conducted controlled watering experiments in northeast China at five sites along a west–east transect at latitude 44°N, which show substantial interannual fluctuations and intra-annual changes in precipitation among them. In 2001, watering treatment (six levels, three replicates) was assigned to 18 plots at each site. The responses of foliar δ13C to precipitation (i.e., the sum of watering and rainfall) were determined in populations of several grass species that were common across all sites. Although similar linear regression slopes were observed for populations of different species growing at the same site, significantly different slopes were obtained for populations of the same species growing at different sites. Further, the slope of the line progressively decreased from Site I to Site V for all species in this study. These results suggest habitat-specific differences in plasticity of foliar δ13C in temperate steppe grasses. This indicates that species' δ13C response to precipitation is conservative at the same site due to their long-term acclimation, but the mechanism responsible behind this needs further investigations. PMID:25035804

  16. Erythroneura lawsoni abundance and feeding injury levels are influenced by foliar nutrient status in intensively managed American sycamore.

    SciTech Connect

    Coyle, David, Robert: Aubrey, Doug, Patric; Bentz, Jo-Ann

    2010-01-01

    Abstract 1 Abundance and feeding injury of the leafhopper Erythroneura lawsoni Robinson was measured in an intensively-managed American sycamore Platanus occidentalis L. plantation. Trees were planted in spring 2000 in a randomized complete block design, and received one of three annual treatments: (i) fertilization (120 kg N/ha/year); (ii) irrigation (3.0 cm/week); (iii) fertilization + irrigation; or (iv) control (no treatment). 2 Foliar nutrient concentrations were significantly influenced by the treatments because only sulphur and manganese levels were not statistically greater in trees receiving fertilization. 3 Over 116 000 E. lawsoni were captured on sticky traps during the study. Leafhopper abundance was highest on nonfertilized trees for the majority of the season, and was positively correlated with foliar nutrient concentrations. Significant temporal variation in E. lawsoni abundance occurred, suggesting five discrete generations in South Carolina. 4 Significant temporal variation occurred in E. lawsoni foliar injury levels, with the highest injury ratings occurring in late June and August. Foliar injury was negatively correlated with foliar nutrient content, and higher levels of injury occurred more frequently on nonfertilized trees. 5 The results obtained in the present study indicated that increased E. lawsoni abundance occurred on trees that did not receive fertilization. Nonfertilized trees experienced greater foliar injury, suggesting that lower foliar nutrient status may have led to increased levels of compensatory feeding.

  17. Extracellular calcium sensing and extracellular calcium signaling

    NASA Technical Reports Server (NTRS)

    Brown, E. M.; MacLeod, R. J.; O'Malley, B. W. (Principal Investigator)

    2001-01-01

    The cloning of a G protein-coupled extracellular Ca(2+) (Ca(o)(2+))-sensing receptor (CaR) has elucidated the molecular basis for many of the previously recognized effects of Ca(o)(2+) on tissues that maintain systemic Ca(o)(2+) homeostasis, especially parathyroid chief cells and several cells in the kidney. The availability of the cloned CaR enabled the development of DNA and antibody probes for identifying the CaR's mRNA and protein, respectively, within these and other tissues. It also permitted the identification of human diseases resulting from inactivating or activating mutations of the CaR gene and the subsequent generation of mice with targeted disruption of the CaR gene. The characteristic alterations in parathyroid and renal function in these patients and in the mice with "knockout" of the CaR gene have provided valuable information on the CaR's physiological roles in these tissues participating in mineral ion homeostasis. Nevertheless, relatively little is known about how the CaR regulates other tissues involved in systemic Ca(o)(2+) homeostasis, particularly bone and intestine. Moreover, there is evidence that additional Ca(o)(2+) sensors may exist in bone cells that mediate some or even all of the known effects of Ca(o)(2+) on these cells. Even more remains to be learned about the CaR's function in the rapidly growing list of cells that express it but are uninvolved in systemic Ca(o)(2+) metabolism. Available data suggest that the receptor serves numerous roles outside of systemic mineral ion homeostasis, ranging from the regulation of hormonal secretion and the activities of various ion channels to the longer term control of gene expression, programmed cell death (apoptosis), and cellular proliferation. In some cases, the CaR on these "nonhomeostatic" cells responds to local changes in Ca(o)(2+) taking place within compartments of the extracellular fluid (ECF) that communicate with the outside environment (e.g., the gastrointestinal tract). In others, localized changes in Ca(o)(2+) within the ECF can originate from several mechanisms, including fluxes of calcium ions into or out of cellular or extracellular stores or across epithelium that absorb or secrete Ca(2+). In any event, the CaR and other receptors/sensors for Ca(o)(2+) and probably for other extracellular ions represent versatile regulators of numerous cellular functions and may serve as important therapeutic targets.

  18. Custom-made modification of a commercial confocal microscope to photolyze caged compounds using the conventional illumination module and its application to the observation of Inositol 1,4,5-trisphosphate-mediated calcium signals

    NASA Astrophysics Data System (ADS)

    Sigaut, Lorena; Barella, Mariano; Espada, Roco; Ponce, Mara Laura; Dawson, Silvina Ponce

    2011-06-01

    The flash photolysis of ``caged'' compounds is a powerful experimental technique for producing rapid changes in concentrations of bioactive signaling molecules. These caged compounds are inactive and become active when illuminated with ultraviolet light. This paper describes an inexpensive adaptation of an Olympus confocal microscope that uses as source of ultraviolet light the mercury lamp that comes with the microscope for conventional fluorescence microscopy. The ultraviolet illumination from the lamp (350 - 400 nm) enters through an optical fiber that is coupled to a nonconventional port of the microscope. The modification allows to perform the photolysis of caged compounds over wide areas (~200 ?m) and obtain confocal fluorescence images simultaneously. By controlling the ultraviolet illumination exposure time and intensity it is possible to regulate the amount of photolyzed compounds. In the paper we characterize the properties of the system and show its capabilities with experiments done in aqueous solution and in Xenopus Laevis oocytes. The latter demonstrate its applicability for the study of Inositol 1,4,5-trisphosphate-mediated intracellular calcium signals.

  19. 21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Calcium pantothenate, calcium chloride double salt... Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate may be safely used in foods for...

  20. 21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Calcium pantothenate, calcium chloride double salt... FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate...

  1. 21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Calcium pantothenate, calcium chloride double salt... FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate...

  2. 21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium pantothenate, calcium chloride double salt... FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate...

  3. 21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Calcium pantothenate, calcium chloride double salt... FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate...

  4. Calcium signal compartmentalization.

    PubMed

    Petersen, Ole H

    2002-01-01

    Cytosolic calcium signals are produced by suddenly increasing the concentration of free calcium ions (Ca2+). This can occur by opening channels permeable to Ca2+ either in the surface cell membrane or in the membranes of intracellular organelles containing high Ca2+ concentrations. Ca2+ signals can control several different processes, even in the same cell. In pancreatic acinar cells, for example, Ca2+ signals do not only control the normal secretion of digestive enzymes, but can also activate autodigestion and programmed cell death. Recent technical advances have shown that different patterns of Ca2+ signals can be created, in space and time, which allow specific cellular responses to be elicited. The mechanisms responsible for Ca2+ signal compartmentalization are now largely known and will be described on the basis of recent studies of Ca2+ transport pathways and their regulation in pancreatic acinar cells. It turns out that the Ca2+ handling as well as the structural characteristics of the endoplasmic reticulum (ER) and the mitochondria are of particular importance. Using a variety of Ca(2+)-sensitive fluorescent probes placed in different sub-cellular compartments in combination with local uncaging of caged Ca2+, many new insights into Ca2+ signal generation, compartmentalization and termination have recently been obtained. PMID:12415734

  5. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA.

    PubMed

    Minocha, Rakesh; Turlapati, Swathi A; Long, Stephanie; McDowell, William H; Minocha, Subhash C

    2015-08-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha(-1) year(-1)) and high N (HN, 150 kg NH4NO3 ha(-1) year(-1)) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments until 2002. By 2005, several of these effects on N metabolites disappeared for HN, and by 2008 they were mostly observed for LN plot. A significant decline in foliar Ca and P was observed mostly with HN for a few years until 2005. However, sapwood data actually showed an increase in Ca, Mg and Mn and no change in PAs in the HN plot for 2008, while AAs data revealed trends that were generally similar to foliage for 2008. Concomitant with these changes, mortality data revealed a large number of dead trees in HN pine plots by 2002; the mortality rate started to decline by 2005. Oak trees in the hardwood plot did not exhibit any major changes in PAs, AAs, nutrients and mortality rate with LN treatment, indicating that oak trees were able to tolerate the yearly doses of 50 kg NH4NO3 ha(-1) year(-1). However, HN trees suffered from physiological and nutritional stress along with increased mortality in 2008. In this case also, foliar data were supported by the sapwood data. Overall, both low and high N applications resulted in greater physiological stress to the pine trees than the oaks. In general, the time course of changes in metabolic data are in agreement with the published reports on changes in soil chemistry and microbial community structure, rates of soil carbon sequestration and production of woody biomass for this chronic N study. This correspondence of selected metabolites with other measures of forest functions suggests that the metabolite analyses are useful for long-term monitoring of the health of forest trees. PMID:26116927

  6. Injectable bioactive calcium-magnesium phosphate cement for bone regeneration.

    PubMed

    Wu, Fan; Su, Jiacan; Wei, Jie; Guo, Han; Liu, Changsheng

    2008-12-01

    Novel injectable and degradable calcium-magnesium phosphate cement (CMPC) with rapid-setting characteristic was developed by the introduction of magnesium phosphate cement (MPC) into calcium phosphate cement (CPC). The calcium-magnesium phosphate cement prepared under the optimum P/L ratio exhibited good injectability and desired workability. It could set within 10 min at 37 degrees C in 100% relative humidity and the compressive strength could reach 47 MPa after setting for 48 h, indicating that the prepared cement has relatively high initial mechanical strength. The results of in vitro degradation experiments demonstrated the good degradability of the injectable CMPC, and its degradation rate occurred significantly faster than that of pure CPC in simulated body fluid (SBF) solution. It can be concluded that the novel injectable calcium-magnesium phosphate cement is highly promising for a wide variety of clinical applications, especially for the development of minimally invasive techniques. PMID:19029607

  7. Calcium in the regulation of gravitropism by light

    NASA Technical Reports Server (NTRS)

    Perdue, D. O.; LaFavre, A. K.; Leopold, A. C.

    1988-01-01

    The red light requirement for positive gravitropism in roots of corn (Zea mays cv "Merit") provides an entry for examining the participation of calcium in gravitropism. Applications of calcium chelators inhibit the light response. Calcium channel blockers (verapamil, lanthanum) can also inhibit the light response, and a calcium ionophore, A23187, can substitute for light. One can substitute for red light by treatments which have elsewhere been shown to trigger Ca2+ influx into the cytosol, e.g. heat or cold shock. Agents which are known to be agonists of the phosphatidylinositol second messenger system (serotonin, 2,4-dichlorophenoxyacetic acid, deoxycholate) can each partially substitute for the red light, and Li+ can inhibit the light effect. These experiments suggest that the induction of positive gravitropism by red light involves a rise in cytoplasmic Ca2+ concentration, and that a contribution to this end may be made by the phosphatidylinositol second messenger system.

  8. Control of Intracellular Calcium Signaling as a Neuroprotective Strategy

    PubMed Central

    Duncan, R. Scott; Goad, Daryl L.; Grillo, Michael A.; Kaja, Simon; Payne, Andrew J.; Koulen, Peter

    2010-01-01

    Both acute and chronic degenerative diseases of the nervous system reduce the viability and function of neurons through changes in intracellular calcium signaling. In particular, pathological increases in the intracellular calcium concentration promote such pathogenesis. Disease involvement of numerous regulators of intracellular calcium signaling located on the plasma membrane and intracellular organelles has been documented. Diverse groups of chemical compounds targeting ion channels, G-protein coupled receptors, pumps and enzymes have been identified as potential neuroprotectants. The present review summarizes the discovery, mechanisms and biological activity of neuroprotective molecules targeting proteins that control intracellular calcium signaling to preserve or restore structure and function of the nervous system. Disease relevance, clinical applications and new technologies for the identification of such molecules are being discussed. PMID:20335972

  9. Calcium Isotope Systematics During Development of the Domestic Chicken (Gallus gallus)

    NASA Astrophysics Data System (ADS)

    Wheatley, P. V.

    2003-12-01

    Calcium isotope distributions have been recognized as showing systematic and predictable fractionation in nature. However, most of the observed calcium isotope fractionation to date is due to biological processes. The presence of abundant amounts of calcium in mineralized tissues makes the isotopic system of calcium particularly valuable in biological and paleobiological questions involving biomineralization. In order to apply calcium isotope systematics to paleobiological questions the changes in the calcium isotope signatures of mineralized tissue in modern animals should be studied. My study observed the domestic chicken (Gallus gallus) through embryologic ontogeny. This was accomplished by obtaining fertilized eggs staged in a growth series from day 12 to day 20. The eggs were dissected and shell, embryonic bone, albumen, and yolk were analyzed in order to characterize the calcium isotopic composition of the individual components over the course of the growth series. Several systematic changes in the isotopic signatures of various tissues were observed during the course of the development of the embryos. In general, mineralization in biological systems preferentially partitions the lighter isotopes of calcium into hard parts. As a result of this fractionation during mineralization, partitioning of light isotopes of calcium into the mineralized tissues may result in residual tissues being enriched in the heavier isotopes as ontogeny progresses. Better understanding of the behavior of calcium in modern biological systems will improve its application to fossils and expand the number of paleobiological and evolutionary questions that can be addressed using calcium isotopic data.

  10. Calcium transporters: From fields to the table

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium transporters regulate calcium fluxes within cells. Plants, like all organisms, contain channels, pumps, and exchangers to carefully modulate intracellular calcium levels. This review presents a summary of the recent advances in cloning and characterizing of these transporters and highlight...

  11. Calcium Orthophosphates as Bioceramics: State of the Art

    PubMed Central

    Dorozhkin, Sergey V.

    2010-01-01

    In the late 1960s, much interest was raised in regard to biomedical applications of various ceramic materials. A little bit later, such materials were named bioceramics. This review is limited to bioceramics prepared from calcium orthophosphates only, which belong to the categories of bioactive and bioresorbable compounds. There have been a number of important advances in this field during the past 30–40 years. Namely, by structural and compositional control, it became possible to choose whether calcium orthophosphate bioceramics were biologically stable once incorporated within the skeletal structure or whether they were resorbed over time. At the turn of the millennium, a new concept of calcium orthophosphate bioceramics—which is able to promote regeneration of bones—was developed. Presently, calcium orthophosphate bioceramics are available in the form of particulates, blocks, cements, coatings, customized designs for specific applications and as injectable composites in a polymer carrier. Current biomedical applications include artificial replacements for hips, knees, teeth, tendons and ligaments, as well as repair for periodontal disease, maxillofacial reconstruction, augmentation and stabilization of the jawbone, spinal fusion and bone fillers after tumor surgery. Exploratory studies demonstrate potential applications of calcium orthophosphate bioceramics as scaffolds, drug delivery systems, as well as carriers of growth factors, bioactive peptides and/or various types of cells for tissue engineering purposes. PMID:24955932

  12. Major Minerals - Calcium, Magnesium, Phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium, magnesium and phosphorus are essential elements critically important for the function of the musculoskeletal system, including the formation and transduction of energy and the maintenance of healthy bone. The major calcium concern for physically active healthy middle-aged adults is to consu...

  13. Calcium Flickers Steer Cell Migration

    PubMed Central

    Wei, Chaoliang; Wang, Xianhua; Chen, Min; Ouyang, Kunfu; Song, Long-Sheng; Cheng, Heping

    2012-01-01

    Directional movement is a property common to all cell types during development and is critical to tissue remodelling and regeneration after damage1–3. In migrating cells, calcium plays a multifunctional role in directional sensing, cytoskeleton redistribution, traction force generation, and relocation of focal adhesions1, 4–7. Here we visualise, for the first time, high-calcium microdomains (“calcium flickers”), and their patterned activation in migrating fibroblasts. Calcium flicker activity is dually coupled to membrane tension (via TRPM7, a stretch-activated Ca2+-permeant channel of the transient receptor potential superfamily8) and chemoattractant signal transduction (via type 2 inositol 1,4,5-trisphosphate receptors). Interestingly, calcium flickers are most active at the leading lamella of migrating cells, displaying a 4:1 front-to-rear polarisation opposite to the global calcium gradient6. When exposed to a PDGF gradient perpendicular to cell movement, asymmetric calcium flicker activity develops across the lamella and promotes the turning of migrating fibroblasts. These findings illustrate how the exquisite spatiotemporal organisation of calcium microdomains can orchestrate complex cellular processes such as cell migration. PMID:19118385

  14. An Improved Calcium Flame Test.

    ERIC Educational Resources Information Center

    Pearson, Robert S.

    1985-01-01

    Indicates that the true red color of calcium can be obtained (using the procedure described by Sorm and Logowski) if the calcium ion solution is mixed with an equal volume of saturated ammonium bromide solution. Suggestions for flame tests of other elements are also noted. (JN)

  15. Calcium Intake: A Lifelong Proposition.

    ERIC Educational Resources Information Center

    Amschler, Denise H.

    1985-01-01

    This article reviews the current problem of low calcium intake in the United States among all age groups, the role of calcium in the formation and maintenance of bone mass, and major factors influencing absorption. Osteoporosis is discussed, and current recommendations for Recommended Dietary allowance are provided. (Author/MT)

  16. Calcium requirements for the athlete.

    PubMed

    Kunstel, Katherine

    2005-08-01

    There is oftentimes a notion of "the more, the better" with regard to vitamin and mineral intake among individuals, and especially among athletes. Although adequate calcium intake is necessary to promote bone health and prevent osteoporosis, increased physical activity alone does not necessarily demand an increased intake of dietary calcium or other micronutrients. Athletes may lose calcium via sweat, in which case replenishment is advocated either via dietary intake of calcium-rich foods or a commercial calcium supplement. The important message to athletes is to consume a diet adequate in energy, protein, fat, vitamins, minerals, and fluids to support the physical demands and replenish the physiologic losses incurred with physical training. PMID:16004829

  17. Foliar d13C within a temperate deciduous forest: spatial, temporal, and species sources of variation

    SciTech Connect

    Garten Jr, Charles T; TaylorJr, G. E.

    1992-04-01

    Foliar {sup 13}C-abundance ({delta}{sup 13}C) was analyzed in the dominant trees of a temperate deciduous forest in east Tennessee (Walker Branch Watershed) to investigate the variation in foliar {delta}{sup 13}C as a function of time (within-year and between years), space (canopy height, watershed topography and habitat) and species (deciduous and coniferous taxa). Various hypotheses were tested by analyzing (i) samples collected from the field during the growing season and (ii) foliar tissues maintained in an archived collection. The {delta}{sup 13}C-value for leaves from the tops of trees was 2 to 3%. more positive than for leaves sampled at lower heights in the canopy. Quercus prinus leaves sampled just prior to autumn leaf fall had significantly more negative {delta}{sup 13}C-values than those sampled during midsummer. On the more xeric ridges, needles of Pinus spp. had more positive {delta}{sup 13}C-values than leaves from deciduous species. Foliar {delta}{sup 13}C-values differed significantly as a function of topography. Deciduous leaves from xeric sites (ridges and slopes) had more positive {delta}{sup 13}C-values than those from mesic (riparian and cove) environments. On the more xeric sites, foliar {delta}{sup 13}C was significantly more positive in 1988 (a dry year) relative to that in 1989 (a year with above-normal precipitation). In contrast, leaf {delta}{sup 13}C in trees from mesic valley bottoms did not differ significantly among years with disparate precipitation. Patterns in foliar {delta}{sup 13}C indicated a higher ratio of net CO{sub 2} assimilation to transpiration (A/E) for trees in more xeric versus mesic habitats, and for trees in xeric habitats during years of drought versus years of normal precipitation. However, A/E (units of mmol CO{sub 2} fixed/mol H{sub 2}O transpired) calculated on the basis of {delta}{sup 13}C-values for leaves from the more xeric sites was higher in a wet year (6.6 {+-} 1.2) versus a dry year (3.4 {+-} 0.4). This difference was attributed to higher transpiration (and therefore lower A/E) in the year with lower relative humidity and higher average daily temperature. The calculated A/E values for the forest in 1988-89, based on {delta}{sup 13}C, were within {+-}55% of estimates made over a 17 day period at this site in 1984 using micrometeorological methods.

  18. Calcium-deficiency assessment and biomarker identification by an integrated urinary metabonomics analysis

    PubMed Central

    2013-01-01

    Background Calcium deficiency is a global public-health problem. Although the initial stage of calcium deficiency can lead to metabolic alterations or potential pathological changes, calcium deficiency is difficult to diagnose accurately. Moreover, the details of the molecular mechanism of calcium deficiency remain somewhat elusive. To accurately assess and provide appropriate nutritional intervention, we carried out a global analysis of metabolic alterations in response to calcium deficiency. Methods The metabolic alterations associated with calcium deficiency were first investigated in a rat model, using urinary metabonomics based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry and multivariate statistical analysis. Correlations between dietary calcium intake and the biomarkers identified from the rat model were further analyzed to confirm the potential application of these biomarkers in humans. Results Urinary metabolic-profiling analysis could preliminarily distinguish between calcium-deficient and non-deficient rats after a 2-week low-calcium diet. We established an integrated metabonomics strategy for identifying reliable biomarkers of calcium deficiency using a time-course analysis of discriminating metabolites in a low-calcium diet experiment, repeating the low-calcium diet experiment and performing a calcium-supplement experiment. In total, 27 biomarkers were identified, including glycine, oxoglutaric acid, pyrophosphoric acid, sebacic acid, pseudouridine, indoxyl sulfate, taurine, and phenylacetylglycine. The integrated urinary metabonomics analysis, which combined biomarkers with regular trends of change (types A, B, and C), could accurately assess calcium-deficient rats at different stages and clarify the dynamic pathophysiological changes and molecular mechanism of calcium deficiency in detail. Significant correlations between calcium intake and two biomarkers, pseudouridine (Pearson correlation, r = 0.53, P = 0.0001) and citrate (Pearson correlation, r = -0.43, P = 0.001), were further confirmed in 70 women. Conclusions To our knowledge, this is the first report of reliable biomarkers of calcium deficiency, which were identified using an integrated strategy. The identified biomarkers give new insights into the pathophysiological changes and molecular mechanisms of calcium deficiency. The correlations between calcium intake and two of the biomarkers provide a rationale or potential for further assessment and elucidation of the metabolic responses of calcium deficiency in humans. PMID:23537001

  19. Diffusion in calcium oxide/calcium sulfate pellets

    SciTech Connect

    Chang, K.L.

    1981-10-01

    Diffusion rates in calcium oxide pellets after partial conversion to calcium sulfate were measured. A Wicke-Kallenbach type diffusion cell operated in the pulse-response mode was used to measure effective diffusivity. Cylindrical calcium oxide pellets were formed from the powder using pelletizing pressures of 10,000, 20,000 and 30,000 psi. The pellets were reacted at 325, 500 and 600/sup 0/C with sulfur dioxide and oxygen to form calcium sulfate. The volume of calcium sulfate is 2.7 times that of calcium oxide, so partial pore closure occurs. The diffusivity was measured in the original pellet and in pellets partially reacted to several different conversion levels. The effective diffusivity decreases as conversion decreases and is roughly inversely proportional to pellet porosity squared for low conversions. However, the porosity and diffusion rate do not become zero when the reaction rate approaches zero. Pore closure is, therefore, not the mechanism which limits the ultimate conversion. A large diffusion resistance through the calcium sulfate product layer probably causes the reaction to stop before total conversion. The final conversion obtainable increases as reaction temperature increases and decreases as pelletizing pressure increases.

  20. Calcium signaling properties of a thyrotroph cell line, mouse TαT1 cells.

    PubMed

    Tomić, Melanija; Bargi-Souza, Paula; Leiva-Salcedo, Elias; Nunes, Maria Tereza; Stojilkovic, Stanko S

    2015-12-01

    TαT1 cells are mouse thyrotroph cell line frequently used for studies on thyroid-stimulating hormone beta subunit gene expression and other cellular functions. Here we have characterized calcium-signaling pathways in TαT1 cells, an issue not previously addressed in these cells and incompletely described in native thyrotrophs. TαT1 cells are excitable and fire action potentials spontaneously and in response to application of thyrotropin-releasing hormone (TRH), the native hypothalamic agonist for thyrotrophs. Spontaneous electrical activity is coupled to small amplitude fluctuations in intracellular calcium, whereas TRH stimulates both calcium mobilization from intracellular pools and calcium influx. Non-receptor-mediated depletion of intracellular pool also leads to a prominent facilitation of calcium influx. Both receptor and non-receptor stimulated calcium influx is substantially attenuated but not completely abolished by inhibition of voltage-gated calcium channels, suggesting that depletion of intracellular calcium pool in these cells provides a signal for both voltage-independent and -dependent calcium influx, the latter by facilitating the pacemaking activity. These cells also express purinergic P2Y1 receptors and their activation by extracellular ATP mimics TRH action on calcium mobilization and influx. The thyroid hormone triiodothyronine prolongs duration of TRH-induced calcium spikes during 30-min exposure. These data indicate that TαT1 cells are capable of responding to natively feed-forward TRH signaling and intrapituitary ATP signaling with acute calcium mobilization and sustained calcium influx. Amplification of TRH-induced calcium signaling by triiodothyronine further suggests the existence of a pathway for positive feedback effects of thyroid hormones probably in a non-genomic manner. PMID:26453278

  1. Foliar Reflectance and Fluorescence Responses for Plants Under Nitrogen Stress Determined with Active and Passive Systems

    NASA Technical Reports Server (NTRS)

    Middleton, E. M.; McMurtrey, J. E.; Campbell, P. K. Entcheva; Corp, L. A.; Butcher, L. M.; Chappelle, E. W.

    2003-01-01

    Vegetation productivity is driven by nitrogen (N) availability in soils. Both excessive and low soil N induce physiological changes in plant foliage. In 2001, we examined the use of spectral fluorescence and reflectance measurements to discriminate among plants provided different N fertilizer application rates: 20%, 50%, 100% and 150% of optimal N levels. A suite of optical, fluorescence, and biophysical measurements were collected on leaves from field grown corn (Zea mays L.) and soybean plants (Glycine max L.) grown in pots (greenhouse + ambient sunlight daily). Three types of steady state laser-induced fluorescence measurements were made on adaxial and abaxial surfaces: 1) fluorescence images in four 10 nm bands (blue, green, red, far-red) resulting from broad irradiance excitation; 2) emission spectra (5 nm resolution) produced by excitation at single wavelengths (280,380 or 360, and 532 nm); and 3) excitation spectra (2 nm resolution), with emission wavelengths fixed at wavelengths centered on selected solar Fraunhofer lines (532,607,677 and 745 nm). Two complementary sets of high resolution (less than 2 nm) optical spectra were acquired for both adaxial and abaxial leaf surfaces: 1) optical properties (350-2500 nm) for reflectance, transmittance, and absorptance; and 2) reflectance spectra (500-1000 nm) acquired with and without a short pass filter at 665 nm to determine the fluorescence contribution to apparent reflectance in the 650-750 spectrum, especially at the 685 and 740 nm chlorophyll fluorescence (ChIF) peaks. The strongest relationships between foliar chemistry and optical properties were demonstrated for C/N content and two optical parameters associated with the red edge inflection point. Select optical properties and ChIF parameters were highly correlated for both species. A significant contribution of ChIF to apparent reflectance was observed, averaging 10-25% at 685 nm and 2 - 6% at 740 nm over all N treatments. Discrimination of N treatment groups was possible with specific fluorescence band ratios (e.g., F740/F525 obtained with 380EX). From all measurements assessing fluorescence, higher ChIF and blue/green emissions were measured from the abaxial leaf surfaces; Abaxial surfaces also produced higher reflectances in the 400-800 nm spectrum. Fluorescence information collected in Fraunhofer regions located on the shoulders of ChIF features compared favorably with peak emissions. This supports the potential capability of a future space-born interferometer sensor to capture plant canopy fluorescence.

  2. [Effects of snow cover on water soluble and organic solvent soluble components during foliar litter decomposition in an alpine forest].

    PubMed

    Xu, Li-Ya; Yang, Wan-Qin; Li, Han; Ni, Xiang-Yin; He, Jie; Wu, Fu-Zhong

    2014-11-01

    Seasonal snow cover may change the characteristics of freezing, leaching and freeze-thaw cycles in the scenario of climate change, and then play important roles in the dynamics of water soluble and organic solvent soluble components during foliar litter decomposition in the alpine forest. Therefore, a field litterbag experiment was conducted in an alpine forest in western Sichuan, China. The foliar litterbags of typical tree species (birch, cypress, larch and fir) and shrub species (willow and azalea) were placed on the forest floor under different snow cover thickness (deep snow, medium snow, thin snow and no snow). The litterbags were sampled at snow formation stage, snow cover stage and snow melting stage in winter. The results showed that the content of water soluble components from six foliar litters decreased at snow formation stage and snow melting stage, but increased at snow cover stage as litter decomposition proceeded in the winter. Besides the content of organic solvent soluble components from azalea foliar litter increased at snow cover stage, the content of organic solvent soluble components from the other five foliar litters kept a continue decreasing tendency in the winter. Compared with the content of organic solvent soluble components, the content of water soluble components was affected more strongly by snow cover thickness, especially at snow formation stage and snow cover stage. Compared with the thicker snow covers, the thin snow cover promoted the decrease of water soluble component contents from willow and azalea foliar litter and restrain the decrease of water soluble component content from cypress foliar litter. Few changes in the content of water soluble components from birch, fir and larch foliar litter were observed under the different thicknesses of snow cover. The results suggested that the effects of snow cover on the contents of water soluble and organic solvent soluble components during litter decomposition would be controlled by litter quality. PMID:25898600

  3. A Review Paper on Biomimetic Calcium Phosphate Coatings

    PubMed Central

    Lin, X.; de Groot, K.; Wang, D.; Hu, Q.; Wismeijer, D.; Liu, Y.

    2015-01-01

    Biomimetic calcium phosphate coatings have been developed for bone regeneration and repair because of their biocompatibility, osteoconductivity, and easy preparation. They can be rendered osteoinductive by incorporating an osteogenic agent, such as bone morphogenetic protein 2 (BMP-2), into the crystalline lattice work in physiological situations. The biomimetic calcium phosphate coating enables a controlled, slow and local release of BMP-2 when it undergoes cell mediated coating degradation induced by multinuclear cells, such as osteoclasts and foreign body giant cells, which mimics a physiologically similar release mode, to achieve sustained ectopic or orthotopic bone formation. Therefore, biomimetic calcium phosphate coatings are considered to be a promising delivery vehicle for osteogenic agents. In this review, we present an overview of biomimetic calcium phosphate coatings including their preparation techniques, physico-chemical properties, potential as drug carrier, and their pre-clinical application both in ectopic and orthotopic animal models. We briefly review some features of hydroxyapatite coatings and their clinical applications to gain insight into the clinical applications of biomimetic calcium phosphate coatings in the near future. PMID:25893016

  4. Phytotoxic activity of foliar volatiles and essential oils of Calamintha nepeta (L.) Savi.

    PubMed

    Araniti, Fabrizio; Lupini, Antonio; Sorgon, Agostino; Statti, Giancarlo Antonio; Abenavoli, Maria Rosa

    2013-01-01

    Foliar volatiles and essential oils of Calamintha nepeta (L.) Savi, a Mediterranean plant species belonging to the Labiatae family, were investigated for their phytotoxic activities on seed germination and root growth of crops (Lactuca sativa L. and Raphanus sativus L.) and weed species (Lolium perenne L. and Amaranthus retroflexus L.). Foliar volatiles of C. nepeta (L.) Savi strongly inhibited both germination and root growth of lettuce, and its essential oils, especially at 125, 250 and 500?L/L, inhibited both processes in lettuce, radish and A. retroflexus L. species, while displaying a little effect on L. perenne L. By GC-MS, 28 chemicals were identified: 17 monoterpenes, 8 sesquiterpenes, 1 diterpene and 2 miscellaneous. Pulegone was the main constituent of the C. nepeta (L.) Savi essential oils. The terpenic components of essentials oils were probably responsible for the phytotoxic activities. PMID:23216166

  5. Role of Stomata in Plant Innate Immunity and Foliar Bacterial Diseases

    PubMed Central

    Melotto, Maeli; Underwood, William; He, Sheng Yang

    2008-01-01

    Pathogen entry into host tissue is a critical first step in causing infection. For foliar bacterial plant pathogens, natural surface openings, such as stomata, are important entry sites. Historically, these surface openings have been considered as passive portals of entry for plant pathogenic bacteria. However, recent studies have shown that stomata can play an active role in limiting bacterial invasion as part of the plant innate immune system. As counter-defense, the plant pathogen Pseudomonas syringae pv. tomato DC3000 uses the virulence factor coronatine to actively open stomata. In nature, many foliar bacterial disease outbreaks require high humidity, rain, or storms, which could promote stomatal opening and/or bypass stomatal defense by creating wounds as alternative entry sites. Further studies on microbial and environmental regulation of stomatal closure and opening could fill gaps in our understanding of bacterial pathogenesis, disease epidemiology, and microbiology of the phyllosphere. PMID:18422426

  6. Water relations in the interaction of foliar bacterial pathogens with plants.

    PubMed

    Beattie, Gwyn A

    2011-01-01

    This review examines the many ways in which water influences the relations between foliar bacterial pathogens and plants. As a limited resource in aerial plant tissues, water is subject to manipulation by both plants and pathogens. A model is emerging that suggests that plants actively promote localized desiccation at the infection site and thus restrict pathogen growth as one component of defense. Similarly, many foliar pathogens manipulate water relations as one component of pathogenesis. Nonvascular pathogens do this using effectors and other molecules to alter hormonal responses and enhance intercellular watersoaking, whereas vascular pathogens use many mechanisms to cause wilt. Because of water limitations on phyllosphere surfaces, bacterial colonists, including pathogens, benefit from the protective effects of cellular aggregation, synthesis of hygroscopic polymers, and uptake and production of osmoprotective compounds. Moreover, these bacteria employ tactics for scavenging and distributing water to overcome water-driven barriers to nutrient acquisition, movement, and signal exchange on plant surfaces. PMID:21438680

  7. Intercellular spiral waves of calcium.

    PubMed

    Wilkins, M; Sneyd, J

    1998-04-01

    Intercellular calcium waves have been observed in a large number of cell types, and are known to result from a variety of stimuli, including mechanical or hormonal stimulation. Recently, spiral intercellular waves of calcium have been observed in slices of hippocampal tissue. We use an existing model to study the properties of spiral intercellular calcium waves. Although intercellular spiral waves are well known in the context of cardiac muscle, due to the small value of the calcium diffusion coefficient intercellular calcium waves have fundamentally different properties. We show that homogenisation techniques give a good estimate for the plane wave speed, but do not describe spiral behaviour well. Using an expression for the effective diffusion coefficient we estimate the intercellular calcium permeability in liver. For the bistable equation, we derive an analytic estimate for the value of the intercellular permeability at which wave propagation fails. In the calcium wave model, we show numerically that the spiral period is first a decreasing, then an increasing, function of the intercellular permeability. We hypothesise that this is because the curvature of the spiral core is unimportant at low permeability, the period being approximately set instead by the speed of a plane wave along a line of coupled cells in one dimension. PMID:9631570

  8. Effects of ozone on morphogenesis of the foliar embryos of bryophyllum calycinum Salisb

    SciTech Connect

    Rier, J.P.; Phillips, G. )

    1990-01-01

    Explants from three different ages, including the foliar embryo of ozonated and non-ozonated marginal leaf tissue from Bryophyllum calycinum were cultured on modified formulations of Murashige and Skoog's medium. Kinetin 2,4-D and IAA were added to the media individually or in combination. The development of the embryos was affected by tissue age, media composition and prior exposure to ozone. The production of callus, shoots, roots and anthocyanin were all in response to different sets of culture conditions.

  9. Foliar anatomical and morphological variation in Nothofagus pumilio seedlings under controlled irradiance and soil moisture levels.

    PubMed

    Ivancich, Horacio S; Lencinas, Mara V; Pastur, Guillermo J Martnez; Esteban, Rosina M Soler; Hernndez, Luis; Lindstrom, Ivone

    2012-05-01

    Foliar anatomy and morphology are strongly related to physiological performance; therefore, phenotypic plasticity in leaves to variations in environmental conditions, such as irradiance and soil moisture availability, can be related to growth rate and survivorship, mainly during critical growth phases, such as establishment. The aim of this work was to analyze changes in the foliar internal anatomy (tissue proportions and cell dimensions) and external morphology (leaf length, width and area) of Nothofagus pumilio (Poepp. et Endl.) Krasser seedlings growing in a greenhouse under controlled irradiance (three levels) and soil moisture (two levels) during one growing season (measured three times), and to relate them to physiological traits. Three irradiance levels (4, 26 and 64% of the natural incident light) and two soil moisture levels (40 and 80% soil capacity) were evaluated during November, January and March. Internal foliar anatomy of seedlings was analyzed using digital photographs of histological cuttings, while leaf gross morphology was measured using digital calipers and image analysis software. Most internal anatomical variables presented significant differences under different irradiance levels during the growing season, but differences were not detected between soil moisture levels. Palisade parenchyma was the tissue most sensitive to irradiance levels, and high irradiance levels (64% natural incident light) produced greater values in most of the internal anatomical variables than lower irradiance levels (4-24% natural incident light). Complementarily, larger leaves were observed in medium and low irradiance levels, as well as under low soil moisture levels (40% soil capacity). The relationship of main results with some eco-physiological traits was discussed. Foliar internal anatomical and external morphological plasticity allows quick acclimation of seedlings to environmental changes (e.g., during harvesting). These results can be used to propose new forest practices that consider soil moisture and light availability changes to maintain high physiological performance of seedlings. PMID:22499597

  10. Calcium signals in olfactory neurons.

    PubMed

    Tareilus, E; Noé, J; Breer, H

    1995-11-01

    Laser scanning confocal microscopy in combination with the fluorescent calcium indicators Fluo-3 and Fura-Red was employed to estimate the intracellular concentration of free calcium ions in individual olfactory receptor neurons and to monitor temporal and spatial changes in the Ca(2+)-level upon stimulation. The chemosensory cells responded to odorants with a significant increase in the calcium concentration, preferentially in the dendritic knob. Applying various stimulation paradigma, it was found that in a population of isolated cells, subsets of receptor neurons display distinct patterns of responsiveness. PMID:7488645

  11. Elevational and seasonal variation in the foliar quality and arthropod community of Acer pensylvanicum.

    PubMed

    Zehnder, Caralyn B; Stodola, Kirk W; Joyce, Blake L; Egetter, David; Cooper, Robert J; Hunter, Mark D

    2009-08-01

    Elevational gradients provide natural experiments for examining how variation in abiotic forces such as nutrient mineralization rates, risk of photodamge, temperature, and precipitation influence plant-insect interactions. At the Coweeta LTER site in the Southern Appalachian Mountains, we examined spatial and temporal variation in striped maple, Acer pensylvanicum, foliar quality and associated patterns in the arthropod community. Variation in herbivore densities was associated more strongly with seasonal variation in plant quality than with spatial variation in quality among three sampling sites. Leaf chewer, but not phloem feeder or arthropod predator, densities increased with elevation. Foliar quality, by our measures, decreased throughout the growing season, with decreases in nitrogen concentrations and increases in lignin concentrations. Foliar quality varied among the three sites but not systematically along the elevational gradient. We conclude that, in this system, temporal heterogeneity in plant quality is likely to be more important to insect herbivores than is spatial heterogeneity and that other factors, such as the abiotic environment and natural enemies, likely have substantial effects on herbivore density. PMID:19689895

  12. Effects of elevated CO2 on foliar quality and herbivore damage in a scrub oak ecosystem.

    PubMed

    Hall, Myra C; Stiling, Peter; Moon, Daniel C; Drake, Bert G; Hunter, Mark D

    2005-02-01

    Atmospheric CO2 concentrations have increased exponentially over the last century and continuing increases are expected to have significant effects on ecosystems. We investigated the interactions among atmospheric CO2, foliar quality, and herbivory within a scrub oak community at the Kennedy Space Center, Florida. Sixteen plots of open-top chambers were followed; eight of which were exposed to ambient levels of CO2 (350 ppm), and eight of which were exposed to elevated levels of CO2 (700 ppm). We focused on three oak species, Quercus geminata, Quercus myrtifolia, Quercus chapmanii, and one nitrogen fixing legume, Galactia elliottii. There were declines in overall nitrogen and increases in C:N ratios under elevated CO2. Total carbon, phenolics (condensed tannins, hydrolyzable tannins, total phenolics) and fiber (cellulose, hemicellulose, lignin) did not change under elevated CO2 across plant species. Plant species differed in their relative foliar chemistries over time, however, the only consistent differences were higher nitrogen concentrations and lower C:N ratios in the nitrogen fixer when compared to the oak species. Under elevated CO2, damage by herbivores decreased for four of the six insect groups investigated. The overall declines in both foliar quality and herbivory under elevated CO2 treatments suggest that damage to plants may decline as atmospheric CO2 levels continue to rise. PMID:15856783

  13. Functional and biological diversity of foliar spectra in tree canopies throughout the Andes to Amazon region.

    PubMed

    Asner, Gregory P; Martin, Roberta E; Carranza-Jimnez, Loreli; Sinca, Felipe; Tupayachi, Raul; Anderson, Christopher B; Martinez, Paola

    2014-10-01

    Spectral properties of foliage express fundamental chemical interactions of canopies with solar radiation. However, the degree to which leaf spectra track chemical traits across environmental gradients in tropical forests is unknown. We analyzed leaf reflectance and transmittance spectra in 2567 tropical canopy trees comprising 1449 species in 17 forests along a 3400-m elevation and soil fertility gradient from the Amazonian lowlands to the Andean treeline. We developed quantitative links between 21 leaf traits and 400-2500-nm spectra, and developed classifications of tree taxa based on spectral traits. Our results reveal enormous inter-specific variation in spectral and chemical traits among canopy trees of the western Amazon. Chemical traits mediating primary production were tightly linked to elevational changes in foliar spectral signatures. By contrast, defense compounds and rock-derived nutrients tracked foliar spectral variation with changing soil fertility in the lowlands. Despite the effects of abiotic filtering on mean foliar spectral properties of tree communities, the spectra were dominated by phylogeny within any given community, and spectroscopy accurately classified 85-93% of Amazonian tree species. Our findings quantify how tropical tree canopies interact with sunlight, and indicate how to measure the functional and biological diversity of forests with spectroscopy. PMID:24942328

  14. Population divergence in the ontogenetic trajectories of foliar terpenes of a Eucalyptus species

    PubMed Central

    Borzak, Christina L.; Potts, Brad M.; Davies, Noel W.; O’Reilly-Wapstra, Julianne M.

    2015-01-01

    Background and Aims The development of plant secondary metabolites during early life stages can have significant ecological and evolutionary implications for plant–herbivore interactions. Foliar terpenes influence a broad range of ecological interactions, including plant defence, and their expression may be influenced by ontogenetic and genetic factors. This study investigates the role of these factors in the expression of foliar terpene compounds in Eucalyptus globulus seedlings. Methods Seedlings were sourced from ten families each from three genetically distinct populations, representing relatively high and low chemical resistance to mammalian herbivory. Cotyledon-stage seedlings and consecutive leaf pairs of true leaves were harvested separately across an 8-month period, and analysed for eight monoterpene compounds and six sesquiterpene compounds. Key Results Foliar terpenes showed a series of dynamic changes with ontogenetic trajectories differing between populations and families, as well as between and within the two major terpene classes. Sesquiterpenes changed rapidly through ontogeny and expressed opposing trajectories between compounds, but showed consistency in pattern between populations. Conversely, changed expression in monoterpene trajectories was population- and compound-specific. Conclusions The results suggest that adaptive opportunities exist for changing levels of terpene content through ontogeny, and evolution may exploit the ontogenetic patterns of change in these compounds to create a diverse ontogenetic chemical mosaic with which to defend the plant. It is hypothesized that the observed genetically based patterns in terpene ontogenetic trajectories reflect multiple changes in the regulation of genes throughout different terpene biosynthetic pathways. PMID:25434028

  15. Calcium carbonate and calcium sulfate in Martian meteorite EETA79001

    NASA Technical Reports Server (NTRS)

    Gooding, J. L.; Wentworth, S. J.

    1987-01-01

    Chips of glassy Lithology C of EETA79001 were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy to determine the mineralogy and petrogenesis of the glass that was shown by others to contain trapped Mars-like gases. Calcium carbonite was identified as massive to acicular crystals for which Ca, C, and O were the major elements. Calcium sulfate was identified as prismatic-acicular crystals with Ca and S as the major elements.

  16. Effects of acid deposition on calcium nutrition and health of Southern Appalachian spruce fir forests

    SciTech Connect

    McLaughlin, S.B.; Wullschleger, S.; Stone, A.; Wimmer, R.; Joslin, J.D.

    1995-02-01

    The role of acid deposition in the health of spruce fir forests in the Southern Appalachian Mountains has been investigated by a wide variety of experimental approaches during the past 10 years. These studies have proceeded from initial dendroecological documentation of altered growth patterns of mature trees to increasingly more focused ecophysiological research on the causes and characteristics of changes in system function associated with increased acidic deposition. Field studies across gradients in deposition and soil chemistry have been located on four mountains spanning 85 km of latitude within the Southern Appalachians. The conclusion that calcium nutrition is an important component regulating health of red spruce in the Southern Appalachians and that acid deposition significantly reduces calcium availability in several ways has emerged as a consistent result from multiple lines or research. These have included analysis of trends in wood chemistry, soil solution chemistry, foliar nutrition, gas exchange physiology, root histochemistry, and controlled laboratory and field studies in which acid deposition and/or calcium nutrition has been manipulated and growth and nutritional status of saplings or mature red spruce trees measured. This earlier research has led us to investigate the broader implications and consequences of calcium deficiency for changing resistance of spruce-fir forests to natural stresses. Current research is exploring possible relationships between altered calcium nutrition and shifts in response of Fraser fir to insect attack by the balsam wooly adelgid. In addition, changes in wood ultrastructural properties in relation to altered wood chemistry is being examined to evaluate its possible role in canopy deterioration, under wind and ice stresses typical of high elevation forests.

  17. Calcium/Calmodulin-Mediated Gravitropic Response in Plants

    NASA Technical Reports Server (NTRS)

    Poovaiah, B. W.

    2002-01-01

    The goal of this project was to gain a fundamental understanding of how calcium/calmodulin-mediated signaling is involved in gravity signal transduction in plants. During the period of support, significant progress was made in elucidating the role of calmodulin and its target proteins in gravitropism. This laboratory has made breakthroughs by cloning and characterizing genes that are involved in calcium/calmodulin-mediated signaling. Some of these genes show altered expression under hypergravity and simulated microgravity conditions. A major advance was made in our attempts to understand gravity signal transduction by cloning and characterizing a catalase which requires calcium/calmodulin for its activation. Our results suggest that calcium/calmodulin have dual roles in regulating the level of hydrogen peroxide (H202), a signal molecule that plays a major role in gravitropism. It is well established that auxin plays a major role in gravitropism. Our results indicate that there is a 'cross-talk' between calcium/calmodulin-mediated signaling and auxin-mediated signal transduction. Auxin-regulated SAUR proteins that are involved in gravitropism bind to calmodulin in a calcium-dependent manner. A novel chimeric calcium/calmodulin-dependent protein kinase was cloned and characterized and its role in gravity signal transduction was investigated. These studies have provided some answers to the fundamental questions about how signal molecules such as calcium, H202, and hormones such as auxin bring about the ultimate gravitropic response and the integral role of calmodulin in gravity signal transduction. This NASA-funded study has led to some spinoffs that have applications in solving agricultural problems. The Washington State University Research Foundation has obtained several patents related to this work.

  18. Fast Spatiotemporal Smoothing of Calcium Measurements in Dendritic Trees

    PubMed Central

    Pnevmatikakis, Eftychios A.; Kelleher, Keith; Chen, Rebecca; Saggau, Petter; Josić, Krešimir; Paninski, Liam

    2012-01-01

    We discuss methods for fast spatiotemporal smoothing of calcium signals in dendritic trees, given single-trial, spatially localized imaging data obtained via multi-photon microscopy. By analyzing the dynamics of calcium binding to probe molecules and the effects of the imaging procedure, we show that calcium concentration can be estimated up to an affine transformation, i.e., an additive and multiplicative constant. To obtain a full spatiotemporal estimate, we model calcium dynamics within the cell using a functional approach. The evolution of calcium concentration is represented through a smaller set of hidden variables that incorporate fast transients due to backpropagating action potentials (bAPs), or other forms of stimulation. Because of the resulting state space structure, inference can be done in linear time using forward-backward maximum-a-posteriori methods. Non-negativity constraints on the calcium concentration can also be incorporated using a log-barrier method that does not affect the computational scaling. Moreover, by exploiting the neuronal tree structure we show that the cost of the algorithm is also linear in the size of the dendritic tree, making the approach applicable to arbitrarily large trees. We apply this algorithm to data obtained from hippocampal CA1 pyramidal cells with experimentally evoked bAPs, some of which were paired with excitatory postsynaptic potentials (EPSPs). The algorithm recovers the timing of the bAPs and provides an estimate of the induced calcium transient throughout the tree. The proposed methods could be used to further understand the interplay between bAPs and EPSPs in synaptic strength modification. More generally, this approach allows us to infer the concentration on intracellular calcium across the dendritic tree from noisy observations at a discrete set of points in space. PMID:22787437

  19. Anodic Behavior of Alloy 22 in Calcium Chloride and in Calcium Chloride Plus Calcium Nitrate Brines

    SciTech Connect

    Evans, K J; Day, S D; Ilevbare, G O; Whalen, M T; King, K J; Hust, G A; Wong, L L; Estill, J C; Rebak, R B

    2003-05-13

    Alloy 22 (UNS N60622) is a nickel-based alloy, which is extensively used in aggressive industrial applications, especially due to its resistance to localized corrosion and stress corrosion cracking in high chloride environments. The purpose of this work was to characterize the anodic behavior of Alloy 22 in concentrated calcium chloride (CaCl{sub 2}) brines and to evaluate the inhibitive effect of nitrate, especially to localized corrosion. Standard electrochemical tests such as polarization resistance and cyclic polarization were used. Results show that the corrosion potential of Alloy 22 was approximately -360 mV in the silver-silver chloride (SSC) scale and independent of the tested temperature. Cyclic polarization tests showed that Alloy 22 was mainly susceptible to localized attack in 5 M CaCl{sub 2} at 75 C and higher temperatures. The addition of nitrate in a molar ratio of chloride to nitrate equal to 10 increased the onset of localized corrosion to approximately 105 C. The addition of nitrate to the solution also decreased the uniform corrosion rate and the passive current of the alloy.

  20. Formate Oxidation-Driven Calcium Carbonate Precipitation by Methylocystis parvus OBBP

    PubMed Central

    Ganendra, Giovanni; De Muynck, Willem; Ho, Adrian; Arvaniti, Eleni Charalampous; Hosseinkhani, Baharak; Ramos, Jose Angel; Rahier, Hubert

    2014-01-01

    Microbially induced carbonate precipitation (MICP) applied in the construction industry poses several disadvantages such as ammonia release to the air and nitric acid production. An alternative MICP from calcium formate by Methylocystis parvus OBBP is presented here to overcome these disadvantages. To induce calcium carbonate precipitation, M. parvus was incubated at different calcium formate concentrations and starting culture densities. Up to 91.4% ± 1.6% of the initial calcium was precipitated in the methane-amended cultures compared to 35.1% ± 11.9% when methane was not added. Because the bacteria could only utilize methane for growth, higher culture densities and subsequently calcium removals were exhibited in the cultures when methane was added. A higher calcium carbonate precipitate yield was obtained when higher culture densities were used but not necessarily when more calcium formate was added. This was mainly due to salt inhibition of the bacterial activity at a high calcium formate concentration. A maximum 0.67 ± 0.03 g of CaCO3 g of Ca(CHOOH)2−1 calcium carbonate precipitate yield was obtained when a culture of 109 cells ml−1 and 5 g of calcium formate liter−1 were used. Compared to the current strategy employing biogenic urea degradation as the basis for MICP, our approach presents significant improvements in the environmental sustainability of the application in the construction industry. PMID:24837386