Sample records for calcium chloride cacl2

  1. Monodisperse Calcium Carbonate Microtablets Forming at 701C in Prerefrigerated CaCl2GelatinUrea Solutions

    E-print Network

    Tas, A. Cuneyt

    Monodisperse Calcium Carbonate Microtablets Forming at 701C in Prerefrigerated CaCl2­Gelatin Calcium carbonate particles with a unique tablet shape were produced by simply aging the prerefrigerated, and powder X-ray diffraction. Introduction Calcium carbonate (CaCO3) is an important ma- terial of marine

  2. 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

  3. Inhibition of nitrite-induced toxicity in channel catfish by calcium chloride and sodium chloride

    USGS Publications Warehouse

    Tommasso J.R., Wright, M. I.; Simco, B.A.; Davis, K.B.

    1980-01-01

    Environmental chloride has been shown to inhibit methemoglobin formation in fish, thereby offering a protective effect against nitrite toxicity. Channel catfish (Ictalurus punctatus) were simultaneously exposed to various environmental nitrite and chloride levels (as either CaCl2 or NaCl) in dechlorinated tap water (40 mg/L total hardness, 47 mg/L alkalinity, 4 mg/L chloride, pH = 6.9-7.1, and temperature 21-24°C). Methemoglobin levels in fish simultaneously exposed to 2.5 mg/L nitrite and up to 30 mg/L chloride as either CaCl2 or NaCl were similar but significantly lower than in unprotected fish. Exposure to 10 mg/L nitrite and 60 mg/L chloride resulted in methemoglobin levels similar to those of the controls; most unprotected fish died. Fish exposed to 10 mg/L nitrite had significantly lower methemoglobin levels when protected with 15.0 mg/L chloride as CaCl2 than with NaCl. Fish exposed to nitrite in the presence of 60 mg/L chloride (as either CaCl2 or NaCl) had similar 24-h LC50 values that were significantly elevated above those obtained in the absence of chloride. Calcium had little effect on tolerance to nitrite toxicity in channel catfish in contrast to its large effect reported in steelhead trout (Salmo gairdneri).

  4. Consumer Acceptability of Cucumber Pickles Produced by Fermentation in Calcium Chloride Brine for Reduced Environmental Impact.

    PubMed

    Wilson, Emily M; Johanningsmeier, Suzanne D; Osborne, Jason A

    2015-06-01

    Fermentation of cucumbers in calcium chloride (CaCl2 ) brine has been proposed as an alternative process to reduce the environmental impact of traditional, high salt fermentations. The objective of this research was to determine whether consumer acceptability of pickle products would be impacted by fermentation and storage of cucumbers in CaCl2 brine. Cucumbers were fermented and stored with 0.1M CaCl2 or 1M sodium chloride (NaCl) in open-air, 3000 gal tanks at a commercial facility and processed into hamburger dill chips containing 0.38M NaCl. Cucumbers fermented in CaCl2 required additional desalting to reduce CaCl2 concentrations to that of current products. Consumers (n = 101) showed no significant preference for pickles from different fermentation treatments, whether stored for 2 mo (P = 0.75) or 8 mo (P = 0.68) prior to processing. In contrast, NaCl fermented pickles were preferred over CaCl2 fermented pickles stored for 10 mo and desalted only once (P < 0.01). A series of preference tests indicated that the taste of CaCl2 was not the factor affecting consumer preference, and the 50% detection threshold of CaCl2 in dill pickle chips was found to be 61.8 ± 7.6 mM, indicating that processors could potentially use CaCl2 fermentations with a single desalting step. Consumer liking of flavor (n = 73) was not influenced by fermentation in CaCl2 or by 23 or 35 mM CaCl2 in finished products (P > 0.05), but variability in texture decreased consumer liking (P < 0.05). Although promising, individual fermentation variability and texture quality of CaCl2 fermented products should be further evaluated prior to broad implementation of this process. PMID:25981784

  5. 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

  6. Sanitary dips with calcium propionate, calcium chloride, or a calcium amino acid chelate maintain quality and shelf stability of fresh-cut honeydew chunks

    Microsoft Academic Search

    Robert A. Saftner; Jinhe Bai; Judith A. Abbott; Yuen S. Lee

    2003-01-01

    Freshly cut honeydew chunks were dipped for 30 s in a solution containing 1.9 mM hypochlorous acid (ClO) without or with a 40 mM concentration of calcium (Ca) propionate, Ca amino acid chelate formulation (Ca chelate), calcium chloride (CaCl2), or not treated. Respiration and ethylene production rates, firmness, translucency, microbiological and sensory characteristics, surface color, volatile abundance, and tissue calcium

  7. The time courses of intracellular free calcium and related electrical effects after injection of CaCl 2 into neurons of the snail, Helix pomatia

    Microsoft Academic Search

    G. Hofmeier; H. D. Lux

    1981-01-01

    Controlled quantities of 100 mM aqueous CaCl2 solutions were pressure injected into voltage-clamped neurons with a resolution of 10-11 1. Ca2+-selective microelectrodes monitored the time course of changes in [Ca2+]i. At a membrane potential of -50 mV CaCl2 quantities in the range of 1% of the cell volume induced an inward current, associated with a conductance increase and having an

  8. Raman spectroscopic studies of chemical speciation in calcium chloride melts

    SciTech Connect

    Windisch, Charles F.; Lavender, Curt A.

    2005-02-01

    Raman spectroscopy was applied to CaCl2 melts at 900 degrees C under both non-electrolyzed and electrolyzed conditions. The later used titania cathodes supplied by TIMET, Inc. and graphite anodes. Use of pulse-gating to collect the Raman spectra successfully eliminated any interference from black-body radiation and other stray light. The spectrum of molten CaCl2 exhibited no distinct, resolvable bands that could be correlated with a calcium chloride complex similar to MgCl42- in MgCl2 melts. Rather, the low frequency region of the spectrum was dominated by a broad “tail” arising from collective oscillations of both charge and mass in the molten salt “network.” Additions of both CaO and Ca at concentrations of a percent or two resulted in no new features in the spectra. Addition of CO2, both chemically and via electrolysis at concentrations dictated by stability and solubility at 900 degrees C and 1 bar pressure, also produced no new bands that could be correlated with either dissolved CO2 or the carbonate ion. These results indicated that Raman spectroscopy, at least under the conditions evaluated in the research, was not well suited for following the reactions and coordination chemistry of calcium ions, nor species such as dissolved metallic Ca and CO2 that are suspected to impact current efficiency in titanium electrolysis cells using molten CaCl2. Raman spectra of TIMET titania electrodes were successfully obtained as a function of temperature up to 900 degrees C, both in air and in-situ in CaCl2 melts. However, spectra of these electrodes could only be obtained when the material was in the unreduced state. When reduced, either with hydrogen or within an electrolysis cell, the resulting electrodes exhibited no measurable Raman bands under the conditions used in this work.

  9. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Agriculture 3 2011-01-01 2011-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture...Quality Specifications for Raw Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the...

  10. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...Agriculture 3 2010-01-01 2010-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture...Quality Specifications for Raw Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the...

  11. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Agriculture 3 2012-01-01 2012-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture...Quality Specifications for Raw Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the...

  12. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Agriculture 3 2014-01-01 2014-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture...Quality Specifications for Raw Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the...

  13. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Agriculture 3 2013-01-01 2013-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture...Quality Specifications for Raw Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the...

  14. Desorption of CO2 from low concentration monoethanolamine solutions using calcium chloride and ultrasound irradiation

    NASA Astrophysics Data System (ADS)

    Tanaka, Kosuke; Okawa, Hirokazu; Fujiwara, Tatsuo; Kato, Takahiro; Sugawara, Katsuyasu

    2015-07-01

    We developed an effective method for desorbing CO2 from low-concentration (0.2 mol/l) monoethanolamine (MEA) solutions using calcium chloride (CaCl2) and ultrasound irradiation at 25 °C. The proportion of CO2 desorbed from the MEA solution was calculated from the amount of CaCO3 generated and the amount of CO2 emitted. The proportion of CO2 desorbed from the MEA solution was much higher when CaCl2 was added than when CaCl2 was not added. We also characterized the CaCO3 that was generated when the solution was treated with ultrasound irradiation and when the solution was stirred. The CaCO3 particles produced were more homogeneous and smaller when ultrasound irradiation was applied than when the solution was stirred.

  15. Biomimetic apatite formation on calcium phosphate-coated titanium in Dulbecco's phosphate-buffered saline solution containing CaCl(2) with and without fibronectin.

    PubMed

    Chen, Cen; Lee, In-Seop; Zhang, Sheng-Min; Yang, Hyeong Cheol

    2010-06-01

    Calcium phosphate (CaP) thin films with different degrees of crystallinity were coated on the surfaces of commercially pure titanium by electron beam evaporation. The details of apatite nucleation and growth on the coating layer were investigated in Dulbecco's phosphate-buffered saline solutions containing calcium chloride (DPBS) or DPBS with fibronectin (DPBSF). The surfaces of the samples were examined by field emission scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The concentrations of fibronectin and calcium ions (Ca(2+)) were monitored by the bicinchoninic acid method (BCA) and use of a calcium assay kit (DICA-500), respectively. Apatite initially formed at the fastest rate on the CaP-coated samples with the lowest degree of crystallinity and reached the maximum Ca(2+) concentration after immersion in DPBS solution for 15min. After 15min the concentration of Ca(2+) decreased with the growth of apatite on the coating layers. For all the samples the maximum Ca(2+) concentration in the DPBS solutions decreased with increasing crystallinity and immersion time to reach the maximum concentration increased. The presence of fibronectin in the DPBS solutions delayed the formation and affected the morphology of the apatite. Fibronectin incorporated into apatite deposited on the surface of titanium did not affect its biological activity in terms of promoting osteoblast adhesion. PMID:19962459

  16. The effect of calcium chloride on growth, photosynthesis, and antioxidant responses of Zoysia japonica under drought conditions.

    PubMed

    Xu, Chengbin; Li, Xuemei; Zhang, Lihong

    2013-01-01

    Few attempts have been made to study the alleviating effects of signal molecules on zoysiagrass (Zoysiajaponica) under drought stress. Calcium chloride has been shown to ameliorate the adverse effects of drought stress on many plants. It is necessary to investigate how to enhance drought tolerance of zoysiagrass using calcium chloride. The study elucidated the effects of calcium chloride on zoysiagrass under drought conditions by investigating the following parameters: biomass, chlorophyll (Chl) content, net photosynthetic rate (Pn), chlorophyll fluorescence, antioxidant enzymes, proline content, and malondialdehyde (MDA) content. Experimental conditions consisted of an aqueous CaCl2 solution at 5, 10, and 20 mM sprayed on zoysiagrass leaves for 3 d, following by an inducement of drought conditions by withholding water for 16 d. Under drought conditions, all CaCl2 pretreatments were found to increase the above-ground fresh biomass, as well as below-ground fresh and dry biomass. The resulting Chl (a, b, a+b) contents of the 5 and 10 mM CaCl2 pretreatment groups were higher than those of the control. In the later stages of drought conditions, the chlorophyll fluorescence parameter Fv/Fm was higher in leaves treated with 10 mM CaCl2 than in the leaves of the other two treatment groups. Zoysiagrass pretreated with 10 mM CaCl2 possessed both the maximum observed Pn and antioxidant enzyme activities. Meanwhile, lower MDA and proline contents were recorded in the plants pretreated with 5 and 10 mM CaCl2 under drought conditions. As a whole, the drought tolerance of zoysiagrass was improved to some extent by the application of a moderate calcium concentration. PMID:23844172

  17. The Effect of Calcium Chloride on Growth, Photosynthesis, and Antioxidant Responses of Zoysia japonica under Drought Conditions

    PubMed Central

    Xu, Chengbin; Li, Xuemei; Zhang, Lihong

    2013-01-01

    Few attempts have been made to study the alleviating effects of signal molecules on zoysiagrass (Zoysiajaponica) under drought stress. Calcium chloride has been shown to ameliorate the adverse effects of drought stress on many plants. It is necessary to investigate how to enhance drought tolerance of zoysiagrass using calcium chloride. The study elucidated the effects of calcium chloride on zoysiagrass under drought conditions by investigating the following parameters: biomass, chlorophyll (Chl) content, net photosynthetic rate (Pn), chlorophyll fluorescence, antioxidant enzymes, proline content, and malondialdehyde (MDA) content. Experimental conditions consisted of an aqueous CaCl2 solution at 5, 10, and 20 mM sprayed on zoysiagrass leaves for 3 d, following by an inducement of drought conditions by withholding water for 16 d. Under drought conditions, all CaCl2 pretreatments were found to increase the above-ground fresh biomass, as well as below-ground fresh and dry biomass. The resulting Chl (a, b, a+b) contents of the 5 and 10 mM CaCl2 pretreatment groups were higher than those of the control. In the later stages of drought conditions, the chlorophyll fluorescence parameter Fv/Fm was higher in leaves treated with 10 mM CaCl2 than in the leaves of the other two treatment groups. Zoysiagrass pretreated with 10 mM CaCl2 possessed both the maximum observed Pn and antioxidant enzyme activities. Meanwhile, lower MDA and proline contents were recorded in the plants pretreated with 5 and 10 mM CaCl2 under drought conditions. As a whole, the drought tolerance of zoysiagrass was improved to some extent by the application of a moderate calcium concentration. PMID:23844172

  18. Quality and ‘Conference’ Pear Storability as Influenced by Preharvest Sprays of Calcium Chloride

    Microsoft Academic Search

    Pawe? Wójcik

    2012-01-01

    The aim of the study was to examine impacts of calcium chloride (CaCl2) sprays on quality and ‘Conference’ pear (Pyrus communis L.) storability. The experiment was carried out during 2002–2008 at a commercial orchard in Central Poland, on mature pear trees grafted on Quince S1 (Cydonia oblonga Mill.). The trees were planted at a spacing of 3.5 × 1.5 m, on

  19. Bermudagrass response to surface-applied urea amended with calcium chloride or ammonium thiosulfate

    Microsoft Academic Search

    John J. Sloan; Warren B. Anderson

    2001-01-01

    Surface-applied urea fertilizers are susceptible to hydrolysis and loss of nitrogen (N) through NH3 volatilization when conditions favorable for these processes exist. Calcium chloride (CaCl2) and ammonium thiosulfate (ATS) have been proposed as possible urease and NH3 volatilization inhibitors. The main objective of this research was to compare the efficacy of various N fertilizer sources on bermudagrass yield and fertilizer

  20. Calcium chloride penetrates plant cuticles via aqueous pores.

    PubMed

    Schönherr, J

    2000-12-01

    Penetration of calcium chloride across astomatous cuticular membranes (CMs) isolated from leaves of Pyrus communis L. has been studied. Penetration was a first-order process when calcium chloride concentrations ranged from 2 gl(-1) to 10 gl(-1). Rate constants were increased 10-fold by adding wetting agents but they did not depend on temperature. The accelerators tributyl phosphate and diethyl sebacate had no effect on rates of penetration. Increasing humidity over the salt residue on the CMs from 50 to 90% increased rate constants by about 2-fold. Extracting cuticular waxes from pear leaf CMs increased rate constants by factors of 2 to 3, depending on humidity. Leaf CMs from Malus domestica Borkh., Populus aelha L., Stephanotis floribunda Brongn. and Schefflera actinophylla (Endl.) Harms were also permeable to CaCl2. Highest rate constants were observed with poplar CMs while Schefflera CMs exhibited the lowest permeability. By comparing these results with the well established transport properties of the lipophilic pathway it is concluded that calcium chloride hexahydrate penetrated cuticular membranes via aqueous pores. PMID:11219575

  1. Effects of CaCl2 hydrothermal treatment of titanium implant surfaces on early epithelial sealing.

    PubMed

    Oshiro, Wakana; Ayukawa, Yasunori; Atsuta, Ikiru; Furuhashi, Akihiro; Yamazoe, Jyunichi; Kondo, Ryosuke; Sakaguchi, Mami; Matsuura, Yuri; Tsukiyama, Yoshihiro; Koyano, Kiyoshi

    2015-07-01

    Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. We aimed to investigate whether calcium chloride (CaCl2) hydrothermally treated (HT) Ti could promote sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with either CaCl2-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group), or untreated implants (Cont group). After 4 weeks, the implant-PIE interface of the Ca-HT group exhibited a band of immunoreactive laminin-332, similar to the tooth-junctional epithelium interface, which was absent in the Cont and DW-HT groups at the upper portion. We also investigated the effect of Ca-HT on the attachment of rat oral epithelial cells (OECs). OEC adherence onto Ca-HT Ti plates was stronger with higher expression levels of adhesion proteins compared with Cont and DW-HT groups. These results indicate that HT with CaCl2 improves the integration of soft tissue cells with the Ti implant at 4 weeks after implantation, which might facilitate the development of a soft tissue barrier around the implant. PMID:25982317

  2. The Thermodynamic Activity of Calcium Ion in Sodium Chloride-Calcium Chloride Electrolytes

    PubMed Central

    Butler, James N.

    1968-01-01

    Experimental data on the mean activity coefficient of CaCl2 in NaCl-CaCl2 mixtures at ionic strengths below 1 m have been used to prepare a table of activity coefficients for Ca++ in solutions of physiological interest. The establishment of an empirical calcium ion activity scale is discussed, and a number of possible assumptions are examined. The assumption ?++ = (?±)2 is suggested as being the simplest with a theoretical basis. PMID:5713452

  3. Interactive role of nitric oxide and calcium chloride in enhancing tolerance to salt stress.

    PubMed

    Khan, M Nasir; Siddiqui, Manzer H; Mohammad, Firoz; Naeem, M

    2012-12-01

    Nitric oxide (NO), a small diffusible, ubiquitous bioactive molecule, acts as prooxidant as well as antioxidant, and also regulates remarkable spectrum of plant cellular mechanisms. The present work was undertaken to investigate the role of nitric oxide donor sodium nitroprusside (SNP) and/or calcium chloride (CaCl(2)) in the tolerance of excised mustard leaves to salt stress. After 24h, salt stressed leaves treated with SNP and/or CaCl(2), showed an improvement in the activities of carbonic anhydrase (CA) and nitrate reductase (NR), and leaf chlorophyll (Chl) content, leaf relative water content (LRWC) and leaf ion concentration as compared with the leaves treated with NaCl only. Salinity stress caused a significant increase in H(2)O(2) content and membrane damage which is witnessed by enhanced levels of thiobarbituric acid reactive substances (TBARS) and electrolyte leakage. By contrast, such increases were blocked by the application of 0.2mM SNP and 10mM CaCl(2) to salt stressed leaves. Application of SNP and/or CaCl(2) alleviated NaCl stress by enhancing the activities of antioxidative enzymes viz. superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX) and glutathione reductase (GR) and by enhancing proline (Pro) and glycinebetaine (GB) accumulation with a concomitant decrease in H(2)O(2) content, TBARS and electrolyte leakage, which is manifested in the tolerance of plants to salinity stress. Moreover, application of SNP with CaCl(2) was more effective to reduce the detrimental effects of NaCl stress on excised mustard leaves. In addition to this, ameliorating effect of SNP was not effective in presence of NO scavenger cPTIO [2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide]. To put all these in a nut shell, the results advocate that SNP in association with CaCl(2) plays a role in enhancing the tolerance of plants to salt stress by improving antioxidative defence system, osmolyte accumulation and ionic homeostasis. PMID:22884961

  4. Evaluation of single intratesticular injection of calcium chloride for nonsurgical sterilization of male Black Bengal goats ( Capra hircus): a dose-dependent study

    Microsoft Academic Search

    Kuladip Jana; P. K. Samanta; D. Ghosh

    2005-01-01

    This study describes the induction of chemosterilization in three groups each of six adult male Black Bengal goats at 30 days after a single bilateral intratesticular injection of a calcium chloride (CaCl2, 2H2O) solution at the doses of 10, 20 or 40mg\\/kg body weight\\/testis, always in a 2ml volume of normal saline. Another one group of animals received only 2ml

  5. Predicting Phase Diagram of the CaCl2-H2O Binary System from the BET Adsorption Isotherm

    SciTech Connect

    Ally, Moonis Raza [ORNL

    2008-01-01

    A recent publication in Fluid Phase Equilibria by Zeng (Zeng, Zhou et al. 2007) claimed remarkable accuracy in predicting the solubility of CaCl2-H2O solutions with the Brunaruer-Emett-Teller (BET) model parameters. Their approach necessarily requires prior knowledge of equilibrium water vapor pressures above saturated solutions as a function of temperature for the hydrates of CaCl2 that exist under those conditions. However, the intrinsic BET model does not require prior knowledge of such solubility data that the approach of (Zeng, Zhou et al. 2007) is dependent upon. This paper highlights the differences between the two approaches and covers a much wider range of compositions and temperatures than is done by (Zeng, Zhou et al. 2007). The statistical mechanical description of multilayer adsorption culminating in the BET adsorption isotherm for aqueous electrolytes as developed by Ally and Braunstein (Ally and Braunstein 1993) is used to predict the liquidus behavior of CaCl2-H2O across the entire composition range (from the melting point of pure water to the melting point of anhydrous calcium chloride), including possible metastable crystalline phases. The method requires as input the two BET parameters r, the statistically averaged number of adsorption sites and ?, the energy of adsorption of water in excess of the energy of condensation of pure water. Usually it suffices to keep r and ? constant, typically evaluated at 298.15 K, but in the case of CaCl2-H2O, it is found that both r and ? must be considered temperature dependent in order to predict the liquidus curve, eutectic and peritectic points with reasonable accuracy over the large temperature and compositional range for this binary system.

  6. Advanced calcium thionyl chloride high power battery

    NASA Astrophysics Data System (ADS)

    Peled, Emanuel

    1989-11-01

    In this phase we have demonstrated that an improved c-size Ca/TC A type cell can deliver at RT up to 5.5 Ah at low rates and 4.4 Ah at 0.9A rate. It has 10 to 80 percent more capacity than have commercial Li-TC and Li-SO2 wound C-size cells. The improved Ca-TC cell lost almost no capacity after 4 to 5 weeks of storage at 70 C. It generates less heat at 20 C under OCV conditions than equivalent Li/TC cells, having the same electrode area, i.e., it has a longer shelf life. The improved shelf-life of calcium in BaX2/TC solutions as compared to CaX2/TC solutions results mainly from the difference in the solubility or reactivity of the CaO film in those two solutions. In CaX2/TC solutions the oxide dissolves leaving the calcium with a CaCl2 layer which does not provide the metal with good protection. In BaX2/TC solutions, on the native CaO layer a BaCl2 and AlCl3 or Al2O3 layer is formed. This BaCl3, AlCl3, and Al2O3 layer does not form when the oxide is missing from the surface. Therefore cleaned calcium in BaX2/TC solution corrodes at the same rate as does calcium in CaX2/TC solutions.

  7. Leaching of lead from zinc leach residue in acidic calcium chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Wang, Le; Mu, Wen-ning; Shen, Hong-tao; Liu, Shao-ming; Zhai, Yu-chun

    2015-05-01

    A process with potentially reduced environmental impacts and occupational hazards of lead-bearing zinc plant residue was studied to achieve a higher recovery of lead via a cost-effective and environmentally friendly process. This paper describes an optimization study on the leaching of lead from zinc leach residue using acidic calcium chloride aqueous solution. Six main process conditions, i.e., the solution pH value, stirring rate, concentration of CaCl2 aqueous solution, liquid-to-solid (L/S) ratio, leaching temperature, and leaching time, were investigated. The microstructure and components of the residue and tailing were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). On the basis of experimental results, the optimum reaction conditions were determined to be a solution pH value of 1, a stirring rate of 500 r·min-1, a CaCl2 aqueous solution concentration of 400 g·L-1, a liquid-to-solid mass ratio of 7:1, a leaching temperature of 80°C, and a leaching time of 45 min. The leaching rate of lead under these conditions reached 93.79%, with an iron dissolution rate of 19.28%. Silica did not take part in the chemical reaction during the leaching process and was accumulated in the residue.

  8. EFEITO DA ADIÇÃO DE CLORET O DE CÁLCIO SOBRE A QUALIDADE ESPERMÁTICA E ATIVIDADE DA ASPARTATO AMINO TRANSFERASE NO SÊMEN RESFRIADO DE SUÍNO 1 Effect of adding calcium chloride on the spermatic quality and aminotransferase aspartate in cool swine semen1

    Microsoft Academic Search

    Fernanda Pinheiro Lima; Luis David; Solis Murgas; Silvio Luiz de Oliveira; Daniele de Lima; Ana Luísa; Neves Alvarenga; Elias Tadeu Fialho

    The study was carried out with objective to test two swine semen cooling processes and verify the effects of adding chloride of calcium (CaCl 2) on semen dilutor BTS and also to test the evaluation method of Aspartate Aminotransferase (AAT) enzymatic profile on the cooled swine semen spermatic quality. Were used twelve samples of ejaculation of breeders supplied by the

  9. CHLORIDE, IN CALCIUM, IN pH ARSENIC, IN

    E-print Network

    CHLORIDE, IN CALCIUM, IN pH ARSENIC, IN MILLIGRAMS PER LITER MILLIGRAMS PER LITER MICROGRAMS PER concentrations, calcium concentrations, arsenic concentrations and pH after 100,000 years of simulated ground-water flow and reaction. View is from the northwest looking to the southeast. CHLORIDE, IN CALCIUM, IN p

  10. Laboratory studies of the low-temperature deliquescence of calcium chloride salts: Relevance to aqueous solutions on Mars and in the Antarctic Dry Valleys

    NASA Astrophysics Data System (ADS)

    Gough, R. V.; Chevrier, V.; Tolbert, M. A.

    2013-12-01

    There is significant interest in the possible existence of liquid water on current Mars. This water would likely exist as a brine in order to be stable on Mars today. It has been proposed that soil salts could form aqueous solutions through either the melting of ice by low-eutectic salts, or by the deliquescence of hygroscopic salts present in the Martian soil. The focus thus far has largely been on perchlorate species, which can melt ice at temperatures as low as 206 K and can deliquesce at relative humidity values as low as 38% RH. A Mars-relevant salt that has been neglected thus far is calcium chloride (CaCl2). Calcium has been reported to be an abundant cation at the Phoenix landing site and Mars Science Laboratory instruments have recently identified calcium as well. Simulations suggest subsurface CaCl2 is an ideal candidate to produce brines with seasonality consistent with observed recurring slope lineae (RSL) (Chevrier et al., 2012). Finally, the only terrestrial site where RSL-like features have been observed (near Don Juan Pond in the Antarctic Dry Valleys) contains abundant CaCl2. These seasonal slope streaks are thought to form when CaCl2 in the soil deliquesces due to contact with atmospheric water vapor (Dickson et al., 2013). It is important to understand how this CaCl2 interacts with water vapor at low temperatures relevant to Mars and the Martian analog sites. Here we use a Raman microscope and environmental cell to monitor the low-temperature (223 - 273 K) deliquescence (solid to aqueous phase transition) and efflorescence (aqueous to solid phase transition) of three hydration states of CaCl2 (dihydrate, tetrahydrate, hexahydrate). We have found that the deliquescence relative humidity (DRH) increases with increasing hydration state, which is an expected result. Average DRH values over the temperature range studied are 20.0 × 2.6% RH for the dihydrate, 31.8 × 6.3% RH for the tetrahydrate and 60.7 × 1.6% RH for the hexahydrate. Once the aqueous solution has formed, efflorescence (recrystallization) of the salt is kinetically hindered and supersaturated solutions can exist at humidities far below the DRH. Regardless of temperature or initial hydration state of the solid salt, we do not observe efflorescence of the aqueous solutions to occur until single digit RH values are reached. We show here that calcium chloride is at least as deliquescent as many perchlorate salts, and that solutions of calcium chloride are even more difficult to recrystallize once a brine solution has formed. These experimental results will assist with interpretation of observations of deliquescence in the Antarctic Dry Valleys and will help us understand potential liquid water formation on Mars. In addition to formation of brines through melting, deliquescence of salts such as CaCl2 is a reasonable mechanism for formation of aqueous solutions on current Mars.

  11. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...true Applicability; description of the calcium chloride production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory....

  12. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...true Applicability; description of the calcium chloride production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory....

  13. 40 CFR 415.40 - Applicability; description of the calcium chloride production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...false Applicability; description of the calcium chloride production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory....

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...true Applicability; description of the calcium chloride production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory....

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...true Applicability; description of the calcium chloride production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Chloride Production Subcategory § 415.40 Applicability; description of the calcium chloride production subcategory....

  16. POSTHARVEST CALCIUM CHLORIDE DIPS OF WHOLE TOMATO FRUIT REDUCE POSTHARVEST DECAY UNDER COMMERCIAL CONDITIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research showed that mature green tomato fruit dipped 1 to 4 minutes in a 1% CaCl2 solutions before storage had significantly increased peel calcium content and reduced postharvest decay. The present experiments, conducted over 3-day periods (reps), evaluate treatment effectiveness under c...

  17. A Solution NMR Investigation into the Early Events of Amelogenin Nanosphere Self-Assembly Initiated with Sodium Chloride or Calcium Chloride

    PubMed Central

    Buchko, Garry W.; Tarasevich, Barbara J.; Bekhazi, Jacky; Snead, Malcolm L.; Shaw, Wendy J.

    2009-01-01

    Using solution-state NMR spectroscopy, new insights into the early events governing amelogenin supramolecular self-assembly have been identified using sodium chloride and calcium chloride to trigger the association. Two-dimensional 1H–15N HSQC spectra were recorded for 15N- and 13C-labeled murine amelogenin as a function of increasing NaCl and CaCl2 concentration beginning with solution conditions of 2% acetic acid at pH 3.0, where amelogenin was monomeric. Residue specific changes in molecular dynamics, manifested by the reduction in intensity and disappearance of 1H–15N HSQC cross-peaks, were observed with the addition of either salt to the protein. With increasing NaCl concentrations, residues between T21 and R31 near the N-terminus were affected first, suggesting that these residues may initiate amelogenin dimerization, the first step in nanosphere assembly. At higher NaCl concentrations, more residues near the N-terminus (Y12–I51) were affected, and with further additions of NaCl, residues near the C-terminus (L141–T171) began to show a similar change in molecular dynamics. With increasing CaCl2 concentrations, a similar stepwise change in molecular dynamics involving essentially the same set of amelogenin residues was observed. As the concentration of either salt was increased, a concomitant increase in the estimated overall rotational correlation time (?c) was observed, consistent with assembly. Self-assembly into a dimer or trimer was established with dynamic light scattering studies under similar conditions that showed an increase in diameter of the smallest species from 4.1 nm in the absence of salt to ~10 nm in the presence of salt. These results suggest a possible stepwise interaction mechanism, starting with the N-terminus and followed by the C-terminus, leading to amelogenin nanosphere assembly. PMID:19086270

  18. Effect of calcium chloride addition and draining pH on the microstructure and texture of full fat Cheddar cheese during ripening.

    PubMed

    Soodam, Kevany; Ong, Lydia; Powell, Ian B; Kentish, Sandra E; Gras, Sally L

    2015-08-15

    Calcium chloride is commonly added to cheese-milk to improve coagulum formation and to increase cheese yield but high concentrations of calcium ions can have adverse effects. In this study, confocal laser scanning microscopy and cryo-scanning electron microscopy were coupled with textural and chemical analyses to observe microstructural and biochemical changes that occur in cheese during ripening when calcium chloride is added or the draining pH altered. For the cheese prepared with no additional calcium at a draining pH of 6.0, the cheese porosity increased with ripening time and the number of protein vertices in the microscopy images declined, indicative of protein solubilisation. As the amount of CaCl2 added was increased, however, these changes became less significant. Our findings show that calcium chloride addition can be used, together with a lower draining pH, to alter the manufacturing process without significantly impacting on the quality of the mature cheese. PMID:25794728

  19. Reduction of calcium corrosion in thionyl chloride-based electrolytes

    NASA Astrophysics Data System (ADS)

    Bradley, J.; Mitchell, P. J.; Hagan, W. P.; Tuck, C. D. S.

    Concern in respect of the safety of lithium oxyhalide cells has led to a search for alternative anode materials. A well-documented alternative is calcium; but this corrodes more rapidly than does lithium. This corrosion is a fundamental shortcoming of the calcium?thionyl chloride system and must be improved before exploitation is feasible. We have demonstrated that modification of the electrolyte can result in a considerable decrease in the calcium corrosion rate.

  20. Skin injuries afflicting three oil workers following contact with calcium bromide and\\/or calcium chloride

    Microsoft Academic Search

    W. R. Saeed; S. Distante; J. D. Holmes; P. S. Kolhe

    1997-01-01

    Calcium bromide brine is a highly concentrated aqueous solution of calcium bromide and calcium chloride. It is used extensively in the oil industry. This solution and its components are recognized as causes of skin injury and information is available from the manufacturers on their safe use and handling. Two patients who were injured following unprotected skin exposure to this solution

  1. Fermentation of cucumbers brined with calcium chloride instead of sodium chloride

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Generation of waste water containing sodium chloride from cucumber fermentation tank yards could be eliminated if cucumbers were fermented in brines that did not contain this salt. To determine if this is feasible, cucumbers were fermented in brines that contained only calcium chloride to maintain f...

  2. Preparation and Characterization of a Calcium Phosphate Ceramic for the Immobilization of Chloride-containing Intermediate Level Waste

    SciTech Connect

    Metcalfe, Brian; Donald, Ian W.; Scheele, Randall D.; Strachan, Denis M.

    2003-12-01

    Attention has recently been given to the immobilization of special categories of radioactive wastes, some of which contain high concentrations of actinide chlorides. Although vitrification in phosphate glass has been proposed, this was rejected because of the high losses of chloride. On the basis of non-radioactive and, more recently, radioactive studies, we have shown that calcium phosphate is an effective host for immobilizing the chloride constituents [1]. In this instance, the chlorine is retained as chloride, rather than evolved as a chlorine-bearing gas. The immobilized product is in the form of a free-flowing, non-hygroscopic powder, in which the chlorides are chemically combined within the mineral phases chlorapatite [Ca5(PO4)3Cl] and spodiosite [Ca2(PO4)Cl]. Data from studies on non-radioactive simulated waste consisting of a mixture of CaCl2 and SmCl3, and radioactive simulated waste composed of CaCl2 with PuCl3 or PuCl3 and AmCl3, are presented and compared. The XRD data confirm the presence of chlorapatite and spodiosite in the non-radioactive and radioactive materials. The durability of all specimens was measured with a modified MCC-1 test. Releases of Cl after 28 days were 1.6 x 10-3 g m-2 for the non-radioactive specimens and 7 x 10-3 g m-2 for the Pu-bearing specimens. Releases of Ca after 28 days were 0.3 x 10-3 and 2.0 x 10-3 g m-2 for the non-radioactive composition and the Pu composition, respectively, whilst release of Pu from the radioactive specimens was lower for the mixed Pu/Am specimen at 1.2 x 10-5g m-2. The release of Am from the mixed Pu/Am composition was exceptionally low at 2.4 x 10-7 g m-2. Overall, the release rate data suggest that the ceramics dissolve congruently, followed by precipitation of Sm, Pu and Am as less soluble phases, possibly oxides or phosphates. The differences in behaviour noted between non-radioactive and radioactive specimens are interpreted in terms of the crystal chemistry of the individual systems.

  3. Cathode performance improvement in calcium-thionyl chloride cells

    NASA Astrophysics Data System (ADS)

    Walker, C. W., Jr.; Wade, W. L., Jr.; Binder, M.; Gilman, S.

    1986-08-01

    Carbon cathode performance in calcium-thionyl chloride cells was markedly improved with a cathode comprised of a mixture of high and low surface area carbon blacks. Addition of sulfur dioxide gas to the electrolyte further enhanced cathode performance and electrolyte conductivity. Load potentials and cathode life were nearly equal to that of the analogous lithium based system. The advantage of the calcium based system is its potential for greater safety.

  4. New uses for calcium chloride solution as a mounting medium.

    PubMed

    Herr, J M

    1992-01-01

    Fresh cross sections of stems (Psilotum nudum, Coleus blumei, and Pelargonium peltatum) and roots (Setcreasea purpurea) 120 microns thick were fixed in FPA50 (formalin: propionic acid: 50% ethanol, 5:5:90, v/v) for 24 hr and stored in 70% ethanol. The sections were transferred to water and then to 1% phloroglucin in 20% calcium chloride solution plus either hydrochloric, nitric, or lactic acid in the following ratios of phloroglucin-CaCl2 solution:acid: 25:4, 20:2, or 15:5. The sections were mounted on slides either in one of the three mixtures or in fresh 20% calcium chloride solution. A rapid reaction of the acid-phloroglucin with lignin produced a deep red color in tracheary elements and an orange-red color in sclerenchyma. Fixed and stored leaf pieces from Nymphaea odorata were autoclaved in lactic acid, washed in two changes of 95% ethanol, transferred to water, and treated with the three acid-phloroglucin-calcium chloride mixtures. The abundant astrosclereids stained an orange-red color similar to that of sclerenchyma in the sections. In addition, a new method is reported for specifically staining lignified tissues. When sections or leaf pieces are stained in aqueous 0.05% toluidine blue O, then placed in 20% calcium chloride solution, all tissues destain except those with lignified or partially lignified cell walls. Thus, toluidine blue O applied as described becomes a reliable specific test for lignin comparable to the acid-phloroglucin test. PMID:1377501

  5. Cardioprotective activity of alcoholic extract of Tinospora cordifolia (Willd.) Miers in calcium chloride-induced cardiac arrhythmia in rats

    PubMed Central

    Sharma, Ashish Kumar; Kishore, Kunal; Sharma, Divya; Srinivasan, B.P; Agarwal, Shyam Sunder; Sharma, Ashok; Singh, Santosh Kumar; Gaur, Samir; Jatav, Vijay Singh

    2011-01-01

    The present study investigated the antiarrhythmic activity of alcoholic extract of Tinospora cordifolia (T. cordifolia) in CaCl2 induced arrhythmia. CaCl2 (25 mg/kg) was administered by intravenous infusion (iv) to produce arrhythmia in rats. The animals were then treated with T. cordifolia extract (150, 250, and 450 mg/kg) and verapamil (5 mg/kg,iv). Lead II electrocardiogram was monitored. Plasma calcium, sodium and potassium levels were measured. In CaCl2 induced arrhythmia, heart rate was decreased by 41.10%, T. cordifolia at 150, 300, and 450 mg/kg decreased the heart rate by 26.30%, 29.16%, and 38.29%, respectively, and verapamil reduced the heart rate by 9.70% compared to the normal group. The PQRST waves were normalized and atrial and ventricular fibrillation was controlled in rats treated with verapamil and T. cordifolia. CaCl2 increased calcium and sodium levels and decreased potassium levels in blood. T. cordifolia dose-dependently decreased calcium and sodium levels and increased potassium levels. Hence, T. cordifolia can be used in antiarrhythmic clinical settings and beneficial in atrial and ventricular fibrillation and flutter and may be indicated in ventricular tachyarrhythmia. PMID:23554702

  6. Influence of EDTA and citrate on physicochemical properties of whey protein-stabilized oil-in-water emulsions containing CaCl2.

    PubMed

    Keowmaneechai, E; McClements, D J

    2002-11-20

    The influence of chelating agents (disodium ethylenediaminetetraacetate (EDTA) and sodium citrate) on the physicochemical properties of whey protein isolate (WPI)-stabilized oil-in-water emulsions containing calcium chloride was determined. The calcium-binding characteristics of EDTA and citrate at 30 degrees C were characterized in aqueous solutions (20 mM Tris buffer, pH 7.0) by isothermal titration calorimetry (ITC). EDTA and citrate both bound calcium ions in a 1:1 ratio, but EDTA had a much higher binding constant. Oil-in-water emulsions (pH 7.0) were prepared containing 6.94% (w/v) soybean oil, 0.35% (w/v) WPI, 0.02% (w/v) sodium azide, 20 mM Tris buffer, 10 mM CaCl(2), and 0-40 mM chelating agent. The particle size, apparent viscosity, creaming stability, free calcium concentration, and particle surface potential of the emulsions were measured. The chelating agents reduced or prevented droplet aggregation in the emulsions. When they were present above a certain concentration (>3.5 mM EDTA or >5 mM citrate), droplet aggregation was prevented. The reduction of aggregation was indicated by decreases in particle size, shear-thinning behavior, apparent viscosity, and creaming. Emulsions containing chelating agents had lower free calcium concentrations and more negatively charged droplets, indicating that the chelating agents improved emulsion stability by binding calcium ions. EDTA could be used at lower concentrations than citrate because of its higher calcium ion binding constant. PMID:12428974

  7. Advanced calcium-thionyl chloride high-power battery

    NASA Astrophysics Data System (ADS)

    Peled, Emanuel

    1990-08-01

    In this phase it is demonstrated that Ca/SrX2 + 7 or 20 percent SO2-TC cells (A7 and A20 types) can deliver at RT up to 5.5 Ah at low rates and 4.4 Ah at 0.9 A. These cells have 10 to 80 percent more capacity than have commercial Li-TC and Li-SO2 wound c-size cells. The improved A7 and A20 types cells lost almost no capacity after 4 to 5 weeks of storage at 70 C. The A20 type cell generates less heat at 20 C under OCV conditions than equivalent Li/TC cells, having the same electrode area, i.e., it has a longer shelf life. The addition of P40 additive to SrX2 + TC + SO2 solutions decrease further the corrosion rate of calcium. The lowest corrosion rate found for solutions containing 20 percent SO2 + 0.3 percent P40. Formulation of the SrX2-TC electrolyte with 20 percent SO2 and 0.3 percent P40 (A20S type cell) found to have the following advantages: it increases shelf life, it increases load voltage and Faradaic efficiency. A preliminary specification of A20S type Ca-TC cell is enclosed. The improved shelf-life of calcium in BaX2/TC solutions as compared to CaX2/TC solutions results mainly for the difference in the solubility or reactivity of the CaO film in those two solutions. In CaX2/TC solutions the oxide dissolves leaving the calcium with a CaCl2 layer which does not provide the metal with good protection. In BaX2/TC solutions, on the native CaO layer a BaCl2+AlCl3 or Al2O3 layer is formed. This BaCl3+AlCl3+Al2O3 layer does not form when the oxide is missing from the surface.

  8. Heat stability of milk supplemented with calcium chloride.

    PubMed

    On-Nom, N; Grandison, A S; Lewis, M J

    2012-04-01

    Calcium chloride (0-25 mM) was added to skim milk powder that was reconstituted to 9% total solids. Heat stability was evaluated between 60 and 120°C for different times by observing whether samples had coagulated, and by measuring the amount of sediment and residual protein in the centrifuged supernatant. Milk samples were also dialyzed during their respective heat treatments to recover the soluble phase at different temperatures to measure pH and ionic calcium. The transition conditions between good and poor heat stability were established for different calcium chloride concentrations and temperatures. As temperature increased, coagulation occurred at lower levels of added calcium chloride. The transition was quite distinct at higher temperatures but less so at lower temperatures; it was initiated by an increase in sediment formation before a firm coagulum was formed. Both pH and ionic calcium decreased in dialysates as temperature increased. No coagulation was observed if Ca(2+) was <0.5 mM and pH was >6.3 in dialysates taken at their respective coagulation temperatures. Being able to measure pH and ionic calcium at high temperatures will allow better understanding of factors affecting heat stability. Electrophoresis of the supernatants permitted identification of the protein fractions participating in the coagulation process. When coagulation was observed below 80°C, substantial amounts of undenatured ?-lactoglobulin and ?-lactalbumin were found in the supernatant, as well as some soluble casein fractions. All the major whey protein and casein fractions were found in the sediment. PMID:22459810

  9. The effects of calcium hydroxide on hydrogen chloride emission characteristics during a simulated densified refuse-derived fuel combustion process.

    PubMed

    Chiang, Kung-Yuh; Jih, Jer-Chyuan; Lin, Kae-Long

    2008-08-30

    This study investigated the effects of different calcium hydroxide (Ca(OH)(2)) addition methods on the potential for hydrogen chloride (HCl) formation in a simulated densified refuse-derived fuel (RDF-5) with single metal combustion system. These experiments were conducted at 850 degrees C with the Ca(OH)(2) spiked in the RDF-5 production or injection in the flue gas treatment system. The results indicated that the potential for HCl formation was decreased significantly by Ca(OH)(2) spiked in the RDF-5 production or injection in the flue gas treatment system. However, the Ca(OH)(2) injection method in the flue gas for HCl emission reduction was better than other method. According to the relationship between the HCl emission and amount of Ca(OH)(2) injected or spiked, it is interesting to find that when the Ca(OH)(2) injected or spiked ranged from 0% to 5%, the potential for HCl formation in the single metal combustion system decreases significantly with increasing Ca(OH)(2) injected or spiked ratio. A corresponding increase in the amount of CaCl(2) partitioned to the fly ash was observed. However, with the ratio of Ca(OH)(2) higher than 5%, the amount of HCl formation showed that no further significant variation occurred with increasing Ca(OH)(2) spiked ratio. PMID:18272287

  10. Uptake of chloride and carbonate ions by calcium monosulfoaluminate hydrate

    SciTech Connect

    Mesbah, Adel [Commissariat a l'Energie Atomique et aux Energies Alternatives, CEA DEN/DTCD/SPDE, F-30207 Bagnols sur Ceze (France); Clermont Universite, ENSCCF, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); Cau-dit-Coumes, Celine, E-mail: celine.cau-dit-coumes@cea.fr [Commissariat a l'Energie Atomique et aux Energies Alternatives, CEA DEN/DTCD/SPDE, F-30207 Bagnols sur Ceze (France); Renaudin, Guillaume [Clermont Universite, ENSCCF, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, F-63177 Aubiere (France); Frizon, Fabien [Commissariat a l'Energie Atomique et aux Energies Alternatives, CEA DEN/DTCD/SPDE, F-30207 Bagnols sur Ceze (France); Leroux, Fabrice [Clermont Universite, Universite Blaise Pascal, Laboratoire des Materiaux Inorganiques, BP 10448, F-63000 Clermont-Ferrand (France); CNRS, UMR 6002, F-63177 Aubiere (France)

    2012-08-15

    Decommissioning of old nuclear reactors may produce waste streams containing chlorides and carbonates, including radioactive {sup 36}Cl{sup -} and {sup 14}CO{sub 3}{sup 2-}. Their insolubilization by calcium monosulfoaluminate hydrate was investigated. Carbonates were readily depleted from the solution, giving at thermodynamic equilibrium monocarboaluminate, monocarboaluminate + calcite, or calcite only, depending on the initial ratio between the anion and calcium monosulfoaluminate hydrate. Chloride ions reacted more slowly and were precipitated as Kuzel's salt, Kuzel's and Friedel's salts, or Friedel's salt only. Rietveld refinement of X-Ray powder diffraction patterns was successfully used to quantify the phase distributions, which were compared to thermodynamic calculations. Moreover, analysing the lattice parameters of Kuzel's salt as a function of its chloride content showed the occurrence of a restricted solid solution towards the sulfate side with general formula 3CaO{center_dot}Al{sub 2}O{sub 3}{center_dot}xCaCl{sub 2}{center_dot}(1 - x)CaSO{sub 4}{center_dot}(12 - 2x){center_dot}H{sub 2}O (0.36 {<=} x {<=} 0.50).

  11. Chloride- and alkali-containing calcium phosphates as basic materials to prepare calcium phosphate cements.

    PubMed

    Bermúdez, O; Boltong, M G; Driessens, F C; Ginebra, M P; Fernández, E; Planell, J A

    1994-10-01

    Combinations of an alkali-containing calcium phosphate-like rhenanite, sodium whitlockite or calcium potassium phosphate and a chloride-containing calcium phosphate-like spodiosite or chloroapatite with or without additions of other calcium phosphates like monocalcium phosphate monohydrate, dicalcium phosphate or dicalcium phosphate dihydrate were made and mixed with water into pastes. The setting time of these pastes was determined. After soaking for a day in Ringer's solution at 37 degrees C the compressive strength and the diametral tensile strength were determined. Two of the combinations tried in this study resulted in the formation of cements at room temperature. One cement was of the type dicalcium phosphate, whereas the other gave octocalcium phosphate as the solid reaction product. The byproducts formed were an aqueous solution of NaCl and one of K2HPO4, respectively. Applications for bone repair and augmentation are envisaged. PMID:7841290

  12. Repassivation Potential of Alloy 22 in Sodium and Calcium Chloride Brines

    SciTech Connect

    Rebak, R B; Ilevbare, G O; Carranza, R M

    2007-08-11

    A comprehensive matrix of 60 tests was designed to explore the effect of calcium chloride vs. sodium chloride and the ratio R of nitrate concentration over chloride concentration on the repassivation potential of Alloy 22. Tests were conducted using the cyclic potentiodynamic polarization (CPP) technique at 75 C and at 90 C. Results show that at a ratio R of 0.18 and higher nitrate was able to inhibit the crevice corrosion in Alloy 22 induced by chloride. Current results fail to show in a consistent way a different effect on the repassivation potential of Alloy 22 for calcium chloride solutions than for sodium chloride solutions.

  13. Removal of chloride from MSWI fly ash.

    PubMed

    Chen, Wei-Sheng; Chang, Fang-Chih; Shen, Yun-Hwei; Tsai, Min-Shing; Ko, Chun-Han

    2012-10-30

    The high levels of alkali chloride and soluble metal salts present in MSWI fly ash is worth noting for their impact on the environment. In addition, the recycling or reuse of fly ash has become an issue because of limited landfill space. The chloride content in fly ash limits its application as basis for construction materials. Water-soluble chlorides such as potassium chloride (KCl), sodium chloride (NaCl), and calcium chloride hydrate (CaCl(2) · 2H(2)O) in fly ash are easily washed away. However, calcium chloride hydroxide (Ca(OH)Cl) might not be easy to leach away at room temperature. The roasting and washing-flushing processes were applied to remove chloride content in this study. Additionally, air and CO(2) were introduced into the washing process to neutralize the hazardous nature of chlorides. In comparison with the water flushing process, the roasting process is more efficient in reducing the process of solid-liquid separation and drying for the reuse of Cl-removed fly ash particles. In several roasting experiments, the removal of chloride content from fly ash at 1050°C for 3h showed the best results (83% chloride removal efficiency). At a solid to liquid ratio of 1:10 the water-flushing process can almost totally remove water-soluble chloride (97% chloride removal efficiency). Analyses of mineralogical change also prove the efficiency of the fly ash roasting and washing mechanisms for chloride removal. PMID:22947185

  14. Soil stabilization using optimum quantity of calcium chloride with Class F fly ash 

    E-print Network

    Choi, Hyung Jun

    2006-10-30

    and both Class C fly ash and Class F fly ash. Mix design was fixed at 1.3% and 1.7% calcium chloride and 5% and 10% fly ash with crushed limestone base material. Throughout previous studies, recommended mix design was 1.7% calcium chloride filter cake...

  15. Soil stabilization using optimum quantity of calcium chloride with Class F fly ash

    E-print Network

    Choi, Hyung Jun

    2006-10-30

    and both Class C fly ash and Class F fly ash. Mix design was fixed at 1.3% and 1.7% calcium chloride and 5% and 10% fly ash with crushed limestone base material. Throughout previous studies, recommended mix design was 1.7% calcium chloride filter cake...

  16. Cobalt(II) Chloride Complex Formation in Acetamide–Calcium Nitrate Tetrahydrate Melts

    Microsoft Academic Search

    Jelena Savovi?; Ružica Nikoli?; Dragan Veselinovi?

    2004-01-01

    The absorption spectra of Co(II) chloride complexes, containing variable concentrations of chloride ligand, in a molten mixture of 80 mol% acetamide–20 mol% calcium nitrate tetrahydrate, were studied at 313, 333, 353, and 363 K, in the wavelength range 400-800 nm. The melt contains three possible ligands (CH3CONH2, H2O, and NO3-) for competition with added chloride ligand. Addition of chloride caused

  17. Advanced calcium-thionyl chloride high-power battery

    NASA Astrophysics Data System (ADS)

    Peled, Emanuel

    1989-07-01

    Recently, a breakthrough was made in the development of two advanced Ca-TC systems which have much better electric storage properties than the state-of-the-art Ca-SOC cell. This was done by replacing the CaX2 (X=AlCl4) electrolyte by SrX2 (type A), or BaX2 (type B). The project's goals are to gain a better understanding of the electrochemistry of the advanced systems and to establish their safety and performance. In this phase, the cell performance was improved significantly. An improved C-size A7 type cell delivers 4.4 Ah at 0.9 A rate and room temperature which is 50 percent more than similar size commercial lithium cells have. The SAFT LSH14 lithium-thionyl chloride and the Duracell L028SH lithium-SO2 cells have at this rate only 2.9 and 2.7 Ah respectively. During one year of storage at room temperature the heat generation rate of 150 sq cm C-size A7 type cells decreased to a level of 60 to 70 microwatts. A cell lost 0.3 Ah after this storage period. The effect of several parameters on the corrosion rate of calcium in TC solutions was studied. Preliminary results indicate: SO2 decreases corrosion, there is no stress corrosion due to twisting of Ca foils, the native oxide layer helps in preventing corrosion, Ca foils as received contain only about 90 percent metallic calcium. The role native calcium oxide layer plays depends on the type of electrolyte used.

  18. Heat storage material comprising calcium chloride-hexahydrate and a nucleating agent

    SciTech Connect

    Gawron, K.; Schroder, J.

    1980-02-19

    The utility of calcium chloride-hexahydrate as a heat storage material is improved when barium carbonate, strontium carbonate, barium fluoride, barium fluoride-hydrofluoride and/or strontium fluoride is used as a nucleating agent to prevent supercooling.

  19. Organoaqueous calcium chloride electrolytes for capacitive charge storage in carbon nanotubes at sub-zero-temperatures.

    PubMed

    Gao, Yun; Qin, Zhanbin; Guan, Li; Wang, Xiaomian; Chen, George Z

    2015-06-23

    Solutions of calcium chloride in mixed water and formamide are excellent electrolytes for capacitive charge storage in partially oxidised carbon nanotubes at unprecedented sub-zero-temperatures (e.g. 67% capacitance retention at -60 °C). PMID:26060845

  20. Evaluation of calcium chloride and ammonium thiosulfate as ammonia volatilization inhibitors for surface-applied urea 

    E-print Network

    Sloan, John J.

    1989-01-01

    EVALUATION OF CALCIUM CHLORIDE AND AMMONIUM THIOSULFATE AS AMMONIA VOLATILIZATION INHIBITORS FOR SURFACE-APPLIED UREA A Thesis by JOHN J. SLOAN Submitted to the Office of Graduate Studies of Texas AgcM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1989 Ma!or Subject: Soil Science EVALUATION OF CALCIUM CHLORIDE AND AMMONIUM THIOSULFATE AS AMMONIA VOLATILIZATION INHIBITORS FOR SURFACE-APPLIED UREA A Thesis by JOHN J. SLOAN Approved as to style...

  1. CaCl2, Bisoxazoline, and Malonate: A Protocol for an Asymmetric Michael Reaction.

    PubMed

    Lippur, Kristin; Kaabel, Sandra; Järving, Ivar; Rissanen, Kari; Kanger, Tõnis

    2015-06-19

    A mild protocol for the asymmetric Michael addition of dimethyl malonate to various ?,?-unsaturated carbonyl compounds was developed. The salient feature of this methodology is that a cheap and environmentally friendly Lewis acid, CaCl2, was used as a catalyst. An aminoindanol- and pyridine-derived ligand provided in the presence of CaCl2 Michael adducts in moderate to high enantioselectivities. The scope of the reaction was demonstrated. PMID:26035234

  2. Glucose stimulates calcium-activated chloride secretion in small intestinal cells.

    PubMed

    Yin, Liangjie; Vijaygopal, Pooja; MacGregor, Gordon G; Menon, Rejeesh; Ranganathan, Perungavur; Prabhakaran, Sreekala; Zhang, Lurong; Zhang, Mei; Binder, Henry J; Okunieff, Paul; Vidyasagar, Sadasivan

    2014-04-01

    The sodium-coupled glucose transporter-1 (SGLT1)-based oral rehydration solution (ORS) used in the management of acute diarrhea does not substantially reduce stool output, despite the fact that glucose stimulates the absorption of sodium and water. To explain this phenomenon, we investigated the possibility that glucose might also stimulate anion secretion. Transepithelial electrical measurements and isotope flux measurements in Ussing chambers were used to study the effect of glucose on active chloride and fluid secretion in mouse small intestinal cells and human Caco-2 cells. Confocal fluorescence laser microscopy and immunohistochemistry measured intracellular changes in calcium, sodium-glucose linked transporter, and calcium-activated chloride channel (anoctamin 1) expression. In addition to enhancing active sodium absorption, glucose increased intracellular calcium and stimulated electrogenic chloride secretion. Calcium imaging studies showed increased intracellular calcium when intestinal cells were exposed to glucose. Niflumic acid, but not glibenclamide, inhibited glucose-stimulated chloride secretion in mouse small intestines and in Caco-2 cells. Glucose-stimulated chloride secretion was not seen in ileal tissues incubated with the intracellular calcium chelater BAPTA-AM and the sodium-potassium-2 chloride cotransporter 1 (NKCC1) blocker bumetanide. These observations establish that glucose not only stimulates active Na absorption, a well-established phenomenon, but also induces a Ca-activated chloride secretion. This may explain the failure of glucose-based ORS to markedly reduce stool output in acute diarrhea. These results have immediate potential to improve the treatment outcomes for acute and/or chronic diarrheal diseases by replacing glucose with compounds that do not stimulate chloride secretion. PMID:24477233

  3. 43 CFR 3511.11 - If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false If I am mining calcium chloride, may I obtain a noncompetitive...Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive...chloride? Yes. If you are producing calcium chloride in paying quantities from an...

  4. 43 CFR 3511.11 - If I am mining calcium chloride, may I obtain a noncompetitive mineral lease to produce the...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false If I am mining calcium chloride, may I obtain a noncompetitive...Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive...chloride? Yes. If you are producing calcium chloride in paying quantities from an...

  5. Calcium-activated chloride channels in the apical region of mouse vomeronasal sensory neurons

    PubMed Central

    Dibattista, Michele; Amjad, Asma; Maurya, Devendra Kumar; Sagheddu, Claudia; Montani, Giorgia; Tirindelli, Roberto

    2012-01-01

    The rodent vomeronasal organ plays a crucial role in several social behaviors. Detection of pheromones or other emitted signaling molecules occurs in the dendritic microvilli of vomeronasal sensory neurons, where the binding of molecules to vomeronasal receptors leads to the influx of sodium and calcium ions mainly through the transient receptor potential canonical 2 (TRPC2) channel. To investigate the physiological role played by the increase in intracellular calcium concentration in the apical region of these neurons, we produced localized, rapid, and reproducible increases in calcium concentration with flash photolysis of caged calcium and measured calcium-activated currents with the whole cell voltage-clamp technique. On average, a large inward calcium-activated current of ?261 pA was measured at ?50 mV, rising with a time constant of 13 ms. Ion substitution experiments showed that this current is anion selective. Moreover, the chloride channel blockers niflumic acid and 4,4?-diisothiocyanatostilbene-2,2?-disulfonic acid partially inhibited the calcium-activated current. These results directly demonstrate that a large chloride current can be activated by calcium in the apical region of mouse vomeronasal sensory neurons. Furthermore, we showed by immunohistochemistry that the calcium-activated chloride channels TMEM16A/anoctamin1 and TMEM16B/anoctamin2 are present in the apical layer of the vomeronasal epithelium, where they largely colocalize with the TRPC2 transduction channel. Immunocytochemistry on isolated vomeronasal sensory neurons showed that TMEM16A and TMEM16B coexpress in the neuronal microvilli. Therefore, we conclude that microvilli of mouse vomeronasal sensory neurons have a high density of calcium-activated chloride channels that may play an important role in vomeronasal transduction. PMID:22732308

  6. Composite adsorbent of CaCl 2 and expanded graphite for adsorption ice maker on fishing boats

    Microsoft Academic Search

    K. Wang; J. Y. Wu; R. Z. Wang; L. W. Wang

    2006-01-01

    Adsorption performances and thermal conductivity were tested for three types of adsorbent: Pure CaCl2 powder, simple composite adsorbent and consolidated composite adsorbent. The simple composite adsorbents show better adsorption performance because the additive of expanded graphite in CaCl2 powder has restrained the agglomeration phenomenon in adsorption process and improved the adsorption performance of CaCl2. The consolidated composite adsorbent are suitable

  7. The calcium-activated chloride channel Anoctamin 1 contributes to the regulation of renal function.

    PubMed

    Faria, Diana; Rock, Jason R; Romao, Ana M; Schweda, Frank; Bandulik, Sascha; Witzgall, Ralph; Schlatter, Eberhard; Heitzmann, Dirk; Pavenstädt, Hermann; Herrmann, Edwin; Kunzelmann, Karl; Schreiber, Rainer

    2014-06-01

    The role of calcium-activated chloride channels for renal function is unknown. By immunohistochemistry we demonstrate dominant expression of the recently identified calcium-activated chloride channels, Anoctamin 1 (Ano1, TMEM16A) in human and mouse proximal tubular epithelial (PTE) cells, with some expression in podocytes and other tubular segments. Ano1-null mice had proteinuria and numerous large reabsorption vesicles in PTE cells. Selective knockout of Ano1 in podocytes (Ano1-/-/Nphs2-Cre) did not impair renal function, whereas tubular knockout in Ano1-/-/Ksp-Cre mice increased urine protein excretion and decreased urine electrolyte concentrations. Purinergic stimulation activated calcium-dependent chloride currents in isolated proximal tubule epithelial cells from wild-type but not from Ano1-/-/Ksp-Cre mice. Ano1 currents were activated by acidic pH, suggesting parallel stimulation of Ano1 chloride secretion with activation of the proton-ATPase. Lack of calcium-dependent chloride secretion in cells from Ano1-/-/Ksp-Cre mice was paralleled by attenuated proton secretion and reduced endosomal acidification, which compromised proximal tubular albumin uptake. Tubular knockout of Ano1 enhanced serum renin and aldosterone concentrations, probably leading to enhanced compensatory distal tubular reabsorption, thus maintaining normal blood pressure levels. Thus, Ano1 has a role in proximal tubular proton secretion and protein reabsorption. The results correspond to regulation of the proton-ATPase by the Ano1-homolog Ist2 in yeast. PMID:24476694

  8. Review of the calcium thionyl chloride electrochemical system. Technical report, May 1986-November 1990

    SciTech Connect

    Walker Jr, C.W.

    1991-04-01

    Citing work from the open literature and from Government-sponsored contractual efforts, research on the calcium thionyl chloride electrochemical system is reviewed. Progress has been made toward enhancing the performance at 25[degree]C by adding sulfur dioxide to the electrolyte, and by using cathodes comprised of a blend of high- and low-surface area carbons. Sulfur dioxide raised electrolyte conductivity and improved low-temperature (-30[degree]C) performance; still, low-temperature capacity remains poor. With strontium tetrachloroaluminate salt in the electrolyte, the film that formed on calcium was altered, which reduced rapid corrosion of calcium effectively, especially when used in conjunction with sulfur dioxide. With careful engineering, this may be a viable system for special applications.... Calcium, Thionyl chloride, Corrosion protection, Low-temperature performance.

  9. Effects of Dietary Sodium Bicarbonate and Calcium Chloride on Physiological Responses of Lactating Dairy Cows in Hot Weather

    Microsoft Academic Search

    A. Escobosa; C. E. Coppock; L. D. Rowe Jr; W. L. Jenkins; C. E. Gates

    1984-01-01

    Twenty-four lactating cows were as- signed randomly to three treatments to evaluate responses to large differences of dietary sodium and chloride. Treatments were corn-cottonseed meal-corn silage based complete rations with either: 1) .23% sodium chloride (control), 2) control plus 2.28% calcium chloride, or 3) control plus 1.70% sodium bicarbonate.

  10. Improved control of anthracnose rot in loquat fruit by a combination treatment of Pichia membranifaciens with CaCl(2).

    PubMed

    Cao, Shifeng; Zheng, Yonghua; Tang, Shuangshuang; Wang, Kaituo

    2008-08-15

    The beneficial effect of 2% CaCl(2) (w/v) on the antagonistic yeast Pichia membranifaciens for control of anthracnose rot caused by Colletotrichum acutatum in postharvest loquat fruit (Eriobotrya japonica L.) and the possible mechanisms involved were investigated. The results showed that treatment with P. membranifaciens at 1x10(8) CFU ml(-1) or 2% CaCl(2) alone both resulted in significantly smaller lesion diameter and lower disease incidence of anthracnose rot on loquat fruit wounds compared with the controls. The biocontrol activity of P. membranifaciens on the disease was enhanced by the addition of 2% CaCl(2), the combined treatment of P. membranifaciens with CaCl(2) resulted in a remarkably improved control of the disease in comparison with the treatment of P. membranifaciens or CaCl(2) alone. P. membranifaciens in combination with CaCl(2) induced higher activities of two defense-related enzymes chitinase and beta-1,3-glucanase in loquat fruit than applying the yeast or CaCl(2) alone. The in vitro experiment showed that the addition of 2% CaCl(2) in the suspensions of P. membranifaciens significantly inhibited spore germination and germ tube elongation of C. acutatum than the yeast or CaCl(2) alone. However, adding CaCl(2) did not significantly influence the population of P. membranifaciens in NYDB medium or fruit wounds. These results suggest that CaCl(2) could improve the biocontrol activity of P. membranifaciens on anthracnose rot in loquat fruit. It is postulated that the improved control of the disease is directly because of the higher inhibitory effect on pathogen growth and indirectly because of the enhanced disease resistance in loquat fruit by the combination treatment. PMID:18590937

  11. Consumer acceptability of cucumber pickles produced by fermentation in calcium chloride brine for reduced environmental impact

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fermentation of cucumbers in calcium chloride brine is proposed as an environmentally-friendly alternative to traditional, high salt fermentations. The objective of this research was to determine whether consumer acceptability of pickle products will be impacted by fermentation and storage of cucumb...

  12. Fresh-cut cantaloupe: effects of CaCl2 dips and heat treatments on firmness and metabolic activity

    Microsoft Academic Search

    Irene Luna-Guzman; Marita Cantwell; Diane M. Barrett

    Calcium chloride (1-5%) dips were applied to melon cylinders taken from commercially ripe (3:4 to full slip) cantaloupe melons for 1-5 min. A wound response was observed after cutting, and CO2 production was higher in untreated samples than in calcium treated and intact fruit. Dip time did not significantly effect respiration rate. Application of calcium dips at any temperature resulted

  13. Reference Raman Spectra of CaCl2.nH2O Solids (n= 0, 2, 4, 6).

    NASA Astrophysics Data System (ADS)

    Martinez-Uriarte, L.; Dubessy, J.; Bihannic, I.; Boulet, P.; Robert, P.

    2014-06-01

    Reference Raman spectra of CaCl_2.nH_2O crystals (100-3800 cm^-1), identified by XRD, are given with a preliminary band assignment. This will help fluid inclusionists for the interpretation of phase changes in CaCl_2-rich aqueous fluid inclusions.

  14. Preserved frontal lobe oxygenation following calcium chloride for treatment of anesthesia-induced hypotension

    PubMed Central

    Kitchen, Carl-Christian; Nissen, Peter; Secher, Niels H.; Nielsen, Henning B.

    2014-01-01

    Vasopressor agents may affect cerebral oxygenation (rScO2) as determined by near-infrared spectroscopy on the forehead. This case series evaluated the effect of calcium chloride vs. ? and ?-adrenergic receptor agonists on rScO2 in patients (n = 47) undergoing surgery during i.v. anesthesia. Mean arterial pressure (MAP) and cardiac output (CO) were assessed by Model-flow® and ephedrine (55 ± 3 vs. 74 ± 9 mmHg; 10 mg, n = 9), phenylephrine (51 ± 5 vs. 78 ± 9 mmHg, 0.1 mg, n = 11), adrenaline (53 ± 3 vs. 72 ± 11 mmHg; 1–2 ?g, n = 6), noradrenaline (53 ± 5 vs. 72 ± 12 mmHg; 2–4 ?g, n = 11), and calcium chloride (49 ± 7 vs. 57 ± 16 mmHg; 5 mmol, n = 10) increased MAP (all P < 0.05). CO increased with ephedrine (4.3 ± 0.9 vs. 5.3 ± 1.2, P < 0.05) and adrenaline (4.7 ± 1.2 vs. 5.9 ± 1.1 l/min; P = 0.07) but was not significantly affected by phenylephrine (3.9 ± 0.7 vs. 3.6 ± 1.0 l/min), noradrenaline (3.8 ± 1.2 vs. 3.7 ± 0.7 l/min), or calcium chloride (4.0 ± 1.4 vs. 4.1 ± 1.5 l/min). Following administration of ?-adrenergic agents and calcium chloride rScO2 was preserved while after administration of ?-adrenergic drugs rScO2 was reduced by app. 2% (P < 0.05). Following ?-adrenergic drugs to treat anesthesia-induced hypotension tissue oxygenation is reduced while the use of ?-adrenergic agonists and calcium chloride preserve tissue oxygenation. PMID:25374543

  15. Solar heating and cooling with the CaCl2-CH3OH chemical heat pump

    NASA Astrophysics Data System (ADS)

    Offenhartz, P. O.

    1982-03-01

    A chemical heat pump based on the reaction of calcium chloride and methanol is being designed and optimized for solar heating and air conditioning, primarily for the residential and light commercial market. The performance requirements for this application are quite stringent. For example, to minimize maintenance, a cooling tower should not be used, and the solar collectors should be fixed rooftop flat plates or evacuated tubes. The chiller should be capable of reaching 45 F on a 95 F day in order to provide effective dehumidification. Energy storage for late afternoon and early evening cooling, as well as night time winter heating, must be provided.

  16. Interactive effects of sodium chloride, sodium sulfate, calcium sulfate, and calcium chloride on snapbean growth, photosynthesis, and ion uptake

    Microsoft Academic Search

    S. Awada; W. F. Campbell; L. M. Dudley; J. J. Jurinak; M. A. Khan

    1995-01-01

    Excessive sodium (Na) accumulation in soil, which can be a problem for production agriculture in arid and semiarid regions, may be ameliorated by calcium (Ca). The mechanisms of Ca amelioration of Na stress in plants have received much more attention than has the effect of the anion of the Ca salt. Our objective was to determine the relative effects of

  17. A comprehensive search for calcium binding sites critical for TMEM16A calcium-activated chloride channel activity

    PubMed Central

    Tien, Jason; Peters, Christian J; Wong, Xiu Ming; Cheng, Tong; Jan, Yuh Nung; Jan, Lily Yeh; Yang, Huanghe

    2014-01-01

    TMEM16A forms calcium-activated chloride channels (CaCCs) that regulate physiological processes such as the secretions of airway epithelia and exocrine glands, the contraction of smooth muscles, and the excitability of neurons. Notwithstanding intense interest in the mechanism behind TMEM16A-CaCC calcium-dependent gating, comprehensive surveys to identify and characterize potential calcium sensors of this channel are still lacking. By aligning distantly related calcium-activated ion channels in the TMEM16 family and conducting systematic mutagenesis of all conserved acidic residues thought to be exposed to the cytoplasm, we identify four acidic amino acids as putative calcium-binding residues. Alterations of the charge, polarity, and size of amino acid side chains at these sites alter the ability of different divalent cations to activate the channel. Furthermore, TMEM16A mutant channels containing double cysteine substitutions at these residues are sensitive to the redox potential of the internal solution, providing evidence for their physical proximity and solvent accessibility. DOI: http://dx.doi.org/10.7554/eLife.02772.001 PMID:24980701

  18. Crystallization of sodium chloride from a concentrated calcium chloride-potassium chloride-sodium chloride solution in a CMSMPR crystallizer: Observation of crystal size distribution and model validation

    NASA Astrophysics Data System (ADS)

    Choi, Byung Sang

    Compared to overwhelming technical data available in other advanced technologies, knowledge about particle technology, especially in particle synthesis from a solution, is still poor due to the lack of available equipment to study crystallization phenomena in a crystallizer. Recent technical advances in particle size measurement such as Coulter counter and laser light scattering have made in/ex situ study of some of particle synthesis, i.e., growth, attrition, and aggregation, possible with simple systems. Even with these advancements in measurement technology, to grasp fully the crystallization phenomena requires further theoretical and technical advances in understanding such particle synthesis mechanisms. Therefore, it is the motive of this work to establish the general processing parameters and to produce rigorous experimental data with reliable performance and characterization that rigorously account for the crystallization phenomena of nucleation, growth, aggregation, and breakage including their variations with time and space in a controlled continuous mixed-suspension mixed-product removal (CMSMPR) crystallizer. This dissertation reports the results and achievements in the following areas: (1) experimental programs to support the development and validation of the phenomenological models and generation of laboratory data for the purpose of testing, refining, and validating the crystallization process, (2) development of laboratory well-mixed crystallizer system and experimental protocols to generate crystal size distribution (CSD) data, (3) the effects of feed solution concentration, crystallization temperature, feed flow rate, and mixing speed, as well as different types of mixers resulting in the evolution of CSDs with time from a concentrated brine solution, (4) with statistically designed experiments the effects of processing variables on the resultant particle structure and CSD at steady state were quantified and related to each of those operating conditions by studying the detailed crystallization processes, such as nucleation, growth, and breakage, as well as agglomeration. The purification of CaCl2 solution involving the crystallization of NaCl from the solution mixture of CaCl2, KCl, and NaCl as shipped from Dow Chemical, Ludington, in a CMSMPR crystallizer was studied as our model system because of its nucleation and crystal growth tendencies with less agglomeration. This project also generated a significant body of experimental data that are available at URL that is http://www.che.utah.edu/˜ring/CrystallizationWeb.

  19. A Comparative Study of the Effectiveness of Calcium Propionate and Calcium Chloride for the Prevention of Parturient Paresis in Dairy Cows

    Microsoft Academic Search

    B. Pehrson; C. Svensson; M. Jonsson

    1998-01-01

    The efficacy of calcium propionate for the preven- tion of parturient paresis (milk fever) was compared with that of calcium chloride using 194 cows that had experienced milk fever during the previous calving. The cows were mainly of the Swedish Red and White and Swedish Friesian breeds and were divided ran- domly into an experimental group (n = 99) and

  20. Performance of calcium/thionyl chloride cells containing Sr(AlCl4)2 electrolyte

    NASA Astrophysics Data System (ADS)

    Wade, William L., Jr.; Walker, Charles W., Jr.; Binder, Michael

    1989-12-01

    Room temperature (RT) and -30 C discharges of hermetically sealed, D-sized calcium thionyl chloride cells, prepared with Sr(AlCl4)2 electrolyte containing 20 percent added SO2, were carried out on cells after storage for various lengths of time at room temperature and at 55 C. The performance of these cells was considerably poorer than that typically observed for Li/SO2 cells.

  1. Effect of calcium chloride on pH and availability of zinc and phosphorus in three calcareous soils 

    E-print Network

    Podisuk, Varangkana

    1976-01-01

    EFFECT OF CALCIUM CHLORIDE ON pH AND AVAILABILITY OF ZINC AND PHOSPHORUS IN THREE CALCAREOUS SOILS A Thesis by Varangkana Podisuk Submitted to the Graduate College of Texas AEM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May l976 Major Subject: Soil Chemistry EFFECT OF CALCIUM CHLORIDE ON pH AND AVAILABILITY OF ZINC AND PHOSPHORUS IN THREE CALCAREOUS SOILS A Thesis by Varangkana Podisuk Approved as to style and content by: (Chairman...

  2. Effect of calcium chloride on pH and availability of zinc and phosphorus in three calcareous soils

    E-print Network

    Podisuk, Varangkana

    1976-01-01

    EFFECT OF CALCIUM CHLORIDE ON pH AND AVAILABILITY OF ZINC AND PHOSPHORUS IN THREE CALCAREOUS SOILS A Thesis by Varangkana Podisuk Submitted to the Graduate College of Texas AEM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May l976 Major Subject: Soil Chemistry EFFECT OF CALCIUM CHLORIDE ON pH AND AVAILABILITY OF ZINC AND PHOSPHORUS IN THREE CALCAREOUS SOILS A Thesis by Varangkana Podisuk Approved as to style and content by: (Chairman...

  3. Experimental evidence for calcium-chloride ion pairs in the interlayer of montmorillonite. A XRD profile modeling approach

    E-print Network

    Boyer, Edmond

    Experimental evidence for calcium-chloride ion pairs in the interlayer of montmorillonite. A XRD layers which is best explained by the presence of cation ­ chloride ion pairs replacing the divalent be significantly altered as a consequence of storage-induced perturbations. For example, the use of concrete

  4. Aggregation patterns of bile salts: crystal structure of calcium cholate chloride heptahydrate.

    PubMed

    Hogan, A; Ealick, S E; Bugg, C E; Barnes, S

    1984-08-01

    Crystals of calcium cholate chloride heptahydrate, CaC24H39O7Cl . 7H2O, are monoclinic, space group P2(1), with a = 11.918(2), b = 8.636(1), c = 15.302(3) A, beta = 97.93(3) degrees, V = 1559.9(8) A3, and Z = 2. A trial structure was obtained by Patterson and Fourier techniques and was refined by full-matrix least-squares calculations using absorption corrected CuK-alpha diffractometer data. The final R index is 0.047. The crystal structure contains bilayer-type arrangements, with hydrophobic portions of cholate rings sandwiched between layers of polar groups that are interacting with calcium ions and water molecules. The calcium ion is coordinated to five water molecules and to the two carboxylate oxygen atoms of the cholate residue. Two additional water molecules are involved only in crystal packing through the formation of hydrogen bonds. Cholate-cholate hydrophobic interactions involve contacts between the hydrocarbon portions of the carboxylate sidechains and the A and B rings. This results in a staggered packing pattern that is nearly identical to that found in crystals of sodium cholate and rubidium deoxycholate. Similar bilayer aggregation patterns may also be involved in the formation of bile salt micelles in aqueous media. The characteristic bilayer packing arrangement can accommodate a variety of cation-binding patterns, as evidenced by the finding that calcium, sodium, and rubidium ions interact with the polar faces of the bilayers in different ways. The carboxylate sidechain displays two different conformations in the crystal structure of calcium cholate chloride heptahydrate. Variation in sidechain conformation may be of importance in the adjustment required to accommodate different cation coordination schemes. PMID:6491524

  5. Influence of calcium chloride and aprotinin in the in vivo biological performance of a composite combining biphasic calcium phosphate granules and fibrin sealant.

    PubMed

    Le Guehennec, Laurent; Goyenvalle, Eric; Aguado, Eric; Pilet, Paul; Spaethe, Reiner; Daculsi, Guy

    2007-08-01

    Highly bioactive biomaterials have been developed to replace bone grafts in orthopedic revision and maxillofacial surgery for bone augmentation. A mouldable, self-hardening material can be obtained by combining TricOs Biphasic Calcium Phosphate Granules and Tissucol Fibrin Sealant. Two components, calcium chloride and antifibrinolytic agents (aprotinin), are essential for the stability of the fibrin clot. The ingrowth of cells in composites combining sealants without calcium chloride or with a low concentration of aprotinin was evaluated in vivo in an experiment on rabbits. Bone colonization was compared using TricOs alone or with the composite made from TricOs and the standard fibrin sealant. Without the addition of calcium chloride, the calcium ions released by the ceramic component interacted with the components of the sealant too late to stabilize the clot. With a low concentration of aprotinin, the degradation of the clot occurred more quickly, leading to the absence of a scaffold on which the bone cells could colonize the composite. Our results indicate that a stable fibrin scaffold is crucial for bone colonization. The low calcium chloride and low aprotinin groups have shown lower bone growth. Further studies will be necessary to determine the minimal amount of antifibrinolytic agent (aprotinin) necessary to allow the same level of osteogenic activity as the TricOs-fibrin glue composite. PMID:17387594

  6. International Union of Basic and Clinical Pharmacology. LXXXV: Calcium-Activated Chloride Channels

    PubMed Central

    Huang, Fen; Wong, Xiuming

    2012-01-01

    Calcium-activated chloride channels (CaCCs) are widely expressed in various tissues and implicated in physiological processes such as sensory transduction, epithelial secretion, and smooth muscle contraction. Transmembrane proteins with unknown function 16 (TMEM16A) has recently been identified as a major component of CaCCs. Detailed molecular analysis of TMEM16A will be needed to understand its structure-function relationships. The role this channel plays in physiological systems remains to be established and is currently a subject of intense investigation. PMID:22090471

  7. Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride

    PubMed Central

    2011-01-01

    Background Calcium chloride solution is an established injectable sterilant in dogs and other mammals. With cat populations a continuing problem, we sought to explore its first use in cats. Six cats per group were injected with 5%, 10% or 20% calcium chloride dihydrate in saline solution with lignocaine hydrochloride, a local anaesthetic. Results At the 60th day post-injection, cat testes were collected and showed complete testicular necrosis and replacement by fibrous tissue; very low sperm counts; and reduction of serum testosterone by at least 70% in 20% dose. Androgenic enzyme activities and their expressions were also reduced in all the treated groups along with intra-testicular testosterone concentration was also low. Increased testicular lipid peroxidation, with reduced antioxidants and mitochondrial membrane potential, were evident following calcium chloride treatments. However, there were no apparent changes in serum concentrations of cortisol, fasting blood sugar level, blood urea nitrogen, packed cell volume, or total serum protein following calcium chloride injection, suggesting that this method of sterilization is not associated with any general stress response. Conclusion Calcium chloride solution demonstrates potential for androgenesis-eliminating nonsurgical sterilization of male cats in addition to its proven efficacy in dogs and other mammals. PMID:21774835

  8. Calmodulin-dependent activation and inactivation of anoctamin calcium-gated chloride channels

    PubMed Central

    Vocke, Kerstin; Dauner, Kristin; Hahn, Anne; Ulbrich, Anne; Broecker, Jana; Keller, Sandro; Frings, Stephan

    2013-01-01

    Calcium-dependent chloride channels serve critical functions in diverse biological systems. Driven by cellular calcium signals, the channels codetermine excitatory processes and promote solute transport. The anoctamin (ANO) family of membrane proteins encodes three calcium-activated chloride channels, named ANO 1 (also TMEM16A), ANO 2 (also TMEM16B), and ANO 6 (also TMEM16F). Here we examined how ANO 1 and ANO 2 interact with Ca2+/calmodulin using nonstationary current analysis during channel activation. We identified a putative calmodulin-binding domain in the N-terminal region of the channel proteins that is involved in channel activation. Binding studies with peptides indicated that this domain, a regulatory calmodulin-binding motif (RCBM), provides two distinct modes of interaction with Ca2+/calmodulin, one at submicromolar Ca2+ concentrations and one in the micromolar Ca2+ range. Functional, structural, and pharmacological data support the concept that calmodulin serves as a calcium sensor that is stably associated with the RCBM domain and regulates the activation of ANO 1 and ANO 2 channels. Moreover, the predominant splice variant of ANO 2 in the brain exhibits Ca2+/calmodulin-dependent inactivation, a loss of channel activity within 30 s. This property may curtail ANO 2 activity during persistent Ca2+ signals in neurons. Mutagenesis data indicated that the RCBM domain is also involved in ANO 2 inactivation, and that inactivation is suppressed in the retinal ANO 2 splice variant. These results advance the understanding of Ca2+ regulation in anoctamin Cl? channels and its significance for the physiological function that anoctamin channels subserve in neurons and other cell types. PMID:24081981

  9. Effects of Postmortem Injection Time, Injection Level, and Concentration of Calcium Chloride on Beef Quality Traits

    Microsoft Academic Search

    T. L. Wheeler; M. Koohmaraie; J. L. Lansdell; G. R. Siragusa; M. F. Miller

    Two experiments were conducted to determine the optimum protocol for maximizing meat quality with CaC12 injection. Experiment 1 compared the effects of 30 min or 24 h postmortem injection of 175 mM CaCl2 or water at 10% (wt\\/wt) to controls on various measures of meat quality. An injection of CaC12 reduced (P < .05) shear force values in all three

  10. Ellagic acid improved arrhythmias induced by CaCL2 in the rat stress model

    PubMed Central

    Dianat, Mahin; Amini, Negin; Badavi, Mohammad; Farbood, Yaghoub

    2015-01-01

    Objective: In ventricular arrhythmias, due to their free radical scavenging action, antioxidant agents are usually used in the treatment of cardiovascular disease. Since stress is considered as risk factor for increased mortality by causing malignant arrhythmias, the study was designed to evaluate the cardioprotective effects of ellagic acid (EA) on CaCl2-induced arrhythmias in rat stress model. Materials and Methods: Male Sprague-Dawley rats (200-250 g) were divided into four groups: Group I: Control rats (2 ml of saline by gavage), Group II: Rats treated with EA (15 mg/kg, gavage), Group III: stress group, Group IV: received EA plus stress. Stress was applied in a restrainer box (6 hour/day, 21 days). After induction of anesthesia, lead II electrocardiogram was recorded for calculating heart rate and QRS complex. The arrhythmia was produced by injection of CaCl2 solution (140 mg/kg, iv) and incidences of Ventricular fibrillation, Ventricular premature beats and Ventricular tachycardia were recorded. Results were analyzed by using one-way ANOVA and Fisher`s exact test. p<0.05 was considered as significant level. Results: The results showed a positive inotropic effect and negative chronotropic effect for the EA group in comparison with the control group. Incidence rates (%) of premature beats, ventricular fibrillation and ventricular tachycardia in stress group and all the arrhythmia parameters decreased in groups which received EA. Conclusions: By decreasing the incidence rates of premature beats, fibrillation and ventricular tachycardia in groups which received EA, ellagic acid probably acted as an anti-arrhythmic agent which showed to have aprotective functionin heart. PMID:25949953

  11. Near-Infrared Spectroscopic Investigation of Water in Supercritical CO2 and the Effect of CaCl2

    SciTech Connect

    Wang, Zheming; Felmy, Andrew R.; Thompson, Christopher J.; Loring, John S.; Joly, Alan G.; Rosso, Kevin M.; Schaef, Herbert T.; Dixon, David A.

    2013-01-25

    Near-infrared (NIR) spectroscopy was applied to investigate the dissolution and chemical interaction of water dissolved into supercritical carbon dioxide (scCO2) and the influence of CaCl2 in the co-existing aqueous phase at fo empe e : 40 50 75 nd 100 C at 90 atm. Consistent with the trend of the vapor pressure of water, the solubility of pure water in scCO2 inc e ed f om 40 ?C (0.32 mole%) o 100 ?C (1.61 mole%). The presence of CaCl2 negatively affects the solubility of water in scCO2: at a given temperature and pressure the solubility of water decreased as the concentration of CaCl2 in the aqueous phase increased, following the trend of the activity of water. A 40 ?C, the water concentration in scCO2 in contact with saturated CaCl2 aqueous solution was only 0.16 mole%, a drop of more than 50% as compared to pure water while that a 100 ?C was 1.12 mole%, a drop of over 30% as compared to pure water, under otherwise the same conditions. Analysis of the spectral profiles suggested that water dissolved into scCO2 exists in the monomeric form under the evaluated temperature and pressure conditions, for both neat water and CaCl2 solutions. However, its rotational degrees of freedom decrease at lower temperatures due to higher fluid densities, leading to formation of weak H2O:CO2 Lewis acid-base complexes. Similarly, the nearly invariant spectral profiles of dissolved water in the presence and absence of saturated CaCl2 under the same experimental conditions was taken as evidence that CaCl2 dissolution in scCO2 was limited as the dissolved Ca2+/CaCl2 would likely be highly hydrated and would alter the overall spectra of waters in the scCO2 phase.

  12. Anoctamins support calcium-dependent chloride secretion by facilitating calcium signaling in adult mouse intestine.

    PubMed

    Schreiber, Rainer; Faria, Diana; Skryabin, Boris V; Wanitchakool, Podchanart; Rock, Jason R; Kunzelmann, Karl

    2015-06-01

    Intestinal epithelial electrolyte secretion is activated by increase in intracellular cAMP or Ca(2+) and opening of apical Cl(-) channels. In infants and young animals, but not in adults, Ca(2+)-activated chloride channels may cause secretory diarrhea during rotavirus infection. While detailed knowledge exists concerning the contribution of cAMP-activated cystic fibrosis transmembrane conductance regulator (CFTR) channels, analysis of the role of Ca(2+)-dependent Cl(-) channels became possible through identification of the anoctamin (TMEM16) family of proteins. We demonstrate expression of several anoctamin paralogues in mouse small and large intestines. Using intestinal-specific mouse knockout models for anoctamin 1 (Ano1) and anoctamin 10 (Ano10) and a conventional knockout model for anoctamin 6 (Ano6), we demonstrate the role of anoctamins for Ca(2+)-dependent Cl(-) secretion induced by the muscarinic agonist carbachol (CCH). Ano1 is preferentially expressed in the ileum and large intestine, where it supports Ca(2+)-activated Cl(-) secretion. In contrast, Ano10 is essential for Ca(2+)-dependent Cl(-) secretion in jejunum, where expression of Ano1 was not detected. Although broadly expressed, Ano6 has no role in intestinal cholinergic Cl(-) secretion. Ano1 is located in a basolateral compartment/membrane rather than in the apical membrane, where it supports CCH-induced Ca(2+) increase, while the essential and possibly only apical Cl(-) channel is CFTR. These results define a new role of Ano1 for intestinal Ca(2+)-dependent Cl(-) secretion and demonstrate for the first time a contribution of Ano10 to intestinal transport. PMID:24974903

  13. The effect of postharvest calcium application in hydro-cooling water on tissue calcium content, biochemical changes, and quality attributes of sweet cherry fruit.

    PubMed

    Wang, Yan; Xie, Xingbin; Long, Lynn E

    2014-10-01

    To improve storage/shipping quality of sweet cherry (Prunus avium L.), the effect of calcium chloride (CaCl2) added to hydro-cooling water on physiological and biochemical processes related to fruit and pedicel quality was investigated on two major cultivars. The fruit tissue Ca content increased up to 29-85% logarithmically for 'Sweetheart' and 39-188% linearly for 'Lapins' as CaCl2 rate increased from 0.2% to 2.0% at 0 °C for 5 min. The increase of fruit tissue Ca content was accompanied by reductions in respiration rate, ascorbic acid degradation, and membrane lipid peroxidation, which enhanced total phenolics content and total antioxidant capacity, and resulted in increases in fruit firmness and pitting resistance and decreases in titratable acidity loss and decay of both cultivars. Pedicel browning was inhibited by CaCl2 at 0.2% and 0.5%, but increased by higher rates at 1.0% and 2.0%, possibly via modifying membrane lipid peroxidation. PMID:24799204

  14. GTP-binding proteins mediate noradrenaline effects on calcium and chloride currents in rat portal vein myocytes.

    PubMed Central

    Loirand, G; Pacaud, P; Mironneau, C; Mironneau, J

    1990-01-01

    1. Membrane currents were recorded by a patch-clamp pipette technique in cultured cells from rat portal vein using the whole-cell mode. 2. Noradrenaline (NA, 10(-5) M) and phorbol-12,13-dibutyrate (PDBu, 10(-7) M) produced an increase in voltage-dependent inward current carried by barium (5 mM), but their effects were not additive. Calcium-activated chloride current was evoked by NA but not by PDBu. 3. The NA-induced increase in peak voltage-dependent inward current was inhibited by intracellular application of GDP-beta-S (10(-3) M) while the effect of PDBu was unchanged. GDP-beta-S blocked the NA-induced chloride current but had no effect on the caffeine-induced chloride current. 4. Inclusion of GTP-gamma-S (10(-5)-10(-4) M) in the pipette solution increased the voltage-dependent inward current and inhibited the NA- or PDBu-induced increase in peak current. GTP-gamma-S potentiated the effect of NA on calcium-activated chloride current. At higher concentrations (10(-3) M), GTP-gamma-S activated the chloride current and prevented the effects of NA or caffeine on this current. 5. The combination of 10(-5) M-aluminium chloride and 10(-2) M-sodium fluoride had an effect similar to that of high concentrations of GTP-gamma-S on both inward current and calcium-activated chloride current. In contrast, arachidonic acid (10(-3) M) had no effect on calcium and chloride conductances activated by NA. 6. Cells responded normally to NA after pre-treatment for 4-30 h with 10 micrograms ml-1 pertussis toxin (PTx). 7. It is concluded that the stimulation of calcium and chloride conductances by NA is mediated through activation of a PTx-insensitive GTP-binding protein. This effect may involve activation of phospholipase C enzyme and production of both D-myo-inositol 1,4,5-trisphosphate which depletes calcium stores and diacylglycerol which activates protein kinase C. PMID:1700111

  15. Water deficit stress mitigation by calcium chloride in Catharanthus roseus: Effects on oxidative stress, proline metabolism and indole alkaloid accumulation

    Microsoft Academic Search

    C. Abdul Jaleel; P. Manivannan; B. Sankar; A. Kishorekumar; R. Gopi; R. Somasundaram; R. Panneerselvam

    2007-01-01

    The present investigation was conducted to determine whether CaCl2 increases Catharanthus roseus drought tolerance and if such tolerance is correlated with changes in oxidative stress, osmoregulation and indole alkaloid accumulation. C. roseus plants were grown under water deficit environments with or without CaCl2. Drought induced oxidative stress was measured in terms of lipid peroxidation (LPO) and H2O2 contents, osmolyte concentration,

  16. Crystalline transition and morphology variation of polyamide 6/CaCl2 composite during the decomplexation process

    NASA Astrophysics Data System (ADS)

    Liu, Shaoxuan; Zhang, Chengfeng; Proniewicz, Edyta; Proniewicz, Leonard M.; Kim, Younkyoo; Liu, Jun; Zhao, Ying; Xu, Yizhuang; Wu, Jinguang

    2013-11-01

    In this work, we developed a new method to prepare porous PA6 with different morphologic feature and crystalline forms via the decomplexation of PA6/CaCl2 composite. The structures and morphology of thus obtained materials were characterized by vibrational spectroscopy (FT-IR and Raman) and scanning electron microscope (SEM) method. When amorphous PA6/CaCl2 composite films were treated in water at room temperature, PA6 re-arranges into ? form. However, decomplexation of the PA6/CaCl2 composite in boiling water produces PA6 in ? crystalline form. If the PA6/CaCl2 composite is soaked in methanol, part of PA6 is dissolved or swollen in methanol/metal salt solutions. As a result, a dissolve/precipitation process occurred during the decomplexation process, which led to the formation of PA6 in ? crystalline form. Further investigation demonstrates that the morphologies of the porous PA6 could be adjusted by using different solvents and/or different decomplexation conditions.

  17. EPR and Magnetic Susceptibility Studies of Iron Ions in 3B2O3 . CaCl2 Glass Matrix

    NASA Astrophysics Data System (ADS)

    Ardelean, I.; Pascuta, P.

    Glass matrix 3B2O3 . CaCl2 doped with iron ions up to 50 mol% were obtained and investigated by means of EPR and magnetic susceptibility. Information concerning the structural units involving iron ions, valence states and the type of the interactions between these ions were discussed.

  18. PHYTOTOXICITY OF SALTS IN COMPOSTED SEWAGE SLUDGE AND CORRELATION WITH SODIUM CHLORIDE, CALCIUM NITRATE, AND MAGNESIUM NITRATE

    Microsoft Academic Search

    Hong Cai; Ding Gao

    2011-01-01

    The phytotoxicity of salts in composted sewage sludge (CSS) was evaluated. Concentrations of sodium (Na), chloride (Cl), calcium (Ca), and magnesium (Mg) were present at levels that would induce salt stress in plants. Nutrient imbalances were also found that would adversely affect the use of CSS as a growth medium. To further understand the phytotoxic nature of these salts, sodium

  19. Don Juan Pond, Antarctica: near-surface CaCl(2)-brine feeding Earth's most saline lake and implications for Mars.

    PubMed

    Dickson, James L; Head, James W; Levy, Joseph S; Marchant, David R

    2013-01-01

    The discovery on Mars of recurring slope lineae (RSL), thought to represent seasonal brines, has sparked interest in analogous environments on Earth. We report on new studies of Don Juan Pond (DJP), which exists at the upper limit of ephemeral water in the McMurdo Dry Valleys (MDV) of Antarctica, and is adjacent to several steep-sloped water tracks, the closest analog for RSL. The source of DJP has been interpreted to be deep groundwater. We present time-lapse data and meteorological measurements that confirm deliquescence within the DJP watershed and show that this, together with small amounts of meltwater, are capable of generating brines that control summertime water levels. Groundwater input was not observed. In addition to providing an analog for RSL formation, CaCl(2) brines and chloride deposits in basins may provide clues to the origin of ancient chloride deposits on Mars dating from the transition period from "warm/wet" to "cold/dry" climates. PMID:23378901

  20. Don Juan Pond, Antarctica: Near-surface CaCl2-brine feeding Earth's most saline lake and implications for Mars

    PubMed Central

    Dickson, James L.; Head, James W.; Levy, Joseph S.; Marchant, David R.

    2013-01-01

    The discovery on Mars of recurring slope lineae (RSL), thought to represent seasonal brines, has sparked interest in analogous environments on Earth. We report on new studies of Don Juan Pond (DJP), which exists at the upper limit of ephemeral water in the McMurdo Dry Valleys (MDV) of Antarctica, and is adjacent to several steep-sloped water tracks, the closest analog for RSL. The source of DJP has been interpreted to be deep groundwater. We present time-lapse data and meteorological measurements that confirm deliquescence within the DJP watershed and show that this, together with small amounts of meltwater, are capable of generating brines that control summertime water levels. Groundwater input was not observed. In addition to providing an analog for RSL formation, CaCl2 brines and chloride deposits in basins may provide clues to the origin of ancient chloride deposits on Mars dating from the transition period from “warm/wet” to “cold/dry” climates. PMID:23378901

  1. Depolarizing chloride gradient in developing cochlear nucleus neurons: underlying mechanism and implication for calcium signaling.

    PubMed

    Witte, M; Reinert, T; Dietz, B; Nerlich, J; Rübsamen, R; Milenkovic, I

    2014-03-01

    Precise regulation of the chloride homeostasis crucially determines the action of inhibitory transmitters GABA and glycine and thereby endows neurons or even discrete neuronal compartments with distinct physiological responses to the same transmitters. In mammals, the signaling mediated by GABAA/glycine receptors shifts during early postnatal life from depolarization to hyperpolarization, due to delayed maturation of the chloride homeostasis system. While the activity of the secondary active, K(+)-Cl(-)-extruding cotransporter KCC2, renders GABA/glycine hyperpolarizing in auditory brainstem nuclei of altricial rodents, the mechanisms contributing to the initially depolarizing transmembrane gradient for Cl(-) in respective neurons remained unknown. Here we used gramicidin-perforated patch recordings, non-invasive Cl(-) and Ca(2+) imaging, and immunohistochemistry to identify the Cl(-)-loading transporter that renders depolarizing effects of GABA/glycine in early postnatal life of spherical bushy cells in the cochlear nucleus of gerbil. Our data identify the 1Na(+):1K(+):2Cl(-) cotransporter 1 (NKCC1) as the major Cl(-)-loader responsible for depolarizing action of GABA/glycine at postnatal days 3-5 (P3-5). Extracellular GABA/muscimol elicited calcium signaling through R-, L-, and T-type channels, which was dependent on bumetanide- and [Na(+)]e-sensitive Cl(-) accumulation. The "adult like", low intracellular Cl(-) concentration is established during the second postnatal week, through a mechanism engaging the NKCC1-down regulation between P5 and P15 and ongoing KCC2-mediated Cl(-)-extrusion. PMID:24388924

  2. [Calcium-dependent chloride channels in plasma membrane of oocytes from toad, Bufo bufo gargarizans].

    PubMed

    Pi, Yan-Li; Ma, Ji-Hua; Zhang, Pei-Hua; Duan, Jing-Jing

    2006-10-25

    In this paper, membrane current properties of the fully-grown oocytes from toad, Bufo bufo gargarizans, were studied by using two-microelectrode voltage clamp technique. Axion of adult female toad was destroyed, and then ovarian lobes containing oocytes in stage I to VI were removed and incubated in Ca(2+)-free ND96 solution with collagenase (1.5 mg/ml) for 1 h. Subsequently, the oocytes were washed in Ca(2+)-free ND96 solution for 10 min to completely remove the follicular layer. For the experiments only the oocytes in stage V and VI were selected and used during 1 to 5 d. The membrane was depolarized from a holding potential of -80 mV to +60 mV in 10 mV step. It was found that a sustained outward current was elicited by depolarization. Potassium channel blockers (tetraethylammonium chloride, TEA, 10 mmol/L and 4-aminopyridine, 4-AP, 10 mmol/L) reduced the outward current to (23.4+/-0.72)% of the maximum. However, further addition of chloride channel blocker (5-nitro-2, 3-phenypropylamino benzoate, NPPB, 30 micromol/L) could almost completely block the outward current to (2.1+/-0.08)% of the maximum. In the presence of TEA and 4-AP, removal of extracellular Ca(2+) or adding verapamil (40 micromol/L), could also reduce the outward current to (2.2+/-0.04) % and (3.1+/-0.15) % of the maximum, respectively. It is concluded that calcium-dependent chloride channels exist in plasma membrane of Bufo bufo gargarizans oocytes, besides potassium channels. PMID:17041732

  3. Effect of oral calcium and calcium + fluoride treatments on mouse bone properties during suspension

    NASA Technical Reports Server (NTRS)

    Simske, S. J.; Luttges, M. W.; Allen, K. A.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    The bone effects of oral dosages of calcium chloride with or without supplementary sodium fluoride were assessed in antiorthostatically suspended mice. Two calcium dosages were used to replace half (3.1 mM) or all(6.3 mM) of the dietary calcium lost due to reduced food intake by the suspended mice. Two groups of 6.3 mM CaCl2-treated mice were additionally treated with 0.25 or 2.5 mM NaF. The results indicate that supplementation of the mouse drinking water with calcium salts prevents bone changes induced by short-term suspension, while calcium salts in combination with fluoride are less effective as fluoride dosage increases. However, the calcium supplements change the relationship between the femur mechanical properties and the mineral composition of the bone. Because of this, it appears that oral calcium supplements are effective through a mechanism other than simple dietary supplementation and may indicate a dependence of bone consistency on systemic and local fluid conditions.

  4. The effects of CaCl2 and CaBr2 on the reproduction of Daphnia magna Straus / U?inak CaCl2 i CaBr2 na razmnožavanje vodenbuhe (Daphnia magna Straus).

    PubMed

    Mažuran, Neda; Hršak, Vladimir; Kova?evi?, Goran

    2015-06-01

    Concentrated CaCl2 and CaBr2 salt solutions of densities up to 2.3 kg L-1 are regularly used to control hydrostatic pressure in oil wells during special operations in the exploration and production of natural gas and crude oil. Various concentrations of high density salts are frequently left in mud pits near the drilling site as waste, polluting fresh and ground waters by spillage and drainage. The toxic effects of these salts have already been observed. This study investigated the effects of CaCl2 and CaBr2 on water flea Daphnia magna Straus in a 21-day reproduction test. The three tested concentrations of CaCl2 (240, 481, and 1925 mg L-1) caused a significant dose-response decrease of reproduction (p<0.001). With CaBr2 (533 and 1066 mg L-1), only aborted eggs were produced, demonstrating the embryotoxicity of the substance. The results suggest that high concentrations of the tested chemicals are harmful to Daphnia's reproduction and could reduce its abundance. PMID:26110475

  5. Cobalt halide complex formation in aqueous calcium nitrate–ammonium nitrate melts. I. Cobalt(II) chlorides

    Microsoft Academic Search

    Milan Vraneš; Slobodan B. Gadžuri?; István J. Zsigrai

    2007-01-01

    Absorption spectra of cobalt(II) chloride in calcium nitrate–ammonium nitrate–water system of the composition xCa(NO3)2·4H2O–(1?x)NH4NO3 (x=0.30, 0.50 and 0.70) have been investigated in the wavelength range 400–800 nm at temperatures 45, 55 and 65 °C. Addition of chloride to cobalt nitrate solution caused a pronounced shift of the absorption maximum toward lower energies and a significant increase of absorption intensity, indicating a change

  6. Is functional manganese involved in hydrogen-peroxide-stimulated anomalous oxygen evolution in CACl 2 -washed photosystem II membranes?

    Microsoft Academic Search

    Steven P. Berg; Michael Seibert

    1987-01-01

    When detergent-derived photosystem II (PSII) membranes are treated with CaCl2 to remove the three extrinsic proteins associated with the O2-evolving complex, the resulting membranes (CaPSII) can still catalyze water oxidation if sufficient Ca2+ and Cl- are present. When CaPSII membranes are exposed to single turnover flashes on an O2 rate electrode, anomalous O2 is produced by the first two flashes.

  7. Small-molecule activators of TMEM16A, a calcium-activated chloride channel, stimulate epithelial chloride secretion and intestinal contraction

    PubMed Central

    Namkung, Wan; Yao, Zhen; Finkbeiner, Walter E.; Verkman, A. S.

    2011-01-01

    TMEM16A (ANO1) is a calcium-activated chloride channel (CaCC) expressed in secretory epithelia, smooth muscle, and other tissues. Cell-based functional screening of ?110,000 compounds revealed compounds that activated TMEM16A CaCC conductance without increasing cytoplasmic Ca2+. By patch-clamp, N-aroylaminothiazole “activators” (Eact) strongly increased Cl? current at 0 Ca2+, whereas tetrazolylbenzamide “potentiators” (Fact) were not active at 0 Ca2+ but reduced the EC50 for Ca2+-dependent TMEM16A activation. Of 682 analogs tested, the most potent activator (Eact) and potentiator (Fact) produced large and more sustained CaCC Cl? currents than general agonists of Ca2+ signaling, with EC50 3–6 ?M and Cl? conductance comparable to that induced transiently by Ca2+-elevating purinergic agonists. Analogs of activators were identified that fully inhibited TMEM16A Cl? conductance, providing further evidence for direct TMEM16A binding. The TMEM16A activators increased CaCC conductance in human salivary and airway submucosal gland epithelial cells, and IL-4 treated bronchial cells, and stimulated submucosal gland secretion in human bronchi and smooth muscle contraction in mouse intestine. Small-molecule, TMEM16A-targeted activators may be useful for drug therapy of cystic fibrosis, dry mouth, and gastrointestinal hypomotility disorders, and for pharmacological dissection of TMEM16A function.—Namkung, W., Yao, Z., Finkbeiner, W. E., Verkman, A. S. Small-molecule activators of TMEM16A, a calcium-activated chloride channel, stimulate epithelial chloride secretion and intestinal contraction. PMID:21836025

  8. Effects of pH, temperature, CaCl 2 and enzyme concentrations on the rennet-clotting properties of milk: a multifactorial study

    Microsoft Academic Search

    A. I. Nájera; M. de Renobales; L. J. R. Barron

    2003-01-01

    The effects of pH, coagulation temperature, CaCl2 and enzyme concentrations on the rennet clotting properties of milk were assessed. Rennet coagulation time, coagulum firmness, curd firmness and gel firming rate were the coagulation parameters measured using a gelograph. A multifactorial design, considering two levels of coagulation temperature (28 and 44 °C), pH (6.0 and 6.8) and concentration of CaCl2 (10 and

  9. Applicability of 0.01 M CaCl2 as a single extraction solution for the assessment of the nutrient status of soils and other diagnostic purposes

    Microsoft Academic Search

    V. J. G. Houba; I. Novozamsky; Th. M. Lexmond; J. J. van der Lee

    1990-01-01

    The applicability of 0.01 M CaCl2 solution as a single extraction agent for soils as a basis for fertilizer recommendation was tested on a variety of soils both from the Netherlands and from some tropical countries. Air?dry soil samples were subjected to extraction with 0.01 M CaCl2 and to several conventional extraction procedures, and the results were compared. In the

  10. Corrosion Effects of Calcium Chloride Injection for Mercury Control on the Pollution Control Equipment

    SciTech Connect

    Vijay Sethi; M.P. Sharma

    2009-02-28

    In response to the Clean Air Mercury Rule (CAMR) of 2005, Black Hills Power (BHP) initiated testing of a calcium chloride (CaCl{sub 2}) injection method in their Wygen 1 (Gillette, WY) coal-fired power plant to help lower mercury emissions. In 2006, Babcock & Wilcox (B&W) was contracted to test their CaCl{sub 2} technology in-situ by adding a CaCl{sub 2} solution onto the raw, pre-pulverized coal during normal operation of Wygen 1. Follow-up tests were conducted by BHP in 2007. Data were collected from these two time periods and analyzed by a collaborative investigation team from Western Research Institute (WRI) and the University of Wyoming (UW) to see if there were any effects on the current air pollution control systems. During a CaCl{sub 2} injection period in 2007, corrosion was monitored in the flue and recycle ash system by placing corrosion coupons in strategic locations to test if corrosion was enhanced by the CaCl{sub 2} injection. While the CaCl{sub 2} produced a reduction in stack mercury levels, there was some evidence of beneficial impacts on the removal of SO{sub 2} from the flue gas during CaCl{sub 2} injection. Data on NOx remained inconclusive. It was also discovered that corrosion was enhanced significantly in the Spray Drier Absorber (SDA) vessel and corresponding outlet ductwork during CaCl{sub 2} injections. Further studies are being carried out in the field and lab to better understand the corrosive effects of CaCl{sub 2} to help formulate operation controls to manage the increased corrosion rates.

  11. Possibility of inhibition of calcium-activated chloride channel rescuing erectile failures in diabetes.

    PubMed

    Lau, L-C; Adaikan, P G

    2014-01-01

    Although calcium-activated chloride channel (CaCC) blockers, niflumic acid (NFA) and anthracene-9-carboxylic acid (A9C), have been shown as potential erectogenic agents in healthy corpus cavernosum (CC) tissues, the pharmacological characteristics of CaCC blockers in diabetic state are relatively unknown. This study compares the direct muscle relaxant property of NFA and A9C with their influence on contraction and nitrergic relaxation as elicited by electrical field stimulation in normal and 16-week-old diabetic rabbit CC (n=8). Mean blood glucose level in alloxan-treated rabbits was elevated threefold (21.9±0.5?mmol ?l(-1) vs 7.1±0.2?mmol?l(-1) in untreated rabbits; P<0.05). There was no significant alteration in the efficacies of NFA and A9C in eliciting a concentration-dependent relaxation of noradrenaline-induced cavernosum tone and in inhibiting neurogenic contraction of CC from diabetic rabbits. The capability of NFA (100??M) and A9C (1?mM) in augmenting nitrergic transmission was also not adversely affected by diabetes. However, in CC from diabetic rabbits, A9C markedly increased nitrergic relaxation response to 1-10?Hz by 10.6-36.6% (vs -5.1-0.8% in nondiabetic control). CaCC sensitivity to A9C appears to be enhanced in diabetic CC tissue. Inhibiting the CaCC activity in diabetes-related ED may tip the balance between proerectile/relaxant and antierectile/contractile mechanisms in favor of cavernosum relaxation. PMID:24522228

  12. The involvement of lactic acid in calcium chloride injection of top and bottom rounds further processed into cooked corned beef and cooked beef 

    E-print Network

    McCleery, Carrie McReynolds

    1995-01-01

    ); .2M CaCl2 injection (CCL) and .2M CaCl2 injection with I% Lactic acid (LACCL). Top and bottom rounds were further processed into cooked beef and cooked corned beef, respectively. Cooked corned beef and cooked beef were randomly assigned to three...

  13. Calcium taste preferences: Genetic analysis and genome screen of C57BL/6J × PWK/PhJ hybrid mice

    PubMed Central

    Tordoff, Michael G.; Reed, Danielle R.; Shao, Hongguang

    2008-01-01

    To characterize the genetic basis of voluntary calcium consumption, we tested C57BL/6J mice (B6; with low avidity for calcium), PWK/PhJ mice (PWK; with high avidity for calcium) and their F1 and F2 hybrids. All mice received a series of 96-h two-bottle preference tests with a choice between water and the following: 50 mM CaCl2, 50 mM calcium lactate, 50 mM MgCl2, 100 mM KCl, 100 mM NH4Cl, 100 mM NaCl, 5 mM citric acid, 30 ?M quinine hydrochloride, and 2 mM saccharin. Most frequency distributions of the parental and F1 but not F2 groups were normally distributed, and there were few sex differences. Reciprocal cross analysis revealed that B6 × PWK F1 mice had a nonspecific elevation of fluid intake relative to PWK × B6 F1 mice. In the F2 mice, trait correlations were clustered among the divalent salts and the monovalent chlorides. A genome screen involving 116 short tandem repeat markers revealed 30 QTLs, of which six involved consumption of calcium chloride or lactate. The results demonstrate pleiotropic controls of calcium and magnesium consumption that are distinct from those controlling consumption of monovalent chlorides or exemplars of the primary taste qualities. PMID:18363849

  14. Long-Term Corrosion Behavior of Alloy 22 in 5M CaCl2 at 120 C

    SciTech Connect

    J.C. Estill; G.A. Hust; K.J. Evans; M.L. Stuart; R.B. Rebak

    2006-05-08

    In conditions where tight crevices exist in hot chloride containing solutions Alloy 22 may suffer crevice corrosion. The occurrence (or not) of crevice corrosion in a given environment (e.g, salt concentration and temperature), is governed by the values of the critical potential (E{sub crit}) for crevice corrosion and the corrosion potential (E{sub corr}). This paper discusses the evolution of E{sub corr} and corrosion rate (CR) of creviced Alloy 22 specimens in 5 M calcium chloride (CaCl{sub 2}) at 120 C. Tested specimens included non-creviced rods and multiple creviced assemblies (MCA) both non-welded (wrought) and welded. Results show that Alloy 22 suffers crevice corrosion under the open circuit conditions in the aerated hot CaCl{sub 2} brine. However, after more than a year of immersion the propagation of crevice corrosion was not significant. The general corrosion rate decreased or remained unchanged as the immersion time increased. For rods and MCA specimens, the corrosion rate was lower than 100 nm/year after more than a year immersion time.

  15. Effect of pre-harvest calcium chloride applications on fruit calcium level and post-harvest anthracnose disease of papaya

    E-print Network

    Biggs, Alan R.

    -harvest anthracnose disease of papaya Babak Madani a,*, Mahmud Tengku Muda Mohamed a,**, Alan R. Biggs c , Jugah Kadir October 2013 Keywords: Papaya Anthracnose Calcium Disease incidence Disease severity a b s t r a c t Anthracnose disease of papaya, caused by Colletotrichum gloeosporioides Penz, can cause extensive postharvest

  16. Calcium

    MedlinePLUS

    ... Consumer Datos en español Health Professional Other Resources Calcium Fact Sheet for Consumers What is calcium and what does it do? Calcium is a ... find out more about calcium? Disclaimer How much calcium do I need? The amount of calcium you ...

  17. In situ Raman spectra of the discharge products of calcium and lithium-anoded thionyl chloride cells — sulphur dioxide generation in oxyhalide systems

    NASA Astrophysics Data System (ADS)

    Hagan, W. P.; Sargeant, D. G.

    A cell has been constructed that allows a calcium or lithium-anoded oxyhalide cell of conventional composition to be analysed for catholyte-soluble discharge products using laser Raman spectroscopy. Both cells showed the presence of sulphur dioxide solvated by thionyl chloride. Species of the type M(SOCl 2)(SO 2) n+ (AlCl 4) n- could only be detected in cells having calcium or lithium anodes with LiAlCl 4 as the supporting electrolyte in thionyl chloride. Vapour pressure measurements of discharging cells confirmed that Ca(AlCl 4) 2 was less likely to form a complex with sulphur dioxide than the analogous lithium salt.

  18. The role of calcium in growth induced by indole-3-acetic acid and gravity in the leaf-sheath pulvinus of oat (Avena sativa)

    NASA Technical Reports Server (NTRS)

    Brock, T. G.; Burg, J.; Ghosheh, N. S.; Kaufman, P. B.

    1992-01-01

    Leaf-sheath pulvini of excised segments from oat (Avena sativa L.) were induced to grow by treatment with 10 micromoles indole-3-acetic acid (IAA), gravistimulation, or both, and the effects of calcium, EGTA, and calcium channel blockers on growth were evaluated. Unilaterally applied calcium (10 mM CaCl2) significantly inhibited IAA-induced growth in upright pulvini but had no effect on growth induced by either gravity or gravity plus IAA. Calcium alone had no effect on upright pulvini. The calcium chelator EGTA alone (10 mM) stimulated growth in upright pulvini. However, EGTA had no effect on either IAA- or gravity-induced growth but slightly diminished growth in IAA-treated gravistimulated pulvini. The calcium channel blockers lanthanum chloride (25 mM), verapamil (2.5 mM), and nifedipine (2.5 mM) greatly inhibited growth as induced by IAA (> or = 50% inhibition) or IAA plus gravity (20% inhibition) but had no effect on gravistimulated pulvini. Combinations of channel blockers were similar in effect on IAA action as individual blockers. Since neither calcium ions nor EGTA significantly affected the graviresponse of pulvini, we conclude that apoplastic calcium is unimportant in leaf-sheath pulvinus gravitropism. The observation that calcium ions and calcium channel blockers inhibit IAA-induced growth, but have no effect on gravistimulated pulvini, further supports previous observations that gravistimulation alters the responsiveness of pulvini to IAA.

  19. Parabrachial lesions in rats disrupt sodium appetite induced by furosemide but not by calcium deprivation.

    PubMed

    Grigson, P S; Colechio, E M; Power, M L; Schulkin, J; Norgren, R

    2015-03-01

    An appetite for CaCl2 and NaCl occurs in young rats after they are fed a diet lacking Ca or Na, respectively. Bilateral lesions of the parabrachial nuclei (PBN) disrupt normal taste aversion learning and essentially eliminate the expression of sodium appetite. Here we tested whether similar lesions of the PBN would disrupt the calcium-deprivation-induced appetite for CaCl2 or NaCl. Controls and rats with PBN lesions failed to exhibit a calcium-deprivation-induced appetite for CaCl2. Nevertheless, both groups did exhibit a significant calcium-deprivation-induced appetite for 0.5M NaCl. Thus, while damage to the second central gustatory relay in the PBN disrupts the appetite for 0.5M NaCl induced by furosemide, deoxycorticosterone acetate, and polyethylene glycol, the sodium appetite induced by dietary CaCl2 depletion remains intact. PMID:25540931

  20. Thermotolerance and antioxidant systems in Agrostis stolonifera: involvement of salicylic acid, abscisic acid, calcium, hydrogen peroxide, and ethylene.

    PubMed

    Larkindale, Jane; Huang, Bingru

    2004-04-01

    This study investigated whether pre-treating plants with specific putative signaling components and heat acclimation would induce tolerance of a cool-season grass, creeping bentgrass (Agrostis stolonifera var. palustris), to subsequent heat stress and whether thermotolerance induction of those pretreatments was associated with the regulation of antioxidant regenerating enzymes. The treatments included foliar application of salicylic acid (SA), abscisic acid (ABA), calcium chloride (CaCl2), hydrogen peroxide (H2O2), 1-aminocyclopropane-1-carboxylic acid (ACC, a precursor of ethylene prior to the exposure of plants to heat stress (35 degrees C) in a growth chamber. Physiological measurements including turf quality, leaf photosynthetic rate, and levels of oxidative damage demonstrated that all treatments increased heat tolerance. The better heat tolerance for pre-treated plants as compared to controls was related to the protection of oxidative damage under heat stress. APX activity increased over the first 2 days and 5 days of heating for ACC and CaCl2 respectively, but for only 12 h for H2O2. SA and ABA pre-treatments had no effects on APX activity earlier, but maintained APX activity at a significantly higher level than in controls after 24 h of heating. SA and ABA pre-treatments had no effects on POX activity. ACC treatment significantly increased POX activity. Pre-treatment with CaCl2, H2O2, and HA reduced POX activity, particularly during the later phase of heating. Plants treated with SA, CaCl2, H2O2 and HA had lower CAT activity than their control plants prior to heating and within 48 h of heat stress. ABA and ACC pre-treatments maintained higher CAT activity than the controls after 48 h of heating. ACC, CaCl2, or HA pre-treatments increased SOD activity only before 5 days of heat stress. SA and ABA pre-treatments had less effect on APX activity earlier under heat stress. These results suggest that specific groups of potential signaling molecules may induce tolerance of creeping bentgrass to heat stress by reducing oxidative damage. PMID:15128028

  1. Calcium

    MedlinePLUS

    ... of calcium dietary supplements are carbonate and citrate. Calcium carbonate is inexpensive, but is absorbed best when taken ... antacid products, such as Tums® and Rolaids®, contain calcium carbonate. Each pill or chew provides 200–400 mg ...

  2. The Transition from Proliferation to Differentiation in Colorectal Cancer Is Regulated by the Calcium Activated Chloride Channel A1

    PubMed Central

    Liu, Bin; McCaig, Colin D.; Pu, Jin

    2013-01-01

    Breaking the balance between proliferation and differentiation in animal cells can lead to cancer, but the mechanisms maintaining this balance remain largely undefined. The calcium activated chloride channel A1 (CLCA1) is a member of the calcium sensitive chloride conductance family of proteins and is expressed mainly in the colon, small intestine and appendix. We show that CLCA1 plays a functional role in differentiation and proliferation of Caco-2 cells and of intestinal tissue. Caco-2 cells spontaneously differentiate either in confluent culture or when treated with butyrate, a molecule present naturally in the diet. Here, we compared CLCA1 expressional levels between patients with and without colorectal cancer (CRC) and determined the functional role of CLCA1 in differentiation and proliferation of Caco-2 cells. We showed that: 1) CLCA1 and CLCA4 expression were down-regulated significantly in CRC patients; 2) CLCA1 expression was up-regulated in Caco-2 cells induced to differentiate by confluent culture or by treatment with sodium butyrate (NaBT); 3) Knockdown of CLCA1 with siRNA significantly inhibited cell differentiation and promoted cell proliferation in Caco-2 confluent cultures, and 4) In Caco-2 3D culture, suppression of CLCA1 significantly increased cell proliferation and compromised NaBT-induced inhibition of proliferation. In conclusion, CLCA1 may contribute to promoting spontaneous differentiation and reducing proliferation of Caco-2 cells and may be a target of NaBT-induced inhibition of proliferation and therefore a potential diagnostic marker for CRC prognosis. PMID:23593331

  3. Sex- and dose-dependent effects of post-trial calcium channel blockade by magnesium chloride on memory for inhibitory avoidance conditioning.

    PubMed

    Wilmott, Lynda A; Thompson, Lucien T

    2013-11-15

    Calcium influx through voltage-dependent Ca(2+) channels is critical for many neuronal processes required for learning and memory. Persistent increases in cytosolic intracellular Ca(2+) concentrations in aging neurons are associated with learning impairments, while small transient subcellular changes in intracellular calcium concentrations play critical roles in neural plasticity in young neurons. In the present study, young male and female Fisher 344 × Brown Norway (FBN) hybrid rats were administered different doses of magnesium chloride (0.0, 100.0, or 200.0mg/kg, i.p.) following a single inhibitory avoidance training trial. Extracellular magnesium ions can non-specifically block voltage-gated calcium channels, and/or reduce the calcium conductance gated via glutamate and serine's activation of neuronal NMDA receptors. In our study, magnesium chloride dose-dependently enhanced memory compared to controls (significantly increased latency to enter a dark compartment previously paired with an aversive stimulus) when tested 48 h later as compared to controls. A leftward shift in the dose response curve for memory enhancement by magnesium chloride was observed for male compared to female rats. These findings provide further insights into calcium-dependent modulation of aversive memory, and should be considered when assessing the design of effective treatment options for both male and female patients with dementia or other memory problems. PMID:24095881

  4. Influence of mass recovery on the performance of a heat pipe type ammonia sorption refrigeration system using CaCl 2\\/activated carbon as compound adsorbent

    Microsoft Academic Search

    T. X. Li; R. Z. Wang; L. W. Wang; Z. S. Lu; J. Y. Wu

    2008-01-01

    The performance analyses of a sorption refrigeration system with different mass recovery processes are presented, in which compound adsorbent of CaCl2 and activated carbon is used to improve the mass and heat transfer performances of sorption bed. The heating, cooling and heat recovery processes between two sorption beds were performed by multifunction heat pipes without additional power consumption. The experimental

  5. Functional expression of the TMEM16 family of calcium-activated chloride channels in airway smooth muscle

    PubMed Central

    Remy, Kenneth E.; Danielsson, Jennifer; Funayama, Hiromi; Fu, Xiao Wen; Chang, Herng-Yu Sucie; Yim, Peter; Xu, Dingbang; Emala, Charles W.

    2013-01-01

    Airway smooth muscle hyperresponsiveness is a key component in the pathophysiology of asthma. Although calcium-activated chloride channel (CaCC) flux has been described in many cell types, including human airway smooth muscle (HASM), the true molecular identity of the channels responsible for this chloride conductance remains controversial. Recently, a new family of proteins thought to represent the true CaCCs was identified as the TMEM16 family. This led us to question whether members of this family are functionally expressed in native and cultured HASM. We further questioned whether expression of these channels contributes to the contractile function of HASM. We identified the mRNA expression of eight members of the TMEM16 family in HASM cells and show immunohistochemical evidence of TMEM16A in both cultured and native HASM. Functionally, we demonstrate that the classic chloride channel inhibitor, 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), inhibited halide flux in cultured HASM cells. Moreover, HASM cells displayed classical electrophysiological properties of CaCCs during whole cell electrophysiological recordings, which were blocked by using an antibody selective for TMEM16A. Furthermore, two distinct TMEM16A antagonists (tannic acid and benzbromarone) impaired a substance P-induced contraction in isolated guinea pig tracheal rings. These findings demonstrate that multiple members of this recently described family of CaCCs are expressed in HASM cells, they display classic electrophysiological properties of CaCCs, and they modulate contractile tone in airway smooth muscle. The TMEM16 family may provide a novel therapeutic target for limiting airway constriction in asthma. PMID:23997176

  6. Pore size distribution of OPC & SRPC mortars in presence of chlorides

    Microsoft Academic Search

    A. K. Suryavanshi; J. D. Scantlebury; S. B. Lyon

    1995-01-01

    The pore structure of chloride-free ordinary portland cement(OPC) and sulphate resistant Portland cement(SRPC) mortars are compared with the corresponding mortars with NaCl and CaCl2 added during mixing. In both OPC and SRPC mortars the addition of chlorides reduced the total accessible pore volumes compared to the corresponding chloride-free mortars. Also, in the presence of chlorides, the number of coarse pores

  7. Calcium

    MedlinePLUS

    ... you eat. Foods rich in calcium include Dairy products such as milk, cheese, and yogurt Leafy, green vegetables Fish with soft bones that you eat, such as canned sardines and salmon Calcium-enriched foods such as breakfast ... tofu. Check the product labels. The exact amount of calcium you need ...

  8. EFFECTS OF pH AND OF VARIOUS CONCENTRATIONS OF SODIUM, POTASSIUM, AND CALCIUM CHLORIDE ON MUSCULAR ACTIVITY OF THE ISOLATED CROP OF PERIPLANETA AMERICANA (ORTHOPTERA)

    PubMed Central

    Griffiths, James T.; Tauber, Oscar E.

    1943-01-01

    1. Twenty-five solutions which contained KCl (0.0, 0.2, 0.4, 0.6, and 0.8 gm. per liter), in combination with CaCl2 (0.0, 0.2, 0.4, 0.6, and 0.8 gm. per liter), 10.0 gm. of NaCl, and 0.2 gm. of NaHCO3 per liter of solution were tested in order to determine satisfactory KCl/CaCl2 ratios in an insect physiological salt mixture for the maintenance of muscular activity by the isolated crop of the American roach. Satisfactory activity products (0.390 to 0.549) were obtained in seven mixtures with KCl/CaCl2 ratios of 0.2/0.2, 0.4/0.4, 0.6/0.6, 0.8/0.8, 0.2/0.4, 0.4/0.6, and 0.6/0.8, expressed as gram per liter. These ratios lie between 0.50 and 1.00. In solutions which contained calcium, but no potassium, approximately 50 per cent of the crops exhibited an initial tone increase and were arrested in rigor. See Fig. 2. In solutions which contained potassium, but no calcium, all crops showed an initial loss of tone and arrest in relaxation. See Fig. 2. 2. Seven KCl/CaCl2 ratios (see paragraph 1 above) were tested with eight NaCl concentrations (1.0, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, and 1.8 per cent) at a pH of 8.0. In these mixtures, the ones with KCl/CaCl2 ratios of less than 1.0 produced higher activity products than those with ratios equal to 1.00. The highest average activity product (0.849) was obtained in the solutions with 0.2 gm. of KCl and 0.4 gm. of CaCl2 per liter. 3. Four KCl/CaCl2 ratios (0.2/0.2, 0.4/0.4, 0.2/0.4, and 0.4/0.6 gm. per liter) were tested with 1.4, 1.5, and 1.6 per cent NaCl at a pH of 7.5. When analyzed with data from comparable solutions at a pH of 8.0, it was found that 1.4 per cent NaCl afforded an optimum environment for isolated crop activity. 4. Effects of hydrogen and hydroxyl ion concentrations were studied at pH values of 6.8, 7.5, 8.0, and 8.9. The highest average activity product, 1.011, was produced at a pH of about 8.0. 5. A satisfactory physiological salt solution for the isolated foregut of the American roach, Periplaneta americana, would contain 14.0 gm. of NaCl, 0.4 gm. of CaCl2, 0.2 gm. of KCl, and 0.2 gm. of NaHCO3 per liter of solution. This mixture should have a pH value between 7.8 and 8.2. 6. Durations of crop activity extending over periods as long as 25 hours were quite common, and several crops maintained contractions for more than 30 hours. The greatest longevity was for crop 814, from a female, which continued activity for slightly more than 47 hours. 7. A significant difference between the activity products of the crops from males and the crops from females was recorded. Although there was not a significant difference in the amount of food ingested by males and females, 12 hours after feeding there was more food in the females' crops, and the food progressed more rapidly through the males' crops than through the females'. In addition, crops from the two sexes reacted differently to the effects of day old solutions. This sex difference is apparently related to an inherently increased activity of the crop from the male roach. PMID:19873366

  9. Selective water sorbents for multiple applications, 3. CaCl 2 solution confined in micro- and mesoporous silica gels: Pore size effect on the “solidification-melting” diagram

    Microsoft Academic Search

    Yu. I. Aristov; G. Di Marco; M. M. Tokarev; V. N. Parmon

    1997-01-01

    In this communication we present a low-temperature “solidification-melting” phase diagram for CaCl2\\/H2O solutions confined in KSK and KSM silica gels. At salt concentrations of 0–48 wt. %, the diagram has been found to lie below\\u000a the diagram reported for the bulk system by 15–30C. It shows a depression of the solution melting point due to its confinment\\u000a to the pores.

  10. EFFECTS OF DIFFERENT CALCIUM FORMS ON GAS EXCHANGE ACTIVITIES, WATER USAGE AND MACRONUTRIENT UPTAKE BY STRAWBERRY PLANTS UNDER SODIUM CHLORIDE STRESS

    Microsoft Academic Search

    M. Khayyat; S. Khanizadeh; E. Tafazoli; S. Rajaee; B. Kholdebarin; Y. Emam

    2011-01-01

    Strawberry cv. ‘Selva’ was grown in soilless culture under greenhouse conditions to study the effects of supplementary calcium added to nutrient solution and applied to the plants grown under sodium chloride (NaCl) (35 mM) salinity. Treatments were: 1) commercial nutrient solution or control [expressed as (N)]; 2) N+NaCl (35 mM) [expressed as (NS)]; 3) NS+CaCl2 (5 mM) [expressed as (NS1)];

  11. Relationship between intracellular calcium and its muffling measured by calcium iontophoresis in snail neurones.

    PubMed Central

    Schwiening, C J; Thomas, R C

    1996-01-01

    1. We have measured intracellular free calcium ion concentration ([Ca2+]i) with fura-2, and intracellular chloride with chloride-sensitive microelectrodes, in voltage-clamped snail neurones. By making iontophoretic injections of CaCl2 we have investigated calcium muffling, the sum of the processes which minimize the calcium transient, at different values of [Ca2+]i. 2. By injection of calcium into cell-sized droplets of buffer we measured the calcium transport index. It was stable over the range pCa 6-7.4 (0.48 +/- 0.06 measured at pCa 6.70 +/- 0.12, n = 5). 3. Measurement of intracellular chloride activity during a series of fura-2-KCl pressure injections revealed a nearly linear relationship between fura-2 Ca(2+)-insensitive fluorescence and the sum of the increments in intracellular chloride. This allowed us to calculate the intracellular fura-2 concentration ([fura-2]i). 4. The rate of recovery of [Ca2+]i following a depolarization-induced load was increased by low [fura-2]i (10-20 microM) but decreased by higher [fura-2]i (40-80 microM). These effects are consistent with the addition of a mobile buffer to the cytoplasm. 5. Iontophoresis of Ca2+ at various membrane potentials allowed us to calculate the intracellular calcium muffling power (the amount of calcium required to cause a transient tenfold increase in [Ca2+]i per unit volume) and calcium muffling ratio (number of Ca2+ ions injected divided by the maximum increase in [Ca2+]i per unit volume) at different values of [Ca2+]i. 6. Calcium muffling power at resting [Ca2+]i was approximately 40 microM Ca2+ (pCa unit)-1, (about 250 times less than for hydrogen ions). It increased linearly about fivefold with [Ca2+]i over the range 20-120 nM (10 cells, 153 measurements) and therefore exponentially with decreasing pCa. 7. The calcium muffling ratio appeared to be constant (361 +/- 14, n = 10 cells, 130 measurements) over the range 20-120 nM Ca2+. 8. In three experiments we modelled the additional calcium buffering power produced by multiple pressure injections of fura-2 into voltage-clamped snail neurones. Back-extrapolation of the increases in calcium buffering power allowed us to calculate the calcium muffling power of the neurones. 9. Small increases in [fura-2]i (approximately 10 microM) significantly increased intracellular calcium muffling power in individual experiments. However, the variability among neurones in intracellular calcium muffling power was large enough to obscure the additional buffering produced by fura-2 in pooled experiments. PMID:8815198

  12. Light and Calcium Interactions in Chlorella Inhibited by Sodium Chloride 12

    PubMed Central

    Chimiklis, Phrosene E.; Karlander, Edward P.

    1973-01-01

    Analysis of NaCl toxicity in Chlorella sorokiniana showed decreased growth rates, increased dry weight per cell, increased intracellular Na+ and Cl?, more total chlorophyll per cell, a decreased chlorophyll a to chlorophyll b ratio, increased rates of O2 evolution, and decreased rates of CO2 fixation when the extracellular concentration of NaCl was increased from zero to 0.3 m. Cultures did not grow at concentrations greater than 0.3 m NaCl unless 10 mm calcium salts were present. Inclusion of that concentration of Ca2+ extended the tolerance to 0.5 m NaCl before growth stopped. Increasing the light intensity from 1.2 to 9.4 mw/cm2 increased growth rates for cultures in 0.10 to 0.45 m NaCl. At 14 mw/cm2 added Ca2+ reduced growth rates of cultures in 0.3 m NaCl compared to controls without added Ca2+. Maximal growth rates for cultures in NaCl media were achieved by addition of 10 mm CaSO4 and maintenance of the light intensity at 9.4 mw/cm2. The maximal growth rate of the organism was 9.6 doublings/day achieved at 2.7 mw/cm2 for control cultures. In 0.3 m NaCl the growth rate was 4.3 doublings/day at 2.7 mw/cm2 and 8.2 doublings/day at 9.4 mw/cm2 with 10 mm CaSO4 added. Increasing light intensities from 2.7 to 9.4 to 14 mw/cm2 decreased intracellular Na+ in cells cultured in 0.3 m NaCl medium without added Ca2+ and increased Cl? uptake in cells cultured in 0.3 m NaCl medium with and without added Ca2+. For cells cultured in 0.3 m NaCl medium at 14 mw/cm2 intracellular Na+ was 0.68 meq/g dry weight with Ca2+ added and 0.81 meq/g dry weight without Ca2+ added. Addition of Ca2+ at 2.7 mw/cm2 reduced intracellular Na+ to similar values. It is postulated that energy requirements for active Na+ exclusion were reduced by addition of Ca2+ allowing more energy to be used for cell growth resulting in increased growth rates. O2 evolution and CO2 fixation studies indicated that increased photosynthetic energy, probably actuated by a high proton gradient accompanying Cl? influx and uncoupled from CO2 fixation, was available for maintenance of cellular integrity and active control of intracellular ionic ratios. The O2 evolving capacity was destroyed at 12 and 29 mw/cm2 for cells cultured in 0.3 m NaCl medium respectively with and without the addition of Ca2+. Control cultures continued producing O2 at light intensities up to 115 mw/cm2. PMID:16658295

  13. Hypoxia augments the calcium-activated chloride current carried by anoctamin-1 in cardiac vascular endothelial cells of neonatal mice

    PubMed Central

    Wu, Ming-Ming; Lou, Jie; Song, Bin-Lin; Gong, Yuan-Feng; Li, Yan-Chao; Yu, Chang-Jiang; Wang, Qiu-Shi; Ma, Tian-Xing; Ma, Ke; Hartzell, H Criss; Duan, Dayue Darrel; Zhao, Dan; Zhang, Zhi-Ren

    2014-01-01

    BACKGROUND AND PURPOSE The molecular identity of calcium-activated chloride channels (CaCCs) in vascular endothelial cells remains unknown. This study sought to identify whether anoctamin-1 (Ano1, also known as TMEM16A) functions as a CaCC and whether hypoxia alters the biophysical properties of Ano1 in mouse cardiac vascular endothelial cells (CVECs). EXPERIMENTAL APPROACH Western blot, quantitative real-time PCR, confocal imaging analysis and patch-clamp analysis combined with pharmacological approaches were used to determine whether Ano1 was expressed and functioned as CaCC in CVECs. KEY RESULTS Ano1 was expressed in CVECs. The biophysical properties of the current generated in the CVECs, including the Ca2+ and voltage dependence, outward rectification, anion selectivity and the pharmacological profile, are similar to those described for CaCCs. The density of ICl(Ca) detected in CVECs was significantly inhibited by T16Ainh-A01, an Ano1 inhibitor, and a pore-targeting, specific anti-Ano1 antibody, and was markedly decreased in Ano1 gene knockdown CVECs. The density of ICl(Ca) was significantly potentiated in CVECs exposed to hypoxia, and this hypoxia-induced increase in the density of ICl(Ca) was inhibited by T16Ainh-A01 or anti-Ano1 antibody. Hypoxia also increased the current density of ICl(Ca) in Ano1 gene knockdown CVECs. CONCLUSIONS AND IMPLICATIONS Ano1 formed CaCC in CVECs of neonatal mice. Hypoxia enhances Ano1-mediated ICl(Ca) density via increasing its expression, altering the ratio of its splicing variants, sensitivity to membrane voltage and to Ca2+. Ano1 may play a role in the pathophysiological processes during ischaemia in heart, and therefore, Ano1 might be a potential therapeutic target to prevent ischaemic damage. PMID:24758567

  14. Calcium

    MedlinePLUS

    ... prevent falls in women, but not in men. Metabolic syndrome. Some evidence suggests that getting more calcium from ... vitamin D, might lower the risk of developing metabolic syndrome. Cancer. Research shows that healthy older women who ...

  15. TMEM16A Inhibitors Reveal TMEM16A as a Minor Component of Calcium-activated Chloride Channel Conductance in Airway and Intestinal Epithelial Cells*

    PubMed Central

    Namkung, Wan; Phuan, Puay-Wah; Verkman, A. S.

    2011-01-01

    TMEM16A (ANO1) functions as a calcium-activated chloride channel (CaCC). We developed pharmacological tools to investigate the contribution of TMEM16A to CaCC conductance in human airway and intestinal epithelial cells. A screen of ?110,000 compounds revealed four novel chemical classes of small molecule TMEM16A inhibitors that fully blocked TMEM16A chloride current with an IC50 < 10 ?m, without interfering with calcium signaling. Following structure-activity analysis, the most potent inhibitor, an aminophenylthiazole (T16Ainh-A01), had an IC50 of ?1 ?m. Two distinct types of inhibitors were identified. Some compounds, such as tannic acid and the arylaminothiophene CaCCinh-A01, fully inhibited CaCC current in human bronchial and intestinal cells. Other compounds, including T16Ainh-A01 and digallic acid, inhibited total CaCC current in these cells poorly, but blocked mainly an initial, agonist-stimulated transient chloride current. TMEM16A RNAi knockdown also inhibited mainly the transient chloride current. In contrast to the airway and intestinal cells, all TMEM16A inhibitors fully blocked CaCC current in salivary gland cells. We conclude that TMEM16A carries nearly all CaCC current in salivary gland epithelium, but is a minor contributor to total CaCC current in airway and intestinal epithelia. The small molecule inhibitors identified here permit pharmacological dissection of TMEM16A/CaCC function and are potential development candidates for drug therapy of hypertension, pain, diarrhea, and excessive mucus production. PMID:21084298

  16. Effects of chloride, calcium, and dissolved organic carbon on silver toxicity: Comparison between rainbow tout and fathead minnows

    SciTech Connect

    Bury, N.R. [INRA, Rennes (France). Lab. de Physiologie des Poissons; Galvez, F.; Wood, C.M. [McMaster Univ., Hamilton, Ontario (Canada). Dept. of Biology

    1999-01-01

    The effects of independently altering chloride, calcium, and dissolved organic carbon (DOC) on the toxicity of silver were compared between rainbow trout (Oncorhynchus mykiss) and fathead minnows (Pimephales promelas). The 96-h median lethal concentration toxicity tests for both species were performed under the same conditions, within the same containers. In addition, the effect of altering [Cl{sup {minus}}] on silver-induced perturbations to body Na{sup +} influx and gill silver load was studied. Toxicity tests were conducted in synthetic soft water (50 {micro}M Na{sup +}, 50 {micro}M Cl{sup {minus}}, 50 {micro}M Ca{sup 2+}, 0.3 mg DOC/L). The [Cl{sup {minus}}], [Ca{sup 2+}], and [DOC] were adjusted by the addition of NaCl, CaNO{sub 3}, or humic acid, respectively. On the basis of total silver, increasing [Cl{sup {minus}}] over a range of 50 {micro}M to 1,500 {micro}M resulted in a 4.3-fold increase in the 96-h LC50 values (decrease in toxicity) for rainbow trout, but did not significantly affect the 96-h LC50 values for fathead minnows. Increasing water [Ca{sup 2+}] (from 50 to 2,000 {micro}M) had only a small influence on the 96-h LC50 values in both species. If the 96-h LC50 values are calculated on the basis of ionic silver, Ag{sup +}, then, in the case of rainbow trout, toxicity correlates to Ag{sup +}. However, this correlation does not exist for fathead minnows. Increasing [Cl{sup {minus}}] did not affect the degree of perturbation of Na{sup +} influx during acute exposure (first 4 h) to 8 {micro}g Ag/L in either species, nor did it affect the whole-body silver uptake rates, but it did reduce the gill silver load. These results demonstrate that differences exist in the way in which water chemistry ameliorates silver toxicity between rainbow trout and fathead minnows.

  17. On the preparation of TiAl alloy by direct reduction of the oxide mixtures in calcium chloride melt

    SciTech Connect

    Prabhat K. Tripathy; Derek J. Fray

    2011-11-01

    In recent years, TiAl-based intermetallic alloys are being increasingly considered for application in areas such as (i) automobile/transport sector (passenger cars, trucks and ships) (ii) aerospace industry (jet engines and High Speed Civil Transport propulsion system) and (iii) industrial gas turbines. These materials offer excellent (i) high temperature properties (at higher than 6000C) (ii) mechanical strength and (iii) resistance to corrosion and as a result have raised renewed interest. The combination of these properties make them possible replacement materials for traditional nickel-based super-alloys, which are nearly as twice as dense (than TiAl based alloys). Since the microstructures of these intermetallic alloys affect, to a significant extent, their ultimate performance, further improvements (by way of alteration/modification of these microstructures), have been the subject matter of intense research investigations. It has now been established that the presence of alloy additives, such as niobium, tantalum, manganese, boron, chromium, silicon, nickel and yttrium etc, in specific quantities, impart marked improvement to the properties, viz. fatigue strength, fracture toughness, oxidation resistance and room temperature ductility, of these alloys. From a number of possible alloy compositions, {gamma}-TiAl and Ti-Al-Nb-Cr have, of late, emerged as two promising engineering alloys/materials. . The conventional fabrication process of these alloys include steps such as melting, forging and heat treatment/annealing of the alloy compositions. However, an electrochemical process offers an attractive proposition to prepare these alloys, directly from the mixture of the respective oxides, in just one step. The experimental approach, in this new process, was, therefore, to try to electrochemically reduce the (mixed) oxide pellet to an alloy phase. The removal of oxygen, from the (mixed) oxide pellet, was effected by polarizing the oxide pellet against a graphite electrode in a pool of molten calcium chloride at a temperature of 9000C. The dominant mechanism of the oxygen removal was the ionization of oxygen followed by its subsequent discharge, as CO2/CO, at the anode surface. The removal of oxygen from the oxide mixture helped form the alloy in situ. The presentation shall cover the detailed experimental results pertaining to the preparation, evaluation and characterization of Ti-47Al-2Nb-2Cr (atom%) alloy.

  18. Ion-pairing in aqueous CaCl2 and RbBr solutions: Simultaneous structural refinement of XAFS and XRD data

    NASA Astrophysics Data System (ADS)

    Pham, Van-Thai; Fulton, John L.

    2013-01-01

    We present a new methodology involving the simultaneous refinement of both x-ray absorption and x-ray diffraction spectra (x-ray absorption/diffraction structural refinement, XADSR) to study the hydration and ion pair structure of CaCl2 and RbBr salts in concentrated aqueous solutions. The XADSR method combines the x-ray absorption fine structure (XAFS) spectral analysis of both the cation and anion as a probe of their short-range structure with an x-ray diffraction (XRD) spectral analysis as a probe of the global structural. Together they deliver a comprehensive picture of the cation and anion hydration, the contact ion pair (CIP) structure, and the solvent-separated ion pair (SSIP) structure. XADSR analysis of 6.0 m aqueous CaCl2 reveals that there are ˜0.26 Ca2+-Cl- CIP's separated by about 2.71 Å, while there are 3.4 SSIP's separated by about 4.98 Å. In contrast XADSR analysis of 6 m aqueous RbBr yields about 0.7 pair CIP at a bond length of 3.51 Å. The present work demonstrates a new approach for a direct co-refinement of XRD and XAFS spectra in a simple and reliable fashion, opening new opportunities for analysis in various disordered and crystalline systems.

  19. Multisite ion model in concentrated solutions of divalent cations (MgCl2 and CaCl2): osmotic pressure calculations.

    PubMed

    Saxena, Akansha; García, Angel E

    2015-01-01

    Accurate force field parameters for ions are essential for meaningful simulation studies of proteins and nucleic acids. Currently accepted models of ions, especially for divalent ions, do not necessarily reproduce the right physiological behavior of Ca(2+) and Mg(2+) ions. Saxena and Sept (J. Chem. Theor. Comput. 2013, 9, 3538-3542) described a model, called the multisite-ion model, where instead of treating the ions as an isolated sphere, the charge was split into multiple sites with partial charge. This model provided accurate inner shell coordination of the ion with biomolecules and predicted better free energies for proteins and nucleic acids. Here, we expand and refine the multisite model to describe the behavior of divalent ions in concentrated MgCl2 and CaCl2 electrolyte solutions, eliminating the unusual ion-ion pairing and clustering of ions which occurred in the original model. We calibrate and improve the parameters of the multisite model by matching the osmotic pressure of concentrated solutions of MgCl2 to the experimental values and then use these parameters to test the behavior of CaCl2 solutions. We find that the concentrated solutions of both divalent ions exhibit the experimentally observed behavior with correct osmotic pressure, the presence of solvent separated ion pairs instead of direct ion pairs, and no aggregation of ions. The improved multisite model for (Mg(2+) and Ca(2+)) can be used in classical simulations of biomolecules at physiologically relevant salt concentrations. PMID:25482831

  20. Experimental determination of anorthite solubility and calcium speciation in supercritical chloride solutions at 2 kb from 400 to 600°C

    Microsoft Academic Search

    Gregory T. Roselle; Lukas P. Baumgartner

    1995-01-01

    The solubility of the assemblage anorthite + andalusite + quartz and Ca speciation were investigated in supercritical chloride solutions between 400 and 600°C at 2 kb over a total chloride range of 0.005–5.6 m. Species interpretation is based on systematic regression of multiple speciation schemes by a nonlinear, weighted least squares procedure. Best fits to the data were obtained by

  1. Niflumic acid inhibits chloride conductance of rat skeletal muscle by directly inhibiting the CLC-1 channel and by increasing intracellular calcium

    PubMed Central

    Liantonio, A; Giannuzzi, V; Picollo, A; Babini, E; Pusch, M; Conte Camerino, D

    2006-01-01

    Background and purpose: Given the crucial role of the skeletal muscle chloride conductance (gCl), supported by the voltage-gated chloride channel CLC-1, in controlling muscle excitability, the availability of ligands modulating CLC-1 are of potential medical as well as toxicological importance. Here, we focused our attention on niflumic acid (NFA), a molecule belonging to the fenamates group of non-steroidal anti-inflammatory drugs (NSAID). Experimental approach: Rat muscle Cl? conductance (gCl) and heterologously expressed CLC-1 currents were evaluated by means of current-clamp (using two-microelectrodes) and patch-clamp techniques, respectively. Fura-2 fluorescence was used to determine intracellular calcium concentration, [Ca2+]i, in native muscle fibres. Key results: NFA inhibited native gCl with an IC50 of 42 ?M and blocked CLC-1 by interacting with an intracellular binding site. Additionally, NFA increased basal [Ca2+]i in myofibres by promoting a mitochondrial calcium efflux that was not dependent on cyclooxygenase or CLC-1. A structure-activity study revealed that the molecular conditions that mediate the two effects are different. Pretreatment with the Ca-dependent protein kinase C (PKC) inhibitor chelerythrine partially inhibited the NFA effect. Therefore, in addition to direct channel block, NFA also inhibits gCl indirectly by promoting PKC activation. Conclusions and Implications: These cellular effects of NFA on skeletal muscle demonstrate that it is possible to modify CLC-1 and consequently gCl directly by interacting with channel proteins and indirectly by interfering with the calcium-dependent regulation of the channel. The effect of NFA on mitochondrial calcium stores suggests that NSAIDs, widely used drugs, could have potentially dangerous side-effects. PMID:17128287

  2. Alleviatory effects of calcium on the toxicity of sodium, potassium and magnesium chlorides to seed germination in three non-halophytes

    Microsoft Academic Search

    Kazuo Tobe; Liping Zhang; Kenji Omasa

    2003-01-01

    Saline soils contain numerous salts with varying impact on seed germination. Seeds of three non-halophytic species found in Chinese sandy deserts (Artemisia ordosica, Aristida adscensionis and Bassia dasyphylla) were incubated in salt solutions (NaCl, KCl or MgCl2, each with or without CaCl2) at 20°C in the dark. The effects of each salt on the percentage of seeds from which visibly

  3. Calcium-mediated responses and glutamine synthetase expression in greater duckweed (Spirodela polyrhiza L.) under diethyl phthalate-induced stress.

    PubMed

    Cheng, Lee-Ju; Hung, Meng-Ju; Cheng, Yen-I; Cheng, Tai-Sheng

    2013-11-15

    This study was carried out to assess the influence of diethyl phthalate (DEP) alone or associated with calcium chloride (CaCl2) on greater duckweed plants, emphasizing the implications of calcium in amelioration of DEP-induced stress on plant growth. Greater duckweed were treated with DEP in variable concentrations, as 0, 0.25, 0.5, 1.0 and 2.0mM for 7 days, or treated with the same concentration either 2mM DEP or 2mM DEP plus 10mM CaCl2·2H2O in different duration 0-7 days. Treatment with 2mM DEP resulted in increasing proline content, protease activity, and ammonia accumulation in duckweed tissues. NADH-glutamate dehydrogenase (NADH-GDH; EC 1.4.1.2) and ?(1)-pyrroline-5-carboxylate reductase (P5CR; EC 1.5.1.2), two key enzymes in the glutamate pathway of proline synthesis, showed increase in activity with DEP treatment and positively correlated with proline accumulation. No further increase in proline accumulation was observed with addition of calcium chloride to the DEP-treated cultures. However, supplementation of Ca(2+) can mitigate the adverse effect of DEP, at least in part to decrease the DEP-induced superoxide accumulation and increase in GDH activity for ammonia assimilation in duckweed fronds. In addition, effects of calcium on mitigation of DEP injury were also observed in glutamine synthetase (GS; EC 6.3.1.2) expression. Both GS1 and GS2 polypeptide accumulation and the level of total GS activity were nearly equivalent to the control. Exogenous proline protects GS2 from DEP-modulated redox damage in the chloroplast lysates but there is no remarkable protection effects on D1 (the 32kDa protein in photosystem II reaction center) degradation. In conclusion, the glutamate pathway of proline synthesis might be involved in mitigation of DEP-induced injury, and calcium plays an important role in increasing GDH, P5CR, and GS expression. PMID:24177215

  4. Change in organic molecule adhesion on ?-alumina (sapphire) with change in NaCl and CaCl2 solution salinity.

    PubMed

    Juhl, K M S; Bovet, N; Hassenkam, T; Dideriksen, K; Pedersen, C S; Jensen, C M; Okhrimenko, D V; Stipp, S L S

    2014-07-29

    We investigated the adhesion of two functional groups to ?-alumina as a model for the adsorption of organic molecules on clay minerals. Interactions between organic compounds and clay minerals play an important role in processes such as drinking water treatment, remediation of contaminated soil, oil recovery, and fabricating complicated nanomaterials, and there have been claims that organic compound-clay mineral interaction created the ordering that is necessary for the genesis of life. In many organisms, interaction between organic molecules and biominerals makes it possible to control the growth of bones, teeth, and shells. Adhesion of carboxylic acid, -COO(H), and pyridine, -C5H5N(H(+)), on the {0001} plane of ?-alumina wafers has been investigated with atomic force microscopy (AFM) in chemical force mapping (CFM) mode. Both functional groups adhered to ?-alumina in deionized water at pH < 5, and adhesion decreased as NaCl or CaCl2 concentration increased. X-ray photoelectron spectroscopy (XPS) showed that Na(+) and Ca(2+) adsorbed to the ?-alumina surface at pH < 5, decreasing surface interaction with the carboxylic acid and pyridine groups. We interpret the results as evidence that the tips adhere to alumina through hydrogen bonding when only water is present. In solutions containing NaCl and CaCl2, cations are adsorbed but Cl(-) is not. When NaCl solutions are replaced by CaCl2, Ca(2+) replaces Na(+), but rinsing with ultrapure deionized water (pH 5.6) could not restore the original protonated surface. The results demonstrate that the alumina surface at pH 3 has a higher affinity for inorganic cations than for -COO(H) or -C5H5N(H(+)), in spite of the known positive surface charge of ?-alumina {0001} wafers. These results demonstrate that solution salinity plays an important role in surface properties, controlling surface tension (i.e., contact angle) and adsorption affinity on ?-alumina and, by analogy, on clay minerals. PMID:24988276

  5. The adsorption refrigeration characteristics of alkaline-earth metal chlorides and its composite adsorbents

    Microsoft Academic Search

    L. Wang; L. Chen; H. L. Wang; D. L. Liao

    2009-01-01

    A study was conducted on the adsorption characteristics of the adsorption refrigeration working pairs using alkaline-earth metal chlorides as adsorbents and ammonia as refrigerant. The adsorption isotherms between alkaline-earth metal chlorides and nitrogen were studied. The study shows that the adsorbents of CaCl2, SrCl2 provide better adsorption capability associated with ammonia when compared to that of MgCl2, BaCl2. CaSO4 was

  6. Intermediate-conductance calcium-activated potassium channel KCa3.1 and chloride channel modulate chemokine ligand (CCL19/CCL21)-induced migration of dendritic cells.

    PubMed

    Shao, Zhifei; Gaurav, Rohit; Agrawal, Devendra K

    2015-07-01

    The role of ion channels is largely unknown in chemokine-induced migration in nonexcitable cells such as dendritic cells (DCs). Here, we examined the role of intermediate-conductance calcium-activated potassium channel (KCa3.1) and chloride channel (CLC3) in lymphatic chemokine-induced migration of DCs. The amplitude and kinetics of chemokine ligand (CCL19/CCL21)-induced Ca(2+) influx were associated with chemokine receptor 7 expression levels, extracellular-free Ca(2+) and Cl(-), and independent of extracellular K(+). Chemokines (CCL19 and CCL21) and KCa3.1 activator (1-ethyl-1,3-dihydro-2H-benzimidazol-2-one) induced plasma membrane hyperpolarization and K(+) efflux, which was blocked by 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole, suggesting that KCa3.1 carried larger conductance than the inward calcium release-activated calcium channel. Blockade of KCa3.1, low Cl(-) in the medium, and low dose of 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) impaired CCL19/CCL21-induced Ca(2+) influx, cell volume change, and DC migration. High doses of DIDS completely blocked DC migration possibly by significantly disrupting mitochondrial membrane potential. In conclusion, KCa3.1 and CLC3 are critical in human DC migration by synergistically regulating membrane potential, chemokine-induced Ca(2+) influx, and cell volume. PMID:25583444

  7. Ion-pairing in aqueous CaCl2 and RbBr solutions: simultaneous structural refinement of XAFS and XRD data

    SciTech Connect

    Pham, Thai V.; Fulton, John L.

    2013-01-28

    We present a new methodology involving the simultaneous refinement of both x-ray absorption and x-ray diffraction spectra (X-ray Absorption/Diffraction Structural Refinement,XADSR), to study hydration and ion pair structure of CaCl2 and RbBr salts in concentrated aqueous solutions. The XADSR analysis includes the XAFS spectra analysis of both the cation and anion as a probe of their short-range structure with an XRD spectral analysis as a probe of the global structural. Together they deliver a comprehensive picture of the cation and anion hydration, the contact ion pair (CIP) structure and the solvent-separated ion pair (SSIP) structure. XADSR analysis of 6.0 m aqueous CaCl2 reveals that there are an insignificant number of Ca2+-Cl- CIP’s, but there are approximately 3.4 SSIP’s separated by about 4.99 Å. In contrast XADSR analysis of aqueous RbBr yields about 0.7 pair CIP at a bond length 3.51 Å. The present work demonstrates a new approach for a direct co-refinement of XRD and XAFS spectra in a simple and reliable fashion, opening new opportunities for analysis in various disordered and crystalline systems. This work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is operated for the U.S. Department of Energy by Battelle.

  8. Negative Chronotropic and Antidysrhythmic Effects of Hydroalcoholic Extract of Lemon Balm (Melissa Officinalis L.) on CaCl2-Induced Arrhythmias in Rats

    PubMed Central

    Akhondali, Zahra; Dianat*, Mahin; Radan, Maryam

    2015-01-01

    Background: In many cases, myocardial infarction leads to arrhythmia. Since antioxidant agents have an important protective role in heart disease, these compounds in medicinal plants are used in traditional medicine. Lemon balm extract, compared to other plants of the lamiaceae family, has been proven to have significant amounts of antioxidant compounds. The aim of this study was to assess the effect of the hydroalcoholic extract of lemon balm (Melissa officinalis L.) on CaCl2-induced arrhythmias in rats. Methods: This research is an experimental study; male adult Sprague Dawley rats that weighed 200-250 g were divided randomly into three groups, i.e., 1) control (normal saline, 1 ml/kg/day), 2) extract (100 mg/kg), and 3) extract (200 mg/kg). The normal saline and the extracts were gavaged for 14 consecutive days. After anesthesia, lead II electrocardiograms were recorded for calculating the rats’ heart rates (HRs). Arrhythmia was induced by intravenous injection of CaCl2 solution (140 mg/kg), and the percentages of incidence of ventricular tachycardia (VT), ventricular fibrillation (VF), and ventricular premature beats (VPB) were recorded. The results were analyzed by using Fisher’s exact test and one-way ANOVA. P-values less than 0.05 were considered as significant level. Results: Heart rates and percentages of incidence of VPB, VT, and VF were reduced significantly in extract groups (with the highest activity at 200 mg/kg) in comparison with the control group. Conclusion: Melissa officinalis was considered to be an antiarrhythmic agent because it reduced the percentage of incidence of VPB, VT, and VF in the groups that received it. The results indicated that Melissa officinalis had a protective effect on the heart. PMID:26052407

  9. EDTA-insoluble, calcium-binding proteoglycan in bovine bone

    Microsoft Academic Search

    Y. Hashimoto; G. E. Lester; B. Caterson; M. Yamauchi

    1995-01-01

    A calcium ion precipitable, trypsin-generated proteoglycan fragment has been isolated from the demineralized, EDTA-insoluble matrices of bone. The demineralized matrix was completely digested with trypsin, increasing concentrations of CaCl2 were added to the supernatant, and the resulting precipitates were analyzed. The amount of precipitate gradually increased with higher concentrations of calcium and was reversibly solubilized by EDTA. After molecular sieve

  10. Calcium oxyhalide batteries - a review

    Microsoft Academic Search

    Peled

    1983-01-01

    The electrochemistry, safety aspects and performance of calcium-thionyl chloride (TC) and calcium sulfuryl chloride (SC) batteries containing lithium or calcium based electrolytes are reviewed. In Ca -oxyhalide solutions, the calcium anode is covered by CaClâ passivating layer which is a good ionic conductor and good electronic insulator. Therefore it is called Solid Electrolyte Interphase (SEI) and these batteries are called

  11. Heat stability and calcium bioavailability of calcium-fortified milk

    Microsoft Academic Search

    G. Singh; S. Arora; G. S. Sharma; J. S. Sindhu; V. K. Kansal; R. B. Sangwan

    2007-01-01

    The objective of the study was to fortify calcium in cow milk in order to prepare calcium-enriched heat-stable milk for individuals who may not ingest enough calcium to meet minimum daily requirements. Therefore, cow milk was fortified with calcium at the rate of 50mg\\/100ml using three salts of calcium, viz. calcium chloride, calcium lactate and calcium gluconate. Upon addition of

  12. Effectiveness of hydrothermal-calcium chloride treatment and chitosan on quality retention and microbial growth during storage of fresh-cut papaya.

    PubMed

    Ayón-Reyna, Lidia E; Tamayo-Limón, Ransés; Cárdenas-Torres, Feliznando; López-López, Martha E; López-Angulo, Gabriela; López-Moreno, Héctor S; López-Cervántes, Jaime; López-Valenzuela, José A; Vega-García, Misael O

    2015-03-01

    Rapid degradation of fresh-cut papaya limits its marketability. Hydrothermal treatments in combination with a calcium dip, applied to whole fruit before slicing, and also the application of chitosan as a coating film, have been found to have very good results in maintaining the quality of fresh-cut fruits. Based on these considerations, the aim of this study was to evaluate the effect of hydrothermal treatment (HT; 49 °C, 25 min) containing calcium chloride (Ca; 1%, w/v) followed by dipping in chitosan (Chit; 1%, w/v, 3 min) on the physical, chemical, and microbial qualities of papaya slices stored at 5 °C for 10 d. Pulp color, firmness, ascorbic acid, total phenolics, ?-carotene, and lycopene were evaluated every 2 d while the microbial quality (mesophilics, psychrophilics, molds, and yeasts) was evaluated every 5 d. Fruit treated with HT-Ca and HT-Ca + Chit showed better color and firmness retention than Control and Chit. Papaya slices treated with HT-Ca + Chit had higher nutritional content and lower microbial growth at the end of storage. The application of the HT-Ca + Chit could be used to reduce deterioration processes, maintaining physical, chemical, and microbial qualities and increasing the shelf life of fresh-cut papaya stored at 5 °C. PMID:25627320

  13. Adsorption of iron oxide nanoclusters stabilized with sulfonated copolymers on silica in concentrated NaCl and CaCl2 brine.

    PubMed

    Bagaria, Hitesh G; Neilson, Bethany M; Worthen, Andrew J; Xue, Zheng; Yoon, Ki Youl; Cheng, Victoria; Lee, Jae Ho; Velagala, Sindhuja; Huh, Chun; Bryant, Steven L; Bielawski, Christopher W; Johnston, Keith P

    2013-05-15

    Transport of metal oxide nanoparticles in porous rock is of interest for imaging and oil recovery in subsurface reservoirs, which often contain concentrated brine. Various copolymers composed of acrylic acid and either 2-acrylamido-2-methylpropanesulfonate or styrenesulfonate were synthesized and adsorbed on iron oxide nanoclusters to provide colloidal stability and to achieve low adsorption on silica in high salinity brine composed of 8%wt. NaCl+2%wt. CaCl2. Furthermore, the degree of adsorption of the nanoparticles on silica was controlled by modifying the acrylic acid groups in the copolymers with a series of diamines and triamines to add hydrophobicity. The adsorption on colloidal silica microparticles ranged from <1 mg/m(2) for highly charged hydrophilic surfaces on the iron oxide nanoparticles to 22 mg/m(2) for the most hydrophobic amine-modified surfaces, corresponding to monolayer coverages that ranged from 0.2% to 11.5%, respectively. The specific adsorption (mg-IO/m(2)-silica), monolayer coverage, and parameters for Langmuir isotherms were evaluated for various IO nanoclusters as a function of the properties of the copolymers on their surfaces. PMID:23473572

  14. Two different effects of calcium on aquaporins in salinity-stressed pepper plants

    Microsoft Academic Search

    M. Carmen Martínez-Ballesta; Francisco Cabañero; Enrique Olmos; Paula María Periago; Christophe Maurel; Micaela Carvajal

    2008-01-01

    Two different effects of calcium were studied, respectively, in plasma membrane vesicles and in protoplasts isolated from\\u000a roots of control pepper plants (Capsicum annuum L cv. California) or of plants treated with 50 mM NaCl, 10 mM CaCl2 or 10 mM CaCl2 + 50 mM NaCl. Under saline conditions, osmotic water permeability (P\\u000a \\u000a f\\u000a ) values decreased in protoplasts and plasma membrane vesicles, and the same

  15. Regulation of the sodium/potassium/chloride cotransporter by calcium and cyclic AMP in cultured vascular smooth muscle cells

    SciTech Connect

    Higgins, B.L.; Smith, L.; Smith, J.B.

    1987-05-01

    The activity of the Na/K/Cl cotransporter in smooth muscle cells cultured from rat aorta was assayed by measuring the initial rate of furosemide-inhibitable /sup 86/Rb influx or efflux. Five uM furosemide or 0.2 uM bumetanide inhibited influx by 50%. Furosemide-inhibitable /sup 86/Rb influx depended on the presence of all 3 ions in the external medium. The dependence on Na and K was hyperbolic with apparent Km values of 45 and 5 mM, respectively. The dependence on Cl was sigmoidal. Assuming a stoichiometry of 1:1:2 for Na:K:Cl, a Km for Cl of 60 mM was obtained from a Hofstee plot of the data. Rapidly growing cells had 3 fold higher cotransport activity than quiescent cells. Angiotensin II (ANG) stimulated furosemide-inhibitable /sup 86/Rb efflux by 2 fold. An ANG receptor antagonist prevented ANG from increasing cotransport activity. Two calcium ionophores, A23187 and ionomycin, increased cotransport activity by 2 fold. Phorbol myristate acetate had no effect on cotransport activity. Isoproterenol, dibutyryl cyclic AMP, cholera toxin, or methylisobutylxanthine inhibited furosemide-sensitive /sup 86/Rb influx by 35 to 50%. From these findings they conclude that increasing cytoplasmic free calcium stimulates cotransport activity, whereas increasing cellular cyclic AMP inhibits the cotransporter.

  16. Immediate acceptance of minerals and HCl by calcium-deprived rats: brief exposure tests.

    PubMed

    Coldwell, S E; Tordoff, M G

    1996-07-01

    We conducted two experiments to test the hypothesis that calcium consumption by calcium-deprived rats is unlearned and guided by oral cues. In experiment 1, we gave 23.5-h water-deprived control and calcium-deprived rats 30-min tests with water and various taste solutions. Relative to controls, calcium-deprived rats licked significantly less water and more 300 mM Ca.lactate in the first minute, more 50 mM HCl and 125 mM HCl in the first 10 min, and more 75 mM CaCl2, 150 mM CaCl2, and 300 mM CaCl2 by the end of the 30-min session. There was no difference between the groups at any time in lick rates for sodium solutions, quinine hydrochloride, sucrose octaacetate, or saccharin. In experiment 2, we gave 23-h water-deprived control, calcium-deprived, and sodium-deprived rats 10-min tests. During the first minute, calcium-deprived rats licked more than did control and sodium-deprived rats for 100 mM CaCl2, 100 mM FeCl2, and 20 mM Pb.acetate. Sodium-deprived rats licked more than did control and calcium-deprived rats for 600 mM NaCl and less than did controls for 200 mM L-histidine. At the end of the 10-min session, sodium-deprived rats had higher lick rates for 100 mM FeCl2 than did control rats. There were no differences between the groups in lick rates for 1 mM quinine hydrochloride, 100 mM SrCl2, or 20 mM citric acid. The results suggest that calcium-deprived rats use innate oral factors to guide consumption of calcium and other solutions. PMID:8760198

  17. Activation of potassium currents by inhibitors of calcium-activated chloride conductance in rabbit portal vein smooth muscle cells.

    PubMed Central

    Toma, C.; Greenwood, I. A.; Helliwell, R. M.; Large, W. A.

    1996-01-01

    1. The conventional whole-cell recording technique was used to study the effects of the chloride channel inhibitors ethacrynic acid, anthracene-9-carboxylic acid (A-9-C) and indanyloxyacetic acid (IAA) on membrane currents in rabbit portal vein smooth muscle cells at a holding potential of 0 mV. 2. Using a pipette solution that contained 1 x 10(-4) M 1,2-bis (2-aminophenoxy)-ethane-N,N,N,N,-tetraacetic acid (BAPTA) and a normal bathing solution the addition of ethacrynic acid (2 x 10(-4) M to 1 x 10(-3) M) inhibited spontaneous transient outward currents (STOCs) and evoked a concentration-dependent current at a holding potential of 0 mV. A similar current was activated by IAA (5 x 10(-4) M to 1 x 10(-3) M) but not by A-9-C (1-5 x 10(-3) M) at a holding potential of 0 mV. 3. The amplitude of the current evoked by ethacrynic acid and IAA was linearly related to potential between -30 and 0 mV and displayed outward rectification at positive potentials. The current induced by A-9-C was evident only at potentials positive to +20 mV. 4. Glibenclamide (1 x 10(-5) M) abolished the current evoked by ethacrynic acid and IAA at potentials negative to +10 mV and partially inhibited the current positive to +10 mV. The glibenclamide-insensitive current at positive potentials was completely inhibited by 1 x 10(-3) M TEA. The A-9-C-evoked current was insensitive to glibenclamide and abolished by 1 x 10(-3) M TEA. 5. The glibenclamide-sensitive current activated by ethacrynic acid was not sustained and declined to control levels in the continued presence of ethacrynic acid. However, the outwardly rectifying current recorded at +50 mV was well maintained over the same period. 6. Outwardly rectifying currents evoked by ethacrynic acid and A-9-C were observed with a pipette solution containing 1 x 10(-2) M BAPTA in cells bathed in Ca-free extracellular solution containing 5 x 10(-4) M BAPTA and 1 x 10(-5) M cyclopiazonic acid. 7. It is concluded that all three chloride-channel blockers activated an outwardly rectifying, TEA-sensitive current. Moreover, ethacrynic acid and IAA evoked an additional glibenclamide-sensitive current which was present at all potentials between -30 and +50 mV. PMID:8762072

  18. Environmentally assisted cracking behavior of single and dual phase stainless steels in hot chloride solutions

    Microsoft Academic Search

    Chuan-Ming Tseng; Wen-Ta Tsai

    2004-01-01

    The environmentally assisted cracking (EAC) behavior of AISI 316L austenitic stainless steel (SS), AISI 430 ferritic stainless steel and 22% Cr duplex stainless steel (DSS) in hot chloride solutions were investigated. Slow strain rate testing (SSRT) technique was employed to evaluate the susceptibility to EAC in 3.5wt.% NaCl solution at 80°C and in 40wt.% CaCl2 solution at 100°C. The experimental

  19. Deep formation waters of Western Europe, Russia and North America characterised by sodium, calcium, magnesium and chloride concentrations

    NASA Astrophysics Data System (ADS)

    Bozau, Elke; Hemme, Christina; Sattler, Carl-Diedrich; van Berk, Wolfgang

    2015-04-01

    Deep formation water can be classified according to depth, temperature, and salinity (e.g., Graf et al. 1966, Kharaka & Hanor 2007). Most of the deep formation waters contain dissolved solids in excess of sea water. The hydrogeochemical development of formation water has been discussed for a long time. It is widely accepted that deep aquifers are influenced by the meteoric cycle and geochemical processes within the crust (e.g., Hebig et al. 2012). Similar hydrogeochemical signatures are found in deep formation waters of all continents and can be explained by general geochemical processes within the deep reservoirs (e.g., Land 1995). Therefore, data of deep formation waters from Western Europe, Russia, and North America are collected and classified by the major water components. The data are used to identify important hydrogeochemical processes (e.g., halite dissolution and albitisation) leading to different compositions of formation water. Two significant water types are identified: Na-Cl water and Na-Ca-Cl water. Based on the collected hydrogeochemical data, development trends are stated for the formation waters, and albitisation is favoured as the main process for calcium enrichment. Furthermore, differences of formation water according to stratigraphical units are shown for deep reservoirs of the North German Basin and the North Sea. References: Graf, D.L., 1982. Chemical osmosis, reverse chemical osmosis, and the origin of subsurface brines. Geochimica Cosmochimica Acta 46, 1431-1448. Hebig, K.H., Ito, N., Scheytt, T., Marui, A., 2012. Review: Deep groundwater research with focus on Germany. Hydrogeology Journal 20, 227-243. Kharaka, Y.K., Hanor, J.S., 2007. Deep fluids in continents: I. Sedimentary Basins. Treatise on Geochemistry 5, 1-48. Land, L.S., 1995. The role of saline formation water in the crustal cycling. Aquatic Geochemistry 1, 137-145. Acknowledgements: The presented data are results of the collaborative research program "gebo" (Geothermal energy and high performance drilling), financed by the Ministry of Science and Culture of the Federal State of Lower Saxony and industry partner Baker Hughes Celle.

  20. Development and validation of HTS assay for screening the calcium-activated chloride channel modulators in TMEM16A stably expressed CHO cells.

    PubMed

    Qi, Jinlong; Wang, Yuan; Liu, Yani; Zhang, Fan; Guan, Bingcai; Zhang, Hailin

    2014-02-01

    Calcium-activated chloride channels (CaCCs), for example TMEM16A, are widely expressed in a variety of tissues and are involved in many important physiological functions. We developed and validated an atomic absorption spectroscopy (AAS)-based detection system for high-throughput screening (HTS) of CaCC modulators. With this assay, Cl(-) flux from CHO cells stably transfected with TMEM16A is assayed indirectly, by measuring excess silver ions (Ag(+)) in the supernatant of AgCl precipitates. The screening process involved four steps: (1) TMEM16A CHO cells were incubated in high-K(+) and high-Cl(-) buffer with test compounds, and with ionomycin as Ca(2+) ionophore, for 12 min; (2) cells were washed with a low-K(+), Cl(-)-free and Ca(2+)-free buffer; (3) CaCC/TMEM16A were activated in high-K(+), Cl(-)-free buffer with ionomycin (10 ?mol L(-1)) for 12 min; and (4) excess Ag(+) concentration was measured using an ion channel reader (ICR, an AAS system). The assay can be used to screen CaCC activators and inhibitors at the same time. With this assay, positive control drugs, including NPPB, CaCCinh-A01, flufenamic acid (Flu) and Eact, all had good concentration-dependent effects on CaCC/TMEM16A. NPPB and CaCCinh-A01 inhibited the CaCC/TMEM16A currents completely at 300 ?mol L(-1), with IC50 values of 39.35?±?4.72 ?mol L(-1) and 6.35?±?0.27 ?mol L(-1), respectively; and Eact, activated CaCC/TMEM16A, with an EC50 value of 3.92?±?0.87 ?mol L(-1). PMID:24448969

  1. Chemistry of Metal Chloride Complexes in Aprotic Systems

    Microsoft Academic Search

    L. K. Felker; A. D. Kelmers

    1983-01-01

    A study of metal chloride solubility in aprotic solvents has been initiated. These solvent systems have very low hydrogen ion activities and thus allow chloride ion activities which are much higher than those attainable in water. The high chloride ion activities can be generated by the dissolution of soluble salts, such as calcium chloride or sodium chloride, in the aprotic

  2. Evaluation of various parameters of calcium-alginate immobilization method for enhanced alkaline protease production by Bacillus licheniformis NCIM-2042 using statistical methods.

    PubMed

    Potumarthi, Ravichandra; Subhakar, Ch; Pavani, A; Jetty, Annapurna

    2008-04-01

    Calcium-alginate immobilization method for the production of alkaline protease by Bacillus licheniformis NCIM-2042 was optimized statistically. Four variables, such as sodium-alginate concentration, calcium chloride concentration, inoculum size and agitation speed were optimized by 2(4) full factorial central composite design and subsequent analysis and model validation by a second-order regression equation. Eleven carbon, 11 organic nitrogen and seven inorganic nitrogen sources were screened by two-level Plackett-Burman design for maximum alkaline protease production by using optimized immobilized conditions. The levels of four variables, such as Na-alginate 2.78%; CaCl(2), 2.15%; inoculum size, 8.10% and agitation, 139 rpm were found to be optimum for maximal production of protease. Glucose, soybean meal and ammonium sulfate were resulted in maximum protease production at 644 U/ml, 720 U/ml, and 806 U/ml when screened for carbon, organic nitrogen and inorganic nitrogen sources, respectively, using optimized immobilization conditions. Repeated fed batch mode of operation, using optimized immobilized conditions, resulted in continuous operation for 12 cycles without disintegration of beads. Cross-sectional scanning electron microscope images have shown the growth pattern of B. licheniformis in Ca-alginate immobilized beads. PMID:17643299

  3. Relationship between free chloride and total chloride contents in concrete

    Microsoft Academic Search

    T. U. Mohammed; H. Hamada

    2003-01-01

    Linear relationships between free chloride and total chloride contents in concrete are proposed based on the results of several long-term exposure tests under marine environment for various cements, such as ordinary portland cement (OPC), high early strength portland cement (HES), moderate heat portland cement (MH), calcium aluminate cement (AL), slag cements of Types A (SCA) and B (SCB), and fly

  4. Refined crystal structure of Ca[B 8 O 11 (OH) 4 ]—A synthetic calcium analog of strontioborite

    Microsoft Academic Search

    N. A. Yamnova; Yu. K. Egorov-Tismenko; N. V. Zubkova; O. V. Dimitrova; A. P. Kantor

    2005-01-01

    A calcium analog of strontioborite, namely, Ca[B8O11(OH)4], is synthesized under hydrothermal conditions (T = 270C, P = 20 atm) within the framework of the study of the phase formation in the CaCl2 Rb2CO3 B2O3 system. The crystal structure of the synthetic calcium borate [a = 7.4480(5) ?, b = 8.2627(5) ?, c = 9.8102(6) ?, ? = 108.331(1), V =

  5. Synthesis of TiO 2 (Anatase) by Sol–Gel Process Performed in Metal Chlorides Saturated Aqueous Solutions

    Microsoft Academic Search

    Robson Fernandes de Farias

    2001-01-01

    Titania powders were synthesized by a sol–gel process using titanium tetrabutoxide as a precursor. The syntheses were performed in water or in saturated aqueous solutions of KCl, CaCl2, NiCl2, CoCl2, and MnCl2. It is demonstrated, by X-ray diffraction patterns of the synthesized powders that the samples obtained in saturated aqueous solutions of metal chlorides are crystalline (anatase phase) with some

  6. Effect of Azadirachta indica (neem), sodium thiosulphate and calcium chloride on changes in nitrogen transformations and inhibition of nitrification in soil incubated under laboratory conditions.

    PubMed

    Abbasi, M Kaleem; Hina, Munazza; Tahir, Majid Mahmood

    2011-03-01

    A laboratory experiment was conducted to examine the effects of nitrification inhibitors (NIs) neem seed-cake (Azadirachta indica) (NSC), sodium thiosulphate (Na?S?O?) and calcium chloride (CaCl?) on changes in NH?(+)?N, inhibition of nitrification and recovery of applied nitrogen (N) in soil. Surface soil samples of 0-15 cm were collected from an arable field, amended with urea N (UN) at the rate 200 mg N kg?¹, UN+NSC, UN+Na?S?O? and UN+CaCl? and incubated at 22°C periodically over 50 d. Soil without any amendment was used as check (control). Results indicated that more than 58% of N applied as NH?? disappeared over a period of 50 d from the soil mineral-N pool. Some of this N (21%) was accumulated as NO??-N while the remaining N was unaccounted for. Addition of nitrification inhibitors NSC, Na?S?O?, and CaCl? resulted in a decrease in the extent of NH?(+) disappearance by 35%, 44% and 30%, respectively. In the treatment receiving UN alone, 56 mg NO??-N kg?¹ was accumulated over 50 d (maximum 93 mg kg?¹) indicated an active nitrification. Application of nitrification inhibitors NSC, Na?S?O?, and CaCl? with UN inhibited nitrification by 54%, 64%, and 59%, respectively. Apparent N recovery (ANR) in the treatment receiving UN alone was 63% that substantially increased to 83%, 89% and 76% in the treatments receiving UN+NSC, UN+Na?S?O?, and UN+CaCl?, respectively indicating 32%, 41% and 20% increase in N recovery. Among three NIs tested, Na?S?O? proved superior in inhibiting nitrification and increasing ANR. The study demonstrated that application of NSC, Na?S?O?, and CaCl? which are cheap and easily available NIs inhibited nitrification and improved N recovery efficiency of applied N in an arable soil very effectively. It is suggested that these inhibitors should be tested under field conditions for increasing NUE and improving crop productivity. PMID:21146192

  7. Mechanism of Friedel's salt formation in cements rich in tri-calcium aluminate

    Microsoft Academic Search

    A. K. Suryavanshi; J. D. Scantlebury; S. B. Lyon

    1996-01-01

    In the present investigation, based on pore solution analyses, the mechanisms of Friedel's salt formation and the related chemical processes taking place in mortar due to chloride binding are dealt with. Pore solutions from mortars containing NaCl and CaCl2 added during mixing were analyzed. Based on the results it is proposed that in the presence of NaCl the Friedel's salt

  8. Local Effects in the X-ray Absorption Spectrum of CaCl2, MgCl2, and NaCl Solutions

    SciTech Connect

    Kulik, H J; Correa Tedesco, A A; Schwegler, E; Prendergast, D; Galli, G

    2010-04-12

    Both first principles molecular dynamics and theoretical X-ray absorption spectroscopy have been used to investigate the aqueous solvation of cations in 0.5 M MgCl{sub 2}, CaCl{sub 2}, and NaCl solutions. We focus here on the species-specific effects that Mg{sup 2+}, Ca{sup 2+}, and Na{sup +}, have on the X-ray absorption spectrum of the respective solutions. For the divalent cations, we find that the hydrogen bonding characteristics of the more rigid magnesium first shell water molecules differ from those in the more flexible solvation shell surrounding calcium. In particular, the first solvation shell water molecules of calcium are accessible to forming acceptor hydrogen bonds, and this results in an enhancement of a post-edge peak near 540 eV. The absence of acceptor hydrogen bonds for magnesium first shell water molecules provides an explanation for the experimental and theoretical observation of a lack of enhancement at the post-main-edge peak. For the sodium monovalent cation we find that the broad tilt angle distribution results in a broadening of post-edge features, despite populations in donor-and-acceptor configurations consistent with calcium. We also present the re-averaged spectra of the MgCl{sub 2}, CaCl{sub 2}, and NaCl solutions and show that trends apparent with increasing concentration (0.5 M, 2.0 M, 4.0 M) are consistent with experiment. Finally, we examine more closely both the effect that cation coordination number has on the hydrogen bonding network and the relative perturbation strength of the cations on lone pair oxygen orbitals.

  9. [Pretreatment technology for fly ash from MSWI and the corresponding study of chloride behavior].

    PubMed

    Zhu, Fen-Fen; Takaoka, Masaki; Oshita, Kazuyuki; Jiang, Hui-Min; Kitajima, Yoshinori

    2013-06-01

    The introduced pretreatment technology, WCCB (Washing + Calcination), was effective to reduce chlorides in fly ash by consuming relatively low energy for recycling fly ash as the raw material for cement industry. The washing conditions are: twice-washing, liquid/solid = 3, mixing speed = 150 r x min(-1), 1st mixing time = 5 min, and 2nd mixing time = 10 min. The original incinerator was used for the calcination process, 1 000 degrees C, 10% O2 and dwelling time of 1 hour were adopted. By adopting X-ray absorption near edge structure and X-ray diffraction, the behavior of chlorides was explained and NaCl, KCl and CaCl2 are the main form of chlorides existing in fly ash. The reagent used in the air pollution control system to neutralize the acid component in the discharged gas surely acted a very important role in the formation of chlorides. The insoluble chlorides in fly ash had a very similar structure as that of Friedel's salt, which was related with CaCl2. PMID:23947072

  10. Effect of cadmium on cytogenetic toxicity in hairy roots of Wedelia trilobata L. and their alleviation by exogenous CaCl2.

    PubMed

    Shi, He Ping; Zhu, Yuan Feng; Wang, Yun Ling; Tsang, Po Keung Eric

    2014-01-01

    Effects of cadmium (Cd) alone and in combination with calcium on mitosis and chromosomal aberration in the hairy root tips of Wedelia trilobata were investigated. The results showed that Cd concentrations below 50 ?mol/L had a lesser or even a promoting effect on the mitotic index (MI) and the rate of chromosomal aberration in hairy root tips, while those higher than 100 ?mol/L significantly decreased the MI and gradually stimulated the rate of chromosomal aberrations with prolonged time and increasing concentrations of Cd. Concentrations of 50 ?mol/L Cd mainly induced C-mitosis, while more than 100 ?mol/L Cd mainly caused chromosome breakage and chromosome adhesion in hairy root tip cells. When cultured with 300 ?mol/L Cd, micronuclei were only observed in the interphase, middle, and late phase of hairy root tip cells. Compared with untreated controls, exogenous calcium had an alleviating effect on Cd-induced cytotoxicity by effectively enhancing the MI and reducing the rate of chromosomal aberration in root tip cells. The results presented here provide evidence that W. trilobata hairy roots with rapid autonomous growth could be used as a sensitive tool for monitoring and evaluation of Cd pollution in the environment. PMID:23917739

  11. Vinyl Chloride

    Cancer.gov

    Vinyl chloride is a colorless gas that burns easily. It does not occur naturally and must be produced industrially for its commercial uses. Vinyl chloride is used primarily to make polyvinyl chloride (PVC); PVC is used to make a variety of plastic products, including pipes, wire and cable coatings, and packaging materials. Vinyl chloride is also produced as a combustion product in tobacco smoke.

  12. Absorption spectra of cobalt(II) chloride and nitrate complexes in aqueous calcium nitrate–ammonium nitrate melts: The influence of solvent composition

    Microsoft Academic Search

    Milan Vraneš; Slobodan B. Gadžuri?; István J. Zsigrai; Sanja Doži?

    2010-01-01

    Influence of solvent composition, i.e. the salt mole fraction and water content on absorption spectra of cobalt(II) chloride and nitrate in xCa(NO3)2·zH2O–(1?x)NH4NO3 systems was investigated by spectrophotometric method in the wavelength range 400–800nm at 55°C. On the basis of absorption spectra of cobalt(II) chloride and nitrate complexes and overall molar absorption coefficients obtained in 13 investigated systems, the geometry of

  13. [Alleviated affect of exogenous CaCl2 on the growth, antioxidative enzyme activities and cadmium absorption efficiency of Wedelia trilobata hairy roots under cadmium stress].

    PubMed

    Shi, Heping; Wang, Yunling; Tsang, PoKeung Eric; Chan, LeeWah Andrew

    2012-06-01

    In order to study the physiological mechanism of exogenous calcium on the toxicity of heavy metal cadmium (Cd) to Wedelia trilobata hairy roots, the effects of Cd alone, and in combination with different concentrations of Ca on growth, contents of soluble protein and malondialdehyde (MDA), activities of superoxide dismutase (SOD) and peroxidase (POD), Cd2+ absorption in W. trilobata hairy roots were investigated. Cd concentrations lower than 50 micromol/L enhanced the growth of hairy roots, while concentrations higher than 100 micromol/L inhibited growth, making the branched roots short and small, and also turning the root tips brown, even black. In comparison with the control (0 micromol/L Cd), the soluble protein content in hairy roots was found to increase when cultured with 10-50 micromol/L Cd, and decrease when exposed to a cadmium concentration higher than 100 micromol/L Cd. In addition, the activities of POD and SOD activity and MDA content were significantly higher than the control. Compared to the control (hairy roots cultured without 10-30 mmol/L Ca), 100 micromol/L Cd or 300 micromol/L Cd in combination with 10-30 mmol/L Ca resulted in increased growth, causing the main root and secondary roots thicker and also an increase in soluble protein content. On the contrary, MDA content and POD and SOD activities decreased. Quantitative analysis by Atomic Absorption Spectrophotometry showed that W. trilobata hairy roots can absorb and adsorb heavy metal Cd in the ionic form of Cd2+. The maximum content of Cd2+ absorbed by the hairy roots was obtained with a concentration 100 micromol/L Cd2+ while that of Cd2+ adsorbed by hairy roots was achieved with a concentration of 300 micromol/L Cd2+. The exogenous addition of 10-30 mmol/L Ca2+ was found to reduce the absorption, adsorption of Cd2+ and the toxicity of Cd significantly. This reduction in toxicity was caused by the reduction in the absorption of Cd and decreasing the lipid peroxidation through regulating the activities of antioxidant enzymes SOD and POD in the hairy roots. PMID:23016311

  14. Experimental evaluation of water mist with metal chloride additives for suppressing CH4/air cup-burner flames

    NASA Astrophysics Data System (ADS)

    Liu, Jianghong; Cong, Beihua

    2013-06-01

    In order to investigate the fire suppression effectiveness of water mist with metal chloride additives, ultrafine water mists of these salts with diameters about 10?m were introduced into CH4/air non-premixed flame in the cup burner. Results showed that these droplets hard to make itself to the flame front under the cup burner flow conditions functioned as a carrier of the vaporized solid particles or its decomposed materials. The metal chloride improved fire suppression efficacy of water mist which were affected by the type and concentration of metal chloride. On a mass basis, there is a fire suppression effectiveness relationship of MgCl2chlorides improves as the concentration of metal chlorides increase. However, upper additive limits exist due to the associated limiting vapour pressure of the additive.

  15. Remediation of cadmium- and lead-contaminated agricultural soil by composite washing with chlorides and citric acid.

    PubMed

    Li, Yu-jiao; Hu, Peng-jie; Zhao, Jie; Dong, Chang-xun

    2015-04-01

    Composite washing of cadmium (Cd)- and lead (Pb)-contaminated agricultural soil from Hunan province in China using mixtures of chlorides (FeCl3, CaCl2) and citric acid (CA) was investigated. The concentrations of composite washing agents for metal removal were optimized. Sequential extraction was conducted to study the changes in metal fractions after soil washing. The removal of two metals at optimum concentration was reached. Using FeCl3 mixed with CA, 44% of Cd and 23% of Pb were removed, and 49 and 32% by CaCl2 mixed with CA, respectively. The mechanism of composite washing was postulated. A mixture of chlorides and CA enhanced metal extraction from soil through the formation of metal-chloride and metal-citrate complexes. CA in extract solutions promoted the formation of metal-chloride complexes and reduced the solution pH. Composite washing reduced Cd and Pb in Fe-Mn oxide forms significantly. Chlorides and CA exerted a synergistic effect on metal extraction during composite washing. PMID:25342453

  16. Synthesis and thermal properties of strontium and calcium peroxides

    NASA Technical Reports Server (NTRS)

    Philipp, Warren H.; Kraft, Patricia A.

    1989-01-01

    A practical synthesis and a discussion of some chemical properties of pure strontium peroxide and calcium peroxide are presented. The general synthesis of these peroxides involves precipitation of their octahydrates by addition of H2O2 to aqueous ammoniacal Sr(NO3)2 or CaCl2. The octahydrates are converted to the anhydrous peroxides by various dehydration techniques. A new x-ray diffraction powder pattern for CaO2 x 8H2O is given from which lattice parameters a=6.212830 and c=11.0090 were calculated on the basis of the tetragonal crystal system.

  17. Study of the physical properties of calcium alginate hydrogel beads containing vineyard pruning waste for dye removal.

    PubMed

    Vecino, X; Devesa-Rey, R; Cruz, J M; Moldes, A B

    2015-01-22

    In this work the morphological and surface properties of a biocomposite formulated with vineyard pruning waste entrapped in calcium alginate hydrogel beads were studied. The formulation of the calcium alginate hydrogel beads, containing vineyard pruning waste, was based on the capacity of this green adsorbent to remove dye compounds from wastewater, observing that in the optimum condition (1.25% of cellulosic residue, 2.2% of sodium alginate and 0.475 mol L(-1) CaCl2) the percentage of dyes was reduced up to 74.6%. At lower concentration of CaCl2, high-resolution optical images show that the elongation of the vineyard-alginate biocomposite decreased, whereas the compactness increased. Moreover, higher concentrations of cellulosic residue increased the biocomposite roundness in comparison with biocomposite without the cellulosic residue. Interferometric perfilometry analysis (Ra, Rq, Rz and Rt) revealed that high concentrations of CaCl2 increased the roughness of the of the calcium alginate hydrogel beads observing vesicles in the external surface. PMID:25439877

  18. Hydrothermal Formation Of Hemi-hydrate Calcium Sulfate Whiskers In The Presence Of Additives

    NASA Astrophysics Data System (ADS)

    Luo, K. B.; Li, C. M.; Xiang, L.; Li, H. P.; Ning, P.

    2010-11-01

    The influence of addictives on the hydrothermal formation of hemi-hydrate calcium sulfate (CaSO4?0.5H2O) whiskers were discussed in this paper, using CaCl2 and Na2SO4 as the reactants. The presence of NaCl, CaCl2 or Na2SO4 increased the concentrations of Ca2+ and SO42-, leading to the formation of CaSO4?0.5H2O whiskers with aspect ratio lower than 50. The one dimensional growth of CaSO4?0.5H2O whiskers was enhanced in water with no additives owing to the low super-saturation, leading to the formation of uniform whiskers with a length of 200-2000 ?m and an aspect ratio higher than 100.

  19. Effect of meal composition on calcium absorption: enhancing effect of carbohydrate polymers

    SciTech Connect

    Kelly, S.E.; Chawla-Singh, K.; Sellin, J.H.; Yasillo, N.J.; Rosenberg, I.H.

    1984-09-01

    Meal components including fat, fiber, and carbohydrates can influence the intestinal absorption of calcium; such interactions may be of even greater importance in the presence of intestinal disease. This study compares intestinal absorption of 47CaCl2 administered in four ways: in water, within a standard meal, with a liquid formula (Ensure, Ross Laboratories, Columbus, Ohio), or with a glucose polymer solution (Frodex-15, Ross). Studies were carried out in 9 patients with ileal resection, 3 patients with jejunoileal bypass, and 14 controls. Fractional calcium absorption from water was lower in patients than in controls. Absorption was enhanced 1.5- to 5-fold when 47CaCl2 was administered with a liquid formula diet containing a glucose polymer or with the glucose polymer alone. Patients with the lowest calcium absorption from breakfast showed the greatest effect of calcium ingestion with formula or glucose polymer. These findings further emphasize the importance of meal composition on calcium absorption and provide a possible mechanism for enhancing calcium absorption in some patients with chronically impaired absorption.

  20. Increased calcium absorption from synthetic stable amorphous calcium carbonate: double-blind randomized crossover clinical trial in postmenopausal women.

    PubMed

    Vaisman, Nachum; Shaltiel, Galit; Daniely, Michal; Meiron, Oren E; Shechter, Assaf; Abrams, Steven A; Niv, Eva; Shapira, Yami; Sagi, Amir

    2014-10-01

    Calcium supplementation is a widely recognized strategy for achieving adequate calcium intake. We designed this blinded, randomized, crossover interventional trial to compare the bioavailability of a new stable synthetic amorphous calcium carbonate (ACC) with that of crystalline calcium carbonate (CCC) using the dual stable isotope technique. The study was conducted in the Unit of Clinical Nutrition, Tel Aviv Sourasky Medical Center, Israel. The study population included 15 early postmenopausal women aged 54.9 ± 2.8 (mean ± SD) years with no history of major medical illness or metabolic bone disorder, excess calcium intake, or vitamin D deficiency. Standardized breakfast was followed by randomly provided CCC or ACC capsules containing 192 mg elemental calcium labeled with 44Ca at intervals of at least 3 weeks. After swallowing the capsules, intravenous CaCl2 labeled with 42Ca on was administered on each occasion. Fractional calcium absorption (FCA) of ACC and CCC was calculated from the 24-hour urine collection following calcium administration. The results indicated that FCA of ACC was doubled (± 0.96 SD) on average compared to that of CCC (p < 0.02). The higher absorption of the synthetic stable ACC may serve as a more efficacious way of calcium supplementation. PMID:24753014

  1. Simultaneous determination of free calcium, magnesium, sodium and potassium ion concentrations in simulated milk ultrafiltrate and reconstituted skim milk using the Donnan Membrane Technique

    Microsoft Academic Search

    R. Gao; E. J. M. Temminghoff; H. P. van Leeuwen; H. J. F. van Valenberg; M. D. Eisner

    2009-01-01

    This study focused on determination of free Ca2+, Mg2+, Na+ and K+ concentrations in a series of CaCl2 solutions, simulated milk ultrafiltrate and reconstituted skim milk using a recently developed Donnan Membrane Technique (DMT). A calcium ion selective electrode was used to compare the DMT results. The study showed that the free Ca2+ concentrations measured by the DMT agreed well

  2. EDTA-insoluble, calcium-binding proteoglycan in bovine bone

    NASA Technical Reports Server (NTRS)

    Hashimoto, Y.; Lester, G. E.; Caterson, B.; Yamauchi, M.

    1995-01-01

    A calcium ion precipitable, trypsin-generated proteoglycan fragment has been isolated from the demineralized, EDTA-insoluble matrices of bone. The demineralized matrix was completely digested with trypsin, increasing concentrations of CaCl2 were added to the supernatant, and the resulting precipitates were analyzed. The amount of precipitate gradually increased with higher concentrations of calcium and was reversibly solubilized by EDTA. After molecular sieve and anion exchange chromatography, a proteoglycan-containing peak was obtained. Immunochemical analysis showed that this peak contained chondroitin 4-sulfate and possibly keratan sulfate. Amino acid analysis showed that this proteoglycan contained high amounts of aspartic acid/asparagine (Asx), serine (Ser), glutamic acid/glutamine (Glx), proline (Pro), and glycine (Gly); however, it contained little leucine (Leu) which suggests that it is not a member of the leucine-rich small proteoglycan family. In addition, significant amounts of phosphoserine (P-Ser) and hydroxyproline (Hyp) were identified in hydrolysates of this fraction. A single band (M(r) 59 kDa) was obtained on SDS-PAGE that stained with Stains-all but not with Coomassie Brilliant Blue R-250. If bone powder was trypsinized prior to demineralization, this proteoglycan-containing fraction was not liberated. Collectively, these results indicate that a proteoglycan occurs in the demineralized matrix that is precipitated with CaCl2 and is closely associated with both mineral and collagen matrices. Such a molecule might facilitate the structural network for the induction of mineralization in bone.

  3. Prostaglandin E2 induces chloride secretion through crosstalk between cAMP and calcium signaling in mouse inner medullary collecting duct cells.

    PubMed

    Rajagopal, Madhumitha; Thomas, Sheela V; Kathpalia, Paru P; Chen, Yu; Pao, Alan C

    2014-02-01

    Under conditions of high dietary salt intake, prostaglandin E2 (PGE2) production is increased in the collecting duct and promotes urinary sodium chloride (NaCl) excretion; however, the molecular mechanisms by which PGE2 increases NaCl excretion in this context have not been clearly defined. We used the mouse inner medullary collecting duct (mIMCD)-K2 cell line to characterize mechanisms underlying PGE2-regulated NaCl transport. When epithelial Na(+) channels were inhibited, PGE2 exclusively stimulated basolateral EP4 receptors to increase short-circuit current (Isc(PGE2)). We found that Isc(PGE2) was sensitive to inhibition by H-89 and CFTR-172, indicating that EP4 receptors signal through protein kinase A to induce Cl(-) secretion via cystic fibrosis transmembrane conductance regulator (CFTR). Unexpectedly, we also found that Isc(PGE2) was sensitive to inhibition by BAPTA-AM (Ca(2+) chelator), 2-aminoethoxydiphenyl borate (2-APB) (inositol triphosphate receptor blocker), and flufenamic acid (FFA) [Ca(2+)-activated Cl(-) channel (CACC) inhibitor], suggesting that EP4 receptors also signal through Ca(2+) to induce Cl(-) secretion via CACC. Additionally, we observed that PGE2 stimulated an increase in Isc through crosstalk between cAMP and Ca(2+) signaling; BAPTA-AM or 2-APB inhibited a component of Isc(PGE2) that was sensitive to CFTR-172 inhibition; H-89 inhibited a component of Isc(PGE2) that was sensitive to FFA inhibition. Together, our findings indicate that PGE2 activates basolateral EP4 receptors and signals through both cAMP and Ca(2+) to stimulate Cl(-) secretion in IMCD-K2 cells. We propose that these signaling pathways, and the crosstalk between them, may provide a concerted mechanism for enhancing urinary NaCl excretion under conditions of high dietary NaCl intake. PMID:24284792

  4. The ultra-high lime with aluminum process for removing chloride from recirculating cooling water 

    E-print Network

    Abdel-wahab, Ahmed Ibraheem Ali

    2004-09-30

    Chloride is a deleterious ionic species in cooling water systems because it is important in promoting corrosion. Chloride can be removed from cooling water by precipitation as calcium chloroaluminate using ultra-high lime ...

  5. The ultra-high lime with aluminum process for removing chloride from recirculating cooling water

    E-print Network

    Abdel-wahab, Ahmed Ibraheem Ali

    2004-09-30

    Chloride is a deleterious ionic species in cooling water systems because it is important in promoting corrosion. Chloride can be removed from cooling water by precipitation as calcium chloroaluminate using ultra-high lime with aluminum process (UHLA...

  6. Calcium supplements

    MedlinePLUS

    ... The two main forms of calcium pills are: Calcium carbonate: Over-the-counter antacid products, such as Tums and Rolaids contain calcium carbonate. These sources of calcium carbonate do not cost ...

  7. Salt Brine Blending to Optimize Deicing and Anti-icing Performance and Cost

    E-print Network

    Minnesota, University of

    Salt Brine Blending to Optimize Deicing and Anti-icing Performance and Cost Effectiveness Stephen J in Method? #12;Deicing and Anti-icing Treatments ·Sodium Chloride (NaCl) ·Cargill, NA Salt ·Magnesium Chloride (MgCl2) w/additives ·Envirotech Serv., Scotwood Ind., NA Salt ·Calcium Chloride (CaCl2) ·Tiger

  8. Evaluation of PFP Furnace Systems for Thermal Stabilization of Washed High Chloride Plutonium Oxide Items

    SciTech Connect

    Fischer, Christopher M.; Elmore, Monte R.; Schmidt, Andrew J.; Gerber, Mark A.; Muzatko, Danielle S.; Gano, Susan R.; Thornton, Brenda M.

    2002-12-17

    High chloride content plutonium (HCP) oxides are impure plutonium oxide scrap which contains NaCl, KCl, MgCl2 and/or CaCl2 salts at potentially high concentrations and must be stabilized at 950 C per the DOE Standard, DOE-STD-3013-2000. The chlorides pose challenges to stabilization because volatile chloride salts and decomposition products can corrode furnace heating elements and downstream ventilation components. A high-temperature furnace (same make and model as used at the RMC at Plutonium Finishing Plant) and the associated offgas system were set up at PNNL to identify system vulnerabilities and to investigate alternative materials and operating conditions that would mitigate any corrosion and plugging of furnace and offgas components. The key areas of interest for this testing were the furnace heating elements, the offgas line located inside the furnace, the offgas line between the furnace and the filter/knockout pot, the filter/knockout pot, the sample boat, and corrosion coupons to evaluate alternative materials of construction. The evaluation was conducted by charging the furnace with CeO2 that had been impregnated with a mixture of chloride salts (selected to represent the expected residual chloride salt level in washed high chloride items) and heated in the furnace in accordance with the temperature ramp rates and hold times used at PFP.

  9. The taste of calcium and magnesium salts and anionic modifications

    Microsoft Academic Search

    Harry T. Lawless; Frank Rapacki; John Horne; April Hayes

    2003-01-01

    Taste properties of divalent salts are complex. The first study examined the taste profiles of calcium chloride, magnesium chloride and magnesium sulfate. These divalent cation salts were characterized primarily by bitter taste, with additional sensations described as salty, metallic, astringent, sour and sweet, generally in decreasing order of intensity. A second study examined the taste properties of calcium salts other

  10. Polyfluoroalkanesulfenyl chlorides

    Microsoft Academic Search

    A Yu Sizov; Aleksei F Kolomiets; Alexandr V Fokin

    1992-01-01

    Data appearing since 1975 are correlated for the methods of synthesis of polyfluoroalkanesulfenyl chlorides, their reactions with O-, S-, N-, P- and C-nucleophiles, with unsaturated aromatic and heteroaromatic compounds, for their behaviour in oxidation and heterocyclisation reactions and in free radical conversions. The bibliography includes 214 references.

  11. [Calcium--essential for everybody].

    PubMed

    Cichosz, Grazyna; Czeczot, Hanna

    2014-06-01

    Calcium regulates majority of metabolic processes within human organism and its optimal intake decreases risk of metabolic illnesses conditioned by diet. Deficiency of calcium results in higher body max index, increase risk of insulin resistance, diabetes type 2 and osteoporosis. Diet delivering full calcium load diminished impendency of hypertension; calcium regulates tension of smooth muscles of blood vessels, limits neurotransmitters activity and also diminish hazardous activity of sodium chloride. Anticancerogenic activity of calcium results from formation insoluble bile acids and fat acids salts, and most of all, from inhibition of intestine mucosa cells hyper proliferation. Due to presence of vitamin D3, CLA, proteins and bioactive peptides emerging from them, milk is more efficient in prophylaxis of diet conditioned illnesses than calcium supplements. Efficiency of milk and dairy products in treatment of obesity, sclerosis and hypertension has been proved by DASH diet. PMID:25095643

  12. Effect of sodium and calcium ingestion on thermoregulation during exercise in man

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Brock, P. J.; Morse, J. T.; Van Beaumont, W.; Montgomery, L. D.; Convertino, V. A.; Mangseth, G. R.

    1978-01-01

    The effects of hypertonic sodium and calcium ingestion on body temperature during exercise in cool and hot environments are investigated. Rectal and mean skin temperatures, sweat rates and arm and leg total blood flows were measured in men during periods of rest, submaximal exercise and recovery at temperatures of 26.5 C and 39.4 C after ingestion of NaCl and CaCl2 solutions. In both environments, higher rectal temperatures are observed after hypertonic sodium ingestion, which is also associated with attenuated blood flow in the extremities, lower sweat rates and slightly higher skin temperature in the heat, indicating significant thermoregulatory responses. Hypertonic calcium and isotonic sodium cause no temperature change, although calcium caused a reduction of blood flow in the extremities.

  13. Arctigenin exhibits relaxation effect on bronchus by affecting transmembrane flow of calcium.

    PubMed

    Zhao, Zhenying; Yin, Yongqiang; Wang, Zengyong; Fang, Runping; Wu, Hong; Jiang, Min; Bai, Gang; Luo, Guo'an

    2013-12-01

    Arctigenin, a lignan extract from Arctium lappa (L.), exhibits anti-inflammation, antioxidation, vasodilator effects, etc. However, the effects of arctigenin on bronchus relaxation are not well investigated. This study aimed to investigate how arctigenin regulates bronchus tone and calcium ion (Ca(2+)) flow. Trachea strips of guinea pigs were prepared for testing the relaxation effect of arctigenin to acetylcholine, histamine, KCl, and CaCl2, respectively. Furthermore, L-type calcium channel currents were detected by patch-clamp, and intracellular Ca(2+) concentration was detected by confocal microscopy. The results showed that arctigenin exhibited relaxation effect on tracheae to different constrictors, and this was related to decreasing cytoplasmic Ca(2+) concentration by inhibiting Ca(2+) influx partly through L-type calcium channel as well as promoting Ca(2+) efflux. In summary, this study provides new insight into the mechanisms by which arctigenin exhibits relaxation effect on bronchus and suggests its potential use for airway disease therapy. PMID:24114345

  14. 21 CFR 184.1193 - Calcium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...humectant as defined in § 170.3(o)(16) of this chapter; nutrient supplement as defined in § 170.3(o)(20) of this chapter...170.3(n)(29) of this chapter; 2.0 percent for plant protein products as defined in § 170.3(n)(33) of...

  15. Calcium oxalate crystallization kinetics from calorimetric measurements

    Microsoft Academic Search

    O. Söhnel; M. Kroupa; G. Franková; V. Velich

    1997-01-01

    The kinetics of calcium oxalate monohydrate precipitation effected by mixing aqueous solutions of calcium chloride and sodium oxalate together in the stoichiometric ratio at 25 and 37°C, were studied using an isoperibolic reaction twin calorimeter. A method for inferring the crystal growth kinetic parameters from experimental progress curve giving the time development of the integral heat evolved during the precipitation

  16. 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 ...

  17. Antibacterial and bioactive calcium titanate layers formed on Ti metal and its alloys.

    PubMed

    Kizuki, Takashi; Matsushita, Tomiharu; Kokubo, Tadashi

    2014-07-01

    An antibacterial and bioactive titanium (Ti)-based material was developed for use as a bone substitute under load-bearing conditions. As previously reported, Ti metal was successively subjected to NaOH, CaCl2, heat, and water treatments to form a calcium-deficient calcium titanate layer on its surface. When placed in a simulated body fluid (SBF), this bioactive Ti formed an apatite layer on its surface and tightly bonded to bones in the body. To address concerns regarding deep infection during orthopedic surgery, Ag(+) ions were incorporated on the surface of this bioactive Ti metal to impart antibacterial properties. Ti metal was first soaked in a 5 M NaOH solution to form a 1 ?m-thick sodium hydrogen titanate layer on the surface and then in a 100 mM CaCl2 solution to form a calcium hydrogen titanate layer via replacement of the Na(+) ions with Ca(2+) ions. The Ti material was subsequently heated at 600 °C for 1 h to transform the calcium hydrogen titanate into calcium titanate. This heat-treated titanium metal was then soaked in 0.01-10 mM AgNO3 solutions at 80 °C for 24 h. As a result, 0.1-0.82 at.% Ag(+) ions and a small amount of H3O(+) ions were incorporated into the surface calcium titanate layers. The resultant products formed apatite on their surface in an SBF, released 0.35-3.24 ppm Ag(+) ion into the fetal bovine serum within 24 h, and exhibited a strong antibacterial effect against Staphylococcus aureus. These results suggest that the present Ti metals should exhibit strong antibacterial properties in the living body in addition to tightly bonding to the surrounding bone through the apatite layer that forms on their surfaces in the body. PMID:24682896

  18. The effect of postharvest calcium application on tissue calcium concentration, quality attributes, incidence of flesh browning and cell wall physicochemical aspects of peach fruits

    Microsoft Academic Search

    G. A. Manganaris; M. Vasilakakis; G. Diamantidis; I. Mignani

    2007-01-01

    The effects of postharvest calcium applications on cell wall properties and quality attributes of peach fruits (Prunus persica L. Batsch, cv. ‘Andross’) after harvest or cold storage up to 4 weeks were determined. The fruits were immersed in deionised water or in different calcium sources (calcium chloride, calcium lactate and calcium propionate) at two calcium concentrations (62.5 and 187.5mM Ca).

  19. Jejunal calcium permeability in laying hens during egg formation

    E-print Network

    Paris-Sud XI, Université de

    Jejunal calcium permeability in laying hens during egg formation Y. NYS, P. MONGIN Station de to water, calcium, potassium, sodium and chloride was measured in the immature pullet and then in the laying hen before and during egg-shell calcification by an in vivo perfusion procedure. Jejunal calcium

  20. Effect of chloride salts, curing compounds and heating and freezing on Trichinella spiralis in pork products 

    E-print Network

    Kayfus, Timothy Jon

    1981-01-01

    shoulders were used to make linked pork sausage. Phase one of this study used chloride salt replacements calculated to an ionic strength equivalent to that of sodium chloride (2, 5/). Phase two of this study consisted of sodium chloride replace- ments.... The use of 1. 35X magnesium chloride or 1. 58/ calcium chloride de- creased (P&0. 05) pH in comparison to that for sausages made with either sodium chloride or potassium chloride. The addition of 75 or 150 porn N02 did not lower plate counts (P&0. 05...

  1. The influence of sulphates on chloride binding and pore solution chemistry

    SciTech Connect

    Xu, Y. [University College of London (United Kingdom). Dept. of Civil and Environmental Engineering] [University College of London (United Kingdom). Dept. of Civil and Environmental Engineering

    1997-12-01

    Ordinary Portland cement (OPC) and OPC/ground granulated blast furnace slag (GGBS) 65% cements containing 2.0 to 9.0% sulphates derived from sodium sulphate and calcium sulphate were investigated in respect to their chloride binding properties and the concentrations of chloride and hydroxyl ions in the pore solutions. Chlorides derived from sodium and calcium chlorides were introduced at the time of mixing. The results indicate that calcium sulphate has a different effect on chloride binding and the pore solution chemistry than sodium sulphate. The slag cement has higher chloride binding capacities as a result of simple replacement for OPC, but at the same sulphate contents, the slag cement does not give the expected higher binding capacities, suggesting that the difference in sulphate content between the two cements may be the main reason for their different chloride binding behavior.

  2. Comparative Analysis of Cement and Lateralite on the Engineering Properties of Niger Delta Soils for Pavement Construction

    E-print Network

    Alayaki, F. M.; Al-Tabbaa, A.; Meshida, E. A.; Ayotamuno, M. J.

    2015-05-13

    -lime and Calcium Chloride (CaCl2) independently and then added cement to improve the strength. 10.7% of slake-lime and 6% of CaCl2 were found adequate to achieve non-swelling soil condition of 2.5% maximum free swell as postulated by [9] and CaCl2... and Conformity Criteria for Common Cements; 2000. BSI 9 July 2004, ISBN 0 580 36456 9. 18. Kosmatka SH, Kerkhoff B, Panarese WC. Design and control of concrete mixtures. Portland cement Association, ASM Handbook Volume 13B, November; 2005. Skokie, IL. 14...

  3. Mechanistic characterization of chloride interferences in electrothermal atomization systems

    USGS Publications Warehouse

    Shekiro, J.M., Jr.; Skogerboe, R.K.; Taylor, H.E.

    1988-01-01

    A computer-controlled spectrometer with a photodiode array detector has been used for wavelength and temperature resolved characterization of the vapor produced by an electrothermal atomizer. The system has been used to study the chloride matrix interference on the atomic absorption spectrometric determination of manganese and copper. The suppression of manganese and copper atom populations by matrix chlorides such as those of calcium and magnesium is due to the gas-phase formation of an analyte chloride species followed by the diffusion of significant fractions of these species from the atom cell prior to completion of the atomization process. The analyte chloride species cannot be formed when matrix chlorides with metal-chloride bond dissociation energies above those of the analyte chlorides are the principal entitles present. The results indicate that multiple wavelength spectrometry used to obtain temperature-resolved spectra is a viable tool in the mechanistic characterization of interference effects observed with electrothermal atomization systems. ?? 1988 American Chemical Society.

  4. Effect of mercuric chloride and methylmercury chloride exposure on tissue concentrations of six essential minerals

    SciTech Connect

    Bogden, J.D.; Kemp, F.W.; Troiano, R.A.; Jortner, B.S.; Timpone, C.; Giuliani, D.

    1980-04-01

    There are few data on the effects of mercury exposure on tissue concentrations of essential minerals. Male Sprague-Dawley rats were exposed to mercuric chloride and methylmercury chloride administered via the drinking water. Subsequently, the kidneys, spleen, liver, and brain were analyzed for mercury, calcium, copper, magnesium, manganese, iron, and zinc by atomic absorption spectrophotometry. Significant differences from controls were found for brain copper, kidney copper, and kidney zinc in the mercuric chloride-exposed animals; and for brain iron, kidney copper, kidney iron, kidney magnesium, spleen magnesium, and liver manganese in the methylmercury chloride-exposed rats. There was a fivefold higher mean kidney copper concentration in the mercuric chloride-exposed group; this may be related to the induction of renal metallothionein synthesis by mercury. Increased kidney copper may be a manifestation of heavy metal-induced renal toxicity. Both inorganic and methylmercury exposure produce significant changes in tissue concentrations of some essential minerals.

  5. Calcium Phosphate Nanoparticles Synthesis Make sure the hood is clean and free of all chemicals other than the ones required.

    E-print Network

    Burgess, Kevin

    Calcium Phosphate Nanoparticles Synthesis Procedure: · Make sure the hood is clean and free of all to dissolve calcium chloride completely). · Likewise prepare 6 x 10-3 M disodium phosphate solution from the above degassed water. · Disodium phosphate is less soluble in water than calcium chloride; please stir

  6. Effects of Calcium Salts on Apple Bitter Rot Caused by Two Colletotrichum spp

    Microsoft Academic Search

    Alan R. Biggs

    1999-01-01

    Biggs, A. R. 1999. Effects of calcium salts on apple b itter rot caused by two Colletotrichum spp. Plant Dis. 83:1001-1005. The effects of three calcium salts on conidial germination, germ tube elongation, growth in vitro, and infectivity in the laboratory and field were studied for the apple bitter rot pat hogens, Colletotrichum gloeosporioides and C. acutatum. Calcium chloride, calcium

  7. Influence of water hardness on the ability of water to rinse bacteria from the skin of processed broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to examine the effect of water hardness on the ability of water to rinse bacteria from the skin of processed broiler chickens. Very hard water (200 ppm total hardness) was prepared by dissolving 0.38 g calcium chloride (CaCl2) and 0.175 g magnesium chloride hexahydrate (Mg...

  8. Effect of water hardness on the ability of water to rinse bacteria from the skin of processed broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of water hardness on the ability of water to rinse bacteria from the skin of processed broiler chickens was examined. Artificial hard water with a total hardness of 200 ppm (very hard water) was prepared by dissolving calcium chloride (CaCl2) and magnesium chloride hexahydrate (MgCl2 •6H2...

  9. Role of water hardness in rinsing bacteria from the skin of processed broiler chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of water hardness on the ability of water to rinse bacteria from the skin of processed broiler chickens was examined. Artificial hard water with a total hardness of 200 ppm (very hard water) was prepared by dissolving calcium chloride (CaCl2) and magnesium chloride hexahydrate (MgCl2 •6H2...

  10. Purification of aqueous plutonium chloride solutions via precipitation and washing.

    SciTech Connect

    Stroud, M. A. (Mary Ann); Salazar, R. R. (Richard R.); Abney, Kent David; Bluhm, E. A. (Elizabeth A.); Danis, J. A. (Janet A.)

    2003-01-01

    Pyrochemical operations at Los Alamos Plutonium Facility (TA-55) use high temperature melt s of calcium chloride for the reduction of plutonium oxide to plutonium metal and hi gh temperature combined melts of sodium chloride and potassium chloride mixtures for the electrorefining purification of plutonium metal . The remaining plutonium and americium are recovered from thes e salts by dissolution in concentrated hydrochloric acid followed by either solvent extraction or io n exchange for isolation and ultimately converted to oxide after precipitation with oxalic acid . Figur e 1 illustrates the current aqueous chloride flow sheet used for plutonium processing at TA-55 .

  11. Development of a new synthesized adsorbent for refrigeration and air conditioning applications

    Microsoft Academic Search

    K. Daou; R. Z. Wang; Z. Z. Xia

    2006-01-01

    This paper presents the results of a study concerned with the impregnation of microporous silica gel, as host matrix, with the calcium chloride, as hygroscopic salt promoter. The concentration of the aqueous solution of calcium used in the preparation of the samples was varied from 0% up to the limit of solubility of CaCl2 in the water. At high humidity,

  12. Copper, aluminum, iron and calcium inhibit human acetylcholinesterase in vitro.

    PubMed

    Pohanka, Miroslav

    2014-01-01

    Acetylcholinesterase (AChE) is an important part of cholinergic nerves where it participates in termination of neurotransmission. AChE can be inhibited by e.g. some Alzheimer disease drugs, nerve agents, and secondary metabolites. In this work, metal salts aluminum chloride, calcium chloride, cupric chloride, ferric chloride, potassium chloride, magnesium chloride and sodium chloride were tested for their ability to inhibit AChE. Standard Ellman assay based on human recombinant AChE was done and inhibition was measured using Dixon plot. No inhibition was proved for sodium, potassium and magnesium ions. However, aluminum, cupric, ferric and calcium ions were able to inhibit AChE via noncompetitive mechanism of inhibition. Though the inhibition is much weaker when compared to e.g. drugs with noncompetitive mechanism of action, biological relevance of the findings can be anticipated. PMID:24473150

  13. Analytical models of calcium binding in a calcium channel

    NASA Astrophysics Data System (ADS)

    Liu, Jinn-Liang; Eisenberg, Bob

    2014-08-01

    The anomalous mole fraction effect of L-type calcium channels is analyzed using a Fermi like distribution with the experimental data of Almers and McCleskey [J. Physiol. 353, 585 (1984)] and the atomic resolution model of Lipkind and Fozzard [Biochemistry 40, 6786 (2001)] of the selectivity filter of the channel. Much of the analysis is algebraic, independent of differential equations. The Fermi distribution is derived from the configuration entropy of ions and water molecules with different sizes, different valences, and interstitial voids between particles. It allows us to calculate potentials and distances (between the binding ion and the oxygen ions of the glutamate side chains) directly from the experimental data using algebraic formulas. The spatial resolution of these results is comparable with those of molecular models, but of course the accuracy is no better than that implied by the experimental data. The glutamate side chains in our model are flexible enough to accommodate different types of binding ions in different bath conditions. The binding curves of Na+ and Ca2+ for [CaCl2] ranging from 10-8 to 10-2 M with a fixed 32 mM background [NaCl] are shown to agree with published Monte Carlo simulations. The Poisson-Fermi differential equation—that includes both steric and correlation effects—is then used to obtain the spatial profiles of energy, concentration, and dielectric coefficient from the solvent region to the filter. The energy profiles of ions are shown to depend sensitively on the steric energy that is not taken into account in the classical rate theory. We improve the rate theory by introducing a steric energy that lumps the effects of excluded volumes of all ions and water molecules and empty spaces between particles created by Lennard-Jones type and electrostatic forces. We show that the energy landscape varies significantly with bath concentrations. The energy landscape is not constant.

  14. Microbial stability and quality of seasoned cracked green Aloreña table olives packed in diverse chloride salt mixtures.

    PubMed

    Bautista-Gallego, J; Arroyo-López, F N; Romero-Gil, V; Rodríguez-Gómez, F; García-García, P; Garrido-Fernández, A

    2013-11-01

    This work was conducted to determine the effect of the partial replacement of NaCl by KCl and CaCl2 (expressed as percentages, wt/vol) on the microbial stability and physicochemical characteristics of seasoned cracked olives using a simplex centroid mixture design. Neither Enterobacteriaceae nor lactic acid bacteria were found during the 50 days that olive packages were monitored. Therefore, microbial instability was considered due to the growth of yeasts, which were the only detected microorganisms; Saccharomyces cerevisiae and Pichia membranifaciens were the most relevant species. Yeasts decreased during the first 21 to 30 days after packing, but their populations rose to 3.5 log CFU/ml by the end of the storage period, clearly causing product deterioration. The partial substitution of NaCl with the other chloride salts slightly altered the phase of microbial inhibition and regrowth. Most of the quality characteristics were not affected by the use of the alternative salt mixtures, but the pH values and Cl(-) concentrations in brine decreased as the CaCl2 concentration increased. Hence, seasoned cracked table olives can be produced using a lower proportion of NaCl without causing significant changes in the shelf life and product quality, although further detailed studies are necessary to guarantee the stability of products packed with specific salt mixtures. PMID:24215697

  15. Determination of metallic iron in a mixture of lime, calcium sulphide and pyrrhotite.

    PubMed

    Sastri, V S

    A method is described for the determination of metallic iron in a complex matrix consisting of calcium oxide, calcium sulphide, carbon and pyrrhotite. The procedure consists of leaching the sample with 5% ammonium chloride solution (10% sucrose solution in some cases) followed by treatment with mercury(II) chloride solution and titration with dichromate solution. PMID:18962353

  16. Investigation of factors influencing chloride extraction efficiency during electrochemical chloride extraction from reinforcing concrete

    NASA Astrophysics Data System (ADS)

    Sharp, Stephen R.

    2005-11-01

    Electrochemical chloride extraction (ECE) is an accelerated bridge restoration method similar to cathodic protection, but operates at higher current densities and utilizes a temporary installation. Both techniques prolong the life of a bridge by reducing the corrosion rate of the reinforcing bar when properly applied. ECE achieves this by moving chlorides away from the reinforcement and out of the concrete while simultaneously increasing the alkalinity of the electrolyte near the reinforcing steel. Despite the proven success, significant use of ECE has not resulted in part due to an incomplete understanding in the following areas: (1) An estimation of the additional service life that can be expected following treatment when the treated member is again subjected to chlorides; (2) The cause of the decrease in current flow and, therefore, chloride removal rate during treatment; (3) Influence of water-to-cement (w/c) ratio and cover depth on the time required for treatment. This dissertation covers the research that is connected to the last two areas listed above. To begin examining these issues, plain carbon steel reinforcing bars (rebar) were embedded in portland cement concrete slabs of varying water-to-cement (w/c) ratios and cover depths, and then exposed to chlorides. A fraction of these slabs had sodium chloride added as an admixture, with all of the slabs subjected to cyclical ponding with a saturated solution of sodium chloride. ECE was then used to remove the chlorides from these slabs while making electrical measurements in the different layers between the rebar (cathode) and the titanium mat (anode) to follow the progress of the ECE process. During this study, it was revealed that the resistance of the outer concrete surface layer increases during ECE, inevitably restricting current flow, while the resistance of the underlying concrete decreases or remains constant. During ECE treatment, a white residue formed on the surface of the concrete. Analyses of the residue revealed that it contains calcium carbonate, calcium chloride, and other yet unidentified minor components when calcium hydroxide was used as the electrolyte. The surface film can be completely removed mechanically or to some extent inhibited chemically, with both of these processes resulting in an increase in the efficiency of the electrochemical chloride extraction process. In addition, an obvious relationship between the cover depth, water-to-cement ratio, and chloride extraction efficiency does not exist, however, cover depth does influence the current density. The final phase of this study will be presented in a VTRC/FHWA final report. This report will include the results that are presented in this dissertation, in addition to the results from the ongoing research. It will also include an estimation of the additional service life that can be expected following treatment.

  17. Nano-porous calcium phosphate balls.

    PubMed

    Kovach, Ildyko; Kosmella, Sabine; Prietzel, Claudia; Bagdahn, Christian; Koetz, Joachim

    2015-08-01

    By dropping a NaH2PO4·H2O precursor solution to a CaCl2 solution at 90°C under continuous stirring in presence of two biopolymers, i.e. gelatin (G) and chitosan (C), supramolecular calcium phosphate (CP) card house structures are formed. Light microscopic investigations in combination with scanning electron microscopy show that the GC-based flower-like structure is constructed from very thin CP platelets. Titration experiments indicate that H-bonding between both biopolymers is responsible for the synergistic effect in presence of both polymers. Gelatin-chitosan-water complexes play an important role with regard to supramolecular ordering. FTIR spectra in combination with powder X-ray diffraction show that after burning off all organic components (heating up >600°C) dicalcium and tricalcium phosphate crystallites are formed. From high resolution transmission electron microscopy (HR-TEM) it is obvious to conclude, that individual crystal platelets are dicalcium phosphates, which build up ball-like supramolecular structures. The results reveal that the GC guided crystal growth leads to nano-porous supramolecular structures, potentially attractive candidates for bone repair. PMID:26052107

  18. Interactions between chloride and sulfate or silica removals from wastewater using an advanced lime-aluminum softening process: equilibrium modeling.

    PubMed

    Abdel-Wahab, Ahmed; Batchelor, Bill

    2007-05-01

    Interactions among chloride, sulfate, and silica removals from recycled industrial wastewater using an ultra-high lime with aluminum process (UHLA) were studied. An equilibrium model that is able to accurately predict the chemical behavior and interactions between chloride and sulfate or silica with UHLA at various initial conditions and chemical reagents was developed. X-ray diffraction (XRD) analysis was conducted to identify the precipitated solids formed in the UHLA process. Model predictions indicated that simultaneous removal of sulfate and chloride can be best described by the formation of a solid solution containing calcium chloroaluminate, calcium sulfoaluminate (ettringite), calcium monosulfate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. However, simultaneous removal of silica and chloride can be best described by precipitation of calcium silicate and calcium aluminosilicate in addition to a solid solution containing calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. The XRD results indicated the presence of the same solids assumed by the equilibrium model. PMID:17571843

  19. The binding of chloride ions by sulphate resistant portland cement

    Microsoft Academic Search

    A. K. Suryavanshi; J. D. Scantlebury; S. B. Lyon

    1995-01-01

    The relative tendency of different portland cements to remove chloride ions from the mix water by forming chloro-complexes is an important factor in the study of the corrosion of the embedded steel. The tri-calcium aluminate (C3A) phase of the ordinary portland cement (OPC) plays a dominant role in binding the chloride ions, but little quantitative information is available in the

  20. Mutations in the putative calcium-binding domain of polyomavirus VP1 affect capsid assembly

    NASA Technical Reports Server (NTRS)

    Haynes, J. I. 2nd; Chang, D.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Calcium ions appear to play a major role in maintaining the structural integrity of the polyomavirus and are likely involved in the processes of viral uncoating and assembly. Previous studies demonstrated that a VP1 fragment extending from Pro-232 to Asp-364 has calcium-binding capabilities. This fragment contains an amino acid stretch from Asp-266 to Glu-277 which is quite similar in sequence to the amino acids that make up the calcium-binding EF hand structures found in many proteins. To assess the contribution of this domain to polyomavirus structural integrity, the effects of mutations in this region were examined by transfecting mutated viral DNA into susceptible cells. Immunofluorescence studies indicated that although viral protein synthesis occurred normally, infective viral progeny were not produced in cells transfected with polyomavirus genomes encoding either a VP1 molecule lacking amino acids Thr-262 through Gly-276 or a VP1 molecule containing a mutation of Asp-266 to Ala. VP1 molecules containing the deletion mutation were unable to bind 45Ca in an in vitro assay. Upon expression in Escherichia coli and purification by immunoaffinity chromatography, wild-type VP1 was isolated as pentameric, capsomere-like structures which could be induced to form capsid-like structures upon addition of CaCl2, consistent with previous studies. However, although VP1 containing the point mutation was isolated as pentamers which were indistinguishable from wild-type VP1 pentamers, addition of CaCl2 did not result in their assembly into capsid-like structures. Immunogold labeling and electron microscopy studies of transfected mammalian cells provided in vivo evidence that a mutation in this region affects the process of viral assembly.

  1. Calcium-induced proline accumulation contributes to amelioration of NaCl injury and expression of glutamine synthetase in greater duckweed (Spirodela polyrhiza L.).

    PubMed

    Cheng, Tai-Sheng; Hung, Meng-Ju; Cheng, Yen-I; Cheng, Lee-Ju

    2013-11-15

    The calcium-mediated proline accumulation is a critical response under NaCl stress and the function of the induced proline as a glutamine synthetase (GS) protectant in greater duckweed was investigated. The plants were treated with solutions containing 100mM NaCl, 200 mM NaCl, 200 mM NaCl plus 10mM CaCl2, or 10mM CaCl2 alone for 4 days. At the end of the experiment, the fronds of inoculum treated with 200 mM NaCl showed the chlorotic effect, higher glutamate dehydrogenase (NADH-GDH) activity and lower GS activity. At the lower salinity, the activities of GS and NADH-GDH were not altered markedly. A significant accumulation of proline was not found under either low or high salinity. The activity of ?(1)-pyrroline-5-carboxylate reductase (P5CR) was enhanced only at 200 mM NaCl but remained unchanged at 100mM NaCl. The activity of ?(1)-pyrroline-5-carboxylate synthetase (P5CS) did not change under salinity-stressed. Addition of CaCl2 to the salt stressed plants not only lowered NaCl injury but also showed an elevated level of proline contents in response to the salinity treatment. In addition, both GS activity and corresponding polypeptides were expressed close to the level of control. Exogenous proline protects GS2 and the 32 kDa protein in photosystem II reaction center (D1) from H2O2-induced redox degradation in the chloroplast lysates of duckweed. The results suggest that calcium-induced proline accumulation may play an important role as a GS protectant under NaCl exposure in S. polyrhiza. PMID:24200992

  2. Evaluation of microbeads of calcium alginate as a fluidized bed medium for affinity chromatography of Aspergillus niger Pectinase.

    PubMed

    Roy, Ipsita; Jain, Sulakshana; Teotia, Sunita; Gupta, Munishwar Nath

    2004-01-01

    Calcium alginate microbeads (212-425 microm) were prepared by spraying 2% (w/v) alginate solution into 1 M CaCl2 solution. The fluidization behavior of these beads was studied, and the bed expansion index and terminal velocity were found to be 4.3 and 1808 cm h(-1), respectively. Residence time distribution curves showed that the dispersion of the protein was much less with these microbeads than with conventionally prepared calcium alginate macrobeads when both kinds of beads were used for chromatography in a fluidized bed format. The fluidized bed of these beads was used for the purification of pectinase from a commercial preparation. The media performed well even with diluted feedstock; 90% activity recovery with 211-fold purification was observed. PMID:15458334

  3. pH-dependent release property of alginate beads containing calcium carbonate particles.

    PubMed

    Han, M R; Kwon, M C; Lee, H Y; Kim, J C; Kim, J D; Yoo, S K; Sin, I S; Kim, S M

    2007-12-01

    Alginate bead containing calcium carbonate particle were prepared by dropping the suspension of alginate/calcium carbonate (4/1, w/w) into aqueous solution of CaCl(2) (0.1 M). The pH-dependent release property of the bead was observed for 12 h using blue dextran as a model drug. The release increased up to 4 h in a saturation manner. When no calcium carbonate was contained, the release exhibited no marked variation with pH and the values were 27-39%. On the other hand, in case calcium carbonate was included in the matrix of alginate beads, intensive release(40-50%) was achieved in acidic and neutral conditions and the degrees of release were suppressed in alkali conditions and the values were approximately 20%. The pH-sensitive release property is possibly because the particles of calcium carbonate embedded in the matrix of beads were leached out in acidic and neutral conditions, leaving cavities in the matrix. The cavities are likely to be main pathways for the release of blue dextran. PMID:17926170

  4. Chloride channels in stroke

    PubMed Central

    Zhang, Ya-ping; Zhang, Hao; Duan, Dayue Darrel

    2013-01-01

    Vascular remodeling of cerebral arterioles, including proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs), is the major cause of changes in the cross-sectional area and diameter of the arteries and sudden interruption of blood flow or hemorrhage in the brain, ie, stroke. Accumulating evidence strongly supports an important role for chloride (Cl?) channels in vascular remodeling and stroke. At least three Cl? channel genes are expressed in VSMCs: 1) the TMEM16A (or Ano1), which may encode the calcium-activated Cl? channels (CACCs); 2) the CLC-3 Cl? channel and Cl?/H+ antiporter, which is closely related to the volume-regulated Cl? channels (VRCCs); and 3) the cystic fibrosis transmembrane conductance regulator (CFTR), which encodes the PKA- and PKC-activated Cl? channels. Activation of the CACCs by agonist-induced increase in intracellular Ca2+ causes membrane depolarization, vasoconstriction, and inhibition of VSMC proliferation. Activation of VRCCs by cell volume increase or membrane stretch promotes the production of reactive oxygen species, induces proliferation and inhibits apoptosis of VSMCs. Activation of CFTR inhibits oxidative stress and may prevent the development of hypertension. In addition, Cl? current mediated by gamma-aminobutyric acid (GABA) receptor has also been implicated a role in ischemic neuron death. This review focuses on the functional roles of Cl? channels in the development of stroke and provides a perspective on the future directions for research and the potential to develop Cl? channels as new targets for the prevention and treatment of stroke. PMID:23103617

  5. Deactivation of metal chlorides by alkaline compounds inhibits formation of chlorinated aromatics.

    PubMed

    Fujimori, Takashi; Fujinaga, Yasuka; Takaoka, Masaki

    2010-10-01

    The inhibitory mechanisms of alkaline compounds on the formation of chlorinated aromatic (aromatic-Cl) compounds in postcombustion fly ash from thermal processes such as municipal solid waste (MSW) incineration are not fully understood. Here, we report quantitative and X-ray spectroscopic evidence that deactivation of metal chloride promoter activity by alkaline compounds inhibits the formation of aromatic-Cl compounds. The formation of aromatic-Cl compounds such as chlorobenzenes and polychlorinated biphenyls in real MSW fly ash was inhibited by the addition of NaOH, Ca(OH)(2), or NaHCO(3), either dry or in solution, with the fly ash. With optimal conditions, the formation of aromatic-Cl compounds was inhibited by more than 95% in comparison with formation in reheated raw MSW fly ash. We prepared simplified model fly ash samples to estimate the influence of alkaline compounds on trace Cu, Fe, Pb, and Zn chlorides, which strongly promote aromatic-Cl compound formation. More than 99% inhibition was observed in some model samples. Cl K-edge X-ray absorption and X-ray diffraction provided clear evidence of promoter deactivation, as NaOH or NaHCO(3) changed to NaCl, and Ca(OH)(2) changed to CaCl(2) or CaClOH by reaction with the metal chlorides. NaOH was the most reactive and useful of the three alkaline compounds tested. We recommend deactivation of metal chlorides as an environmentally friendly method of inhibiting the formation of aromatic-Cl compounds, with the added benefit of changing the alkaline compounds and metal chlorides into harmless chemicals such as NaCl and metal oxides. PMID:20839860

  6. Calcium and sodium bentonite for hydraulic containment applications

    Microsoft Academic Search

    Mark H. Gleason; David E. Daniel; Gerald R. Eykholt

    1997-01-01

    The hydraulic conductivity of calcium and sodium bentonites was investigated for sand-bentonite mixtures, a thin bentonite layer simulating a geosynthetic clay liner (GCL), and bentonite-cement mixtures simulating backfill for a vertical cutoff wall. The permeant liquids were tap water and distilled water containing 0.25 M calcium chloride. In general, the hydraulic performance of calcium bentonite was not significantly better than

  7. Voltage and time-dependent chloride currents in chick skeletal muscle cells grown in tissue culture

    Microsoft Academic Search

    Joy A. Steele

    1989-01-01

    Membrane chloride currents in chick skeletal muscle cells grown in tissue culture were studied by use of the whole cell variation of the patch electrode voltage clamp technique. Small diameter myoballs were obtained by adding colchicine to the growth media. To isolate the currents through the chloride channels, the currents through the sodium, calcium and potassium channels were minimized. With

  8. AFREM test procedures concerning chlorides in concrete: Extraction and titration methods

    Microsoft Academic Search

    T. Chaussadent; G. Arliguie

    1999-01-01

    The article presents a part of a study carried out by the AFREM “Durability-Chloride penetration in concrete” group. It deals\\u000a with the extraction of “free” and total chlorides from concrete and their titration. The goal is to define test procedures\\u000a that will take into account the chemical behaviour of concrete components, in particular bound chlorides in calcium chloroaluminate.\\u000a The basic

  9. Bioinspired synthesis of fluorescent calcium carbonate/carbon dot hybrid composites.

    PubMed

    Guo, Shanshan; Yang, Miao; Chen, Min; Zhang, Juan; Liu, Kang; Ye, Ling; Gu, Wei

    2015-04-21

    Herein, we report a novel method to synthesise fluorescent calcium carbonate/carbon dots (CaCO3/CDs) by simply mixing CaCl2 and Na2CO3 solutions in the presence of CDs. There are two roles of CDs in this easy and cost-effective biomimetic strategy, that is as the template to direct the formation and assembly of calcite nanocrystals into hierarchical spheres with diameters in the range of 200-300 nm and simultaneously as the phosphor to enable the CaCO3 to emit blue fluorescence under UV (365 nm) irradiation with a quantum yield of 56.2%. The CaCO3/CD hybrid composites possessing unique fluorescence properties are potentially useful in various applications. PMID:25845422

  10. A Proposed Mechanism for the Thermal Denaturation of a Recombinant Bacillus Halmapalus Alpha-amylase - the Effect of Calcium Ions

    NASA Technical Reports Server (NTRS)

    Nielsen, Anders D.; Pusey, Marc L.; Fuglsang, Claus C.; Westh, Peter

    2003-01-01

    The thermal stability of a recombinant alpha-amylase from Bacillus halmapalus alpha-amylase (BHA) has been investigated using circular dichroism spectroscopy (CD) and differential scanning calorimetry (DSC). This alpha-amylase is homologous to other Bacillus alpha-amylases where previous crystallographic studies have identified the existence of 3 calcium binding sites in the structure. Denaturation of BHA is irreversible with a Tm of approximately 89 C, and DSC thermograms can be described using a one-step irreversible model. A 5 C increase in T(sub m) in the presence of 10 fold excess CaCl2 was observed. However, a concomitant increase in the tendency to aggregate was also observed. The presence of 30-40 fold excess calcium chelator (EDTA or EGTA) results in a large destabilization of BHA corresponding to about 40 C lower T(sub m), as determined by both CD and DSC. Ten fold excess EGTA reveals complex DSC thermograms corresponding to both reversible and irreversible transitions, which possibly originate from different populations of BHA:calcium complexes. The observations in the present study have, in combination with structural information of homologous alpha-amylases, provided the basis for the proposal of a simple denaturation mechanism of BHA. The proposed mechanism describes the irreversible thermal denaturation of different BHA:calcium complexes and the calcium binding equilibrium involved. Furthermore, the model accounts for a temperature induced reversible structural change associated with calcium binding.

  11. Advances in lithium and calcium high-rate oxyhalide batteries

    NASA Astrophysics Data System (ADS)

    Hagan, W. P.; Green, S.; Sargeant, D. G.; Packer, R. K.

    The characteristics of lithium and calcium oxyhalide battery systems are considered, with special attention given to those of lithium-thionyl chloride and lithium-sulfuryl chloride cells. It is shown that, for a capability of above 50 mA/sq cm, lithium-sulfuryl chloride is the preferred cell chemistry, although calcium-thionyl chloride (which is acceptable up to 50 mA/sq cm) may be preferrable if thermal management is a problem. Lithium-sulfuryl chloride cells were found to exhibit a form of concentration polarization which is strongly dependent on interelectrode separation. In such cells, interelectrode separations have to be minimized if premature failure is to be avoided.

  12. Calcium - urine

    MedlinePLUS

    ... much calcium Too much production of parathyroid hormone (PTH) by the parathyroid glands in the neck (hyperparathyroidism) ... glands in the neck do not produce enough PTH (hypoparathyroidism) Use of a water pill called a ...

  13. Calcium-Binding Properties and ATPase Activities of Rat Liver Plasma Membranes

    PubMed Central

    Chambaut, Anne-Marie; Leray-Pecker, Françoise; Feldmann, Gérard; Hanoune, Jacques

    1974-01-01

    Plasma membranes from rat liver purified according to the procedure of Neville bind calcium ions by a concentration-dependent, saturable process with at least two classes of binding sites. The higher affinity sites bind 45 nmol calcium/mg membrane protein with a KD of 3 µM. Adrenalectomy increases the number of the higher affinity sites and the corresponding KD. Plasma membranes exhibit a (Na+-K+)-independent-Mg2+-ATPase activity which is not activated by calcium between 0.1 µM and 10 mM CaCl2. Calcium can, with less efficiency, substitute for magnesium as a cofactor for the (Na+-K+)-independent ATPase. Both Mg2+- and Ca2+-ATPase activities are identical with respect to pH dependence, nucleotide specificity and sensitivity to inhibitors. But when calcium is substituted for magnesium, there is no detectable membrane phosphorylation from [?-32P] ATP as it is found in the presence of magnesium. The existence of high affinity binding sites for calcium in liver plasma membranes is compatible with a regulatory role of this ion in membrane enzymic mechanisms or in hormone actions. Plasma membranes obtained by the procedure of Neville are devoid of any Ca2+-activated-Mg2+-ATPase activity indicating the absence of the classical energy-dependent calcium ion transport. These results would suggest that the overall calcium-extruding activity of the liver cell is mediated by a mechanism involving no direct ATP hydrolysis at the membrane level. PMID:4276192

  14. 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

  15. 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 today’s 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

  16. Orthokinetic flocculation of caseinate-stabilized emulsions: influence of calcium concentration, shear rate, and protein content.

    PubMed

    Schokker, E P; Dalgleish, D G

    2000-02-01

    Calcium-induced flocculation of caseinate-stabilized soybean oil-in-water emulsions in conditions of Couette flow was studied. A concentrated emulsion (20% oil, 0.5-2.0% sodium caseinate in 20 mM imidazole, pH 7) was diluted 20 times in buffer containing concentrations of CaCl(2) between 9 and 17 mM and sheared at rates between 335 and 1340 s(-)(1). The average particle size (d(43)), measured by integrated light scattering, increased in a sigmoidal manner with shearing time. An increased shear rate resulted in an increased flocculation rate, because of the increased number of collisions between particles, but a decreased value of the maximum d(43), because higher shear rates increasingly disrupted the flocs. The flocculation rate was increased by increasing the calcium concentration, indicating an increased collision efficiency. The orthokinetic stability of the emulsions was increased with increased protein content, and it is postulated that the increased surface coverage and hydrodynamic thickness of the adsorbed protein layer increased steric repulsion between droplets, so that higher calcium concentrations were necessary to induce sufficient conformational change of the proteins to allow flocculation. At high caseinate concentrations, calcium may also induce precipitation of unadsorbed caseins from the serum to the oil-water interface, thereby increasing steric repulsion and hence increasing orthokinetic stability. PMID:10691616

  17. 5-Hydroxytryptamine-induced calcium-channel gating in rainbow trout (Oncorhynchus mykiss) peripheral blood lymphocytes.

    PubMed Central

    Ferriere, F; Khan, N A; Meyniel, J P; Deschaux, P

    1997-01-01

    The present study was conducted on peripheral blood lympho-cytes of rainbow trout (Oncorhynchus mykiss) to assess the role of 5-hydroxytryptamine (5-HT; 'serotonin') in calcium signalling. 5-HT-induced increases in intracellular free calcium concentrations, [Ca2+]i, and its action was mediated by 5-HT receptor subtype 3 (5-HT3), but not by 5-HT receptor subtype 1A (5-HT1A) or subtype 2 (5-HT2) in these cells. In Ca2+-containing medium (1 mM CaCl2), 5-HT and 2-methyl-5-HT (5-HT3 receptor agonist) induced increases in [Ca2+]i, whereas in Ca2+-free medium (0 Ca2+, 1 mM EGTA), these two agents failed to evoke increases in [Ca2+]i in these cells, demonstrating that 5-HT mobilizes Ca2+ from the extracellular environment. Furthermore, 5-HT-induced increases in [Ca2+]i are not contributed to by the intracellular endoplasmic reticulum (ER) pool, as thapsigargin, an agent that recruits Ca2+ from ER stores, had additive effects on 5-HT-induced [Ca2+]i responses in fish peripheral lymphocytes. 5-HT-induced increases in [Ca2+]i were mediated by 5-HT3 receptors via gating the calcium through L-type, but not N-type, calcium channels in trout lymphocytes. PMID:9173890

  18. Purification and characterisation of a glutamic acid-containing peptide with calcium-binding capacity from whey protein hydrolysate.

    PubMed

    Huang, Shun-Li; Zhao, Li-Na; Cai, Xixi; Wang, Shao-Yun; Huang, Yi-Fan; Hong, Jing; Rao, Ping-Fan

    2015-02-01

    The bioavailability of dietary ionised calcium is affected by intestinal basic environment. Calcium-binding peptides can form complexes with calcium to improve its absorption and bioavailability. The aim of this study was focused on isolation and characterisation of a calcium-binding peptide from whey protein hydrolysates. Whey protein was hydrolysed using Flavourzyme and Protamex with substrate to enzyme ratio of 25:1 (w/w) at 49 °C for 7 h. The calcium-binding peptide was isolated by DEAE anion-exchange chromatography, Sephadex G-25 gel filtration and reversed phase high-performance liquid chromatography (RP-HPLC). A purified peptide of molecular mass 204 Da with strong calcium binding ability was identified on chromatography/electrospray ionisation (LC/ESI) tandem mass spectrum to be Glu-Gly (EG) after analysis and alignment in database. The calcium binding capacity of EG reached 67·81 ?g/mg, and the amount increased by 95% compared with whey protein hydrolysate complex. The UV and infrared spectrometer analysis demonstrated that the principal sites of calcium-binding corresponded to the carboxyl groups and carbonyl groups of glutamic acid. In addition, the amino group and peptide amino are also the related groups in the interaction between EG and calcium ion. Meanwhile, the sequestered calcium percentage experiment has proved that EG-Ca is significantly more stable than CaCl2 in human gastrointestinal tract in vitro. The findings suggest that the purified dipeptide has the potential to be used as ion-binding ingredient in dietary supplements. PMID:25592629

  19. Phosphonium chloride for thermal storage

    NASA Technical Reports Server (NTRS)

    Sutton, J. G.; Heimlich, P. F.; Tepper, E. H.

    1972-01-01

    Development of systems for storage of thermal energy is discussed. Application of phosphonium chloride for heat storage through reversible dissociation is described. Chemical, physical, and thermodynamic properties of phosphonium chloride are analyzed and dangers in using phosphonium chloride are explained.

  20. Meteoric calcium

    NASA Astrophysics Data System (ADS)

    Plane, John M. C.

    2011-11-01

    Calcium is found throughout the solar system, the Earth's crust and oceans, and is an essential constituent of cells, shells and bones -- yet it is curiously scarce in the upper atmosphere. John Plane ponders on this 25-year-old mystery.

  1. 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.

  2. The effect of chloride ion concentration gradients on the initiation of localized corrosion of steel in reinforced concrete

    SciTech Connect

    Kane, M.J.; Brown, R. [Univ. of Rhode Island, Kingston, RI (United States). Dept. of Chemical Engineering

    1994-12-31

    It has been established that for steel reinforced concrete roads treated with deicing salts or exposed to a marine environment, chloride ions are introduced at the surface of the concrete structure. Two models were discussed in which chloride ion concentration gradients would form in a steel reinforced concrete structure. Electrochemical testing to investigate the models was conducted on plain carbon steel specimens in a simulated concrete environment of saturated calcium hydroxide solution with varying concentrations of sodium chloride. The varying chloride ion concentrations promoted open circuit potential shifts. These potential shifts may lead to galvanic corrosion effects depending on the chloride ion concentration gradients in the structure.

  3. Original article Availability of calcium from skim milk, calcium sulfate

    E-print Network

    Paris-Sud XI, Université de

    Original article Availability of calcium from skim milk, calcium sulfate and calcium carbonate; accepted 19 November 1999) Abstract --Dairy products provide abundant, accessible calcium for humans, while some calcium sulfate-rich mineral waters could provide appreciable amounts of calcium

  4. Purification and characterization of two isozymes of polygalacturonase from Botrytis cinerea. Effect of calcium ions on polygalacturonase activity.

    PubMed

    Cabanne, Charlotte; Donèche, Bernard

    2002-01-01

    The phytopathogenic fungus Botrytis cinerea produces a set of polygalacturonases (PGs) which are involved in the enzymatic degradation of pectin during plant tissue infection. Two polygalacturonases secreted by B. cinerea in seven-day-old liquid culture were purified to apparent homogeneity by chromatography. PG I was an exopolygalacturonase of molecular weight 65 kDa and pI 8.0 and PG II was an endopolygalacturonase of 52 kDa and pI 7.8. Enzymatic activity of PG I and PG II was partially inhibited by 1 mM CaCl2, probably by calcium chelation of polygalacturonic acid, the substrate of the enzyme. PMID:12398287

  5. Apatite-forming ability of Ti-15Zr-4Nb-4Ta alloy induced by calcium solution treatment.

    PubMed

    Yamaguchi, Seiji; Takadama, Hiroaki; Matsushita, Tomiharu; Nakamura, Takashi; Kokubo, Tadashi

    2010-02-01

    Ti-15Zr-4Nb-4Ta alloy free from cytotoxic elements shows high mechanical strength and high corrosion resistance. However, simple NaOH and heat treatments cannot induce its ability to form apatite in the body environment. In the present study, this alloy was found to exhibit high apatite-forming ability when it was treated with NaOH and CaCl(2) solutions, and then subjected to heat and hot water treatments to form calcium titanate, rutile, and anatase on its surface. Its high apatite-forming ability was maintained even in 95% relative humidity at 80 degrees C after 1 week. The surface layer of the treated alloy had scratch resistance high enough for handling hard surgical devices. Thus, the treated alloy is believed to be useful for orthopedic and dental implants. PMID:19842018

  6. Effect of Varying Dietary Ratio of Sodium and Chloride on the Responses of Lactating Dairy Cows in Hot Weather

    Microsoft Academic Search

    C. E. Coppock; P. A. Grant; S. J. Portzer; Adrian Escobosa; T. E. Wehrly

    1982-01-01

    Twenty-four lactating Holstein and Jersey cows were fed concentrate mixtures formulated to supplement total diets with 1) no added sodium chloride, 2) 1.0% sodium chloride, 3) 1.14% calcium chloride, and 4) 1.45% sodium bicarbonate during a 9-wk continuous trial, Experi- ment 1. Responses measured were body temperature, respiration rate, milk yield, milk composition, and 15 blood variables to evaluate acid-base

  7. Determination of cytoplasmic calcium concentration in Dryopteris spores: a developmentally non-disruptive technique for loading of the calcium indicator fura-2

    NASA Technical Reports Server (NTRS)

    Scheuerlein, R.; Schmidt, K.; Poenie, M.; Roux, S. J.

    1991-01-01

    Germination of Dryopteris spores is mediated by the physiologically active, far-red-absorbing form of phytochrome, Pfr, and external Ca2+ is necessary for the transduction of the light signal. Because knowledge about the cytoplasmic calcium ion concentration, [Ca2+]i, is of great importance for understanding the role of calcium during signal transduction, this value was measured using fura-2 in fern spores undergoing the normal developmental progression into germination. Fura-2 was loaded into the spores by electroporation, which does not disrupt the normal process of germination. The intensity of the fluorescence emission of the loaded fura-2 was analysed by a microspectrophotometric assay of single spores, and successful loading could be obtained by the application of ten electrical pulses (field strength 7.5 kV cm-1, half-life (time constant) 230 microseconds). Fura-2 was alternately excited by light of wavelengths 355 and 385 nm through an inverted fluorescence microscope, and the emitted fura-2 fluorescence was collected by a silicon-intensified video camera. The cytoplasmic calcium ion concentration was calculated from the ratio of the camera output obtained for both wavelengths and displayed by a pseudo-color technique. Spores responded to changes of the extracellular Ca2+ concentration, and this observation is considered as evidence that fura-2 is loaded into the cytoplasm. The substitution of a low external [Ca2+] (1 mM ethyleneglycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA)) by 1 mM CaCl2 caused a fast increase of [Ca2+]i from approx. 50 nM to above 500 nM. In contrast, the subsequent substitution of CaCl2 by EGTA decreased [Ca2+]i again below 100 nM within 0.5 h. Furthermore, the application of ionomycin could initiate a change in [Ca2+]i according to the Ca2+ gradient established between the extracellular medium and cytoplasm. In spores sown on a Ca(2+) -free medium, [Ca2+]i, analysed in a buffer containing EGTA, was found to be around 50 nM during the first days of cultivation, independent of the irradiation protocol. However, if spores were grown in darkness on a Ca(2+) -containing medium and analysed in EGTA, [Ca2+]i was significantly higher (> or = 500 nM). In red-light-irradiated spores, [Ca2+]i was found to decrease with increasing time after irradiation, and was determined to be less than 100 nM when analysis was done 44 h after germination was initiated by the light treatment.

  8. Migration of Calcium and Its Role in the Regulation of Seismonasty in the Motor Cell of Mimosa pudica L. 1

    PubMed Central

    Toriyama, H.; Jaffe, M. J.

    1972-01-01

    Volume and conformational changes of the contractile tannin vacuoles of the abaxial motor cells of the primary pulvinus of Mimosa pudica L. parallel the seismonastic leaf movement. Since such changes in cells and organelles of animal systems are often regulated by calcium, we studied Ca2+ movement in the motor cells and tissue. By fixation with Lillie's neutral buffered formalin, followed by staining with alizarin red sulfate (ARS), calcium was localized in the tannin vacuoles of the motor cells of the primary pulvinus. After treatment with ethylenediaminetetraacetate, 8-hydroxyquinoline, and several other calcium-complexing or extracting agents, the color reaction due to alizarin red sulfonate was no longer present. By using an analytical method, it was shown that the effluent from stimulated pulvini has significantly more Ca2+ than that from unstimulated controls. Ten millimolar LaCl3 inhibits recovery of the tannin vacuole in vivo in 10 mm CaCl2 or in distilled water. Quantitative data obtained by microspectrophotometry demonstrated calcium migration during the bending movement of the primary pulvinus. In the adaxial motor cells a small amount of calcium migrates from the tannin vacuole, and calcium on the cell wall moves to the central vacuole. In the abaxial half, a large amount of calcium from the tannin vacuole moves to the central vacuole of the motor cell. It is probable that the calcium binds to the microfibrillar contents of the central vacuole. These observations support the contention that Ca2+ migrates between the surface of the tannin vacuole and the inside of the central vacuole. The recovery and maintenance of the tannin vacuole in the spherical form may play a role in maintaining turgor in the motor cells of the abaxial half of the primary pulvinus of Mimosa. Images PMID:16657899

  9. Impacts of calcium addition and different oil types and levels on in vitro rumen fermentation and digestibility.

    PubMed

    Gül?en, Nurettin; Umucalilar, Huzur Derya; Inal, Fatma; Hayirli, Armagan

    2006-12-01

    This in vitro study was designed to investigate the effects of calcium addition to substrates differing in source and level of oil on fermentation, gas production, and digestibility parameters. Substrates were made from basal mixtures containing three levels of calcium salt (0, 1, and 2% CaCl2) to contain three levels (3, 6, and 9%) of two types (sunflower and soy) of oil. After collecting from two Holstein bulls and mixing with buffer, rumen fluid was used to incubate the resulting 18 mixtures in duplicate. Ionizable calcium, pH and NH3-N concentration were measured during incubation. Gas production was measured at 6, 12, 24, and 48 h after incubation. Kinetics parameters of gas production and in vitro dry matter digestibility (IVDMD) were calculated from regression coefficients of an exponential equation and a linear equation, respectively. Data were analysed using 3-way ANOVA with repeated measure option in which the parameter time was a subplot. Oil type did not affect pH and ionizable calcium concentration. There were linear increases and decreases in pH and ionizable calcium concentration in response to increasing oil and calcium levels, respectively. However, with increasing oil levels there were no interactions between calcium addition and oil level on pH and ionizable calcium concentration. None of the treatments affected NH3-N concentration. The amount of gas produced from substrates containing sunflower oil was greater than soy oil (41.7 vs. 40.5 ml). Cumulative gas production and amount of gas production from insoluble but slowly fermentable portion of the supplemental mixtures linearly decreased and linearly increased as oil and calcium levels increased in the substrates, respectively. However, interactions of calcium addition and oil level on gas production and kinetics of gas production were lacking. Oil type did not affect IVDMD. Despite lacking main effects, interaction of calcium addition and oil level indicated that increasing calcium level alleviated depression in IVDMD resulting from increasing oil level. In conclusion, increasing oil level depressed, whereas calcium addition stimulated ruminal fermentation. Improvement in IVDMD may partially support that calcium addition alleviates the adverse effects of oil and that more calcium is needed when diets are supplemented with increasing amounts of oil. PMID:17236704

  10. Effects of calcium, alginate, and calcium-alginate immobilization on growth and tropane alkaloid levels of a stable suspension cell line of Datura innoxia Mill

    Microsoft Academic Search

    E. Gontier; B. S. Sangwan; J. N. Barbotin

    1994-01-01

    Summary  A stabilized two-year old suspension of a Datura innoxia cell line, producing small amounts of tropane alkaloids (scopolamine and hyoscyamine) was used in this study. Calcium alginate immobilization has been shown to be able to increase secondary metabolite (i. e. alkaloid) production. The effects of calcium and ungellified alginate were both beneficial for tropane alkaloid synthesis; a 10mM calcium chloride

  11. Calcium Causes a Conformational Change in Lamin A Tail Domain that Promotes Farnesyl-Mediated Membrane Association

    PubMed Central

    Kalinowski, Agnieszka; Qin, Zhao; Coffey, Kelli; Kodali, Ravi; Buehler, Markus J.; Lösche, Mathias; Dahl, Kris Noel

    2013-01-01

    Lamin proteins contribute to nuclear structure and function, primarily at the inner nuclear membrane. The posttranslational processing pathway of lamin A includes farnesylation of the C-terminus, likely to increase membrane association, and subsequent proteolytic cleavage of the C-terminus. Hutchinson Gilford progeria syndrome is a premature aging disorder wherein a mutant version of lamin A, ?50 lamin A, retains its farnesylation. We report here that membrane association of farnesylated ?50 lamin A tail domains requires calcium. Experimental evidence and molecular dynamics simulations collectively suggest that the farnesyl group is sequestered within a hydrophobic region in the tail domain in the absence of calcium. Calcium binds to the tail domain with an affinity KD ? 250 ?M where it alters the structure of the Ig-fold and increases the solvent accessibility of the C-terminus. In 2 mM CaCl2, the affinity of the farnesylated protein to a synthetic membrane is KD ? 2 ?M, as measured with surface plasmon resonance, but showed a combination of aggregation and binding. Membrane binding in the absence of calcium could not be detected. We suggest that a conformational change induced in ?50 lamin A with divalent cations plays a regulatory role in the posttranslational processing of lamin A, which may be important in disease pathogenesis. PMID:23708364

  12. 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 ...

  13. Effects of calcium-chelating agents and pasteurisation on certain properties of calcium-fortified soy milk

    Microsoft Academic Search

    Pattavara Pathomrungsiyounggul; Michael J. Lewis; Alistair S. Grandison

    2010-01-01

    Addition of 25mM calcium chloride to soy milk reduced pH, increased ionic calcium and caused it to coagulate. The effects of different chelating agents were investigated on selected physicochemical properties of soy milk and on preventing coagulation. The soy milks were then pasteurised to examine how heat treatment changed some of these properties as well as to evaluate their effects

  14. Propagation and Retention of Viscoelastic Surfactants in Carbonate Cores 

    E-print Network

    Yu, Meng

    2012-07-16

    , including polymers and viscoelastic surfactants. Acid-soluble polymers (Pabley et al. 1982; Crowe et al. 1989) or crosslinked polymers (Metcalf et al. 2000) have been used to increase the viscosity and to improve the performance of HCl, in which... of hydrochloric acid is a result of its cost- effectiveness and soluble reaction products with carbonate rocks (calcium chloride, CaCl2, and magnesium chloride, MgCl2). However, hydrochloric acid is relatively corrosive on wellbore tubular and pumps, especially...

  15. Chloride removal from vitrification offgas

    SciTech Connect

    Slaathaug, E.J. [Westinghouse Hanford Co., Richland, WA (United States)

    1995-06-01

    This study identified and investigated techniques of selectively purging chlorides from the low-level waste (LLW) vitrification process with the purge stream acceptable for burial on the Hanford Site. Chlorides will be present in high concentration in several individual feeds to the LLW Vitrification Plant. The chlorides are highly volatile in combustion type melters and are readily absorbed by wet scrubbing of the melter offgas. The Tank Waste Remediation System (TWRS) process flow sheets show that the resulting chloride rich scrub solution is recycled back to the melter. The chlorides must be purged from the recycle loop to prevent the buildup of excessively high chloride concentrations.

  16. Chloride chemical form in various types of fly ash

    SciTech Connect

    Fenfen Zhu; Masaki Takaoka; Kenji Shiota; Kazuyuki Oshita; Yoshinori Kitajima [Kyoto University, Kyoto (Japan). Department of Urban and Environmental Engineering

    2008-06-01

    Chloride content is a critical problem for the reuse of fly ash as a raw material in cement, and the method used by recyclers to reduce the fly ash chloride content depends on the chemical form of the chlorides. However, limited information is available on the quantitative distribution of chlorides and the identity of some chlorides such as Friedel's salt. We examined chloride forms and percentages using X-ray absorption near edge structure and X-ray diffraction analyses, as well as corresponding washing experiments. Approximately 15% of the chlorine in raw fly ash was estimated to be in the form of NaCl, 10% in KCl, 50% in CaCl{sub 2}, and the remainder in the form of Friedel's salt. Fly ash collected in a bag filter with the injection of calcium hydroxide for acid gas removal (CaFA) contained 35% chlorine as NaCl, 11% as KCl, 37% as CaCl{sub 2}, 13% as Friedel's salt, and the remaining 4% as CaClOH. In fly ash collected in a bag filter with the injection of sodium bicarbonate for acid gas removal (NaFA), approximately 79% of chlorine was in NaCl, 12% was in KCl, and 9% was in Friedel's salt. 25 refs., 4 figs., 4 tabs.

  17. Plutonium metal and alloy preparation by molten chloride reduction

    SciTech Connect

    Reavis, J.G.

    1984-01-01

    Satisfactory reduction of molten plutonium trichloride (pure and in combination with 20 wt % sodium chloride) by calcium, lanthanum, and cerium has been demonstrated on the 10-g scale. The yields were satisfactory for this scale of operation, and it is indicated that these reductions may be useful for large-scale operations. Significant separations of plutonium from rare earth impurities was demonstrated for lanthanum and cerium reductions. Preparation of plutonium-cerium and plutonium-cerium-cobalt alloys during reduction was also demonstrated.

  18. Get Enough Calcium

    MedlinePLUS

    ... Physical Activity > Nutrition > Get Enough Calcium Get Enough Calcium The Basics Take Action! Ver en español Content ... June 26, 2015 The Basics Your body needs calcium to build strong bones when you are young ...

  19. 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 ...

  20. 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 ...

  1. The effect of the electrochemical chloride extraction treatment on steel-reinforced mortar. Part II: Microstructural characterization

    SciTech Connect

    Marcotte, T.D.; Hansson, C.M.; Hope, B.B.

    1999-10-01

    A study has been made of the changes in cement composition and microstructures resulting from electrochemical chloride extraction applied to mortar samples in which the chlorides were added with the mixing water, ingressed by ponding with an NaCl solution, or both. After exposure for 1 year, specimens with and without chlorides were subjected to an electrochemical chloride extraction treatment. Microstructural analyses of fracture surfaces through the steel/mortar interface revealed a significant alteration of the cementitious phases. In untreated samples, calcium-silicon-rich phases consistent with Types I and II calcium silicate hydrate were observed. After the extraction treatment, these phases were not detectable and instead, sodium-rich, iron-rich, and calcium-aluminum-rich phases were observed.

  2. Calcium and nitrogen balance, experiment M007

    NASA Technical Reports Server (NTRS)

    Whedon, G. D.; Lutwak, L.; Neuman, W. F.; Lachance, P. A.

    1971-01-01

    The collection of data on the response of the skeletal and muscular systems to 14-day space flights was evaluated for loss of calcium, nitrogen, and other metabolically related elements. Considerable interindividual variability was demonstrated in all experimental factors that were measured. Calcium balance became less positive and urinary phosphate excretion increased substantially in flight despite a reduction in phosphate intake. Patterns of excretion of magnesium, sodium, potassium, and chloride were different for each subject, and, in part, could be correlated with changes in adrenocortical steroid production. The principal hormonal change was a striking decrease during flight in the urinary excretion of 17-hydroxycortocosteroids. Dermal losses of calcium, magnesium, sulfate, and phosphate were insignificant during all three phases.

  3. Xenopus laevis oocyte maturation is affected by metal chlorides.

    PubMed

    Marin, Matthieu; Slaby, Sylvain; Marchand, Guillaume; Demuynck, Sylvain; Friscourt, Noémie; Gelaude, Armance; Lemière, Sébastien; Bodart, Jean-François

    2015-08-01

    Few studies have been conducted using Xenopus laevis germ cells as oocytes, though these cells offer many advantages allowing both electrophysiological studies and morphological examination. Our aim was to investigate the effects of metal (cadmium, lead, cobalt and zinc) exposures using cell biology approaches. First, cell survival was evaluated with both phenotypical and electrophysiological approaches. Secondly, the effect of metals on oocyte maturation was assessed with morphological observations and electrophysiological recordings. From survival experiments, our results showed that metal chlorides did not affect cell morphology but strongly depolarized X. laevis oocyte resting potential. In addition, cadmium chloride was able to inhibit progesterone-induced oocyte maturation. By contrast, zinc, but also to a lesser extent cadmium, cobalt and lead, were able to enhance spontaneous oocyte maturation in the absence of progesterone stimulation. Finally, electrophysiological recordings revealed that some metal chlorides (lead, cadmium) exposures could disturb calcium signaling in X. laevis oocyte by modifying calcium-activated chloride currents. Our results demonstrated the high sensitivity of X. laevis oocytes toward exogenous metals such as lead and cadmium. In addition, the cellular events recorded might have a predictive value of effects occurring later on the ability of oocytes to be fertilized. Together, these results suggest a potential use of this cellular lab model as a tool for ecotoxicological assessment of contaminated fresh waters. PMID:25957907

  4. Air bubble contact with endothelial cells in vitro induces calcium influx and IP3-dependent release of calcium stores

    PubMed Central

    Sobolewski, Peter; Kandel, Judith; Klinger, Alexandra L.

    2011-01-01

    Gas embolism is a serious complication of decompression events and clinical procedures, but the mechanism of resulting injury remains unclear. Previous work has demonstrated that contact between air microbubbles and endothelial cells causes a rapid intracellular calcium transient and can lead to cell death. Here we examined the mechanism responsible for the calcium rise. Single air microbubbles (50–150 ?m), trapped at the tip of a micropipette, were micromanipulated into contact with individual human umbilical vein endothelial cells (HUVECs) loaded with Fluo-4 (a fluorescent calcium indicator). Changes in intracellular calcium were then recorded via epifluorescence microscopy. First, we confirmed that HUVECs rapidly respond to air bubble contact with a calcium transient. Next, we examined the involvement of extracellular calcium influx by conducting experiments in low calcium buffer, which markedly attenuated the response, or by pretreating cells with stretch-activated channel blockers (gadolinium chloride or ruthenium red), which abolished the response. Finally, we tested the role of intracellular calcium release by pretreating cells with an inositol 1,4,5-trisphosphate (IP3) receptor blocker (xestospongin C) or phospholipase C inhibitor (neomycin sulfate), which eliminated the response in 64% and 67% of cases, respectively. Collectively, our results lead us to conclude that air bubble contact with endothelial cells causes an influx of calcium through a stretch-activated channel, such as a transient receptor potential vanilloid family member, triggering the release of calcium from intracellular stores via the IP3 pathway. PMID:21633077

  5. Molecular Structure of Thionyl chloride

    NSDL National Science Digital Library

    2002-10-01

    Thionyl chloride is a slightly yellowish liquid with an intense odor and low viscosity. It reacts with lithium to produce lithium chloride and is a good solvent for most organic compounds. Other uses of thionyl chloride include as an intermediate for the production of pharmaceutically active ingredients, as an electrolyte in lithium batteries, and in crop protection.

  6. Sodium Chloride (Catheter Flush) Injection

    MedlinePLUS

    ... use a sodium chloride flush several times a day. Your health care provider will determine the number of sodium chloride flushes you will need a day. ... health care provider probably will give you several days supply of sodium chloride. You will be told ...

  7. Recovery of soluble chloride salts from the wastewater generated during the washing process of municipal solid wastes incineration fly ash.

    PubMed

    Tang, Hailong; Erzat, Aris; Liu, Yangsheng

    2014-01-01

    Water washing is widely used as the pretreatment method to treat municipal solid waste incineration fly ash, which facilitates the further solidification/stabilization treatment or resource recovery of the fly ash. The wastewater generated during the washing process is a kind of hydrosaline solution, usually containing high concentrations of alkali chlorides and sulphates, which cause serious pollution to environment. However, these salts can be recycled as resources instead of discharge. This paper explored an effective and practical recovery method to separate sodium chloride, potassium chloride, and calcium chloride salts individually from the hydrosaline water. In laboratory experiments, a simulating hydrosaline solution was prepared according to composition of the waste washing water. First, in the three-step evaporation-crystallization process, pure sodium chloride and solid mixture of sodium and potassium chlorides were obtained separately, and the remaining solution contained potassium and calcium chlorides (solution A). And then, the solid mixture was fully dissolved into water (solution B obtained). Finally, ethanol was added into solutions A and B to change the solubility of sodium, potassium, and calcium chlorides within the mixed solvent of water and ethanol. During the ethanol-adding precipitation process, each salt was separated individually, and the purity of the raw production in laboratory experiments reached about 90%. The ethanol can be recycled by distillation and reused as the solvent. Therefore, this technology may bring both environmental and economic benefits. PMID:25176491

  8. Transformation of amorphous calcium carbonate to rod-like single crystal calcite via "copying" collagen template.

    PubMed

    Xue, Zhonghui; Hu, Binbin; Dai, Shuxi; Du, Zuliang

    2015-10-01

    Collagen Langmuir films were prepared by spreading the solution of collagen over deionized water, CaCl2 solution and Ca(HCO3)2 solution. Resultant collagen Langmuir monolayers were then compressed to a lateral pressure of 10mN/m and held there for different duration, allowing the crystallization of CaCO3. The effect of crystallization time on the phase composition and microstructure of CaCO3 was investigated. It was found that amorphous calcium carbonate (ACC) was obtained at a crystallization time of 6h. The amorphous CaCO3 was transformed to rod-like single crystal calcite crystals at an extended crystallization time of 12h and 24h, via "copying" the symmetry and dimensionalities of collagen fibers. Resultant calcite crystallites were well oriented along the longitudinal axis of collagen fibers. The ordered surface structure of collagen fibers and electrostatic interactions played key roles in tuning the oriented nucleation and growth of the calcite crystallites. The mineralized collagen possessing both desired mechanical properties of collagen fiber and good biocompatibility of calcium carbonate may be assembled into an ideal biomaterial for bone implants. PMID:26117783

  9. Fermentation profile of green Spanish-style Manzanilla olives according to NaCl content in brine.

    PubMed

    Bautista-Gallego, J; Arroyo-López, F N; Romero-Gil, V; Rodríguez-Gómez, F; García-García, P; Garrido-Fernández, A

    2015-08-01

    This work studies the effects of the partial substitution of NaCl with potassium and calcium chloride salts on the fermentation profile of Spanish-style green Manzanilla olives. For this purpose, response surface methodology based in an enlarged simplex centroid mixture design with constrain (?salts = 100 g/L) was used. Regarding to physicochemical characteristics, pH decreased when CaCl2 increased, titratable acidity was lower in presence of KCl while combined acidity increased as the contents of KCl and CaCl2 were close to the barycentre of the experiment (?33.33% each salt). Regarding to microbiological profile, Enterobacteriaceae growth was slight stimulated in presence of high CaCl2 contents, yeast patterns were not linked to the initial brine compositions, while the maximum lactic acid bacteria population decreased slightly as KCl and CaCl2 increased in the proportion 1:1, although a moderate (equilibrated) content of both may be stimulating. Results obtained in this work show that Spanish-style green Manzanilla cv. can be fermented in diverse mixtures of chloride salts, albeit the initial CaCl2 should be limited to 20-30 g/L to prevent excessive Enterobacteriaceae growth; combining it with a similar proportion of KCl may also improve LAB predominance. PMID:25846915

  10. Effect of dietary salt intake on circadian calcium metabolism, bone turnover, and calcium oxalate kidney stone risk in postmenopausal women

    Microsoft Academic Search

    Linda K. Massey

    2005-01-01

    Increasing dietary salt (sodium chloride) increases urinary calcium excretion, which may increase the risk of developing osteoporosis and kidney stones. Ten postmenopausal women without osteoporosis or kidney stones who were not undergoing hormone replacement therapy ate all meals in a metabolic unit for 14 days: 7 days at each salt level in a crossover design. The 2 diets differed only

  11. Optimal Intracellular Calcium Signaling

    Microsoft Academic Search

    J. W. Shuai; P. Jung

    2002-01-01

    In many cell types, calcium is released from internal stores through calcium release channels upon external stimulation (e.g., pressure or receptor binding). These channels are clustered with a typical cluster size of about 20 channels, generating stochastic calcium puffs. We find that the clustering of the release channels in small clusters increases the sensitivity of the calcium response, allowing for

  12. Chloride channels as drug targets

    PubMed Central

    Verkman, Alan S.; Galietta, Luis J. V.

    2013-01-01

    Chloride channels represent a relatively under-explored target class for drug discovery as elucidation of their identity and physiological roles has lagged behind that of many other drug targets. Chloride channels are involved in a wide range of biological functions, including epithelial fluid secretion, cell-volume regulation, neuroexcitation, smooth-muscle contraction and acidification of intracellular organelles. Mutations in several chloride channels cause human diseases, including cystic fibrosis, macular degeneration, myotonia, kidney stones, renal salt wasting and hyperekplexia. Chloride-channel modulators have potential applications in the treatment of some of these disorders, as well as in secretory diarrhoeas, polycystic kidney disease, osteoporosis and hypertension. Modulators of GABAA (?-aminobutyric acid A) receptor chloride channels are in clinical use and several small-molecule chloride-channel modulators are in preclinical development and clinical trials. Here, we discuss the broad opportunities that remain in chloride-channel-based drug discovery. PMID:19153558

  13. Dysbalance of Astrocyte Calcium under Hyperammonemic Conditions

    PubMed Central

    Haack, Nicole; Dublin, Pavel; Rose, Christine R.

    2014-01-01

    Increased brain ammonium (NH4+/NH3) plays a central role in the manifestation of hepatic encephalopathy (HE), a complex syndrome associated with neurological and psychiatric alterations, which is primarily a disorder of astrocytes. Here, we analysed the influence of NH4+/NH3 on the calcium concentration of astrocytes in situ and studied the underlying mechanisms of NH4+/NH3-evoked calcium changes, employing fluorescence imaging with Fura-2 in acute tissue slices derived from different regions of the mouse brain. In the hippocampal stratum radiatum, perfusion with 5 mM NH4+/NH3 for 30 minutes caused a transient calcium increase in about 40% of astrocytes lasting about 10 minutes. Furthermore, the vast majority of astrocytes (?90%) experienced a persistent calcium increase by ?50 nM. This persistent increase was already evoked at concentrations of 1–2 mM NH4+/NH3, developed within 10–20 minutes and was maintained as long as the NH4+/NH3 was present. Qualitatively similar changes were observed in astrocytes of different neocortical regions as well as in cerebellar Bergmann glia. Inhibition of glutamine synthetase resulted in significantly larger calcium increases in response to NH4+/NH3, indicating that glutamine accumulation was not a primary cause. Calcium increases were not mimicked by changes in intracellular pH. Pharmacological inhibition of voltage-gated sodium channels, sodium-potassium-chloride-cotransporters (NKCC), the reverse mode of sodium/calcium exchange (NCX), AMPA- or mGluR5-receptors did not dampen NH4+/NH3-induced calcium increases. They were, however, significantly reduced by inhibition of NMDA receptors and depletion of intracellular calcium stores. Taken together, our measurements show that sustained exposure to NH4+/NH3 causes a sustained increase in intracellular calcium in astrocytes in situ, which is partly dependent on NMDA receptor activation and on release of calcium from intracellular stores. Our study furthermore suggests that dysbalance of astrocyte calcium homeostasis under hyperammonemic conditions is a widespread phenomenon, which might contribute to the disturbance of neurotransmission during HE. PMID:25153709

  14. Measurement of shift in K X-ray peak energies of potassium and calcium in different compounds using EDXRF

    NASA Astrophysics Data System (ADS)

    Kaur, Kamaldip; Mittal, Raj

    2014-12-01

    Energy shifts in K X-ray peaks of potassium and calcium in different chemical compounds have been determined from their X-ray spectra recorded in an energy dispersive X-ray fluorescence (EDXRF) set-up. The set-up comprises low-power X-ray tube photon source and Si(PIN) detector (AMPTEK model XR-100 CR). A statistical procedure has been followed to determine the shifts and t-test was applied to find the statistical significance of the results. The shifts were determined in potassium compounds; KCl, KBr, KI, K2CO3, K2Cr2O7, K2CrO4, K2SO4, K3Fe(CN)6, K4Fe(CN)6, KHSO4, KMnO4 and KSCN with KNO3 as reference and in calcium compounds; Ca(NO3)2 · 4H2O, Ca(OH)2, CaCl2, CaCO3, CaSO3 and CaSO4 · 2H2O with CaO as reference and correlated with differences in electro-negativity, number of ligands, structural changes, type of bonding, axial distances, etc. in the compounds. The shifts in potassium compounds have been evaluated for the first time while the same for calcium compounds almost agree well with the earlier reported measurements in literature.

  15. Marine macroalga Sargassum horneri as biosorbent for heavy metal removal: roles of calcium in ion exchange mechanism.

    PubMed

    Southichak, B; Nakano, K; Nomura, M; Chiba, N; Nishimura, O

    2008-01-01

    Brown seaweed Sargassum horneri, a troublesome biomass scattered along the seashore, was utilized as a biosorbent for Pb(II) removal from aqueous solutions. The Pb(II) adsorption by brown seaweed was enhanced by pretreatment with CaCl(2), and the Langmuir adsorption isotherm equation showed a maximum capacity of a Q(max) of 0.696 mmol/g and a b value of 94.33 L/mmol. Results obtained from the mass-balance equation derived from the simulation model of the Langmuir adsorption isotherm suggested that the adsorption performance of brown seaweed biosorbent was sufficient to reduce the concentration of Pb(II) to meet the range of WHO guideline. The mechanism, as elucidated using pH monitoring, adsorption rate and ion exchange model, involved the rapid pH change of metal solutions that led to high reaction rate and Pb(II) uptake in the first 30 min of the biosorption process. The energy X-ray analysis's result confirmed the sharp reduction of calcium content in the biosorbent after Pb(II) adsorption. The amount of calcium ions released from the biosorbent was about 1.5 times the amount of Pb(II) adsorbed and proved the role of calcium in the ion exchange mechanism. These adsorption equilibrium and mechanistic studies provide useful information for system design and performance prediction of biosorption processes. PMID:18725741

  16. Update on Calcium Signaling Calcium Signaling through Protein Kinases. The

    E-print Network

    Sheen, Jen

    Update on Calcium Signaling Calcium Signaling through Protein Kinases. The Arabidopsis Calcium protein kinase activities occur through calcium-dependent protein kinases (CDPKs). These novel calcium provides a valuable opportunity to understand the plant calcium-signaling network. Calcium is a ubiquitous

  17. Chloride and Salinity

    NSDL National Science Digital Library

    2011-07-15

    This learning activity from the Advanced Technology Environmental and Energy Center (ATEEC) will provide a good introduction for students studying chloride and salinity. A list of required materials is included as well as the step by step procedure for conducting the experiment. Student worksheets are also included. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

  18. Chloride inhibition of nitrite uptake for non-teleost Actinopterygiian fishes.

    PubMed

    Boudreaux, Perry J; Ferrara, Allyse M; Fontenot, Quenton C

    2007-06-01

    Fish that transport environmental chloride with a gill uptake mechanism (gill epithelial Cl(-)/HCO(3)(-)cotransport exchange system), also transport nitrite into plasma through the same mechanism. Because of the relationship between nitrite uptake and the gill chloride uptake mechanism, nitrite uptake can provide insight regarding the method of chloride uptake for fish. This study was designed to determine if non-teleost fishes concentrate nitrite in their plasma, and to determine if chloride inhibits nitrite uptake in non-teleost fish. To determine if bowfin Amia calva, spotted gar Lepisosteus oculatus, alligator gar Atractosteus spatula, and paddlefish Polyodon spathula concentrate environmental nitrite in their plasma, individuals were exposed to concentrations of 0, 1, 10, or 100 mg/L nitrite-N. After exposure, all species had plasma nitrite-N concentrations greater than environmental levels. To determine if chloride inhibits nitrite uptake for spotted gar, alligator gar, and paddlefish, fish were exposed to 1 mg/L nitrite-N and 20 mg/L chloride as calcium chloride, or to 1 mg/L nitrite-N only. Chloride effectively prevented nitrite from being concentrated in the plasma of all species. It appears that non-teleost fish concentrate nitrite in their plasma via their chloride uptake mechanism and that this is an ancestral characteristic for teleost. PMID:17344081

  19. Biochemical and functional interactions of a selective kappa opioid agonist with calcium

    SciTech Connect

    VonVoigtlander, P.F.; Ochoa, M.C.; Lewis, R.A.

    1987-01-01

    The discovery of the selective kappa opioid receptor agonist, U-50488H, has provided a tool for the study of the mechanisms and function of the kappa receptor-effector. We have investigated the interactions of this compound with calcium in several biochemical and functional studies to assess the involvement of calcium mechanisms in the kappa receptor-linked effector. In rat brain synaptosomes, U-50488H attenuated the uptake of /sup 45/Ca++ induced by K+ (40 mM) depolarization. This effect was concentration-related (U-50488H 10(-5) to 10(-7) M), was apparent in short (8-second) but not longer (1-minute) term incubations, and did not occur in the presence of a non-polarizing concentration (5.6 mM) of K+. Naloxone (10(-7) M) did not block this effect of U-50488H (10(-6) M), and higher concentrations (10(-5) M) alone blocked calcium uptake. We have found that the binding of the depolarizing amino acid analog, kainic acid, is enhanced by CaCl2. U-50488H (10(-4) to 10(-6) M) blocks this enhancement of /sup 3/H-kainic acid binding in vitro and also blocks the in vivo effects of kainic acid. In mice, intravenous injection of kainic acid causes scratching, convulsions, and death, depending on the dose administered. U-50488H blocks all of these effects (ED50 = 4.5 mg/kg for antagonism of convulsions induced by 27.5 mg/kg kainic acid). The convulsions induced by intracerebroventricularly administered kainic acid are also blocked by U-50488H as are those induced by similarly administered Bay K 8644, a calcium channel activator. All of these anticonvulsant effects of U-50488H were antagonized by naltrexone. Together these data indicate that the kappa agonist U-50488H has functionally relevant interactions with depolarization-related Ca++ mechanisms in the central nervous system.

  20. Acute effects of prolactin on passive calcium absorption in the small intestine by in vivo perfusion technique.

    PubMed

    Krishnamra, N; Wirunrattanakij, Y; Limlomwongse, L

    1998-02-01

    The acute effect of intraperitoneally administered prolactin (0.2, 0.4, and 0.6 mg/kg body weight) on passive calcium transport in duodenum, proximal jejunum, and ileum of sexually mature female Wistar rats was investigated by using an in vivo perfusion technique. Test solution containing (in mM) NaCl, 100; KCl, 4.7; MgSO4, 1.2; CaCl2, 20; D-glucose, 11; sodium ferrocyanide (Na4Fe(CN)6), an index of net water transport, 20; and 0.7 microCi 45CaCl2 (1 Ci = 37 GBq) was perfused through the 10-cm intestinal loop for 60 min. Results showed that 0.4 mg prolactin/kg body weight significantly increased duodenal net Ca absorption (net Ca) from 23.81 +/- 1.84 to 30.56 +/- 1.57 mmol/g dry weight (p < 0.05) by stimulating the lumen to plasma calcium flux (CaL-P). The jejunum responded to 0.2, 0.4, and 0.6 mg prolactin/kg body weight by reversing from net Ca absorption of 18.60 +/- 1.70 mmol/g dry weight to net secretion of -3.30 +/- 1.56, -10.39 +/- 2.21, and -11.79 +/- 2.04 mmol/g dry weight (p < 0.01), respectively, as a result of a dose-dependent increase in plasma to lumen calcium flux (CaP-L). Calcium fluxes in the ileum on the other hand did not respond to prolactin. There was a close correlation between net water flux and net calcium flux in all three intestinal segments under basal condition regardless of the luminal sodium concentration. However, this correlation was lost after prolactin administration, which while having no effect on net water flux, altered the duodenal and jejunal calcium fluxes. By varying the luminal concentration of sodium, it was found that the stimulatory effect of 0.4 mg prolactin/kg body weight on the duodenal CaL-P was reduced when compared with control, i.e., 17.84 +/- 0.91 vs. 26.64 +/- 1.05 mmol/g dry weight at a sodium concentration of 180 mM, and 14.48 +/- 0.99 vs. 20.12 +/- 1.34 mmol/g dry weight at a sodium concentration of 140 mM. At a sodium concentration of 80 mM, the prolactin effect was absent. Since duodenal Na(+)-K+ ATPase activity was increased by prolactin from 3.77 +/- 0.16 to 4.95 +/- 0.30 mumol Pi.mg-1 protein.h-1 (p < 0.05), sodium dependency of the prolactin-enhanced lumen to plasma calcium flux may be related to both sodium-induced water flow and calcium-sodium exchange across the basolateral membrane. Thus, it was postulated that under basal condition, net calcium transport in the small intestine occurred with the sodium-induced water transport along the paracellular pathway. However, after prolactin administration, this association was lost. Prolactin-enhanced lumen to plasma calcium flux in the duodenum was sodium dependent and involved the Na(+)-K+ ATPase activity. In the proximal jejunum, prolactin stimulated plasma to lumen calcium flux, but the mechanism was not known. PMID:9635155

  1. Modeling acid-gas generation from boiling chloride brines

    PubMed Central

    2009-01-01

    Background This study investigates the generation of HCl and other acid gases from boiling calcium chloride dominated waters at atmospheric pressure, primarily using numerical modeling. The main focus of this investigation relates to the long-term geologic disposal of nuclear waste at Yucca Mountain, Nevada, where pore waters around waste-emplacement tunnels are expected to undergo boiling and evaporative concentration as a result of the heat released by spent nuclear fuel. Processes that are modeled include boiling of highly concentrated solutions, gas transport, and gas condensation accompanied by the dissociation of acid gases, causing low-pH condensate. Results Simple calculations are first carried out to evaluate condensate pH as a function of HCl gas fugacity and condensed water fraction for a vapor equilibrated with saturated calcium chloride brine at 50-150°C and 1 bar. The distillation of a calcium-chloride-dominated brine is then simulated with a reactive transport model using a brine composition representative of partially evaporated calcium-rich pore waters at Yucca Mountain. Results show a significant increase in boiling temperature from evaporative concentration, as well as low pH in condensates, particularly for dynamic systems where partial condensation takes place, which result in enrichment of HCl in condensates. These results are in qualitative agreement with experimental data from other studies. Conclusion The combination of reactive transport with multicomponent brine chemistry to study evaporation, boiling, and the potential for acid gas generation at the proposed Yucca Mountain repository is seen as an improvement relative to previously applied simpler batch evaporation models. This approach allows the evaluation of thermal, hydrological, and chemical (THC) processes in a coupled manner, and modeling of settings much more relevant to actual field conditions than the distillation experiment considered. The actual and modeled distillation experiments do not represent expected conditions in an emplacement drift, but nevertheless illustrate the potential for acid-gas generation at moderate temperatures (<150°C). PMID:19917082

  2. COMPARISON OF DIFFERENCES BETWEEN PWD/PhJ AND C57BL/6J MICE IN CALCIUM SOLUTION PREFERENCES AND CHORDA TYMPANI NERVE RESPONSES

    PubMed Central

    Cherukuri, Chandra M.; McCaughey, Stuart A.; Tordoff, Michael G.

    2011-01-01

    We used the C57BL/6J (B6) and PWD/PhJ (PWD) mouse strains to investigate the controls of calcium intake. Relative to the B6 strain, the PWD strain had higher preferences in two-bottle choice tests for CaCl2, calcium lactate (CaLa), MgCl2, citric acid and quinine hydrochloride, but not for sucrose, KCl or NaCl. We also measured taste-evoked chorda tympani (CT) nerve activity in response to oral application of these compounds. Electrophysiological results paralleled the preference test results, with larger responses in PWD than in B6 mice for those compounds that were more highly preferred for the former strain. The strain differences were especially large for tonic, rather than phasic, chorda tympani activity. These data establish the PWD strain as a “calcium-preferring” strain and suggest that differences between B6 and PWD mice in taste transduction or a related peripheral event contributes to the differences between the strains in preferences for calcium solutions. PMID:21219921

  3. Expression of CLCN Voltage-gated Chloride Channel Genes in Human Blood Vessels

    Microsoft Academic Search

    Fred S. Lamb; Gerald H. Clayton; Bei-Xing Liu; Roderic L. Smith; Thomas J. Barna; Brian C. Schutte

    1999-01-01

    Chloride (Cl) ion channels play a critical role in the response of both vascular smooth muscle (VSM) and endothelial (ENDO) cells to agonist stimulation. In VSM, agonist-induced Cl currents produce membrane depolarization, resulting in calcium influx through voltage-sensitive channels. ENDO cells also activate Cl currents after either agonist applicaiton or perturbation of cell volume. Although some of these currents have

  4. Fertilizer Facts: May 1998, Number 18 Spring Wheat Response to Potassium and Chloride

    E-print Network

    Lawrence, Rick L.

    , potassium nitrate, and ammonium chloride. Plot size was six rows wide and 20 feet long. Locations were samples. Calcium nitrate extractable Cl was measured from 0-1 foot and 1-2 foot depth soil samples. Grain soils, sufficient soil water for crop production (as determined by the Brown probe), and good

  5. Molecular Structure of Ferric chloride

    NSDL National Science Digital Library

    2002-08-27

    Ferric chloride is a corrosive chemical, thus, it is used to deodorize sewage and industrial waste by partially reducing to ferrous chloride. It is also employed as an engraving reagent on metal surfaces. Other applications include its use as a flocculating agent in water treatment. Ferric chloride is a hazardous chemical that irritates the skin and eyes and is toxic if ingested, however it can be used as a reagent in pharmaceutical preparations.

  6. Chloride channels as drug targets

    Microsoft Academic Search

    Luis J. V. Galietta; Alan S. Verkman

    2008-01-01

    Chloride channels represent a relatively under-explored target class for drug discovery as elucidation of their identity and physiological roles has lagged behind that of many other drug targets. Chloride channels are involved in a wide range of biological functions, including epithelial fluid secretion, cell-volume regulation, neuroexcitation, smooth-muscle contraction and acidification of intracellular organelles. Mutations in several chloride channels cause human

  7. Effect of Calcium Sprays on Mechanical Strength and Cell Wall Fractions of Herbaceous Peony (Paeonia Lactiflora Pall.) Inflorescence Stems

    PubMed Central

    Li, Chengzhong; Tao, Jun; Zhao, Daqiu; You, Chao; Ge, Jintao

    2012-01-01

    Calcium is an essential element and imparts significant structural rigidity to the plant cell walls, which provide the main mechanical support to the entire plant. In order to increase the mechanical strength of the inflorescence stems of herbaceous peony, the stems are treated with calcium chloride. The results shows that preharvest sprays with 4% (w/v) calcium chloride three times after bud emergence are the best at strengthening “Da Fugui” peonies’ stems. Calcium sprays increased the concentrations of endogenous calcium, total pectin content as well as cell wall fractions in herbaceous peonies stems, and significantly increased the contents of them in the top segment. Correlation analysis showed that the breaking force of the top segment of peonies’ stems was positively correlated with the ratio of water insoluble pectin to water soluble pectin (R = 0.673) as well as lignin contents (R = 0.926) after calcium applications. PMID:22606005

  8. Polar Calcium Flux in Sunflower Hypocotyl Segments 1

    PubMed Central

    de Guzman, Constancio C.; dela Fuente, Rollo K.

    1986-01-01

    Calcium flux in sunflower (Helianthus annuus L. cv Russian mammoth) hypocotyl was measured with a Ca2+ electrode as the increase or decrease in Ca2+ in an aqueous solution (10 micromolar CaCl2) in contact with either the basal or apical end of 20 millimeter segments. Ca2+ efflux was significantly higher at the apical end compared with the basal end; this apparent polarity was maintained even when the segments were inverted. No significant difference was observed in the cation exchange capacity of apical and basal cell walls that could explain the difference in Ca2+ efflux at opposite ends of the hypocotyl segment. The presence of exogenous indoleacetic acid (IAA) in the segment medium resulted in the promotion of both Ca2+ efflux and segment elongation. However, osmotic inhibition of the IAA-induced elongation did not result in inhibiting the IAA-induced Ca2+ efflux. Ca2+ efflux was inhibited by cyanide. Lowering the temperature from 25°C also caused the gradual reduction of Ca2+ efflux; at 5°C the hypocotyl segments showed a net absorption of Ca2+ from the segment medium. These findings support the suggestion that: (a) the observed Ca2+ efflux in hypocotyl segments is probably the manifestation of the system which maintains the transmembrane Ca2+ gradient at the cellular level. (b) The acropetal polarity of Ca2+ efflux may be the result of the involvement of Ca2+ in the basipetal transport of IAA. Images Fig. 2 Fig. 3 Fig. 5 Fig. 6 PMID:16664830

  9. 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.

  10. Exogenous Calcium Alleviates Low Night Temperature Stress on the Photosynthetic Apparatus of Tomato Leaves

    PubMed Central

    Ni, Yang; Meng, Zhaojuan; Lu, Tao; Li, Tianlai

    2014-01-01

    The effect of exogenous CaCl2 on photosystem I and II (PSI and PSII) activities, cyclic electron flow (CEF), and proton motive force of tomato leaves under low night temperature (LNT) was investigated. LNT stress decreased the net photosynthetic rate (Pn), effective quantum yield of PSII [Y(II)], and photochemical quenching (qP), whereas CaCl2 pretreatment improved Pn, Y(II), and qP under LNT stress. LNT stress significantly increased the non-regulatory quantum yield of energy dissipation [Y(NO)], whereas CaCl2 alleviated this increase. Exogenous Ca2+ enhanced stimulation of CEF by LNT stress. Inhibition of oxidized PQ pools caused by LNT stress was alleviated by CaCl2 pretreatment. LNT stress reduced zeaxanthin formation and ATPase activity, but CaCl2 pretreatment reversed both of these effects. LNT stress caused excess formation of a proton gradient across the thylakoid membrane, whereas CaCl2 pretreatment decreased the said factor under LNT. Thus, our results showed that photoinhibition of LNT-stressed plants could be alleviated by CaCl2 pretreatment. Our findings further revealed that this alleviation was mediated in part by improvements in carbon fixation capacity, PQ pools, linear and cyclic electron transports, xanthophyll cycles, and ATPase activity. PMID:24828275

  11. RESEARCH ARTICLE CALCIUM CHANNEL STRUCTURE

    E-print Network

    Napp, Nils

    RESEARCH ARTICLE CALCIUM CHANNEL STRUCTURE Structural basis for a pH-sensitive calcium leak across,3 Wayne A. Hendrickson,1,2,4,5 Qun Liu1,4 * Calcium homeostasis balances passive calcium leak and active calcium uptake. Human Bax inhibitor­1 (hBI-1) is an antiapoptotic protein that mediates a calcium leak

  12. Calcium Secretion into Milk

    Microsoft Academic Search

    Margaret C. Neville

    2005-01-01

    Ionized calcium ([Ca2+]) is present in milk at concentrations around 3 mM, a concentration that drives the formation of complexes with citrate, phosphate, and casein, thereby generating compounds that carry the major portion of calcium in milk. In humans and cows, where it has been studied, changes in milk calcium appear to be regulated by the amount of citrate and

  13. Polyfluoro-tert-alkylsulfenyl chlorides

    Microsoft Academic Search

    A. Yu. Sizov; A. F. Kolomiets; A. V. Fokin

    1988-01-01

    Polyfluoroalkylsulfenyl chlorides with tert-alkyl groups were obtained and these compounds were found to be similar to sulfenyl chlorides with primary polyfluoroalkyl groups in electrophilic addition at the C=C bond and are distinguished only in somewhat reduced reactivity.

  14. Molecular Structure of Picryl chloride

    NSDL National Science Digital Library

    2002-09-20

    Picryl chloride is ranked as one of the 100 most commonly found explosive and shock sensitive materials. It is made by reacting 2,4,6 trinitrophenol with thionyl chloride. This highly reactive compound is known to be hazardous and toxic, and to cause liver injury in mice. It is often used as a sensitization agent in mice when their cells undergo hypersensitivity studies.

  15. Modelling chloride diffusion in concrete

    Microsoft Academic Search

    Michael D. A. Thomas; Phil B. Bamforth

    1999-01-01

    Data from long-term field and laboratory studies of concrete exposed to chloride environments were analyzed using a chloride transport model developed at the University of Toronto. The results show that the incorporation of fly ash and slag may have little impact on transport properties determined at early ages (e.g., 28 days), but can lead to order of magnitude improvements in

  16. Chloride thresholds in marine concrete

    SciTech Connect

    Thomas, M. [Univ. of Toronto, Ontario (Canada). Dept. of Civil Engineering] [Univ. of Toronto, Ontario (Canada). Dept. of Civil Engineering

    1996-04-01

    This paper reports results from an ongoing study of the performance of fly ash concrete in marine exposure. Reinforced concrete specimens exposed to tidal conditions were retrieved at ages ranging from 1 to 4 years. Steel reinforcement mass losses are compared with chloride contents at the location of the bar for concrete specimens of various strength grades and with a range of fly ash levels. The maximum level of chloride that could be tolerated without significant mass loss due to corrosion was found to vary with fly ash content. This threshold chloride level decreased with increasing fly ash content; values obtained were 0.70%, 0.65%, 0.50% and 0.20% acid-soluble chloride (by mass of cementitious material) for concrete with 0%, 15%, 30% and 50% ash, respectively. Despite the lower threshold values, fly ash concrete was found to provide better protection to the steel under these conditions, due to its increased resistance to chloride ion penetration.

  17. Novel technique for phosphorus recovery from aqueous solutions using amorphous calcium silicate hydrates (A-CSHs).

    PubMed

    Okano, Kenji; Uemoto, Masahide; Kagami, Jumpei; Miura, Keiichi; Aketo, Tsuyoshi; Toda, Masaya; Honda, Kohsuke; Ohtake, Hisao

    2013-05-01

    A novel technique for phosphorus (P) recovery from aqueous solutions was developed using amorphous calcium silicate hydrates (A-CSHs). A-CSHs, which have a high Ca/Si molar ratio of 2.0 or greater, could be synthesized using unlimitedly available, inexpensive materials such as siliceous shale and calcium hydroxide. A-CSHs showed high performance for P recovery from an anaerobic sludge digestion liquor (ASDL) and the synthetic model liquor (s-ASDL) containing 89 mg PO4-P/L. After 20 min mixing, 1.5 g/L A-CSHs could remove approximately 69 and 73% PO4-P from ASDL and s-ASDL, respectively. By contrast, autoclaved lightweight concrete particles, which contained crystalline calcium silicate hydrates as a principal component, removed only 10 and 6% PO4-P from ASDL and s-ASDL, respectively, under the same experimental conditions. When A-CSHs were washed with deionized water to remove free Ca(OH)2, P removability was significantly improved (up to 82%) despite the reduction in the amount of Ca(2+) released. Unlike in the case of Ca(OH)2, no significant carbonate inhibition was observed with P removal by A-CSHs. Moreover, P removed by A-CSHs showed better settleability, filterability, and dewaterability than P precipitated with conventional CaCl2 and Ca(OH)2. The present study demonstrated that A-CSHs have great potential as a novel, beneficial material for P recovery and recycling. PMID:23497975

  18. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely...

  19. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely...

  20. Effect of supplementary cementing materials on concrete resistance against carbonation and chloride ingress

    SciTech Connect

    Papadakis, V.G.

    2000-02-01

    In this work the durability of Portland cement systems incorporating supplementary cementing materials (SCM; silica fume, low- and high-calcium fly ash) is investigated. Experimental tests simulating the main deterioration mechanisms is reinforced concrete (carbonation and chloride penetration) were carried out. It was found that for all SCM tested, the carbonation depth decreases as aggregate replacement by SCM increases, and increases as cement replacement by SCM increases. The specimens incorporating an SCM, whether it substitutes aggregate or cement, when exposed to chlorides exhibit significantly lower total chloride content for all depths from the surface, apart from a thin layer near the external surface. New parameter values were estimated and existing mathematical models were modified to describe the carbonation propagation and the chloride penetration in concrete incorporating SCM.

  1. Preparation and characterization of in situ ionic cross-linked pectin films: unique biodegradable polymers.

    PubMed

    Penhasi, Adel; Meidan, Victor M

    2014-02-15

    The study aimed to investigate the swelling and degradation of calcium pectinate (CaP) films that were cross-linked by the innovative approach of adding aqueous calcium chloride (CaCl2) to pre-formed pectin films in situ. The films, cast from low methoxy pectin, were dried and cross-linked by immersion in a selected CaCl2 solution for a selected period. It was found that CaCl2 concentration, immersion time, and temperature affected the films' dissolution and swelling behaviors in simulated intestinal fluid. With lower CaCl2 concentration, more time was needed to form a proper film. Heat accelerated the cross-linking reaction, probably by elevating the cross-linked solution flux into the matrix. Depending upon cross-linking conditions, similar calcium contents in the CaP films resulted in different swelling and degradation behaviors. The degree of pectin esterification (DE) affected the films' degradation rate. The role of pectin molecular weight and DE on the films' mechanical properties was determined by stress/strain analysis. PMID:24507280

  2. Porous matrix of calcium alginate/gelatin with enhanced properties as scaffold for cell culture.

    PubMed

    Cuadros, Teresa R; Erices, Alejandro A; Aguilera, José M

    2015-06-01

    Hydrophilic polysaccharides can be used to prepare porous matrices with a range of possible applications. One such application involves acting as scaffolds for cell culture. A new homogeneous and highly porous biopolymeric porous matrix (BPM) of calcium alginate/gelatin was produced by following a simple process. The key to this process was the selection of the porogen (aerated gelatin). The preparation technique comprises the following steps: incorporating the porogen into the solution of alginate (3%), molding, cross-linking the alginate in 1.41% CaCl2 (maximum gel strength; Cuadros et al., 2012. Carbohydr. Polym. 89, 1198-1206), molding, leaching and lyophilization. Cylinders of BPM were shown to have a relative density of 0.0274 ± 0.002, porosity of 97.26 ± 0.18%, an average internal pore size of 204 ± 58 µm and enhanced mechanical properties, while imbibing more than 11 times their dry weight in water. In vitro cell culture testing within BPM using mesenchymal stem cells was demonstrated by MTT assays and expression of alkaline phosphatase. The BPM provided a suitable microenvironment for seeding, adhesion, proliferation and osteogenic differentiation of cells. The preparation technique and resulting porous matrix represent potential tools for future study and further applications. PMID:25661688

  3. Calcium buffering is required to maintain bone stiffness in saline solution.

    PubMed

    Gustafson, M B; Martin, R B; Gibson, V; Storms, D H; Stover, S M; Gibeling, J; Griffin, L

    1996-09-01

    This work determined whether mineral dissolution due to prolonged testing or storage of bone specimens in normal saline would alter their elastic modulus. In one experiment, small pieces of equine third metacarpal bone were soaked in normal saline supplemented with varying amounts of CaCl2. Changing Ca ion concentrations in the bath were monitored and the equilibrium concentration was determined. In a second experiment, the elastic moduli of twenty 4 x 10 x 100 mm equine third metacarpal beams were determined non-destructively in four-point bending. Half the beams were then soaked for 10 days in normal saline, and the other half in saline buffered to the bone mineral equilibrium point with Ca ions. Modulus measurements were repeated at 6 and 10 days. The equilibrium Ca ion concentration for bone specimens was found to be 57.5 mg l-1. The modulus of bone specimens soaked in normal saline significantly diminished 2.4%, whereas the modulus of those soaked in calcium-buffered saline did not change significantly. PMID:8872276

  4. Reversible alkaline inactivation of lignin peroxidase involves the release of both the distal and proximal site calcium ions and bishistidine co-ordination of the haem.

    PubMed Central

    George, S J; Kvaratskhelia, M; Dilworth, M J; Thorneley, R N

    1999-01-01

    Phanerochaete chrysosporium lignin peroxidase isoenzyme H2 (LiP H2) exhibits a transition to a stable, inactive form at pH 9.0 with concomitant spectroscopic changes. The Söret peak intensity decreases some 55% with a red shift from 408 to 412 nm; the bands at 502 nm and 638 nm disappear and the peak at 536 nm increases. The EPR spectrum changes from a signal typical of high spin ferric haem to an exclusively low spin spectrum with g=2.92, 2.27, 1.50. These data indicate that the active pentaco-ordinated haem is converted into a hexaco-ordinated species at alkaline pH. Room temperature near-IR MCD data coupled with the EPR spectrum allow us to assign the haem co-ordination of alkali-inactivated enzyme as bishistidine. Re-acidification of the alkali-inactivated enzyme to pH 6 induces further spectroscopic changes and generates an irreversibly inactivated species. By contrast, a pH shift from 9.0 to 6.0 with simultaneous addition of 50 mM CaCl(2) results in the recovery of the initial activity together with the spectroscopic characteristics of the native ferric enzyme. Incubating with 50 mM CaCl(2) at a pH between 6.0 and 9.0 can also re-activate the enzyme. Divalent metals other than Ca(2+) do not result in restoration of activity. Experiments with (45)Ca indicate that two tightly bound calcium ions per enzyme monomer are lost during inactivation and reincorporated during subsequent re-activation, consistent with the presence of two structural Ca(2+) ions in LiP H2. It is concluded that both the structural Ca(2+) ions play key roles in the reversible alkaline inactivation of LiP H2. PMID:10548556

  5. FOCUS | LETTERS PUBLISHED ONLINE: 25 APRIL 2010 | DOI: 10.1038/NGEO847

    E-print Network

    Priscu, John C.

    contained elevated concentrations of nitrate (5,533±626 µM), nitrite (25.3±9.2 µM) and ammonium (490.3± 82.6 processes such as nitrification and denitrification are thought to drive nitrous oxide production in soils), contains a groundwater- derived calcium-chloride-rich eutectic brine4 (413 g CaCl2 and 29 g NaCl kg-1 ; up

  6. Contribution of calcium oxalate to soil-exchangeable calcium

    USGS Publications Warehouse

    Dauer, Jenny M.; Perakis, Steven S.

    2013-01-01

    Acid deposition and repeated biomass harvest have decreased soil calcium (Ca) availability in many temperate forests worldwide, yet existing methods for assessing available soil Ca do not fully characterize soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it has been hypothesized that the highly insoluble biomineral Ca oxalate might represent an additional soil Ca pool that is not detected in standard measures of soil-exchangeable Ca. We asked whether several standard method extractants for soil-exchangeable Ca could also access Ca held in Ca oxalate crystals using spike recovery tests in both pure solutions and soil extractions. In solutions of the extractants ammonium chloride, ammonium acetate, and barium chloride, we observed 2% to 104% dissolution of Ca oxalate crystals, with dissolution increasing with both solution molarity and ionic potential of cation extractant. In spike recovery tests using a low-Ca soil, we estimate that 1 M ammonium acetate extraction dissolved sufficient Ca oxalate to contribute an additional 52% to standard measurements of soil-exchangeable Ca. However, in a high-Ca soil, the amount of Ca oxalate spike that would dissolve in 1 M ammonium acetate extraction was difficult to detect against the large pool of exchangeable Ca. We conclude that Ca oxalate can contribute substantially to standard estimates of soil-exchangeable Ca in acid forest soils with low soil-exchangeable Ca. Consequently, measures of exchangeable Ca are unlikely to fully resolve discrepancies in ecosystem Ca mass balance unless the contribution of Ca oxalate to exchangeable Ca is also assessed.

  7. Studies Update Vinyl Chloride Hazards.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  8. Efficacy of chlorine dioxide against Listeria monocytogenes in brine chilling solutions.

    PubMed

    Valderrama, W B; Mills, E W; Cutter, C N

    2009-11-01

    Chilled brine solutions are used by the food industry to rapidly cool ready-to-eat meat products after cooking and before packaging. Chlorine dioxide (ClO(2)) was investigated as an antimicrobial additive to eliminate Listeria monocytogenes. Several experiments were performed using brine solutions made of sodium chloride (NaCl) and calcium chloride (CaCl(2)) inoculated with L. monocytogenes and/or treated with 3 ppm of ClO(2). First, 10 and 20% CaCl(2) and NaCl solutions (pH 7.0) were inoculated with a five-strain cocktail of L. monocytogenes to obtain approximately 7 log CFU/ml and incubated 8 h at 0 degrees C. The results demonstrated that L. monocytogenes survived in 10% CaCl(2), 10 and 20% NaCl, and pure water. L. monocytogenes levels were reduced approximately 1.2 log CFU/ml in 20% CaCl(2). Second, inoculated ( approximately 7 log CFU/ml) brine solutions (10 and 20% NaCl and 10% CaCl(2)) treated with 3 ppm of ClO(2) resulted in a approximately 4-log reduction of the pathogen within 90 s. The same was not observed in a solution of 20% CaCl(2); further investigation demonstrated that high levels of divalent cations interfere with the disinfectant. Spent brine solutions from hot dog and ham chilling were treated with ClO(2) at concentrations of 3 or 30 ppm. At these concentrations, ClO(2) did not reduce L. monocytogenes. Removal of divalent cations and organic material in brine solutions prior to disinfection with ClO(2) should be investigated to improve the efficacy of the compound against L. monocytogenes. The information from this study may be useful to processing establishments and researchers who are investigating antimicrobials in chilling brine solutions. PMID:19903388

  9. Morphology and buoyancy of oil-entrapped calcium pectinate gel beads

    Microsoft Academic Search

    Pornsak Sriamornsak; Nartaya Thirawong; Satit Puttipipatkhachorn

    2004-01-01

    A new emulsion-gelation method to prepare oil-entrapped calcium pectinate gel (CaPG) beads capable of floating in the gastric\\u000a condition was designed and tested. The gel beads containing edible oil were prepared by either being gently mixed or homogenized\\u000a an oil phase and a water phase containing pectin, and then extruded into calcium chloride solution with gentle agitation at\\u000a room temperature.

  10. Screening for CLCN5 mutation in renal calcium stone formers patients

    Microsoft Academic Search

    Maria Alice P. Rebelo; Vera Tostes; Nordeval C. Araújo; Sabrina V. Martini; Bruno F. Botelho; William B. Guggino; Marcelo M. Morales

    2005-01-01

    Thirty-five patients (23 males and 12 females), age 35 ± 13 years old, presenting either idiopathic calcium nephrolithiasis, nephrocalcinosis or mild renal failure with idiopathic calcium nephrolithiasis were selected for the analysis of low molecular weight proteinuria and the possible mutations occurrence in the chloride channel gene CLCN5. The urinary ratio of ?2-microglobulin and creatinine (?2M\\/Cr) was very high in

  11. An XAFS study of nickel chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; G Cheek; K Pandya; W OGrady

    2011-12-31

    Nickel chloride was studied with cyclic voltammetry and X-ray absorption spectroscopy in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Acidic melts display metal stripping peaks which are not observed in the basic melt. EXAFS analysis shows that the nickel is tetrahedrally coordinated with chloride ions in the basic solution. In the acidic solution the nickel is coordinated by six chloride ions that are also associated with aluminum ions.

  12. Effects of brine chemistry and polymorphism on clumped isotopes revealed by laboratory precipitation of mono- and multiphase calcium carbonates

    NASA Astrophysics Data System (ADS)

    Kluge, Tobias; John, Cédric M.

    2015-07-01

    Carbonate clumped isotopes are applied to an increasing number of geological archives to address a wide range of Earth science questions. However, the effect of changes in salinity on the carbonate clumped isotope technique has not been investigated experimentally yet. In particular, evaporated sea water and diagenetic fluids differ substantially from solutions used to calibrate the clumped isotope thermometer as they exhibit high ionic concentrations of e.g., Na+, Ca2+, Mg2+, and Cl-. High ionic concentrations are known to have an impact on ?18O values, and could potentially impact the successful application of clumped isotopes to the reconstruction of diagenetic processes, including precipitation temperatures and the origin of the diagenetic fluid. In order to address the potential influence of salt ions on the clumped isotope ?47 value we precipitated CaCO3 minerals (calcite, aragonite and vaterite), hydromagnesite and mixtures of these minerals in the laboratory from solutions containing different salt ions (Na+, Ca2+, Mg2+, Cl-) at various concentrations and temperatures. The precipitation of some mineralogies was restricted to solutions with specific ionic concentrations, limiting direct comparability. NaCl-rich solutions mostly led to vaterite formation. In control experiments CaCO3 minerals (calcite and aragonite) were precipitated from a CaCO3 supersaturated solution without addition of any other ions. Our results show that calcium carbonates precipitated from high NaCl concentrations yield ?47 values identical to our NaCl-free control solution. Although addition of Mg led to the formation of hydromagnesite, it also follows the same ?47-T calibration as calcite. In contrast, ?47 values increase together with increased CaCl2 concentrations, and deviate by a few 0.01‰ from expected equilibrium values. Overall, clumped isotope values of CaCO3 minerals precipitated between 23 °C and 91 °C (with and without NaCl addition) follow a line with a slope close to results from statistical thermodynamics. We conclude for calcium carbonate and hydromagnesite that the combined effect of salt ion concentration, acid fractionation and polymorphism is negligible for Cl- and Na+ with respect to clumped isotope geochemistry, but that offsets are possible in brines containing high concentrations of CaCl2.

  13. Actin assembly in electropermeabilized neutrophils: role of intracellular calcium

    PubMed Central

    1990-01-01

    Assembly of microfilaments involves the conversion of actin from the monomeric (G) to the filamentous (F) form. The exact sequence of events responsible for this conversion is yet to be defined and, in particular, the role of calcium remains unclear. Intact and electropermeabilized human neutrophils were used to assess more directly the role of cytosolic calcium [( Ca2+]i) in actin assembly. Staining with 7-nitrobenz-2-oxa-1,3-diazole-phallacidin and right angle light scattering were used to monitor the formation of F-actin. Though addition of Ca2+ ionophores can be known to induce actin assembly, the following observations suggest that an increased [Ca2+]i is not directly responsible for receptor-induced actin polymerization: (a) intact cells in Ca2(+)-free medium, depleted of internal Ca2+ by addition of ionophore, responded to the formyl peptide fMLP with actin assembly despite the absence of changes in [Ca2+]i, assessed with Indo- 1; (b) fMLP induced a significant increase in F-actin content in permeabilized cells equilibrated with medium containing 0.1 microM free Ca2+, buffered with up to 10 mM EGTA; (c) increasing [Ca2+]i beyond the resting level by direct addition of CaCl2 to permeabilized cells resulted in actin disassembly. Conversely, lowering [Ca2+]i resulted in spontaneous actin assembly. To reconcile these findings with the actin- polymerizing effects of Ca2+ ionophores, we investigated whether A23187 and ionomycin induced actin assembly by a mechanism independent of, or secondary to the increase in [Ca2+]i. We found that the ionophore- induced actin assembly was completely inhibited by the leukotriene B4 (LTB4) antagonist LY-223982, implying that the ionophore effect was secondary to LTB4 formation, possibly by stimulation of phospholipase A2. We conclude that actin assembly is not mediated by an increase in [Ca2+]i, but rather that elevated [Ca2+]i facilitates actin disassembly, an effect possibly mediated by Ca2(+)-sensitive actin filament-severing proteins such as gelsolin. Sequential actin assembly and disassembly may be necessary for functions such as chemotaxis. PMID:2112547

  14. New method to measure the rapid chloride migration coefficient of chloride-contaminated concrete

    Microsoft Academic Search

    S. Lay; S. Liebl; H. Hilbig; P. Schießl

    2004-01-01

    The apparent chloride diffusion coefficient, Dapp, which is obtained by fitting chloride profiles as the result of time-consuming immersion tests can be substituted in a model on chloride ingress by the rapid chloride migration (RCM) coefficient of concrete, DRCM, which is determined under electrically accelerated conditions. Until now, it was not possible to measure DRCM of chloride-contaminated concrete, as already

  15. CALCIUM EQUILIBRIUM IN MUSCLE

    PubMed Central

    Gilbert, Daniel L.; Fenn, Wallace O.

    1957-01-01

    1. A study of the calcium equilibrium in isolated frog muscle has been attempted. 2. When sartorius muscles were immersed in Ca45 Ringer's solution, the surface phase took up the Ca45 in about 1 minute; the extracellular water space and connective tissue in about 30 minutes; and the intracellular space in about 300 minutes. 3. The percentages of total calcium in the whole muscle immersed in Ringer's solution was as follows: 10 per cent in the surface phase; 12 per cent in the extracellular water space; 17 per cent in the dry connective tissue; 24 per cent in the intracellular space; and 37 per cent as non-exchangeable calcium. 4. The exchange constants of isolated frog sartorius muscle to calcium has been determined. The flux of intracellular calcium in the steady state was approximately 0.8 mM/(liter hr). 5. It appears that there is a calcium pump pushing calcium out of the cell against an electrochemical gradient of about 4 cal./mM of calcium. However, since the flux is low, the maximum energy required per hour to pump calcium out of the cell against this high gradient is only about 2 cal./kg. muscle or about 1 per cent of the resting energy. PMID:13398571

  16. Crystallization of sodium chloride from a concentrated calcium chloride-potassium chloride-sodium chloride solution in a CMSMPR crystallizer: Observation of crystal size distribution and model validation

    Microsoft Academic Search

    Byung Sang Choi

    2005-01-01

    Compared to overwhelming technical data available in other advanced technologies, knowledge about particle technology, especially in particle synthesis from a solution, is still poor due to the lack of available equipment to study crystallization phenomena in a crystallizer. Recent technical advances in particle size measurement such as Coulter counter and laser light scattering have made in\\/ex situ study of some

  17. Calcium magnesium acetate production and cost reduction

    SciTech Connect

    Leuschner, A.P.

    1988-02-01

    The New York State Energy Research and Development Authority (Energy Authority), Consolidated Edison Company of New York, Inc. (ConEd), the New York State Department of Transportation (NYSDOT), the New York State Thruway Authority (NYSTA), Chevron Chemical Company, the National Corn Growers Association (NCGA), and the Massachusetts Department of Public Works (MDPW) sponsored a research program to develop technology capable of producing Calcium Magnesium Acetate (CMA), an alternative road deicer, at a quality and cost which will allow its increased use. The objectives of this program were to determine the feasibility of: (1) producing CMA from regionally available waste and low grade organic feedstocks via biochemical engineering technologies; (2) operating the fermentation at concentrated product levels to reduce energy requirements and minimize drying process costs; (3) using this production approach to produce an environmentally acceptable CMA product; and (4) using and adapting an existing facility for a CMA commercial demonstration plant. The experimental program included:(1) selection of microorganisms for their ability to grow in the absence of sodium chloride and to tolerate high concentrations of calcium, magnesium, and acetate ions; (2) analysis of waste feedstocks for their potential conversion to acetate; (3) analysis of waste organic material for impurities in CMA that could carry over into the environment; (4) batch experiments to determine pH tolerance, growth in the absence of sodium chloride (NaCl), tolerance to magnesium, calcium and acetate ions, effect of substrate concentration, acid distribution, and acid production; and (5) semi-continuous laboratory scale anaerobic digestion experiments to determine loading rates, conversion efficiencies, and other design data. 67 refs., 33 figs., 66 tabs.

  18. Effect of sodium chloride on growth, ion content, and hydrogen ion extrusion activity of sunflower and jojoba roots

    Microsoft Academic Search

    P. A. Burgos; M. Roldan; I. Agui; J. P. Donaire

    1993-01-01

    The effect of sodium chloride (NaCl) on growth, internal ion content, and proton release of sunflower (Helianthus annuus L. cv. Enano) and jojoba [Simmondsia chinensis (Link) Schneid.] roots was studied in order to understand the relationship between the above parameters and salt tolerance. The increase in sodium (Na) ions concentration and the decrease in calcium (Ca) ion concentration in sunflower

  19. CHLORIDE WASHER PERFORMACE TESTING

    SciTech Connect

    Coughlin, J; David Best, D; Robert Pierce, R

    2007-11-30

    Testing was performed to determine the chloride (Cl-) removal capabilities of the Savannah River National Laboratory (SRNL) designed and built Cl- washing equipment intended for HB-Line installation. The equipment to be deployed was tested using a cerium oxide (CeO2) based simulant in place of the 3013 plutonium oxide (PuO2) material. Two different simulant mixtures were included in this testing -- one having higher Cl- content than the other. The higher Cl- simulant was based on K-Area Interim Surveillance Inspection Program (KIS) material with Cl- content approximately equal to 70,000 ppm. The lower Cl- level simulant was comparable to KIS material containing approximately 8,000-ppm Cl- content. The performance testing results indicate that the washer is capable of reducing the Cl- content of both surrogates to below 200 ppm with three 1/2-liter washes of 0.1M sodium hydroxide (NaOH) solution. Larger wash volumes were used with similar results - all of the prescribed test parameters consistently reduced the Cl- content of the surrogate to a value below 200 ppm Cl- in the final washed surrogate material. The washer uses a 20-micron filter to retain the surrogate solids. Tests showed that 0.16-0.41% of the insoluble fraction of the starting mass passed through the 20-micron filter. The solids retention performance indicates that the fissile masses passing through the 20-micron filter should not exceed the waste acceptance criteria for discard in grout to TRU waste. It is recommended that additional testing be pursued for further verification and optimization purposes. It is likely that wash volumes smaller than those tested could still reduce the Cl- values to acceptable levels. Along with reduced wash volumes, reuse of the third wash volume (in the next run processed) should be tested as a wash solution minimization plan. A 67% reduction in the number of grouted paint pails could be realized if wash solution minimization testing returned acceptable results.

  20. Incidence of cancer among vinyl chloride and polyvinyl chloride workers.

    PubMed Central

    Heldaas, S S; Langård, S L; Andersen, A

    1984-01-01

    The results of a follow up study of the incidence of cancer and the mortality in a cohort of 454 male workers producing vinyl chloride and polyvinyl chloride are presented. The study population was restricted to employees with more than one year's work experience in the study plant between 1950 and 1969 and the cohort was followed up from 1953 to the end of 1979. Twenty three new cases of cancer were observed compared with 20.2 expected; one case of liver angiosarcoma was found. Five cases of lung cancer were found (2.8 expected) and four cases of malignant melanoma of the skin were observed (0.8 expected). The possibility of a causal relationship between exposure to vinyl chloride and the development of malignant melanomas is discussed. PMID:6691932

  1. Biomimetic remineralization of demineralized enamel with nano-complexes of phosphorylated chitosan and amorphous calcium phosphate.

    PubMed

    Zhang, Xu; Li, Yanqiu; Sun, Xiaoxi; Kishen, Anil; Deng, Xuliang; Yang, Xiaoping; Wang, Huajun; Cong, Changhong; Wang, Yinghui; Wu, Mingyao

    2014-12-01

    Remineralization of enamel plays a crucial role in the progression of carious process and the management of early caries lesion. Based on the influence of phosphorylated proteins in biomineralization, the objective of this study was to synthesize nano-complexes of phosphorylated chitosan and amorphous calcium phosphate (Pchi-ACP), and evaluate their ability to remineralize enamel subsurface lesions in vitro. Pchi was synthesized using a previously established chemical method. The biomimetic remineralizing solution containing nano-complexes of Pchi-ACP was prepared by adding CaCl2 and K2HPO4 into Pchi-ACP solution (0.5 % w/v) in sequence. The final concentrations of calcium and phosphate ions were 10 and 6 mM, respectively. The nano-complexes of Pchi-ACP were characterized by Fourier-transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). During testing the enamel lesions were treated with Pchi-ACP and fluoridated remineralizing solutions, respectively. The remineralizing of enamel lesions was examined with field emission electron microscope (FE-SEM) and Micro-CT. ACP was stabilized by Pchi to form nano-complexes that were soluble in water. The size of Pchi-ACP nano-complexes particles was determined to be less than 50 nm. XRD and SAED results confirmed their amorphous phases. FE-SEM and Micro-CT results showed that the remineralizing effect of Pchi-ACP on enamel lesions was similar to that of fluoride. However, the remineralizing rate of Pchi-ACP treatment was significantly higher than that of fluoride treatment (P < 0.05). This study highlighted the potential of nanoparticles functionalized with a natural analogue involved in biomineralization, to remineralize early enamel caries. PMID:25074834

  2. Effect of calcium on strawberry fruit flavonoid pathway gene expression and anthocyanin accumulation.

    PubMed

    Xu, Wenping; Peng, Hui; Yang, Tianbao; Whitaker, Bruce; Huang, Luhong; Sun, Jianghao; Chen, Pei

    2014-09-01

    Two diploid woodland strawberry (Fragaria vesca) inbred lines, Ruegen F7-4 (red fruit-bearing) and YW5AF7 (yellow fruit-bearing) were used to study the regulation of anthocyanin biosynthesis in fruit. Ruegen F7-4 fruit had similar total phenolics and anthocyanin contents to commercial octoploid (F. × ananassa) cultivar Seascape, while YW5AF7 exhibited relatively low total phenolics content and no anthocyanin accumulation. Foliar spray of CaCl2 boosted fruit total phenolics content, especially anthocyanins, by more than 20% in both Seascape and RF7-4. Expression levels of almost all the flavonoid pathway genes were comparable in Ruegen F7-4 and YW5AF7 green-stage fruit. However, at the turning and ripe stages, key anthocyanin structural genes, including flavanone 3-hydroxylase (F3H1), dihydroflavonol 4-reductase (DFR2), anthocyanidin synthase (ANS1), and UDP-glucosyltransferase (UGT1), were highly expressed in Ruegen F7-4 compared with YW5AF7 fruit. Calcium treatment further stimulated the expression of those genes in Ruegen F7-4 fruit. Anthocyanins isolated from petioles of YW5AF7 and Ruegen F-7 had the same HPLC-DAD profile, which differed from that of Ruegen F-7 fruit anthocyanins. All the anthocyanin structural genes except FvUGT1 were detected in petioles of YW5AF7 and Ruegen F-7. Taken together, these results indicate that the "yellow" gene in YW5AF7 is a fruit specific regulatory gene(s) for anthocyanin biosynthesis. Calcium can enhance accumulation of anthocyanins and total phenolics in fruit possibly via upregulation of anthocyanin structural genes. Our results also suggest that the anthocyanin biosynthesis machinery in petioles is different from that in fruit. PMID:25036468

  3. Disorders of Calcium Metabolism

    Microsoft Academic Search

    John F. O’Toole

    2011-01-01

    The genetic contribution to calcium metabolism is well recognized. Many of the proteins that contribute to calcium homeostasis through intestinal absorption, bone deposition and resorption, renal reabsorption and the molecules regulating these processes have been identified. Mutations in many of the genes coding for these proteins have been identified and often have clear clinical phenotypes. These mutations are generally rare

  4. Calcium signaling in neurodegeneration

    PubMed Central

    Marambaud, Philippe; Dreses-Werringloer, Ute; Vingtdeux, Valérie

    2009-01-01

    Calcium is a key signaling ion involved in many different intracellular and extracellular processes ranging from synaptic activity to cell-cell communication and adhesion. The exact definition at the molecular level of the versatility of this ion has made overwhelming progress in the past several years and has been extensively reviewed. In the brain, calcium is fundamental in the control of synaptic activity and memory formation, a process that leads to the activation of specific calcium-dependent signal transduction pathways and implicates key protein effectors, such as CaMKs, MAPK/ERKs, and CREB. Properly controlled homeostasis of calcium signaling not only supports normal brain physiology but also maintains neuronal integrity and long-term cell survival. Emerging knowledge indicates that calcium homeostasis is not only critical for cell physiology and health, but also, when deregulated, can lead to neurodegeneration via complex and diverse mechanisms involved in selective neuronal impairments and death. The identification of several modulators of calcium homeostasis, such as presenilins and CALHM1, as potential factors involved in the pathogenesis of Alzheimer's disease, provides strong support for a role of calcium in neurodegeneration. These observations represent an important step towards understanding the molecular mechanisms of calcium signaling disturbances observed in different brain diseases such as Alzheimer's, Parkinson's, and Huntington's diseases. PMID:19419557

  5. Calcium Nutrition in Adolescence

    Microsoft Academic Search

    Marta Mesías; Isabel Seiquer; M. Pilar Navarro

    2011-01-01

    Adolescence is an important period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. Calcium needs are elevated as a result of the intensive bone and muscular development and thus adequate calcium intake during growth is extremely important to reach the optimum peak bone mass and to protect against osteoporosis in the adult

  6. 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

  7. Calcium Transport in the Green Alga Mesotaenium caldariorum1

    PubMed Central

    Berkelman, Tom; Lagarias, J. Clark

    1990-01-01

    The subcellular localization and biochemical characterization of calcium transport were studied in the unicellular green alga Mesotaenium caldariorum. Membrane fractions prepared by osmotic lysis of Mesotaenium protoplasts exhibit high rates of ATP-dependent calcium uptake. Sucrose gradient centrifugation separates two pools of activity, which display specific activities for calcium transport as high as 15 nanomoles Ca2+ per minute per milligram of protein. Marker enzyme analysis shows that this dual distribution of calcium transport activity is similar to that of vanadate-insensitive ATPase and pyrophosphatase, activities considered to be associated with the tonoplast. Plasma membranes, endoplasmic reticulum vesicles, mitochondrial membranes, and thylakoids band at higher densities than either calcium transport fraction. Both pools of ATP-dependent calcium uptake contain two components which are not separable on sucrose gradients but can be distinguished on the basis of inhibitor sensitivity. One component is inhibited by nigericin or trimethyltin chloride (I50 values of 3 nanomolar and 4 micromolar, respectively), while the other component is vanadate sensitive (I50 of 25 micromolar). These results suggest that direct Ca2+ transport and Ca2+/H+ antiport activities are present in both sucrose gradient fractions. Images Figure 1 PMID:16667532

  8. Calcium homeostasis is altered in skeletal muscle of spontaneously hypertensive rats: cytofluorimetric and gene expression analysis.

    PubMed

    Liantonio, Antonella; Camerino, Giulia M; Scaramuzzi, Antonia; Cannone, Maria; Pierno, Sabata; De Bellis, Michela; Conte, Elena; Fraysse, Bodvael; Tricarico, Domenico; Conte Camerino, Diana

    2014-10-01

    Hypertension is often associated with skeletal muscle pathological conditions related to function and metabolism. The mechanisms underlying the development of these pathological conditions remain undefined. Because calcium homeostasis is a biomarker of muscle function, we assessed whether it is altered in hypertensive muscles. We measured resting intracellular calcium and store-operated calcium entry (SOCE) in fast- and slow-twitch muscle fibers from normotensive Wistar-Kyoto rats and spontaneously hypertensive rats (SHRs) by cytofluorimetric technique and determined the expression of SOCE gene machinery by real-time PCR. Hypertension caused a phenotype-dependent dysregulation of calcium homeostasis; the resting intracellular calcium of extensor digitorum longus and soleus muscles of SHRs were differently altered with respect to the related muscle of normotensive animals. In addition, soleus muscles of SHR showed reduced activity of the sarcoplasmic reticulum and decreased sarcolemmal calcium permeability at rest and after SOCE activation. Accordingly, we found an alteration of the expression levels of some SOCE components, such as stromal interaction molecule 1, calcium release-activated calcium modulator 1, and transient receptor potential canonical 1. The hypertension-induced alterations of calcium homeostasis in the soleus muscle of SHRs occurred with changes of some functional outcomes as excitability and resting chloride conductance. We provide suitable targets for therapeutic interventions aimed at counterbalancing muscle performance decline in hypertension, and propose the reported calcium-dependent parameters as indexes to predict how the antihypertensive drugs could influence muscle function. PMID:25084345

  9. Calcium ion binding to a soil fulvic acid using a donnan potential model

    USGS Publications Warehouse

    Marinsky, J.A.; Mathuthu, A.; Ephraim, J.H.; Reddy, M.M.

    1999-01-01

    Calcium ion binding to a soil fulvic acid (Armadale Bh Horizon) was evaluated over a range of calcium ion concentrations, from pH 3.8 to 7.3, using potentiometric titrations and calcium ion electrode measurements. Fulvic acid concentration was constant (100 milligrams per liter) and calcium ion concentration varied up to 8 X 10-4 moles per liter. Experiments discussed here included: (1) titrations of fulvic acid-calcium ion containing solutions with sodium hydroxide; and (2) titrations of fully neutralized fulvic acid with calcium chloride solutions. Apparent binding constants (expressed as the logarithm of the value, log ??app) vary with solution pH, calcium ion concentration, degree of acid dissociation, and ionic strength (from log ??app = 2.5 to 3.9) and are similar to those reported by others. Fulvic acid charge, and the associated Donnan Potential, influences calcium ion-fulvic acid ion pair formation. A Donnan Potential corrrection term allowed calculation of intrinsic calcium ion-fulvic acid binding constants. Intrinsic binding constants vary from 1.2 to 2.5 (the average value is about log??= 1.6) and are similar to, but somewhat higher than, stability constants for calcium ion-carboxylic acid monodentate complexes. ?? by Oldenbourg Wissenschaftsverlag, Mu??nchen.

  10. Alternative technique for calcium phosphate coating on titanium alloy implants.

    PubMed

    Le, Van Quang; Pourroy, Geneviève; Cochis, Andrea; Rimondini, Lia; Abdel-Fattah, Wafa I; Mohammed, Hadeer I; Carradò, Adele

    2014-01-01

    As an alternative technique for calcium phosphate coating on titanium alloys, we propose to functionalize the metal surface with anionic bath containing chlorides of palladium or silver as activators. This new deposition route has several advantages such as controlled conditions, applicability to complex shapes, no adverse effect of heating, and cost effectiveness. A mixture of hydroxyapatite and calcium phosphate hydrate is deposited on the surface of Ti-6Al-4V. Calcium phosphate coating is built faster compared with the one by Simulated Body Fluid. Cell morphology and density are comparable to the control one; and the results prove no toxic compound is released into the medium during the previous seven days of immersion. Moreover, the cell viability is comparable with cells cultivated with the virgin medium. These experimental treatments allowed producing cytocompatible materials potentially applicable to manufacture implantable devices for orthopedic and oral surgeries. PMID:24646569

  11. Calcium-43 chemical shift and electric field gradient tensor interplay: a sensitive probe of structure, polymorphism, and hydration.

    PubMed

    Widdifield, Cory M; Moudrakovski, Igor; Bryce, David L

    2014-07-14

    Calcium is the 5th most abundant element on earth, and is found in numerous biological tissues, proteins, materials, and increasingly in catalysts. However, due to a number of unfavourable nuclear properties, such as a low magnetogyric ratio, very low natural abundance, and its nuclear electric quadrupole moment, development of solid-state (43)Ca NMR has been constrained relative to similar nuclides. In this study, 12 commonly-available calcium compounds are analyzed via(43)Ca solid-state NMR and the information which may be obtained by the measurement of both the (43)Ca electric field gradient (EFG) and chemical shift tensors (the latter of which are extremely rare with only a handful of literature examples) is discussed. Combined with density functional theory (DFT) computations, this 'tensor interplay' is, for the first time for (43)Ca, illustrated to be diagnostic in distinguishing polymorphs (e.g., calcium formate), and the degree of hydration (e.g., CaCl2·2H2O and calcium tartrate tetrahydrate). For Ca(OH)2, we outline the first example of (1)H to (43)Ca cross-polarization on a sample at natural abundance in (43)Ca. Using prior knowledge of the relationship between the isotropic calcium chemical shift and the calcium quadrupolar coupling constant (CQ) with coordination number, we postulate the coordination number in a sample of calcium levulinate dihydrate, which does not have a known crystal structure. Natural samples of CaCO3 (aragonite polymorph) are used to show that the synthetic structure is present in nature. Gauge-including projector augmented-wave (GIPAW) DFT computations using accepted crystal structures for many of these systems generally result in calculated NMR tensor parameters which are in very good agreement with the experimental observations. This combination of (43)Ca NMR measurements with GIPAW DFT ultimately allows us to establish clear correlations between various solid-state (43)Ca NMR observables and selected structural parameters, such as unit cell dimensions and average Ca-O bond distances. PMID:24874995

  12. Interactions of Calcium, pH, Temperature, and Chymosin During Milk Coagulation[1] and [2

    Microsoft Academic Search

    L. M. Okigbo; G. H. Richardson; R. J. Brown; C. A. Ernstrom

    1985-01-01

    Holstein milk samples with good and poor chymosin-coagulation characteristics were coagulated in the Formagraph using different combinations of five levels of chymosin, three pH, and three tempera- tures in the presence and absence of .02% added calcium chloride. AII the main factors significantly altered both coagulation time and curd firmness. Multiple comparisons of mean coagulation times showed that lower concentrations

  13. Calcium-induced displacement of membrane-associated particles upon aggregation of chromaffin granules.

    PubMed

    Schober, R; Nitsch, C; Rinne, U; Morris, S J

    1977-02-01

    Isolated chromaffin granules incubated in 10 millimolar calcium chloride aggregated, forming contact sites with a pentalaminar membrane structure. These circular attachment sites were free of membrane-associated particles, which accumulated at the periphery. Incubation in 20 millimolar ethylenediaminetetraacetic acid reversed these changes, which are regarded as initial events in the membrane fusion reaction. PMID:835010

  14. Sodium-calcium ion exchange in the weathering of shales: Implications for global weathering budgets

    Microsoft Academic Search

    T. E. Cerling; B. L. Pederson; K. L. Von Damm

    1989-01-01

    Unpolluted rivers and streams that drain marine shales show an excess of sodium compared to chloride and a deficiency of calcium and magnesium compared to sulfate and alkalinity. This is due in part to cation exchange of sodium for divalent cations on clay minerals. Consideration of the global weathering budget suggest that up to 34% of the sodium in the

  15. The Obesity-Related Peptide Leptin Sensitizes Cardiac Mitochondria to Calcium-Induced Permeability Transition Pore Opening and Apoptosis

    PubMed Central

    Martinez-Abundis, Eduardo; Rajapurohitam, Venkatesh; Haist, James V.; Gan, Xiaohong T.; Karmazyn, Morris

    2012-01-01

    The obesity-related 16 kDa peptide leptin is synthesized primarily in white adipocytes although its production has been reported in other tissues including the heart. There is emerging evidence that leptin may contribute to cardiac pathology especially that related to myocardial remodelling and heart failure. In view of the importance of mitochondria to these processes, the goal of the present study is to determine the effect of leptin on mitochondria permeability transition pore opening and the potential consequence in terms of development of apoptosis. Experiments were performed using neonatal rat ventricular myocytes exposed to 3.1 nM (50 ng/ml) leptin for 24 hours. Mitochondrial transition pore opening was analyzed as the capacity of mitochondria to retain the dye calcein-AM in presence of 200 µM CaCl2. Leptin significantly increased pore opening although the effect was markedly more pronounced in digitonin-permeabilized myocytes in the presence of calcium with both effects prevented by the transition pore inhibitor sanglifehrin A. These effects were associated with increased apoptosis as evidenced by increased TUNEL staining and caspase 3 activity, both of which were prevented by the transition pore inhibitor sanglifehrin A. Leptin enhanced Stat3 activation whereas a Stat 3 inhibitor peptide prevented leptin-induced mitochondrial transition pore opening as well as the hypertrophic and pro-apoptotic effects of the peptide. Inhibition of the RhoA/ROCK pathway prevented the hypertrophic response to leptin but had no effect on increased pore opening following leptin administration. We conclude that leptin can enhance calcium-mediated, Stat3-dependent pro-apoptotic effects as a result of increased mitochondrial transition pore opening and independently of its hypertrophic actions. Leptin may therefore contribute to mitochondrial dysfunction and the development of apoptosis in the diseased myocardium particularly under conditions of excessive intracellular calcium accumulation. PMID:22848545

  16. A9C sensitive Cl? - accumulation in A. thaliana root cells during salt stress is controlled by internal and external calcium

    PubMed Central

    Saleh, Livia; Plieth, Christoph

    2013-01-01

    The involvement of chloride in salt stress symptoms and salt tolerance mechanisms in plants has been less investigated in the past. Therefore, we studied the salt-induced chloride influx in Arabidopsis expressing the GFP-based anion indicator Clomeleon. High salt concentrations induce two phases of chloride influx. The fast kinetic phase is likely caused by membrane depolarization, and is assumed to be mediated by channels. This is followed by a slower "saturation" phase, where chloride is accumulated in the cytoplasm. Both phases of chloride uptake are dependent on the presence of external calcium. In general: with high [Ca2+] less chloride is accumulated in the cytoplasm. Surprisingly, also the internal calcium availability has an impact on chloride transport. A complete block of the second phase of chloride influx is achieved by the anion channel blocker A9C and trivalent cations (La3+, Gd3+, and Al3+). Other channel blockers and diuretics were found to inhibit the process partially. The results suggest that several transporter species are involved here, including electroneutral cation-chloride-cotransporters, and a part of chloride possibly enters the cells through cation channels after salt application. PMID:23603974

  17. Metal lanolin fatty acid as novel thermal stabilizers for rigid poly(vinyl chloride)

    Microsoft Academic Search

    Yong GUO; Yuying ZHENG; Shangchang QIU; Anran ZENG; Baoming LI

    2011-01-01

    The synergistic stabilization effect of different metal lanolin fatty acids as natural-based thermal stabilizers for poly(vinyl chloride) (PVC) including calcium lanolin fatty acid (Calan2), zinc lanolin fatty acid (Znlan2) and lanthanum lanolin fatty acid (Lalan3) were studied through Congo red testing, color measurements, FTIR analyses and thermal behavior in this paper. The results showed that Lalan3\\/Calan2\\/Znlan2 stabilizers exhibited more excellent

  18. Solubility of some alkali and alkaline earth chlorides in water at moderate temperatures

    USGS Publications Warehouse

    Clynne, M.A.; Potter, R.W., II

    1979-01-01

    Solubilities for the binary systems, salt-H2O, of the chlorides of lithium, rubidium, cesium, magnesium, calcium, strontium, and barium from near 0??C to the saturated boiling point are reported. The experimental data and coefficients of an equation for a smoothed curve describing each system are listed in the tables. The data are improvements on those previously reported in the literature, having a precision on the average of ??0.09%.

  19. Partial molar volumes of uni-univalent electrolytes in methanol + water; 1: Lithium chloride, sodium chloride, and potassium chloride

    SciTech Connect

    Takenaka, Nobuo; Takemura, Takeshi; Sakurai, Masao (Hokkaido Univ., Sapporo (Japan). Research Inst. for Electronic Science)

    1994-04-01

    Densities of methanol + water + lithium chloride, + sodium chloride, and + potassium chloride were measured at 15, 25, 35, and 45 C. The apparent molar volumes of the electrolytes in these mixtures were calculated, and the apparent molar volumes at infinite dilution, the partial molar volumes, and partial molar thermal expansivities were evaluated.

  20. Effects of low chloride intake on performance, clinical characteristics, and chloride, sodium, potassium, and nitrogen metabolism in dairy calves.

    PubMed

    Burkhalter, D L; Neathery, M W; Miller, W J; Whitlock, R H; Allen, J C

    1979-12-01

    Young male Holstein calves were fed either a control (.5% chloride) or a low-chloride (.038% chloride) practical diet for 7 wk. Both groups received low-chloride (.00038% chloride) well water. Feeding the low-chloride diet did not produce definite clinical symptoms of chloride deficiency. Neither body weight gains, feed intake, feed digestibility, nor body retention of chloride, sodium, potassium, or nitrogen were effected adversely. Although the chloride intake of the low-chloride calves was only one-sixteenth that of controls, body chloride retention was similar for the two groups. The similar retention of body chloride was due to effective homeostatic mechanisms in which urinary chloride excretion was reduced by 95% in the low-chloride calves. Low-chloride calves consumed more water and excreted more urine than control calves. Although the exact minimum chloride requirement for growth in calves was not established, .038% chloride was adequate for normal growth for the 7 wk. PMID:541461

  1. Study of chloride ion migration in reinforced concrete under cathodic protection. Final report

    SciTech Connect

    Orlova, N.V.; Westall, J.C.; Rehani, M.; Koretsky, M.D.

    1999-09-01

    The migration of chloride ions in concrete with steel reinforcement was investigated. Mortar blocks (15 cm x 15 cm x 17 cm) of various composition (water to cement ratio, chloride ion content) were cast with an iron mesh cathode imbedded along one face and a thermally sprayed zinc anode applied to the opposite face. Current densities of 0.033 and 0.066 A (sq m) were applied to the blocks over a period of one year at constant temperature and humidity. The zinc face was covered with a pond of saturated calcium hydroxide to prevent polarization of the zinc-concrete interface. Over the course of polarization, potential vs. time curves were recorded and samples of mortar were extracted for determination of chloride concentration.

  2. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures...Alternatively, hydrogen chloride formed by the burning of hydrogen in chlorine is dissolved in water and then reacted with...

  3. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures...Alternatively, hydrogen chloride formed by the burning of hydrogen in chlorine is dissolved in water and then reacted with...

  4. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures...Alternatively, hydrogen chloride formed by the burning of hydrogen in chlorine is dissolved in water and then reacted with...

  5. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures...Alternatively, hydrogen chloride formed by the burning of hydrogen in chlorine is dissolved in water and then reacted with...

  6. Cystic Fibrosis (CF): Chloride Sweat Test

    MedlinePLUS

    ... Sports: Keeping Kids Safe Concussions: What to Know Cystic Fibrosis (CF) Chloride Sweat Test KidsHealth > Parents > General Health > Sick Kids > Cystic Fibrosis (CF) Chloride Sweat Test Print A A A ...

  7. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  8. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  9. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely used for color retention in...

  10. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  11. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 582.3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  12. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely used for color retention in...

  13. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely used for color retention in...

  14. CHEMILUMINESCENT MONITOR FOR VINYL CHLORIDE

    EPA Science Inventory

    A monitor for vinyl chloride monomer (VCM) in ambient air was constructed using commercially available components of a gas chromatograph (GC) coupled with a chemiluminescence ozone analyzer slightly modified to make it suitable for use as a GC detector. The specificity for VCM is...

  15. Chloride secretagogues stimulate inositol phosphate formation in shark rectal gland tubules cultured in suspension

    SciTech Connect

    Ecay, T.W.; Valentich, J.D. (Univ. of Texas Medical School, Houston (USA))

    1991-03-01

    Neuroendocrine activation of transepithelial chloride secretion by shark rectal gland cells is associated with increases in cellular cAMP, cGMP, and free calcium concentrations. We report here on the effects of several chloride secretagogues on inositol phosphate formation in cultured rectal gland tubules. Vasoactive intestinal peptide (VIP), atriopeptin (AP), and ionomycin increase the total inositol phosphate levels of cultured tubules, as measured by ion exchange chromatography. Forskolin, a potent chloride secretagogue, has no effect on inositol phosphate formation. The uptake of {sup 3}H-myo-inositol into phospholipids is very slow, preventing the detection of increased levels of inositol trisphosphate. However, significant increases in inositol monophosphate (IP1) and inositol biphosphate (IP2) were measured. The time course of VIP- and AP-stimulated IP1 and IP2 formation is similar to the effects of these agents on the short-circuit current responses of rectal gland monolayer cultures. In addition, aluminum fluoride, an artificial activator of guanine nucleotide-binding proteins, stimulates IP1 and IP2 formation. We conclude that rectal gland cells contain VIP and AP receptors coupled to the activation of phospholipase C. Coupling may be mediated by G-proteins. Receptor-stimulated increases in inositol phospholipid metabolism is one mechanism leading to increased intracellular free calcium concentrations, an important regulatory event in the activation of transepithelial chloride secretion by shark rectal gland epithelial cells.

  16. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M. (Stanford, CA); Muller, Jochen A. (Baltimore, MD); Rosner, Bettina M. (Berlin, DE); Von Abendroth, Gregory (Nannhein, DE); Meshulam-Simon, Galit (Los Altos, CA); McCarty, Perry L (Stanford, CA)

    2011-11-22

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  17. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Mannheim, DE; Meshulam-Simon, Galit [Los Angeles, CA; McCarty, Perry L [Stanford, CA

    2014-02-11

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  18. Developing chloride resisting concrete using PFA

    Microsoft Academic Search

    R. K. Dhir; M. A. K. El-Mohr; T. D. Dyer

    1997-01-01

    PFA concrete mixes were designed to optimise resistance to chloride ingress. Chloride binding capacity, intrinsic permeability and their concomitant influence on the coefficient of chloride diffusion have been investigated. PFA replacements up to 67% and exposure concentrations of 0.1, 0.5, 1.0 and 5.0 mole\\/litre were used. Chloride binding capacity was found to increase with increasing PFA replacement up to 50%

  19. Rapid Low Temperature-Induced Stomatal Closure Occurs in Cold-Tolerant Commelina communis Leaves But Not in Cold-Sensitive Tobacco Leaves, via a Mechanism That Involves Apoplastic Calcium But Not Abscisic Acid1

    PubMed Central

    Wilkinson, Sally; Clephan, Alison Lee; Davies, William John

    2001-01-01

    Commelina communis stomata closed within 1 h of transferring intact plants from 27°C to 7°C, whereas tobacco (Nicotiana rustica) stomata did not until the leaves wilted. Abscisic acid (ABA) did not mediate cold-induced C. communis stomatal closure: At low temperatures, bulk leaf ABA did not increase; ABA did not preferentially accumulate in the epidermis; its flux into detached leaves was lower; its release from isolated epidermis was not greater; and stomata in epidermal strips were less sensitive to exogenous ABA. Stomata of both species in epidermal strips on large volumes of cold KCl failed to close unless calcium was supplied. Therefore, the following cannot be triggers for cold-induced stomatal closure in C. communis: direct effects of temperature on guard or epidermal cells, long-distance signals, and effects of temperature on photosynthesis. Low temperature increased stomatal sensitivity to external CaCl2 by 50% in C. communis but only by 20% in tobacco. C. communis stomata were 300- to 1,000-fold more sensitive to calcium at low temperature than tobacco stomata, but tobacco epidermis only released 13.6-fold more calcium into bathing solutions than C. communis. Stomata in C. communis epidermis incubated on ever-decreasing volumes of cold calcium-free KCl closed on the lowest volume (0.2 cm3) because the epidermal apoplast contained enough calcium to mediate closure if this was not over diluted. We propose that the basis of cold-induced stomatal closure exhibited by intact C. communis leaves is increased apoplastic calcium uptake by guard cells. Such responses do not occur in chill-sensitive tobacco leaves. PMID:11500555

  20. Electrochemical chloride removal from concrete prisms containing chloride penetrated from sea water

    Microsoft Academic Search

    Rob B. Polder

    1996-01-01

    Electrochemical chloride removal tests were carried out in the laboratory of reinforced concrete prisms containing chloride due to 16 years' submersion in the North Sea. After 39 days of treatment using current densities of about 1 and 4 Am2 steel surface, about 40% to 70% of the initial chloride was removed from the concrete on average. The chloride contents close

  1. Analysis of the isotope effect in the hydrogen exchange reaction between pyridinium chloride and hydrogen chloride

    Microsoft Academic Search

    J. Szydlowski; M. Zielinski

    1979-01-01

    Hydrogen isotope exchange between pyridinium chloride and gaseous hydrogen chloride has been studied both experimentally and theoretically over the temperature range of 273 to 353 K. The experimental fractionation factor obtained shows some dependence on the composition of the substrates. This phenomenon can be accounted for by specific interactions in pyridinium chloride + hydrogen chloride system. The calculated fractionation factor

  2. Calcium, Bone, and Life

    Microsoft Academic Search

    Robert P. Heaney

    \\u000a Calcium is a divalent mineral cation that functions as an intracellular messenger in virtually all life forms. In multicellular\\u000a organisms it functions also as an integrator tying body systems together, and in land-living vertebrates it provides the principal\\u000a mineral component of the endoskeleton (bone). Calcium cannot be synthesized and must be ingested, first to build an adult\\u000a skeleton and then

  3. Worker exposure to vinyl chloride and poly(vinyl chloride).

    PubMed Central

    Jones, J H

    1981-01-01

    The National Institute for Occupational Safety and Health (NIOSH) in early 1974 began industrial hygiene studies of vinyl chloride exposed workers. Three VC monomer plants, three VC polymerization plants, and seven PVC fabrication plants were surveyed. V polymerization plant workers and workers in one job category in VC monomer plants were exposed to average levels above 1 ppm. The highest average exposure was 22 ppm. NIOSH health hazard evaluation studies since these initial surveys have primarily shown nondetectable levels of vinyl chloride. A NIOSH control technology study in 1977 showed that exposure levels in VC polymerization plants had been drastically reduced but exposure levels above 1 ppm were still found in several cases. PMID:7333231

  4. An XAFS Study of Tantalum Chloride in the Ionic Liquid 1-ethyl-3-methyl Imidazolium Chloride/ aluminum Chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Tantalum chloride was studied with extended X-ray absorption fine structure spectroscopy (XAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride ionic liquids (ILs). Anhydrous Ta2Cl10 is more soluble in the basic solution than in the acidic solution and the X-ray absorption data shows that the coordination shell of chlorides around the tantalum is larger in the basic solution. In the acidic solution, tantalum has five chlorides in its coordination shell while in the basic solution; the tantalum is coordinated by seven chlorides. This indicates that the Lewis acidity of the tantalum chloride causes the Ta to coordinate differently in the acidic and the basic solutions.

  5. Factors influencing electrochemical removal of chloride from concrete

    Microsoft Academic Search

    P. R. W. Vassie

    1996-01-01

    Electrochemical chloride removal was studied using prisms made from concrete containing various levels of chlorides derived from sodium chloride added during mixing. The amount of chloride removed during the treatment was assessed by analysing the anolyte. Chloride removal increased with increasing applied potential, number of reinforcing bars at a particular depth and initial chloride content of the concrete. A greater

  6. Biphasic release of indomethacin from HPMC\\/pectin\\/calcium matrix tablet: II. Influencing variables, stability and pharmacokinetics in dogs

    Microsoft Academic Search

    Baojian Wu; Daoyin Deng; Yi Lu; Wei Wu

    2008-01-01

    The pectin\\/calcium interaction, which is the basis for biphasic release of indomethacin from the HPMC\\/pectin\\/calcium chloride matrix tablet, is susceptible to influence of a variety of variables that is supposed to be encountered by the oral route. In this study, the effect of influencing variables on biphasic release characteristics, the stability and the pharmacokinetics of the hybrid matrix tablet were

  7. Effects of Low Chloride Intake on Performance, Clinical Characteristics, and Chloride, Sodium, Potassium, and Nitrogen Metabolism in Dairy Calves1

    Microsoft Academic Search

    D. L. Burkhalter; M. W. Neathery; W. J. Miller; R. H. Whitlock; J. C. Allen

    1979-01-01

    Young male Holstein calves were fed either a control (.5% chloride) or a low-chloride (.038% chloride) practical diet for 7 wk. Both groups received low-chloride (.00038% chloride) well water. Feeding the low-chloride diet did not produce definite clinical symptoms of chloride deficiency. Neither body weight gains, feed intake, feed digestibility, nor body retention of chloride, sodium, potassium, or nitrogen were

  8. Developing chloride resisting concrete using PFA

    SciTech Connect

    Dhir, R.K.; El-Mohr, M.A.K.; Dyer, T.D. [Univ. of Dundee (United Kingdom). Dept. of Civil Engineering] [Univ. of Dundee (United Kingdom). Dept. of Civil Engineering

    1997-11-01

    PFA concrete mixes were designed to optimize resistance to chloride ingress. Chloride binding capacity, intrinsic permeability and their concomitant influence on the coefficient of chloride diffusion have been investigated. PFA replacements up to 67% and exposure concentrations of 0.1, 0.5, 1.0 and 5.0 mole/liter were used. Chloride binding capacity was found to increase with increasing PFA replacement up to 50% and to then decline. It increased with chloride exposure concentration as well as water/binder ratio. The coefficient of chloride diffusion of concrete samples was found to be dependent on both the intrinsic permeability of the concrete and the ability of its cement matrix to bind chlorides.

  9. Study of acute pharmacologic effects of prolactin on calcium and water transport in the rat colon by an in vivo perfusion technique.

    PubMed

    Krishnamra, N; Ousingsawat, J; Limlomwongse, L

    2001-05-01

    We investigated the acute effect of intraperitoneally administered prolactin on calcium and water transport in colon of sexually mature female Wistar rats using an in vivo perfusion technique. Test solution containing (in mM) NaCl, 100; KCl, 4.7; MgSO4, 1.2; CaCl2, 20; D-glucose, 11; sodium ferrocyanide (Na4Fe(CN)6), an index of net water transport, 20; and 0.7 (microCi 45CaCl2 (1 Ci = 37 GBq) was perfused througth the 8-cm colonic loop for 60 min at perfusion rates of 0.5 or 1.0 mL x min(-1). Calcium and water transport was also studied under a no flow condition to stimulate the condition often found in the colon by in vivo ligated colonic loop for 30 min. Control results showed no correlation between calcium transport and water flux. Flow of luminal solution at 0.5 and 1.0 mL x min(-1) was found to reverse net calcium absorption from 0.04+/-0.01 nmol x g(-1) dry weight x h(-1) to net calcium secretion of 0.04+/-0.04 and 0.9+/-0.02 nmol x g(-1) dry weight x h(-1), respectively. Neither 0.4, 0.6, nor 1.0 mg x kg(-1) prolactin had any effect on calcium fluxes in the colon. On the other hand, at a perfusion rate of 1 mL x min(-1), 0.4 mg x kg(-1) prolactin significantly decreased net water absorption from 3.86+/-0.90 to 0.88+/-0.64 mL x g(-1) dry weight x h(-1) (P < 0.001), and the higher doses of 0.6 and 1.0 mg x kg(-1) prolactin reversed net water absorption to net water secretion of 2.20+/-0.63 and 2.33+/-0.89 mL x g(-1) dry weight x h(-1), respectively (P < 0.001). The stimulatory effect of prolactin on water transport was completely abolished by reducing the perfusion rate from 1.0 mL x min(-1) to zero. The stimulatory effect of prolactin on water secretion at perfusion rate of 1.0 mL x min(-1) was also abolished when luminal [Na+] was reduced from 180 to 80 mM. We concluded that, unlike in the small intestine, calcium fluxes in the colon are not related to water transport and did not respond at all to prolactin. Water transport, on the other hand, was reversed from net absorption to secretion by prolactin. We propose that this prolactin-induced water secretion is probably mediated by recycling of luminal sodium in the vicinity of tight junctions. PMID:11405245

  10. Hydrostatic Pressure–Induced Release of Stored Calcium in Cultured Rat Optic Nerve Head Astrocytes

    PubMed Central

    Mandal, Amritlal; Delamere, Nicholas A.

    2010-01-01

    Purpose. Elevated intraocular pressure is associated with glaucomatous optic nerve damage. Other investigators have shown functional changes in optic nerve head astrocytes subjected to elevated hydrostatic pressure (HP) for 1 to 5 days. Recently, the authors reported ERK1/2, p90RSK and NHE1 phosphorylation after 2 hours. Here they examine calcium responses at the onset of HP to determine what precedes ERK1/2 phosphorylation. Methods. Cytoplasmic calcium concentration ([Ca2+]i) was measured in cultured rat optic nerve astrocytes loaded with fura-2. The cells were placed in a closed imaging chamber and subjected to an HP increase of 15 mm Hg. Protein phosphorylation was detected by Western blot analysis. Results. The increase of HP caused an immediate slow increase in [Ca2+]i. The response persisted in calcium-free solution and when nickel chloride (4 mM) was added to suppress channel-mediated calcium entry. Previous depletion of the ER calcium stores by cyclopiazonic acid abolished the HP-induced calcium level increase. The HP-induced increase persisted in cells exposed to xestospongin C, an inhibitor of IP3R-mediated calcium release. In contrast, ryanodine receptor (RyR) antagonist ruthenium red (10 ?M) or dantrolene (25 ?M) inhibited the HP-induced calcium increase. The HP-induced calcium increase was abolished when ryanodine-sensitive calcium stores were pre-depleted with caffeine (3 mM). HP caused ERK1/2 phosphorylation. The magnitude of the ERK1/2 phosphorylation response was reduced by ruthenium red and dantrolene. Conclusions. Increasing HP causes calcium release from a ryanodine-sensitive cytoplasmic store and subsequent ERK1/2 activation. Calcium store release appears to be a required early step in the initial astrocyte response to an HP increase. PMID:20071675

  11. Blood calcium dynamics after prophylactic treatment of subclinical hypocalcemia with oral or intravenous calcium.

    PubMed

    Blanc, C D; Van der List, M; Aly, S S; Rossow, H A; Silva-del-Río, N

    2014-11-01

    Total serum Ca dynamics and urine pH levels were evaluated after prophylactic treatment of subclinical hypocalcemia after parturition in 33 multiparous Jersey × Holstein crossbreed cows. Cows were blocked according to their calcemic status at the time of treatment [normocalcemic (8.0-9.9 mg/dL; n = 15) or hypocalcemic (5.0-7.9 mg/dL; n = 18)] and randomly assigned to 1 of 3 treatments: control [no Ca supplementation (n = 11)]; intravenous Ca [Ca-IV (n = 11), 500 mL of 23% calcium gluconate (10.7 g of Ca and 17.5 g of boric acid as a solubilizing agent; Durvet, Blue Springs, MO)]; or oral Ca [Ca-Oral (n = 11), 1 oral bolus (Bovikalc bolus, Boehringer Ingelheim, St. Joseph, MO) containing CaCl2 and CaSO4 (43 g of Ca) 2 times 12h apart]. Total serum Ca levels were evaluated at 0, 1, 2, 4, 8, 12, 16, 20, 24, 36, and 48 h, and urine pH was evaluated at 0, 1, 12, 24, 36, and 4 8h after treatment initiation. Total serum Ca levels were higher for Ca-IV than for control and Ca-Oral cows at 1, 2, and 4h after treatment initiation, but lower than Ca-Oral cows at 20, 24, and 36 h and lower than control cows at 36 and 48 h. At 1h after treatment initiation, when serum Ca levels for Ca-IV cows peaked (11.4 mg/dL), a greater proportion of Ca-IV (n = 8) cows had total serum Ca levels >10mg/dL than control (n = 0) and Ca-Oral (n = 1) cows. At 24h after treatment initiation, when Ca-IV cows reached the total serum Ca nadir (6.4 mg/dL), a greater proportion of Ca-IV (n = 10) cows had serum Ca levels <8 mg/dL than control (n = 5) and Ca-Oral (n = 2) cows. Treatment, time, and treatment × time interaction were significant for urine pH. Mean urine pH was lower for Ca-Oral cows (6.69) than for control (7.52) and Ca-IV (7.19) cows. Urine pH levels at 1h after treatment were lower for Ca-IV cows compared with both control and Ca-Oral cows, a finding likely associated with the iatrogenic administration of boric acid added as a solubilizing agent of the intravenous Ca solution used. At 12, 24, and 36 h, urine pH levels were lower for Ca-Oral cows compared with both control and Ca-IV cows. This was expected because the oral Ca supplementation used (Bovikalc) is designed as an acidifying agent. Wide fluctuations in blood Ca were observed after prophylactic intravenous Ca supplementation. The implications for milk production and animal health, if any, of these transient changes in total serum Ca have yet to be evaluated. PMID:25200776

  12. Impact of sulfate and chloride on sediment phosphorus release in the Yangtze Estuary Reservoir, China.

    PubMed

    Jin, Xiaodan; He, Yiliang; Zhang, Bo; Hassan, Younas; George, Kirumba

    2013-01-01

    The impact of sulfate (SO4(2-)) and chloride (Cl(-)) on phosphorus (P) release from sediment in the drinking water reservoir of Yangtze River Estuary was studied systematically. A significant correlation between sodium (Na(+)), Cl(-), SO4(2-) and total P was found, suggesting that P was directly or indirectly associated with these ions. SO4(2-) and Cl(-) were important factors that had an impact on P release from the sediment. The results showed that both sulfate and chloride enhanced phosphorus release from sediment. In the sulfate treatment, the decrease of organic phosphorus (OP) suggested that the mineralization of OP enhanced P release from sediment. Phosphonate was the main factor affecting the P release under sulfate condition. In chloride treatment, the sediment composition of iron (Fe), aluminum (Al), calcium (Ca) and magnesium (Mg) increased. The P fractions of Fe/Al-P, Ca-P and OP in sediment also increased. However, the increase of P was unstable after chloride treatment and was easy to release under disturbance. In this study, it was observed that sulfate and chloride could increase the risk of eutrophication in the Yangtze River Estuary drinking water reservoir. PMID:23579829

  13. The role of magnesium and calcium ions in the glucose dehydrogenase activity of Klebsiella pneumoniae NCTC 418

    Microsoft Academic Search

    Ed T. Buurman; José L. Boiardi; M. Joost Teixeira de Mattos; Oense M. Neijssel

    1990-01-01

    Magnesium-limited chemostat cultures of Klebsiella pneumoniae NCTC 418 with 20 µM CaCl2 in the medium showed a low rate of gluconate plus 2-ketogluconate production relative to potassium- or phosphate-limited cultures. However, when the medium concentration of CaCl2 was increased to 1 mM, the glucose dehydrogenase (GDH) activities also increased and became similar to those observed in potassium- or phosphate limited

  14. 21 CFR 172.410 - Calcium silicate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Drugs 3 2014-04-01 2014-04-01 false Calcium silicate. 172.410 Section 172.410 Food...HUMAN CONSUMPTION Anticaking Agents § 172.410 Calcium silicate. Calcium silicate, including synthetic calcium...

  15. 21 CFR 172.410 - Calcium silicate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Drugs 3 2012-04-01 2012-04-01 false Calcium silicate. 172.410 Section 172.410 Food...HUMAN CONSUMPTION Anticaking Agents § 172.410 Calcium silicate. Calcium silicate, including synthetic calcium...

  16. 21 CFR 172.410 - Calcium silicate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Drugs 3 2013-04-01 2013-04-01 false Calcium silicate. 172.410 Section 172.410 Food...HUMAN CONSUMPTION Anticaking Agents § 172.410 Calcium silicate. Calcium silicate, including synthetic calcium...

  17. 21 CFR 172.410 - Calcium silicate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Drugs 3 2011-04-01 2011-04-01 false Calcium silicate. 172.410 Section 172.410 Food...HUMAN CONSUMPTION Anticaking Agents § 172.410 Calcium silicate. Calcium silicate, including synthetic calcium...

  18. Morphological evolution of precipitates during transformation of amorphous calcium phosphate into octacalcium phosphate in relation to role of intermediate phase

    NASA Astrophysics Data System (ADS)

    Sugiura, Yuki; Onuma, Kazuo; Kimura, Yuki; Miura, Hitoshi; Tsukamoto, Katsuo

    2011-10-01

    Nucleation of amorphous calcium phosphate (ACP) and its phase transformation with a decrease in solution pH were investigated at a constant temperature of 32 °C. A solution containing a mixture of CaCl 2 and KH 2PO 4 was prepared (initial pH=7.7), and a drop was sampled at a constant interval to observe the morphological evolution of the precipitates that formed in the solution. A gel-like solution structure formed immediately after mixing and contained a small amount of sea-urchin-like ACP spherulites (3-20 ?m in size). These spherulites consisted of 1.5-10-?m-long flexible needles that formed simultaneously with numerous ACP spherical particles. They first transformed into ?-tri calcium phosphate-like material (called "pseudo ?-TCP") and then into single crystals of octacalcium phosphate (OCP) without dissolution. The flexible needles in the spherulites changed into blade springs, then into flexible plates, and finally into rigid plates during the transformation. The OCP structure appeared in the pseudo ?-TCP plates and gradually substituted for the ?-TCP structure over time. The macroscopic spherulite morphology of the initial ACP remained unchanged during the phase transformation, suggesting that OCP is a pseudomorph of ACP. This feature was observed only when the ACP spherulites formed in the initial solution. Fiber-like aggregates consisting of ?-TCP single crystals nucleated around the ACP spherical particles and grew over time. They survived until the final stage of the reaction, and OCP polycrystals formed in the mixture of ?-TCP and ACP spheres. The OCP polycrystals gradually substituted for the ACP spheres without phase transformation of ?-TCP into OCP.

  19. Changes in Sodium, Calcium, and Magnesium Ion Concentrations That Inhibit Geobacillus Biofilms Have No Effect on Anoxybacillus flavithermus Biofilms.

    PubMed

    Somerton, B; Lindsay, D; Palmer, J; Brooks, J; Flint, S

    2015-08-01

    This study investigated the effects of varied sodium, calcium, and magnesium concentrations in specialty milk formulations on biofilm formation by Geobacillus spp. and Anoxybacillus flavithermus. The numbers of attached viable cells (log CFU per square centimeter) after 6 to 18 h of biofilm formation by three dairy-derived strains of Geobacillus and three dairy-derived strains of A. flavithermus were compared in two commercial milk formulations. Milk formulation B had relatively high sodium and low calcium and magnesium concentrations compared with those of milk formulation A, but the two formulations had comparable fat, protein, and lactose concentrations. Biofilm formation by the three Geobacillus isolates was up to 4 log CFU cm(-2) lower in milk formulation B than in milk formulation A after 6 to 18 h, and the difference was often significant (P ? 0.05). However, no significant differences (P ? 0.05) were found when biofilm formations by the three A. flavithermus isolates were compared in milk formulations A and B. Supplementation of milk formulation A with 100 mM NaCl significantly decreased (P ? 0.05) Geobacillus biofilm formation after 6 to 10 h. Furthermore, supplementation of milk formulation B with 2 mM CaCl2 or 2 mM MgCl2 significantly increased (P ? 0.05) Geobacillus biofilm formation after 10 to 18 h. It was concluded that relatively high free Na(+) and low free Ca(2+) and Mg(2+) concentrations in milk formulations are collectively required to inhibit biofilm formation by Geobacillus spp., whereas biofilm formation by A. flavithermus is not impacted by typical cation concentration differences of milk formulations. PMID:26002898

  20. Nuclear calcium signaling.

    PubMed

    Bengtson, C Peter; Bading, Hilmar

    2012-01-01

    Calcium is the major intracellular messenger linking synaptic activity in neurons to gene expression to control diverse functions including adaptive responses to synaptic activity as well as survival and death (Bading et al. 1993; Hardingham et al. 1997; Chawla and Bading 2001; West et al. 2001; Zhang et al. 2007; Flavell and Greenberg 2008; Mellstrom et al. 2008; Redmond 2008; Wayman et al. 2008; Bootman et al. 2009; Zhang et al. 2009; Hardingham and Bading 2010). Calcium entry at the synapse acts locally to activate signaling cascades which regulate posttranslational modifications essential for synaptic plasticity, such as the insertion of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) into the postsynaptic membrane (Soderling 2000; Malinow and Malenka 2002; Ehrlich and Malinow 2004). Synaptic activity can also evoke calcium signals in the nucleus which regulate gene pools largely through the phosphorylation of cAMP response element-binding protein (CREB) and its coactivator, CREB-binding protein (CBP) (Bading et al. 1993; Hardingham et al. 1997; Hardingham et al. 1999; Hu et al. 1999; Hardingham et al. 2001b; Impey et al. 2002; Zhang et al. 2009). Distinct mechanisms have been proposed to mediate synaptically generated calcium signals in subcompartments of pyramidal neurons; N-methyl-D -aspartate receptors (NMDARs) and ryanodine receptors have been implicated in the spine, inositol 3,4,5 triphosphate (IP3) receptors in the dendrites, and L-type voltage-gated calcium channels (VGCCs) at the soma and nucleus, although both NMDARs and IP3 receptors can also contribute to somatic and nuclear calcium signals under certain stimulation conditions (Nakamura et al. 1999; Bardo et al. 2006; Raymond and Redman 2006; Watanabe et al. 2006; Hong and Ross 2007; Hagenston et al. 2008; Bengtson et al. 2010). We review here the calcium signaling pathways underlying synaptically activated gene transcription leading to long-lasting changes in synaptic efficacy and memory as well as the physiological mechanisms by which synaptic activity evokes nuclear calcium signals. PMID:22351065

  1. Synthesis of sodium caseinate-calcium carbonate microspheres and their mineralization to bone-like apatite

    NASA Astrophysics Data System (ADS)

    Xu, Zhewu; Liang, Guobin; Jin, Lin; Wang, Zhenling; Xing, Chao; Jiange, Qing; Zhang, Zhiguang

    2014-06-01

    Phosphoproteins can induce and stabilize calcium carbonate (CaCO3) vaterite, which has desirable features for high reactivity. The purpose of this study was to synthesize bioactive CaCO3 microspheres for bone regeneration. Sodium caseinate (NaCas)-containing CaCO3 microspheres, with the crystal phase of vaterite, were synthesized by fast precipitation in an aqueous solution of CaCl2, Na2CO3, and 2 mg/mL of NaCas. The uniform microspheres exhibited rougher surfaces and lower negative charges than CaCO3 particles without NaCas addition. Fourier-transform infrared spectroscopy (FT-IR) of the microspheres showed characteristic peaks or bands corresponding to phosphate and hydroxyl groups. Thermogravimetric analysis (TGA) curves exhibited approximately 5% weight loss below 600 °C due to the decomposition of NaCas. Scanning electron microscope (SEM) images showed lath-like hydroxyapatite (HAp) on the surface after soaking in simulated body fluid (SBF) at 37 °C for 5 and 10 days. Energy dispersive X-ray spectrometry (EDS) revealed that the agglomerates were composed of Ca, C, O, P, Na, and Mg elements, and the Ca/P ratios ranged from 1.53 to 1.56. X-ray diffraction (XRD) patterns exhibited peaks characteristic of hydroxyapatite. The results of this study demonstrated that the addition of NaCas induced the formation of vaterite microspheres which possesses an enhanced apatite formation after soaking in SBF at 37 °C for 5 and 10 days. These NaCas-CaCO3 microspheres may be a potential biomaterial for bone regeneration.

  2. 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 ...

  3. An XAFS Study of Niobium chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Niobium chloride was studied with extended X-ray absorption fine structure spectroscopy (EXAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Although anhydrous Nb2Cl10 is more soluble in the basic melt than in the acidic melt, the EXAFS data shows that the coordination shell around the niobium does not change in the different ionic liquids. Both the acidic and basic melts show a coordination of five chlorides in the first shell. This indicates that in this series of ionic liquids, the Nb2Cl10 breaks up into two NbCl5 entities in both the acidic and the basic melts.

  4. Alginate–calcium films: Water vapor permeability and mechanical properties as affected by plasticizer and relative humidity

    Microsoft Academic Search

    Guadalupe I. Olivas; Gustavo V. Barbosa-Cánovas

    2008-01-01

    Alginate films containing dissimilar amounts of guluronate (G) and mannuronate (M): M\\/G?0.45 and M\\/G?1.5, soaked in a calcium chloride solution up to 20min were evaluated for water vapor permeability (WVP). M\\/G?0.45 films proved to be better moisture barriers at all calcium immersion times compared to M\\/G?1.5. WVP of M\\/G?0.45 and M\\/G?1.5 films decreased as time of immersion in calcium increased;

  5. Calcium nutrition and metabolism during infancy

    Microsoft Academic Search

    J. Kirk Bass; Gary M. Chan

    2006-01-01

    Calcium is a vital mineral for the developing newborn infant. This review discusses perinatal and neonatal calcium metabolism, with an emphasis on enteral calcium absorption and the nutritional factors affecting calcium bioavailability including the three major endocrine hormones involved in calcium metabolism: parathyroid hormone, vitamin D, and calcitonin. The placenta transports calcium to the fetus throughout pregnancy, with the largest

  6. Preparation of tadpole-shaped calcium alginate microparticles with sphericity control.

    PubMed

    Dang, T D; Joo, S W

    2013-02-01

    Monosized sodium alginate microdroplets are prepared using a flow-focusing microdevice by adjusting the flow rate of the continuous phase (soybean oil) and the dispersed phase (sodium alginate solution). The gelation process of the semi-product, sodium alginate microdroplets, occurs outside the channel in a calcium chloride solution to form tadpole-shaped calcium alginate microparticles. The microparticles prepared are in the range of 100-250 ?m in diameter, depending on the experimental conditions. The shape, size and size distribution of these calcium alginate microparticles depend strongly on the calcium solution concentration and the stirring mode. The shaping mechanism of the microparticles and the impact of the experimental conditions on particle shape and size are investigated. PMID:23107954

  7. Influence of the surfactant nature on the calcium carbonate synthesis in water-in-oil emulsion

    NASA Astrophysics Data System (ADS)

    Szcze?, Aleksandra

    2009-02-01

    Calcium carbonate has been precipitated from water-in-oil emulsions consisting of n-hexane/nonionic surfactant (Brij 30) and its mixture with cationic (DTAB) or anionic surfactant (SDS) to which calcium chloride and sodium carbonate were added. It was found that the surfactant kind and its amount can regulate the size, form and morphology of the precipitated particles. In case of nonionic surfactant the water/surfactant ratio is the most important parameter that allows to obtain small and regular calcium carbonate crystals. Addition of the DTAB results in different morphology of particles having the same crystal form, whereas addition of SDS changes the kind of emulsion from water-in-oil to oil-in-water. Moreover, light transmittance and backscattering light measurements have been used as a method to study the kinetics of calcium carbonate precipitation in emulsion systems.

  8. The initial phases of calcium and magnesium phosphates precipitated from solutions of high to medium concentrations

    NASA Astrophysics Data System (ADS)

    Abbona, F.; Madsen, H. E. Lundager; Boistelle, R.

    1986-04-01

    The precipitation of calcium and magnesium phosphates is performed at 25°C by mixing solutions of ammonium phosphate and solutions of calcium and magnesium chlorides under the condition [ P] = [ Ca] + [ Mg] in large pH intervals. Before any nucleation the phosphate concentration ranges from 0.50M to 0.01M. The phases first precipitated are CaHPO 4·2H 2O (brushite), CaHPO 4 (monetite), Ca 3(PO 4) 2· xH 2O (amorphous calcium phosphate), MgNH 4PO 4·6H 2O (struvite), and MgHPO 4·3H 2O (newberyite). The precipitation fields of each phase are determined and discussed as a function of pH, composition and supersaturation. The solutions are even supersaturated with respect to several other calcium phosphates but they never occur first even if their supersaturation is the highest.

  9. Visible light activated ion sensing using a photoacid polymer for calcium detection.

    PubMed

    Johns, Valentine K; Patel, Parth K; Hassett, Shelly; Calvo-Marzal, Percy; Qin, Yu; Chumbimuni-Torres, Karin Y

    2014-07-01

    Presented here is a sensing membrane consisting of a modified merocyanine photoacid polymer and a calcium ionophore in plasticized poly(vinyl chloride). This membrane is shown to actively exchange protons with calcium ions when switched ON after illumination at 470 nm, and the exchange can be followed by UV-vis spectroscopy. The sensing membrane shows no response in the ON state when calcium ions are absent. The limit of detection of the sensor is 5.0 × 10(-4) M with an upper detection limit of 1.0 M. Thus, we demonstrate for the first time the use of a visible light activated, lipophilic photoacid polymer in an ion-sensing membrane for calcium ions, which highly discriminates potassium, sodium, and magnesium ions. PMID:24893213

  10. Osteoinduction by calcium phosphate biomaterials

    Microsoft Academic Search

    Huipin Yuan; Zongjian Yang; Yubao Li; Xingdong Zhang; J. D. De Bruijn; K. De Groot

    1998-01-01

    Different materials were implanted in muscles of dogs to study the osteoinduction of calcium phosphate biomaterials. Bone formation was only seen in calcium phosphate biomaterials with micropores, and could be found in hydroxyapatite (HA) ceramic, tricalcium phosphate\\/hydroxyapatite ceramic (BCP), ß-TCP ceramic and calcium phosphate cement. The osteoinductive potential was different in different materials. The results indicate that osteoinduction can be

  11. Mechanisms of Renal Calcium Transport

    Microsoft Academic Search

    Peter A. Friedman

    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

  12. Plant protein and calcium balance

    Microsoft Academic Search

    Olufunmike A. Ajayi

    1977-01-01

    The effect of low protein intake from plant sources on calcium excretions and calcium balance of seven young adults was investigated. The diets (four combinations of egg, groundnut and soyabean nitrogen) furnished 43 g protein (0.58 g protein\\/kg) and 550 mg calcium daily.

  13. Metal chloride cathode for a battery

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (inventor); Distefano, Salvador (inventor); Bankston, C. Perry (inventor)

    1991-01-01

    A method of fabricating a rechargeable battery is disclosed which includes a positive electrode which contains a chloride of a selected metal when the electrode is in its active state. The improvement comprises fabricating the positive electrode by: providing a porous matrix composed of a metal; providing a solution of the chloride of the selected metal; and impregnating the matrix with the chloride from the solution.

  14. Indium-111 chloride imaging with ununited fractures

    SciTech Connect

    Sayle, B.A.; Fawcett, H.D.; Yudt, W.M.; Wang, S.C.; Mader, J.T.; Cierny, G. 3d.

    1987-03-01

    Twenty patients with ununited fractures and a suspicion of infection had In-111 chloride imaging. Surgically obtained cultures were positive for infection in 12 and negative in eight patients. In-111 chloride images were positive in all 12 patients with infection but also were positive in six of the patients with negative cultures. It is not possible to differentiate infected from noninfected ununited fractures by In-111 chloride imaging.

  15. Lysosomal calcium regulates autophagy.

    PubMed

    Medina, Diego L; Ballabio, Andrea

    2015-06-01

    Recent evidence has indicated that the lysosome is able to act as a signaling organelle that senses nutrient availability and generates an adaptive response that is important for cellular homeostasis. We recently discovered another example of lysosomal signaling where lysosomal calcium release activates the master autophagy regulator TFEB via the phosphatase calcineurin. PMID:26000950

  16. Calcium silicate insulation structure

    DOEpatents

    Kollie, Thomas G. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)

    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.

  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. Neurotransmitters Calcium ions

    E-print Network

    Cai, Long

    Actin Nerve terminal Active zone Neurotransmitters Calcium ions Sodium ions Ultrafast endocytosis.These`bouton-type'ter- minalscontainapproximately200synapticves- icles (30­40 nanometres across), each packed with about 2,000 neurotransmitter). It is thought that one to three of those docked vesicles are primed to release neurotransmitters by a process

  19. 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 ...

  20. Molecular Structure of Sodium chloride

    NSDL National Science Digital Library

    2002-08-15

    Sodium chloride, or simply (table) salt, is found in the mineral Halite (rock salt) but also in seawater, sweat, etc. It is used in industry and in our everyday life, for seasoning and perserving food or for winter road maintenance. Seawater contains a lot of salt, on average of 2.6% NaCl, or 26 million metric tons per cubic kilometer. In rock salt the NaCl content typically ranges between 95% and 99% NaCl, and mechanically evaporated salt and solar salt normally exceed 99% NaCl.

  1. Chloride Transporting CLC Proteins1

    NASA Astrophysics Data System (ADS)

    Pusch, Michael

    In the early 1980s, Chris Miller and colleagues described a curious "double-barreled" chloride channel from the electric organ of Torpedo fish reconstituted in planar lipid bilayers (Miller and White, 1980). Single-channel openings occurred in "bursts" separated by long closures. A single burst was characterized by the presence of two open conductance levels of equal size and the gating (i.e., openings and closings) during a burst could be almost perfectly described as a superposition of two identical and independent conductances that switched between open and closed states with voltage-dependent rates ? and ? (Hanke and Miller, 1983) (Fig. 8.1).

  2. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Vinyl chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall...joints are not permitted for pipe diameters exceeding 2 inches. Brazed joints are prohibited. (c) Each cargo tank shall be...

  3. X-ray absorption spectroscopy on the calcium cofactor to the manganese cluster in photosynthetic oxygen evolution

    Microsoft Academic Search

    Cinco; Roehl M

    1999-01-01

    Along with Mn, calcium and chloride ions are necessary cofactors for oxygen evolution in Photosystem II (PS II). To further test and verify whether Ca is close to the Mn cluster, the authors substituted strontium for Ca and probed from the Sr point of view for any nearby Mn. The extended X-ray absorption fine structure (EXAFS) of Sr-reactivated PS II

  4. 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...

  5. Chloride ingress in cement paste and mortar

    SciTech Connect

    Jensen, O.M.; Hansen, P.F.; Coats, A.M.; Glasser, F.P.

    1999-09-01

    In this paper chloride ingress in cement paste and mortar is followed by electron probe microanalysis. The influence of several paste and exposure parameters on chloride ingress are examined (e.g., water-cement ratio, silica fume addition, exposure time, and temperature). The measurements are modelled on Fick's law modified by a term for chloride binding. Inclusion of chloride binding significantly improves the profile shape of the modelled ingress profiles. The presence of fine aggregate and formation of interfacial transition zones at paste-aggregate boundaries does not significantly affect diffusion rates.

  6. Potentiometric titration of chloride in plant tissue extracts using the chloride ion electrode

    Microsoft Academic Search

    R. L. LaCroix; D. R. Keeney; L. M. Walsh

    1970-01-01

    Use of the chloride specific ion electrode to determine chloride in plants was evaluted. Direct potentiometric determination of chloride by the electrode resulted in unreproducible and extremely high chloride values. However, use of this electrode to indicate the end point in titration of the tissue?extract mixture with AgNO3 gave results nearly identical to those obtained by the Mohr procedure. The

  7. The hydration products of Portland cement in the presence of tin(II) chloride

    SciTech Connect

    Hill, J.; Sharp, J.H

    2003-01-01

    The hydration products of Portland cement pastes cured using water containing tin(II) chloride have been compared with those using distilled water. In the latter case, the expected products - portlandite, ettringite and calcite - were observed. The X-ray diffraction patterns of the cement pastes cured in the presence of tin(II) chloride showed several additional peaks that have been attributed to the formation of calcium hydroxo-stannate, CaSn(OH){sub 6}, and Friedel's salt (tetracalcium aluminate dichloride-10-hydrate), Ca{sub 3}Al{sub 2}O{sub 6}{center_dot}CaCl{sub 2}{center_dot}10H{sub 2}O. The amount of portlandite formed was reduced in the presence of tin(II) chloride. Calcium hydroxo-stannate contains tin in the +IV oxidation state and equations are presented to account for the oxidation of Sn(II) to Sn(IV) preceding the formation of CaSn(OH){sub 6} and Friedel's salt.

  8. Mercury Control with Calcium-Based Sorbents and Oxidizing Agents

    SciTech Connect

    Thomas K. Gale

    2005-07-01

    This Final Report contains the test descriptions, results, analysis, correlations, theoretical descriptions, and model derivations produced from many different investigations performed on a project funded by the U.S. Department of Energy, to investigate calcium-based sorbents and injection of oxidizing agents for the removal of mercury. Among the technologies were (a) calcium-based sorbents in general, (b) oxidant-additive sorbents developed originally at the EPA, and (c) optimized calcium/carbon synergism for mercury-removal enhancement. In addition, (d) sodium-tetrasulfide injection was found to effectively capture both forms of mercury across baghouses and ESPs, and has since been demonstrated at a slipstream treating PRB coal. It has been shown that sodium-tetrasulfide had little impact on the foam index of PRB flyash, which may indicate that sodium-tetrasulfide injection could be used at power plants without affecting flyash sales. Another technology, (e) coal blending, was shown to be an effective means of increasing mercury removal, by optimizing the concentration of calcium and carbon in the flyash. In addition to the investigation and validation of multiple mercury-control technologies (a through e above), important fundamental mechanism governing mercury kinetics in flue gas were elucidated. For example, it was shown, for the range of chlorine and unburned-carbon (UBC) concentrations in coal-fired utilities, that chlorine has much less effect on mercury oxidation and removal than UBC in the flyash. Unburned carbon enhances mercury oxidation in the flue gas by reacting with HCl to form chlorinated-carbon sites, which then react with elemental mercury to form mercuric chloride, which subsequently desorbs back into the flue gas. Calcium was found to enhance mercury removal by stabilizing the oxidized mercury formed on carbon surfaces. Finally, a model was developed to describe these mercury adsorption, desorption, oxidation, and removal mechanisms, including the synergistic enhancement of mercury removal by calcium.

  9. Calcium carbonate polymorph control using droplet-based microfluidics.

    PubMed

    Yashina, Alexandra; Meldrum, Fiona; Demello, Andrew

    2012-06-01

    Calcium carbonate (CaCO(3)) is one of the most abundant minerals and of high importance in many areas of science including global CO(2) exchange, industrial water treatment energy storage, and the formation of shells and skeletons. Industrially, calcium carbonate is also used in the production of cement, glasses, paints, plastics, rubbers, ceramics, and steel, as well as being a key material in oil refining and iron ore purification. CaCO(3) displays a complex polymorphic behaviour which, despite numerous experiments, remains poorly characterised. In this paper, we report the use of a segmented-flow microfluidic reactor for the controlled precipitation of calcium carbonate and compare the resulting crystal properties with those obtained using both continuous flow microfluidic reactors and conventional bulk methods. Through combination of equal volumes of equimolar aqueous solutions of calcium chloride and sodium carbonate on the picoliter scale, it was possible to achieve excellent definition of both crystal size and size distribution. Furthermore, highly reproducible control over crystal polymorph could be realised, such that pure calcite, pure vaterite, or a mixture of calcite and vaterite could be precipitated depending on the reaction conditions and droplet-volumes employed. In contrast, the crystals precipitated in the continuous flow and bulk systems comprised of a mixture of calcite and vaterite and exhibited a broad distribution of sizes for all reaction conditions investigated. PMID:22655005

  10. Calcium carbonate polymorph control using droplet-based microfluidics

    PubMed Central

    Yashina, Alexandra; Meldrum, Fiona; deMello, Andrew

    2012-01-01

    Calcium carbonate (CaCO3) is one of the most abundant minerals and of high importance in many areas of science including global CO2 exchange, industrial water treatment energy storage, and the formation of shells and skeletons. Industrially, calcium carbonate is also used in the production of cement, glasses, paints, plastics, rubbers, ceramics, and steel, as well as being a key material in oil refining and iron ore purification. CaCO3 displays a complex polymorphic behaviour which, despite numerous experiments, remains poorly characterised. In this paper, we report the use of a segmented-flow microfluidic reactor for the controlled precipitation of calcium carbonate and compare the resulting crystal properties with those obtained using both continuous flow microfluidic reactors and conventional bulk methods. Through combination of equal volumes of equimolar aqueous solutions of calcium chloride and sodium carbonate on the picoliter scale, it was possible to achieve excellent definition of both crystal size and size distribution. Furthermore, highly reproducible control over crystal polymorph could be realised, such that pure calcite, pure vaterite, or a mixture of calcite and vaterite could be precipitated depending on the reaction conditions and droplet-volumes employed. In contrast, the crystals precipitated in the continuous flow and bulk systems comprised of a mixture of calcite and vaterite and exhibited a broad distribution of sizes for all reaction conditions investigated. PMID:22655005

  11. Chloride Analysis of RFSA Second Campaign Dissolver Solution

    SciTech Connect

    Holcomb, H.P.

    2001-05-17

    The dissolver solution from the second RFSA campaign was analyzed for chloride using the recently-developed turbidimetric method. Prior to chloride removal in head end, the solution contained 1625 ppm chloride. After chloride removal with Hg(I) and prior to feeding to solvent extraction, the solution contained only 75 ppm chloride. This report discusses those analysis results.

  12. Numerical Modeling of Electrochemical Chloride Removal from Concrete

    Microsoft Academic Search

    Q Sa’id-Shawqi; C Arya; P. R Vassie

    1998-01-01

    A numerical model of electrochemical chloride removal from concrete (desalination) based on the Nernst-Planck and the Laplace equations is proposed. The model relies on experimentally derived chloride transport number profiles. It is shown that the model can make realistic predictions of both the chloride removed and the chloride remaining in concrete made with admixed sodium chloride.

  13. Enrofloxacin hydro­chloride dihydrate

    PubMed Central

    Miranda-Calderón, Jorge E.; Gutiérrez, Lilia; Flores-Alamo, Marcos; García-Gutiérrez, Ponciano; Sumano, Héctor

    2014-01-01

    The asymmetric unit of the title compound, C19H23FN3O3 +·Cl?·2H2O [systematic name: 4-(3-carb­oxy-1-cyclo­propyl-6-fluoro-4-oxo-1,4-di­hydro­quin­o­lin-7-yl)-1-ethyl­piperazin-1-ium chloride dihydrate], consists of two independent monocations of the protonated enrofloxacin, two chloride anions and four water mol­ecules. In the cations, the piperazinium rings adopt chair conformations and the dihedral angles between the cyclo­propyl ring and the 10-membered quinoline ring system are 56.55?(2) and 51.11?(2)°. An intra­molecular O—H?O hydrogen bond is observed in each cation. In the crystal, the components are connected via O—H?Cl, N—H?Cl and O—H?O hydrogen bonds, and a ?–? inter­action between the benzene rings [centroid–centroid distance = 3.6726?(13)?Å], resulting in a three-dimensional array. PMID:24826167

  14. Chloride Deficiency in Holstein Calves from a Low Chloride Diet and Removal of Abomasal Contents1

    Microsoft Academic Search

    M. W. Neathery; D. M. Blackmon; W. J. Miller; Shelia Heinmiller; Susan McGuire; J. M. Tarabula; R. P. Gentry; J. C. Allen

    1981-01-01

    Chloride deficiency signs were pro- duced in young Holstein calves by a low chloride diet (.063% chlorine) and daily removal of chloride in abomasal contents. General clinical signs included anorexia, weight loss, lethargy, mild polydipsia, and mild polyuria. In latter stages of the deficiency, severe eye defects (scleral injection, sunken eyes, scaliness around eyes) and reduced respiration rate became evident.

  15. Structure of wood extract colloids and effect of CaCl2 on the molecular mobility

    E-print Network

    Turro, Nicholas J.

    , University of Tasmania, Private Bag 75, Hobart, 7001,Tasmania, Australia 2) Australian Pulp and Paper Chemistry, Norske Skog Paper Mills (Australia) Ltd, Boyer 7540, Tasmania, Australia 4) Department of Earth

  16. Effects of Inclusions in HSLA Carbon Steel on Pitting Corrosion in CaCl2

    SciTech Connect

    M. Ziomek-Moroz; S. Bullard; K. Rozman; J.J. Kruzic

    2011-12-05

    Susceptibility of high strength low alloy steel to localized corrosion was studied in 6.7 M CaCl{sub 2} for oil and natural gas drilling applications. Results of the immersion and electrochemical experiments showed that the steel is susceptible to pitting corrosion. Optical microscopy investigations of the polished samples revealed that 10% of the surface area was occupied by defects in the form of pits. The energy dispersive X-ray (EDX) and wavelength dispersive X-ray (WDX) chemical analyses revealed higher concentrations of Mn and S compared to the metal matrix in defected areas. These areas served as the sites for development of corrosion pits during both immersion and electrochemical experiments. The fatigue results of the corroded samples indicate that if the pit was the most significant defect, the fatigue crack initiated and propagated at this site.

  17. Metabolomic assessment reveals an elevated level of glucosinolate content in CaCl? treated broccoli microgreens.

    PubMed

    Sun, Jianghao; Kou, Liping; Geng, Ping; Huang, Huilian; Yang, Tianbao; Luo, Yaguang; Chen, Pei

    2015-02-18

    Preharvest calcium application has been shown to increase broccoli microgreen yield and extend shelf life. In this study, we investigated the effect of calcium application on its metabolome using ultra-high-performance liquid chromatography with mass spectrometry. The data collected were analyzed using principal component analysis and orthogonal projection to latent structural discriminate analysis. Chemical composition comparison shows that glucosinolates, a very important group of phytochemicals, are the major compounds enhanced by preharvest treatment with 10 mM calcium chloride (CaCl2). Aliphatic glucosinolates (glucoerucin, glucoiberin, glucoiberverin, glucoraphanin, pentyl glucosinolate, and hexyl glucosinolate) and indolic glucosinolates (glucobrassicin, neoglucobrassicin, and 4-hydroxyglucobrassicin) were increased significantly in the CaCl2 treated microgreens using metabolomic approaches. Targeted glucosinolate analysis using the ISO 9167-1 method was further employed to confirm the findings. Results indicate that glucosinolates can be considered as a class of compounds that are responsible for the difference between two groups and a higher glucosinolate level was found in CaCl2 treated groups at each time point after harvest in comparison with the control group. PMID:25594226

  18. Lithium prevents early cytosolic calcium increase and secondary injurious calcium overload in glycolytically inhibited endothelial cells

    SciTech Connect

    Bosche, Bert, E-mail: bert.bosche@uk-essen.de [Department of Neurology, University of Duisburg-Essen (Germany) [Department of Neurology, University of Duisburg-Essen (Germany); Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany); Schäfer, Matthias, E-mail: matthias.schaefer@sanofi.com [Institute of Physiology, Justus-Liebig-University Giessen (Germany)] [Institute of Physiology, Justus-Liebig-University Giessen (Germany); Graf, Rudolf, E-mail: rudolf.graf@nf.mpg.de [Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany)] [Max Planck Institute for Neurological Research with Klaus-Joachim-Zülch Laboratories of the Max Planck Society and the Medical Faculty of the University of Cologne (Germany); Härtel, Frauke V., E-mail: frauke.haertel@tu-dresden.de [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany); Schäfer, Ute, E-mail: ute.schaefer@medunigraz.at [Research Unit for Experimental Neurotraumatology, Medical University of Graz (Austria)] [Research Unit for Experimental Neurotraumatology, Medical University of Graz (Austria); Noll, Thomas, E-mail: thomas.noll@tu-dresden.de [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany)] [Institute of Physiology, Medical Faculty Carl Gustav Carus, Technical University Dresden (Germany)

    2013-05-03

    Highlights: •We investigate free calcium as a central signalling element in endothelial cells. •Inhibition of glycolysis with 2-deoxy-D-glucose reduces cellular ATP. •This manoeuvre leads to a biphasic increase and overload of free calcium. •Pre-treatment with lithium for 24 h abolishes both phases of the calcium increase. •This provides a new strategy to protect endothelial calcium homeostasis and barrier function. -- Abstract: Cytosolic free calcium concentration ([Ca{sup 2+}]{sub i}) is a central signalling element for the maintenance of endothelial barrier function. Under physiological conditions, it is controlled within narrow limits. Metabolic inhibition during ischemia/reperfusion, however, induces [Ca{sup 2+}]{sub i} overload, which results in barrier failure. In a model of cultured porcine aortic endothelial monolayers (EC), we addressed the question of whether [Ca{sup 2+}]{sub i} overload can be prevented by lithium treatment. [Ca{sup 2+}]{sub i} and ATP were analysed using Fura-2 and HPLC, respectively. The combined inhibition of glycolytic and mitochondrial ATP synthesis by 2-desoxy-D-glucose (5 mM; 2-DG) plus sodium cyanide (5 mM; NaCN) caused a significant decrease in cellular ATP content (14 ± 1 nmol/mg protein vs. 18 ± 1 nmol/mg protein in the control, n = 6 culture dishes, P < 0.05), an increase in [Ca{sup 2+}]{sub i} (278 ± 24 nM vs. 71 ± 2 nM in the control, n = 60 cells, P < 0.05), and the formation of gaps between adjacent EC. These observations indicate that there is impaired barrier function at an early state of metabolic inhibition. Glycolytic inhibition alone by 10 mM 2-DG led to a similar decrease in ATP content (14 ± 2 nmol/mg vs. 18 ± 1 nmol/mg in the control, P < 0.05) with a delay of 5 min. The [Ca{sup 2+}]{sub i} response of EC was biphasic with a peak after 1 min (183 ± 6 nM vs. 71 ± 1 nM, n = 60 cells, P < 0.05) followed by a sustained increase in [Ca{sup 2+}]{sub i}. A 24-h pre-treatment with 10 mM of lithium chloride before the inhibition of ATP synthesis abolished both phases of the 2-DG-induced [Ca{sup 2+}]{sub i} increase. This effect was not observed when lithium chloride was added simultaneously with 2-DG. We conclude that lithium chloride abolishes the injurious [Ca{sup 2+}]{sub i} overload in EC and that this most likely occurs by preventing inositol 3-phosphate-sensitive Ca{sup 2+}-release from the endoplasmic reticulum. Though further research is needed, these findings provide a novel option for therapeutic strategies to protect the endothelium against imminent barrier failure.

  19. Stochastic calcium mechanisms cause dendritic calcium spike variability.

    PubMed

    Anwar, Haroon; Hepburn, Iain; Nedelescu, Hermina; Chen, Weiliang; De Schutter, Erik

    2013-10-01

    Bursts of dendritic calcium spikes play an important role in excitability and synaptic plasticity in many types of neurons. In single Purkinje cells, spontaneous and synaptically evoked dendritic calcium bursts come in a variety of shapes with a variable number of spikes. The mechanisms causing this variability have never been investigated thoroughly. In this study, a detailed computational model using novel simulation routines is applied to identify the roles that stochastic ion channels, spatial arrangements of ion channels, and stochastic intracellular calcium have toward producing calcium burst variability. Consistent with experimental recordings from rats, strong variability in the burst shape is observed in simulations. This variability persists in large model sizes in contrast to models containing only voltage-gated channels, where variability reduces quickly with increase of system size. Phase plane analysis of Hodgkin-Huxley spikes and of calcium bursts identifies fluctuation in phase space around probabilistic phase boundaries as the mechanism determining the dependence of variability on model size. Stochastic calcium dynamics are the main cause of calcium burst fluctuations, specifically the calcium activation of mslo/BK-type and SK2 channels. Local variability of calcium concentration has a significant effect at larger model sizes. Simulations of both spontaneous and synaptically evoked calcium bursts in a reconstructed dendrite show, in addition, strong spatial and temporal variability of voltage and calcium, depending on morphological properties of the dendrite. Our findings suggest that stochastic intracellular calcium mechanisms play a crucial role in dendritic calcium spike generation and are therefore an essential consideration in studies of neuronal excitability and plasticity. PMID:24089492

  20. Chloride Accumulators NKCC1 and AE2 in Mouse GnRH Neurons: Implications for GABAA Mediated Excitation

    PubMed Central

    Taylor-Burds, Carol; Cheng, Paul; Wray, Susan

    2015-01-01

    A developmental “switch” in chloride transporters occurs in most neurons resulting in GABAA mediated hyperpolarization in the adult. However, several neuronal cell subtypes maintain primarily depolarizing responses to GABAA receptor activation. Among this group are gonadotropin-releasing hormone-1 (GnRH) neurons, which control puberty and reproduction. NKCC1 is the primary chloride accumulator in neurons, expressed at high levels early in development and contributes to depolarization after GABAA receptor activation. In contrast, KCC2 is the primary chloride extruder in neurons, expressed at high levels in the adult and contributes to hyperpolarization after GABAA receptor activation. Anion exchangers (AEs) are also potential modulators of responses to GABAA activation since they accumulate chloride and extrude bicarbonate. To evaluate the mechanism(s) underlying GABAA mediated depolarization, GnRH neurons were analyzed for 1) expression of chloride transporters and AEs in embryonic, pre-pubertal, and adult mice 2) responses to GABAA receptor activation in NKCC1-/- mice and 3) function of AEs in these responses. At all ages, GnRH neurons were immunopositive for NKCC1 and AE2 but not KCC2 or AE3. Using explants, calcium imaging and gramicidin perforated patch clamp techniques we found that GnRH neurons from NKCC1-/- mice retained relatively normal responses to the GABAA agonist muscimol. However, acute pharmacological inhibition of NKCC1 with bumetanide eliminated the depolarization/calcium response to muscimol in 40% of GnRH neurons from WT mice. In the remaining GnRH neurons, HCO3- mediated mechanisms accounted for the remaining calcium responses to muscimol. Collectively these data reveal mechanisms responsible for maintaining depolarizing GABAA mediated transmission in GnRH neurons. PMID:26110920

  1. Chloride Accumulators NKCC1 and AE2 in Mouse GnRH Neurons: Implications for GABAA Mediated Excitation.

    PubMed

    Taylor-Burds, Carol; Cheng, Paul; Wray, Susan

    2015-01-01

    A developmental "switch" in chloride transporters occurs in most neurons resulting in GABAA mediated hyperpolarization in the adult. However, several neuronal cell subtypes maintain primarily depolarizing responses to GABAA receptor activation. Among this group are gonadotropin-releasing hormone-1 (GnRH) neurons, which control puberty and reproduction. NKCC1 is the primary chloride accumulator in neurons, expressed at high levels early in development and contributes to depolarization after GABAA receptor activation. In contrast, KCC2 is the primary chloride extruder in neurons, expressed at high levels in the adult and contributes to hyperpolarization after GABAA receptor activation. Anion exchangers (AEs) are also potential modulators of responses to GABAA activation since they accumulate chloride and extrude bicarbonate. To evaluate the mechanism(s) underlying GABAA mediated depolarization, GnRH neurons were analyzed for 1) expression of chloride transporters and AEs in embryonic, pre-pubertal, and adult mice 2) responses to GABAA receptor activation in NKCC1-/- mice and 3) function of AEs in these responses. At all ages, GnRH neurons were immunopositive for NKCC1 and AE2 but not KCC2 or AE3. Using explants, calcium imaging and gramicidin perforated patch clamp techniques we found that GnRH neurons from NKCC1-/- mice retained relatively normal responses to the GABAA agonist muscimol. However, acute pharmacological inhibition of NKCC1 with bumetanide eliminated the depolarization/calcium response to muscimol in 40% of GnRH neurons from WT mice. In the remaining GnRH neurons, HCO3- mediated mechanisms accounted for the remaining calcium responses to muscimol. Collectively these data reveal mechanisms responsible for maintaining depolarizing GABAA mediated transmission in GnRH neurons. PMID:26110920

  2. Hydrocracking with molten zinc chloride catalyst containing 2-12% ferrous chloride

    DOEpatents

    Zielke, Clyde W. (McMurray, PA); Bagshaw, Gary H. (Library, PA)

    1981-01-01

    In a process for hydrocracking heavy aromatic polynuclear carbonaceous feedstocks to produce hydrocarbon fuels boiling below about 475.degree. C. by contacting the feedstocks with hydrogen in the presence of a molten zinc chloride catalyst and thereafter separating at least a major portion of the hydrocarbon fuels from the spent molten zinc chloride catalyst, an improvement comprising: adjusting the FeCl.sub.2 content of the molten zinc chloride to from about 2 to about 12 mol percent based on the mixture of ferrous chloride and molten zinc chloride.

  3. Carbonation and electrochemical chloride extraction from concrete

    Microsoft Academic Search

    N. M. Ihekwaba; B. B. Hope; C. M. Hansson

    1996-01-01

    Chloride ingress into steel reinforced concrete (r.c.), and the subsequent application of electrochemical chloride extraction (ECE) are shown to be considerably retarded by the presence of a carbonation front. Four concrete blocks each reinforced with two layers of steel mats in two different configurations were electrochemically treated. One block of each type was initially carbonated to a depth of about

  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. 49 CFR 179.102-17 - Hydrogen chloride, refrigerated liquid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Hydrogen chloride, refrigerated liquid...114 and 120) § 179.102-17 Hydrogen chloride, refrigerated liquid. Each tank car used to transport hydrogen chloride, refrigerated liquid...

  7. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Quaternary ammonium chloride combination...Preservatives § 172.165 Quaternary ammonium chloride combination... The food additive, quaternary ammonium chloride combination...7.0-8.0; total amines, maximum 1 percent...

  8. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Quaternary ammonium chloride combination...Preservatives § 172.165 Quaternary ammonium chloride combination... The food additive, quaternary ammonium chloride combination...7.0-8.0; total amines, maximum 1 percent...

  9. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Quaternary ammonium chloride combination...Preservatives § 172.165 Quaternary ammonium chloride combination... The food additive, quaternary ammonium chloride combination...7.0-8.0; total amines, maximum 1 percent...

  10. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2009-04-01 true Quaternary ammonium chloride combination...Preservatives § 172.165 Quaternary ammonium chloride combination... The food additive, quaternary ammonium chloride combination...7.0-8.0; total amines, maximum 1 percent...

  11. 21 CFR 172.165 - Quaternary ammonium chloride combination.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Quaternary ammonium chloride combination...Preservatives § 172.165 Quaternary ammonium chloride combination... The food additive, quaternary ammonium chloride combination...7.0-8.0; total amines, maximum 1 percent...

  12. Factors influencing electrochemical removal of chloride from concrete

    SciTech Connect

    Arya, C.; Sa`id-Shawqi, Q. [South Bank Univ., London (United Kingdom). Div. of Civil Engineering] [South Bank Univ., London (United Kingdom). Div. of Civil Engineering; Vassie, P.R.W. [Transport Research Lab., Crowthorne (United Kingdom)] [Transport Research Lab., Crowthorne (United Kingdom)

    1996-06-01

    Electrochemical chloride removal was studied using prisms made from concrete containing various levels of chlorides derived from sodium chloride added during mixing. The amount of chloride removed during the treatment was assessed by analyzing the anolyte. Chloride removal increased with increasing applied potential, number of reinforcing bars at a particular depth and initial chloride content of the concrete. A greater percentage of chloride was removed from prisms where the thickness of the chloride bearing layer of concrete was less than the depth of cover to the reinforcement. Where the thickness of the chloride bearing layer exceeded the cover to the reinforcement, the use of an external cathode significantly increased the total amount of chloride removed. Chloride removal from a face remote from the source of the chloride contamination (soffit desalination) was shown to be feasible.

  13. Diffusion behavior of chloride ions in concrete

    SciTech Connect

    Zhang, T.; Gjoerv, O.E. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Div. of Building Materials] [Norwegian Univ. of Science and Technology, Trondheim (Norway). Div. of Building Materials

    1996-06-01

    In the present paper, an analysis of the diffusion behavior of chloride ions in concrete is presented. In concentrated electrolytic aqueous solutions such as seawater or that typically used in laboratory experiments, the effect of ionic interaction may significantly reduce the chemical potential and thus the driving force of the diffusing species. Because of different drift velocities of the cations and chloride ions in the solution, the lagging motion of the cations will also retard the drift velocity of the chlorides. In addition, both the electrical double layer forming on the solid surface and the chemical binding may significantly interfere with the transport of the chloride ions. As a result, the diffusion behavior of the chloride ions in concrete is a more complex and complicated transport process than what can be described by Fick`s law of diffusion.

  14. Calcium signaling in lymphocytes

    PubMed Central

    Oh-hora, Masatsugu; Rao, Anjana

    2008-01-01

    In cells of the immune system, calcium signals are essential for diverse cellular functions including differentiation, effector function and gene transcription. After engagement of immunoreceptors such as T-cell and B-cell antigen receptors and the Fc receptors on mast cells and NK cells, the intracellular concentration of calcium ions is increased through the sequential operation of two interdependent processes: depletion of endoplasmic reticulum Ca2+ stores as a result of binding of inositol trisphosphate (IP3) to IP3 receptors, followed by “store-operated” Ca2+ entry through plasma membrane Ca2+ channels. In lymphocytes, mast cells and other immune cell types, store-operated Ca2+ entry through specialised Ca2+ release-activated calcium (CRAC) channels constitutes the major pathway of intracellular Ca2+ increase. A recent breakthrough in our understanding of CRAC channel function is the identification of STIM and ORAI, two essential regulators of CRAC channel function. This review focuses on the signaling pathways upstream and downstream of Ca2+ influx (the STIM/ ORAI and calcineurin/ NFAT pathways respectively). PMID:18515054

  15. Corrosion inhibitors in concrete. Part II: Effect on chloride threshold values for corrosion of steel in synthetic pore solutions

    SciTech Connect

    Mammoliti, L.; Hansson, C.M.; Hope, B.B.

    1999-10-01

    The effectiveness of four commercially available corrosion inhibitors for use in cement-based materials was assessed in synthetic concrete pore solution containing chlorides. The effect of the surface topography of the sample and the composition of the pore solution was also assessed. Although in a parallel study the inhibitors were observed to delay the onset of corrosion, in these tests in pore solution they were found to be ineffective in increasing the chloride threshold value of reinforcing steel exposed to chlorides and had little influence on the progression of corrosion once initiated. This suggests that chemical reactions within the cement phase are responsible for the observed results. Metallographically polished samples proved the most resistant to corrosion regardless of electrolyte composition and samples with all surface finishes exhibited lower resistance in solutions containing only calcium hydroxide than in the higher pH synthetic concrete pore solutions.

  16. Sodium-metal chloride batteries

    NASA Technical Reports Server (NTRS)

    Ratnakumar, B. V.; Attia, A. I.; Halpert, G.

    1992-01-01

    It was concluded that rapid development in the technology of sodium metal chloride batteries has been achieved in the last decade mainly due to the: expertise available with sodium sulfur system; safety; and flexibility in design and fabrication. Long cycle lives of over 1000 and high energy densities of approx. 100 Wh/kg have been demonstrated in both Na/FeCl2 and Na/NiCl2 cells. Optimization of porous cathode and solid electrolyte geometries are essential for further enhancing the battery performance. Fundamental studies confirm the capabilities of these systems. Nickel dichloride emerges as the candidate cathode material for high power density applications such as electric vehicle and space.

  17. Chloride penetration into concrete structures in the marine atmosphere zone – Relationship between deposition of chlorides on the wet candle and chlorides accumulated into concrete

    Microsoft Academic Search

    G. R. Meira; C. Andrade; I. J. Padaratz; C. Alonso; J BORBAJR

    2007-01-01

    The relationship between chlorides from marine aerosol and chlorides accumulated into concrete is discussed in this paper. The experimental programme comprised an environmental characterisation, with climatic and chloride deposition data, and a study of chloride penetration into concrete based on natural exposure of specimens in a marine atmosphere zone. Results show that salt concentration in marine aerosol strongly decreases in

  18. APPLICATION OF VACUUM SALT DISTILLATION TECHNOLOGY FOR THE REMOVAL OF FLUORIDE AND CHLORIDE FROM LEGACY FISSILE MATERIALS

    SciTech Connect

    Pierce, R.; Peters, T.

    2011-11-01

    Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and the Savannah River Site (SRS) HB-Line Facility designed, developed, tested, and successfully deployed a production-scale system for the distillation of sodium chloride (NaCl) and potassium chloride (KCl) from plutonium oxide (PuO{sub 2}). Subsequent efforts adapted the vacuum salt distillation (VSD) technology for the removal of chloride and fluoride from less-volatile halide salts at the same process temperature and vacuum. Calcium chloride (CaCl{sub 2}), calcium fluoride (CaF{sub 2}), and plutonium fluoride (PuF{sub 3}) were of particular concern. To enable the use of the same operating conditions for the distillation process, SRNL employed in situ exchange reactions to convert the less-volatile halide salts to compounds that facilitated the distillation of halide without removal of plutonium. SRNL demonstrated the removal of halide from CaCl{sub 2}, CaF{sub 2} and PuF{sub 3} below 1000 C using VSD technology.

  19. Evaluation of various parameters of calcium-alginate immobilization method for enhanced alkaline protease production by Bacillus licheniformis NCIM-2042 using statistical methods

    Microsoft Academic Search

    Ravichandra Potumarthi; Ch. Subhakar; A. Pavani; Annapurna Jetty

    2008-01-01

    Calcium-alginate immobilization method for the production of alkaline protease by Bacillus licheniformis NCIM-2042 was optimized statistically. Four variables, such as sodium-alginate concentration, calcium chloride concentration, inoculum size and agitation speed were optimized by 24 full factorial central composite design and subsequent analysis and model validation by a second-order regression equation. Eleven carbon, 11 organic nitrogen and seven inorganic nitrogen sources

  20. Wax-incorporated Emulsion Gel Beads of Calcium Pectinate for Intragastric Floating Drug Delivery

    Microsoft Academic Search

    Pornsak Sriamornsak; Panida Asavapichayont; Jurairat Nunthanid; Manee Luangtana-anan; Sontaya Limmatvapirat; Suchada Piriyaprasarth

    2008-01-01

    The purpose of this study was to prepare wax-incorporated pectin-based emulsion gel beads using a modified emulsion-gelation\\u000a method. The waxes in pectin–olive oil mixtures containing a model drug, metronidazole, were hot-melted, homogenized and then\\u000a extruded into calcium chloride solution. The beads formed were separated, washed with distilled water and dried for 12 h.\\u000a The influence of various types and amounts of

  1. 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.

  2. Calcium Phosphate Biomaterials: An Overview

    Microsoft Academic Search

    Huipin Yuan; KLAAS DE GROOT

    Calcium phosphates are used by our body to build bones and are being applied to produce biomaterials for bone repair. It is\\u000a well-known that calcium phosphate biomaterials guide new bone formation, form a tight bond with the newly formed bone, and\\u000a are therefore, by definition, osteoconductive. Besides their osteoconductive property, it was found that calcium phosphate\\u000a biomaterials, only with specific

  3. Calcium signaling in immune cells

    Microsoft Academic Search

    Jean-Pierre Kinet; Monika Vig

    2008-01-01

    Calcium acts as a second messenger in many cell types, including lymphocytes. Resting lymphocytes maintain a low concentration of Ca2+. However, engagement of antigen receptors induces calcium influx from the extracellular space by several routes. A chief mechanism of Ca2+ entry in lymphocytes is through store-operated calcium (SOC) channels. The identification of two important molecular components of SOC channels, CRACM1

  4. Materials for Conoco zinc chloride hydrocracking process

    SciTech Connect

    Baylor, V.B.; Keiser, J.R.; DeVan, J.H.

    1980-01-01

    Use of zinc chloride to augment hydrogenation of coal and yield a high-octane gasoline product is the most significant feature of a coal liquefaction process being developed by Conoco Coal Development Company. The zinc chloride catalyst is regenerated in a fluidized sand bed, where the spent melt is mixed with air and hydrogen chloride at about 1000/sup 0/C. Recovery is completed at 370/sup 0/C in a condenser, where the zinc chloride is collected and the oxygen and sulfur are separated as H/sub 2/O and SO/sub 2/. The economic viability of the entire process is highly dependent on almost complete recovery of the zinc chloride. The severe environmental conditions of this recovery process cause unique materials problems. Although high-temperature oxidation and sulfidation are being studied in related programs, suitable materials to resist their combined effects along with those of chlorides have not yet been specifically addressed. Common engineering materials, such as the austenitic stainless steels and many nickel-base alloys, are unsuitable because of their inability to tolerate the elevated temperatures and sulfidation, respectively. The objectives of this task are to screen various metallic and ceramic materials for resistance to the zinc chloride recovery system environment and to determine the nature of the attack by exposing coupons to the simulated environment in the laboratory.

  5. Amorphous silica solubilities—II. Effect of aqueous salt solutions at 25°C

    NASA Astrophysics Data System (ADS)

    Marshall, William L.; Warakomski, John M.

    1980-07-01

    The solubility of amorphous silica was measured at 25°C in ten separate sets of aqueous salt solutions—potassium chloride, potassium nitrate, sodium chloride, lithium chloride, lithium nitrate, magnesium chloride, calcium chloride, magnesium sulfate, sodium bicarbonate and sodium sulfate. The concentrations of the salts were varied from zero to saturation with both salt and amorphous silica. With increasing concentration of salt, the solubility of amorphous silica always decreased as expected from an average value of 0.00218 m in water. Nevertheless, the extent of decrease differed greatly from a 6% decrease in a solution saturated with NaHCO 3 to a 95.7% decrease in a solution saturated with CaCl 2. A striking correlation was observed: In the 1-1 and 2-1 electrolyte salt solutions at a given molality the effect on the solubility of silica depended upon the cation in the order Mg 2+, Ca 2+ > Li + > Na + > K +.

  6. The bioavailability of dietary calcium.

    PubMed

    Guéguen, L; Pointillart, A

    2000-04-01

    This update focuses on the bioavailability of dietary calcium for humans. Fundamentals of calcium metabolism, intestinal absorption, urinary excretion and balance are recalled. Dietary factors, especially lactose and other milk components, influencing calcium bioavailability at intestinal and renal levels are reviewed. A critical examination of all the methods used for evaluating calcium bioavailability is made. This includes in vitro assays, classical and isotopic balances, urinary excretion, isotope labeling in the urine, plasma and bones, long term evaluation of bone mineralization and the use of biological bone markers. Importance and advantages of animal models are discussed. The state of the art in the comparative bioavailability of calcium in foods is detailed including a comparison of sources of calcium (dairy products and calcium salts) in human studies and in some animal studies, casein phosphopeptides, proteins, lactose and lactase and their relation with calcium bioavailability (in humans and rats). An update on the consumption of dairy products and bone mass is presented. Emphasis on peculiarities and advantages of calcium in milk and dairy products is given. PMID:10759138

  7. Thiosulfate Reduces Calcium Phosphate Nephrolithiasis

    PubMed Central

    Asplin, John R.; Donahue, Susan E.; Lindeman, Christina; Michalenka, Anne; Strutz, Kelly Laplante; Bushinsky, David A.

    2009-01-01

    An uncontrolled trial reported that sodium thiosulfate reduces formation of calcium kidney stones in humans, but this has not been established in a controlled human study or animal model. Using the genetic hypercalciuric rat, an animal model of calcium phosphate stone formation, we studied the effect of sodium thiosulfate on urine chemistries and stone formation. We fed genetic hypercalciuric rats normal food with or without sodium thiosulfate for 18 wk and measured urine chemistries, supersaturation, and the upper limit of metastability of urine. Eleven of 12 untreated rats formed stones compared with only three of 12 thiosulfate-treated rats (P < 0.002). Urine calcium and phosphorus were higher and urine citrate and volume were lower in the thiosulfate-treated rats, changes that would increase calcium phosphate supersaturation. Thiosulfate treatment lowered urine pH, which would lower calcium phosphate supersaturation. Overall, there were no statistically significant differences in calcium phosphate supersaturation or upper limit of metastability between thiosulfate-treated and control rats. In vitro, thiosulfate only minimally affected ionized calcium, suggesting a mechanism of action other than calcium chelation. In summary, sodium thiosulfate reduces calcium phosphate stone formation in the genetic hypercalciuric rat. Controlled trials testing the efficacy and safety of sodium thiosulfate for recurrent kidney stones in humans are needed. PMID:19369406

  8. The transport of chloride in Ehrlich ascites tumor cells.

    PubMed

    Levinson, C; Villereal, M L

    1976-06-01

    The steady state transport and distribution of chloride between the intracellular and extracellular phases was investigated when the extracellular chloride concentration was varied by isosmotic replacement with nitrate, bromide and acetate. The results of these experiments show that chloride transport, measured by uptake of 36Cl, is sensitive to the replacement anion. In the presence of nitrate, chloride transport is a linear function of the extracellular chloride concentration. The relationship between chloride transport and extracellular chloride in the presence of bromide is concave upward which suggests that this anion inhibits chloride movement. However, when acetate replaces chloride, the relationship between chloride transport and extracellular chloride is concave downward. The chloride distribution ratio of cells incubated in 145-155mM chloride medium is 0.386 and is not effected by the replacement of chloride with nitrate, bromide or acetate. These findings are consistent with the assertion that chloride transport is composed of two parallel pathways, a diffusional plus a saturating, mediated component. Of the total chloride flux (9.1 mmoles Cl-/kg dry weight per minute) measured in chloride medium (145-155 mM Cl-), the mediated component represents 40% and the diffusional component 60%. PMID:1270521

  9. Control of spontaneous firing patterns by the selective coupling of calcium currents to calcium-activated potassium currents in striatal cholinergic interneurons.

    PubMed

    Goldberg, Joshua A; Wilson, Charles J

    2005-11-01

    The spontaneous firing patterns of striatal cholinergic interneurons are sculpted by potassium currents that give rise to prominent afterhyperpolarizations (AHPs). Large-conductance calcium-activated potassium (BK) channel currents contribute to action potential (AP) repolarization; small-conductance calcium-activated potassium channel currents generate an apamin-sensitive medium AHP (mAHP) after each AP; and bursts of APs generate long-lasting slow AHPs (sAHPs) attributable to apamin-insensitive currents. Because all these currents are calcium dependent, we conducted voltage- and current-clamp whole-cell recordings while pharmacologically manipulating calcium channels of the plasma membrane and intracellular stores to determine what sources of calcium activate the currents underlying AP repolarization and the AHPs. The Cav2.2 (N-type) blocker omega-conotoxin GVIA (1 microM) was the only blocker that significantly reduced the mAHP, and it induced a transition to rhythmic bursting in one-third of the cells tested. Cav1 (L-type) blockers (10 microM dihydropyridines) were the only ones that significantly reduced the sAHP. When applied to cells induced to burst with apamin, dihydropyridines reduced the sAHPs and abolished bursting. Depletion of intracellular stores with 10 mM caffeine also significantly reduced the sAHP current and reversibly regularized firing. Application of 1 microM omega-conotoxin MVIIC (a Cav2.1/2.2 blocker) broadened APs but had a negligible effect on APs in cells in which BK channels were already blocked by submillimolar tetraethylammonium chloride, indicating that Cav2.1 (Q-type) channels provide the calcium to activate BK channels that repolarize the AP. Thus, calcium currents are selectively coupled to the calcium-dependent potassium currents underlying the AHPs, thereby creating mechanisms for control of the spontaneous firing patterns of these neurons. PMID:16267230

  10. Measurement of calcium transients and slow calcium current in myotubes

    PubMed Central

    1994-01-01

    The purpose of this study was to characterize excitation-contraction (e- c) coupling in myotubes for comparison with e-c coupling of adult skeletal muscle. The whole cell configuration of the patch clamp technique was used in conjunction with the calcium indicator dye Fluo-3 to study the calcium transients and slow calcium currents elicited by voltage clamp pulses in cultured myotubes obtained from neonatal mice. Cells were held at -80 mV and stimulated with 15-20 ms test depolarizations preceded and followed by voltage steps designed to isolate the slow calcium current. The slow calcium current had a threshold for activation of about 0 mV; the peak amplitude of the current reached a maximum at 30 to 40 mV a and then declined for still stronger depolarizations. The calcium transient had a threshold of about -10 mV, and its amplitude increased as a sigmoidal function of test potential and did not decrease again even for test depolarizations sufficiently strong (> or = 50 mV) that the amplitude of the slow calcium current became very small. Thus, the slow calcium current in myotubes appears to have a negligible role in the process of depolarization-induced release of intracellular calcium and this process in myotubes is essentially like that in adult skeletal muscle. After repolarization, however, the decay of the calcium transient in myotubes was very slow (hundreds of ms) compared to adult muscle, particularly after strong depolarizations that triggered larger calcium transients. Moreover, when cells were repolarized after strong depolarizations, the transient typically continued to increase slowly for up to several tens of ms before the onset of decay. This continued increase after repolarization was abolished by the addition of 5 mM BAPTA to the patch pipette although the rapid depolarization-induced release was not, suggesting that the slow increase might be a regenerative response triggered by the depolarization-induced release of calcium. The addition of either 0.5 mM Cd2+ + 0.1 mM La3+ or the dihydropyridine (+)-PN 200-110 (1 microM) reduced the amplitude of the calcium transient by mechanisms that appeared to be unrelated to the block of current that these agents produce. In the majority of cells, the decay of the transient was accelerated by the addition of the heavy metals or the dihydropyridine, consistent with the idea that the removal system becomes saturated for large calcium releases and becomes more efficient when the size of the release is reduced. PMID:8169594

  11. 21 CFR 182.8217 - Calcium phosphate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2009-04-01 true Calcium phosphate. 182.8217 Section 182.8217 Food...RECOGNIZED AS SAFE Nutrients § 182.8217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  12. 21 CFR 182.1217 - Calcium phosphate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Calcium phosphate. 182.1217 Section 182.1217 Food...Purpose GRAS Food Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  13. 21 CFR 182.8217 - Calcium phosphate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Calcium phosphate. 182.8217 Section 182.8217 Food...RECOGNIZED AS SAFE Nutrients § 182.8217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  14. 21 CFR 182.1217 - Calcium phosphate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Calcium phosphate. 182.1217 Section 182.1217 Food...Purpose GRAS Food Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  15. 21 CFR 582.6197 - Calcium diacetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Calcium diacetate. 582.6197 Section 582.6197...RECOGNIZED AS SAFE Sequestrants 2 § 582.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  16. 21 CFR 172.715 - Calcium lignosulfonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 3 2012-04-01 2012-04-01 false Calcium lignosulfonate. 172.715 Section 172.715... Other Specific Usage Additives § 172.715 Calcium lignosulfonate. Calcium lignosulfonate may be safely used in or on...

  17. 21 CFR 582.6197 - Calcium diacetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Calcium diacetate. 582.6197 Section 582.6197...RECOGNIZED AS SAFE Sequestrants 2 § 582.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  18. 21 CFR 182.6197 - Calcium diacetate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Calcium diacetate. 182.6197 Section 182.6197...RECOGNIZED AS SAFE Sequestrants 1 § 182.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  19. 21 CFR 182.6197 - Calcium diacetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...3 2010-04-01 2009-04-01 true Calcium diacetate. 182.6197 Section 182.6197...RECOGNIZED AS SAFE Sequestrants 1 § 182.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  20. 21 CFR 182.6197 - Calcium diacetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Calcium diacetate. 182.6197 Section 182.6197...RECOGNIZED AS SAFE Sequestrants 1 § 182.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  1. 21 CFR 182.6197 - Calcium diacetate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Calcium diacetate. 182.6197 Section 182.6197...RECOGNIZED AS SAFE Sequestrants 1 § 182.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  2. 21 CFR 172.715 - Calcium lignosulfonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 3 2013-04-01 2013-04-01 false Calcium lignosulfonate. 172.715 Section 172.715... Other Specific Usage Additives § 172.715 Calcium lignosulfonate. Calcium lignosulfonate may be safely used in or on...

  3. 21 CFR 182.6197 - Calcium diacetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Calcium diacetate. 182.6197 Section 182.6197...RECOGNIZED AS SAFE Sequestrants 1 § 182.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  4. 21 CFR 172.720 - Calcium lactobionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Calcium lactobionate. 172.720 Section 172...Other Specific Usage Additives § 172.720 Calcium lactobionate. The food additive calcium lactobionate may be safely used in food...

  5. 21 CFR 582.6197 - Calcium diacetate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Calcium diacetate. 582.6197 Section 582.6197...RECOGNIZED AS SAFE Sequestrants 2 § 582.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  6. 21 CFR 172.720 - Calcium lactobionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Calcium lactobionate. 172.720 Section 172...Other Specific Usage Additives § 172.720 Calcium lactobionate. The food additive calcium lactobionate may be safely used in food...

  7. 21 CFR 582.6199 - Calcium gluconate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 2014-04-01 false Calcium gluconate. 582.6199 Section 582.6199...RECOGNIZED AS SAFE Sequestrants 2 § 582.6199 Calcium gluconate. (a) Product. Calcium gluconate. (b) Conditions of use....

  8. 21 CFR 172.720 - Calcium lactobionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Calcium lactobionate. 172.720 Section 172...Other Specific Usage Additives § 172.720 Calcium lactobionate. The food additive calcium lactobionate may be safely used in food...

  9. 21 CFR 582.6199 - Calcium gluconate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2010-04-01 false Calcium gluconate. 582.6199 Section 582.6199...RECOGNIZED AS SAFE Sequestrants 2 § 582.6199 Calcium gluconate. (a) Product. Calcium gluconate. (b) Conditions of use....

  10. 21 CFR 582.6197 - Calcium diacetate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2010-04-01 false Calcium diacetate. 582.6197 Section 582.6197...RECOGNIZED AS SAFE Sequestrants 2 § 582.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  11. 21 CFR 582.6197 - Calcium diacetate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Calcium diacetate. 582.6197 Section 582.6197...RECOGNIZED AS SAFE Sequestrants 2 § 582.6197 Calcium diacetate. (a) Product. Calcium diacetate. (b) Conditions of use....

  12. 21 CFR 172.715 - Calcium lignosulfonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 3 2011-04-01 2011-04-01 false Calcium lignosulfonate. 172.715 Section 172.715... Other Specific Usage Additives § 172.715 Calcium lignosulfonate. Calcium lignosulfonate may be safely used in or on...

  13. 21 CFR 172.720 - Calcium lactobionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Calcium lactobionate. 172.720 Section 172...Other Specific Usage Additives § 172.720 Calcium lactobionate. The food additive calcium lactobionate may be safely used in food...

  14. 21 CFR 172.715 - Calcium lignosulfonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 3 2014-04-01 2014-04-01 false Calcium lignosulfonate. 172.715 Section 172.715... Other Specific Usage Additives § 172.715 Calcium lignosulfonate. Calcium lignosulfonate may be safely used in or on...

  15. 21 CFR 582.6199 - Calcium gluconate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2011-04-01 2011-04-01 false Calcium gluconate. 582.6199 Section 582.6199...RECOGNIZED AS SAFE Sequestrants 2 § 582.6199 Calcium gluconate. (a) Product. Calcium gluconate. (b) Conditions of use....

  16. 21 CFR 172.720 - Calcium lactobionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 2010-04-01 2009-04-01 true Calcium lactobionate. 172.720 Section 172...Other Specific Usage Additives § 172.720 Calcium lactobionate. The food additive calcium lactobionate may be safely used in food...

  17. 21 CFR 582.6199 - Calcium gluconate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 2012-04-01 false Calcium gluconate. 582.6199 Section 582.6199...RECOGNIZED AS SAFE Sequestrants 2 § 582.6199 Calcium gluconate. (a) Product. Calcium gluconate. (b) Conditions of use....

  18. 21 CFR 582.6199 - Calcium gluconate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 2013-04-01 false Calcium gluconate. 582.6199 Section 582.6199...RECOGNIZED AS SAFE Sequestrants 2 § 582.6199 Calcium gluconate. (a) Product. Calcium gluconate. (b) Conditions of use....

  19. 21 CFR 172.715 - Calcium lignosulfonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 3 2010-04-01 2009-04-01 true Calcium lignosulfonate. 172.715 Section 172.715... Other Specific Usage Additives § 172.715 Calcium lignosulfonate. Calcium lignosulfonate may be safely used in or on...

  20. Alterations of Extracellular Calcium Elicit Selective Modes of Cell Death and Protease Activation in SH-SY5Y Human Neuroblastoma Cells

    Microsoft Academic Search

    Kim M. McGinnis; Kevin K. W. Wang; Margaret E. Gnegy

    2008-01-01

    The role of intracellular Ca21 homeostasis in mechanisms of neuronal cell death and cysteine protease activation was investigated in SH-SY5Y human neuro- blastoma cells. Cells were incubated in 2 mM EGTA to lower intracellular Ca21 or 5m M CaCl2 to raise it. Cell death and activation of calpain and caspase-3 were mea- sured. Both EGTA and excess CaCl2 elicited cell

  1. Phenomics of Cardiac Chloride Channels

    PubMed Central

    Duan, Dayue Darrel

    2014-01-01

    Forward genetic studies have identified several chloride (Cl?) channel genes, including CFTR, ClC-2, ClC-3, CLCA, Bestrophin, and Ano1, in the heart. Recent reverse genetic studies using gene targeting and transgenic techniques to delineate the functional role of cardiac Cl? channels have shown that Cl? channels may contribute to cardiac arrhythmogenesis, myocardial hypertrophy and heart failure, and cardioprotection against ischemia reperfusion. The study of physiological or pathophysiological phenotypes of cardiac Cl? channels, however, is complicated by the compensatory changes in the animals in response to the targeted genetic manipulation. Alternatively, tissue-specific conditional or inducible knockout or knockin animal models may be more valuable in the phenotypic studies of specific Cl? channels by limiting the effect of compensation on the phenotype. The integrated function of Cl? channels may involve multiprotein complexes of the Cl? channel subproteome. Similar phenotypes can be attained from alternative protein pathways within cellular networks, which are influenced by genetic and environmental factors. The phenomics approach, which characterizes phenotypes as a whole phenome and systematically studies the molecular changes that give rise to particular phenotypes achieved by modifying the genotype under the scope of genome/proteome/phenome, may provide more complete understanding of the integrated function of each cardiac Cl? channel in the context of health and disease. PMID:23720326

  2. 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.

  3. Corrosion behaviors of materials in aluminum chloride–1-ethyl-3-methylimidazolium chloride ionic liquid

    Microsoft Academic Search

    Chien-Hsiung Tseng; Jeng-Kuei Chang; Jhen-Rong Chen; W. T. Tsai; Ming-Jay Deng; I-Wen Sun

    2010-01-01

    The corrosion properties of carbon steel (CS), 304 stainless steel (304 SS), and pure titanium (Ti) are first studied in aluminum chloride–1-ethyl-3-methylimidazolium chloride ionic liquid (IL). An active-to-passive transition behavior was clearly observed for CS. The 304 SS exhibited the best stability among the materials; no considerable corrosion was recognized even in this high-chloride environment. In contrast, although Ti resists

  4. Influence of voltage on chloride diffusion coefficients from chloride migration tests

    SciTech Connect

    McGrath, P.F.; Hooton, R.D. [Univ. of Toronto, Ontario (Canada). Dept. of Civil Engineering] [Univ. of Toronto, Ontario (Canada). Dept. of Civil Engineering

    1996-08-01

    A chloride migration test method is described and test results are given for concrete subjected to a range of potential gradients. A method for setting the potential across the sample length using reference electrodes and Luggin capillaries is described. Apparent and effective diffusion coefficients were calculated from chloride break-through time and steady state chloride flux respectively at each potential. Accounting for polarization and IR drop losses is significant particularly at lower applied potentials.

  5. Reductive Dechlorination of the Vinyl Chloride Surrogate

    E-print Network

    Semprini, Lewis

    , microbial transformation of TCE results in the accumulation of vinyl chloride (VC), a known carcinogen with PVC manufacturing. In addition, accumulation of VC, a known carcinogen (2), is sometimes observed

  6. Catastrophic event modeling. [lithium thionyl chloride batteries

    NASA Technical Reports Server (NTRS)

    Frank, H. A.

    1981-01-01

    A mathematical model for the catastrophic failures (venting or explosion of the cell) in lithium thionyl chloride batteries is presented. The phenomenology of the various processes leading to cell failure is reviewed.

  7. Microencapsulation of potassium chloride with mastic.

    PubMed

    Georgarakis, M; Gröning, R; Henzler, P

    1987-07-01

    The present investigation deals with the microencapsulation of potassium chloride with mastic. Spherical potassium chloride crystals with a mean particle diameter of approximately 450 microns were used. It could be shown that with a layer of mastic wall material thicker than 21 microns the release of potassium chloride in the in vitro test can be controlled for more than 6 h. The thickness of the wall material over the tested range of 21 to 33 microns has only a limited effect on the kinetics of release of potassium chloride. Increasing the thickness of the layer from 21 to 33 microns merely leads to a reduction of about another 10% in the amount of drug released in 6 h. PMID:3671470

  8. Reactions of polyfluoroalkenylsulfenyl chlorides with carbonyl compounds

    Microsoft Academic Search

    A. N. Kovregin; A. Yu. Sizov; A. F. Ermolov; A. F. Kolomiets

    2000-01-01

    Polyfluorinated 1-fluoroalk-1-enylsulfenyl chlorides react with ketones RCOCH2R? to give unsaturated sulfides. The latter undergo smooth cyclization into 2-alkylidene-1,3-oxathioles in the presence of\\u000a BF3NEt3.

  9. Adsorption and photocatalytic degradation of dyes on polyacrylamide/calcium alginate/TiO2 composite film

    NASA Astrophysics Data System (ADS)

    Wei, Shuxin; Zhao, Kongyin; Zhang, Xinxin; Fu, Yifan; Li, Zhihui; Xu, Sai; Wei, Junfu

    2015-03-01

    A casting solution was prepared by dispersing titanium dioxide (TiO2) nanoparticles in the sodium alginate and acrylamide aqueous solution. The casting solution was spread on a glass plate by a glass rod enlaced with brass wires to control the thickness of the sticky solution. Then polyacrylamide/calcium alginate/TiO2 (PAM/CA/T) composite film was obtained after UV irradiation and cross-linking by CaCl2. The PAM/CA/T film was characterized by scanning electron microscope and transmission electron microscope. The PAM/CA/T film had good strength and toughness. And they did not rupture after swelling in 5 wt.% NaCl solution and still had good mechanical properties. The adsorption properties of the PAM/CA/T film were investigated by using different dyes as the adsorbates. The photocatalytic degradation properties of these dyes on the PAM/CA/T films were also researched. The results indicated that there was no difference in the adsorption efficiency of PAM/CA film and PAM/CA/T-30 film. The adsorption rates of all the dyes were fast. The pre-adsorption of dyes had little effect on the catalytic degradation of dyes on PAM/CA/T film. The PAM/CA/T hydrogel film provided a suitable carrier for TiO2 in the photocatalytic degradation of dyes and the degradation efficiency of PAM/CA/T-30 film for methyl orange reached 80.76%. The PAM/CA/T film had good reusability and could degrade dyes in NaCl solution.

  10. The Aspergillus giganteus antifungal protein AFPNN5353 activates the cell wall integrity pathway and perturbs calcium homeostasis

    PubMed Central

    2011-01-01

    Background The antifungal protein AFPNN5353 is a defensin-like protein of Aspergillus giganteus. It belongs to a group of secretory proteins with low molecular mass, cationic character and a high content of cysteine residues. The protein inhibits the germination and growth of filamentous ascomycetes, including important human and plant pathogens and the model organsims Aspergillus nidulans and Aspergillus niger. Results We determined an AFPNN5353 hypersensitive phenotype of non-functional A. nidulans mutants in the protein kinase C (Pkc)/mitogen-activated protein kinase (Mpk) signalling pathway and the induction of the ?-glucan synthase A (agsA) promoter in a transgenic A. niger strain which point at the activation of the cell wall integrity pathway (CWIP) and the remodelling of the cell wall in response to AFPNN5353. The activation of the CWIP by AFPNN5353, however, operates independently from RhoA which is the central regulator of CWIP signal transduction in fungi. Furthermore, we provide evidence that calcium (Ca2+) signalling plays an important role in the mechanistic function of this antifungal protein. AFPNN5353 increased about 2-fold the cytosolic free Ca2+ ([Ca2+]c) of a transgenic A. niger strain expressing codon optimized aequorin. Supplementation of the growth medium with CaCl2 counteracted AFPNN5353 toxicity, ameliorated the perturbation of the [Ca2+]c resting level and prevented protein uptake into Aspergillus sp. cells. Conclusions The present study contributes new insights into the molecular mechanisms of action of the A. giganteus antifungal protein AFPNN5353. We identified its antifungal activity, initiated the investigation of pathways that determine protein toxicity, namely the CWIP and the Ca2+ signalling cascade, and studied in detail the cellular uptake mechanism in sensitive target fungi. This knowledge contributes to define new potential targets for the development of novel antifungal strategies to prevent and combat infections of filamentous fungi which have severe negative impact in medicine and agriculture. PMID:21943024

  11. Self-assembled titanium calcium oxide nanopatterns as versatile reactive nanomasks for dry etching lithographic transfer with high selectivity

    NASA Astrophysics Data System (ADS)

    Faustini, Marco; Drisko, Glenna L.; Letailleur, Alban A.; Montiel, Rafael Salas; Boissière, Cédric; Cattoni, Andrea; Haghiri-Gosnet, Anne Marie; Lerondel, Gilles; Grosso, David

    2013-01-01

    We report the simple preparation of ultra-thin self-assembled nanoperforated titanium calcium oxide films and their use as reactive nanomasks for selective dry etching of silicon. This novel reactive nanomask is composed of TiO2 in which up to 50% of Ti was replaced by Ca (CaxTi(1-x)O(2-x)). The system was prepared by evaporation induced self-assembly of dip-coated solution of CaCl2, TiCl4 and poly(butadiene-block-ethylene oxide) followed by 5 min of thermal treatment at 500 °C in air. The mask exhibits enhanced selectivity by forming a CaF2 protective layer in the presence of a chemically reactive fluorinated plasma. In particular it is demonstrated that ordered nano-arrays of dense Si pillars, or deep cylindrical wells, with high aspect ratio i.e. lateral dimensions as small as 20 nm and height up to 200 nm, can be formed. Both wells and pillars were formed by tuning the morphology and the homogeneity of the deposited mask. The mask preparation is extremely fast and simple, low-cost and easily scalable. Its combination with reactive ion etching constitutes one of the first examples of what can be achieved when sol-gel chemistry is coupled with top-down technologies. The resulting Si nanopatterns and nanostructures are of high interest for applications in many fields of nanotechnology including electronics and optics. This work extends and diversifies the toolbox of nanofabrication methods.

  12. Molecular Structure of Calcium Sulfide

    NSDL National Science Digital Library

    2003-06-03

    Calcium sulfide in pure form is white and shaped like cubic crystals, and is slightly soluble in water. This is used as a base for luminescent materials. Calcium sulfide is also known as hepar calcies; sulfurated lime. This substance is used in phosphors and as a direct fungicide on powdery mildews and insecticides.

  13. 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)

  14. 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)

  15. Effect of chemical admixtures on properties of high-calcium fly ash geopolymer

    NASA Astrophysics Data System (ADS)

    Rattanasak, Ubolluk; Pankhet, Kanokwan; Chindaprasirt, Prinya

    2011-06-01

    Owing to the high viscosity of sodium silicate solution, fly ash geopolymer has the problems of low workability and rapid setting time. Therefore, the effect of chemical admixtures on the properties of fly ash geopolymer was studied to overcome the rapid set of the geopolymer in this paper. High-calcium fly ash and alkaline solution were used as starting materials to synthesize the geopolymer. Calcium chloride, calcium sulfate, sodium sulfate, and sucrose at dosages of 1wt% and 2wt% of fly ash were selected as admixtures based on concrete knowledge to improve the properties of the geopolymer. The setting time, compressive strength, and degree of reaction were recorded, and the microstructure was examined. The results show that calcium chloride significantly shortens both the initial and final setting times of the geopolymer paste. In addition, sucrose also delays the final setting time significantly. The degrees of reaction of fly ash in the geopolymer paste with the admixtures are all higher than those of the control paste. This contributes to the obvious increases in compressive strength.

  16. [Simultaneous determination of calcium and magnesium in urines by flame atomic absorption spectrometry].

    PubMed

    Bai, Yu; Ouyang, Jian-Ming; Bai, Yan; Chen, Mei-Luan

    2004-08-01

    The contents of calcium and magnesium in urines were simultaneously determined by flame atomic absorption spectrometry. The optimized working conditions were ascertained. For the determination of calcium, the used wavelength was 422.8 nm, and the current of HCL(Hollow Cathode Lamp) was 3 mA; for the determination of magnesium, the used wavelength was 285.2 nm, and the current of HCL (Hollow Cathode Lamp) was 4 mA. The height of burner and the air-acetylene ratio were 8 mm and 6:1, respectively, for the determination of both calcium and magnesium. In order to remove the disturbance of phosphate, sulphate and silicate on the determination of calcium, a releasing reagent can be used. Lanthanum chloride (LaCl3) was tested as a better releasing reagent than strontium chloride (SrCl2). The disturbance of urinary substrate could be avoided after the urines were diluted to 1:100 with distilled water. The concentrations of Ca and Mg in 15 urines were determined under the optimized conditions. The obtained results were consistent with the archived data. The recovery was 96%-104%, the relative standard deviation for a sample was 1.8% with P < 0.05. PMID:15766134

  17. Membrane potential, chloride exchange, and chloride conductance in Ehrlich mouse ascites tumour cells.

    PubMed Central

    Hoffmann, E K; Simonsen, L O; Sjøholm, C

    1979-01-01

    1. The steady-state tracer exchange flux of chloride was measured at 10-150 mM external chloride concentration, substituting either lactate or sucrose for chloride. The chloride flux saturates in both cases with a K 1/2 about 50 and 15 mM, respectively. 2. The inhibitory effect of other monovalent anions on the chloride transport was investigated by measuring the 36Cl- efflux into media where either bromide, nitrate, or thiocyanate had been substituted for part of the chloride. The sequence of increasing affinity for the chloride transport system was found to be: Br- less than Cl- less than SCN- = NO3-. 3. The chloride steady-state exchange flux in the presence of nitrate can be described by Michaelis-Menten kinetics with nitrate as a competitive inhibitor of the chloride flux. 4. The apparent activation energy (EA) was determined to be 67 +/- 6.2 kJ/mole, and was constant between 7 and 38 degrees C. 5. The membrane potential (Vm) was measured as a function of the concentration of external K+, substituting K+ for Na+. The transference number of K+ (tK) was estimated from the slope of Vm vs. log10 (K+)e, and tCl and tNa were calculated, neglecting current carried by ions other than Cl-, K+, and Na+. The diffusional net flux of K+ was calculated from the steady-state exchange flux of 42K+, assuming the flux ratio equation to be valid. From this value the K+ conductance and the Na+ and Cl- conductances were calculated. The experiments showed that GCl, GNa, and GK are all about 14 muS/cm2. 6. The net (conductive) chloride permeability derived from the chloride conductance was 4 x 10(-8) cm/sec compared with the apparent permeability of 6 x 10(-7) cm/sec as calculated from the chloride tracer exchange flux. These data suggest that about 95% of the chloride transport is mediated by an electrically silent exchange diffusion. 7. Comparable effects of phloretin (0.25 mM) on the net (conductive) permeability and the apparent permeability to chloride (about 80% inhibition) may indicate that the chloride exchange and conductance pathways are not completely separate and distinct modes of transport, but may involve common elements. The reduced chloride permeability in the presence of phloretin is estimated to be two orders of magnitude larger than the ground permeability of the cell membrane. PMID:529133

  18. Reactions of polyfluoroalkylsulfenyl chlorides with phenols

    Microsoft Academic Search

    A. Yu. Sizov; A. F. Kolomiets; A. V. Fokin

    1991-01-01

    Polyfluoroalkylsulfenyl chlorides thiolate phenol and its ortho- and meta-substituted derivatives regiospecifically at the para-position in the absence of a catalyst and of a hydrogen chloride acceptor. Ortho thiolation occurs with significantly greater difficulty in the para-substituted phenols, and is only possible with the strong electron-donor properties of the substituent. Polyfluoroalkylthiolation of phenols is rendered more difficult with the increase in

  19. Copper chloride cathode for a secondary battery

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (inventor); Distefano, Salvador (inventor); Nagasubramanian, Ganesan (inventor); Bankston, Clyde P. (inventor)

    1990-01-01

    Higher energy and power densities are achieved in a secondary battery based on molten sodium and a solid, ceramic separator such as a beta alumina and a molten catholyte such as sodium tetrachloroaluminate and a copper chloride cathode. The higher cell voltage of copper chloride provides higher energy densities and the higher power density results from increased conductivity resulting from formation of copper as discharge proceeds.

  20. Inhibition of epithelial chloride channels by cytosol

    Microsoft Academic Search

    K. Kunzelmann; M. Tilmann; Ch. P. Hansen; R. Greger

    1991-01-01

    Chloride channels that have an intermediate conductance and are outwardly rectifying were studied by the patch-clamp technique in cell-excised membrane patches from respiratory epithelial cells in primary culture (REC) of normal and cystic fibrosis tissue, HT29 and T84 human colon carcinoma cells and placenta trophoblast cells (PTC). Chloride channels were immediately activated by the exposure of the cytosolic side of