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Sample records for chlorine potassium calcium

  1. Elements from chlorine to calcium nuclear reactions

    CERN Document Server

    Kunz, Wunibald

    1968-01-01

    Nuclear Tables: Part II Nuclear Reactions, Volume 3: The Elements from Chlorine to Calcium contains tabulations of the nuclear reaction values of elements chlorine, argon, potassium, and calcium. These tabulations provide the calculated Q-values of the elements and their isotopes. This book will be of value to general chemistry researchers.

  2. Potassium chloride production by microcline chlorination

    International Nuclear Information System (INIS)

    Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl2–N2 mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated

  3. Potassium chloride production by microcline chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Orosco, Pablo, E-mail: porosco@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina); Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, San Luis (Argentina); Ruiz, María del Carmen [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina)

    2015-08-10

    Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl{sub 2}–N{sub 2} mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated.

  4. Effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Chlorine content and position of chlorinated phenols have many significant effects on the reactivity of oxido-reduction. The effects of chlorine content and position of chlorinated phenols on their oxidation kinetics by potassium permanganate were evaluated through different kinetics studies. Since chlorine was an electron withdrawing atom, the substitution of chlorine on the aromatic ring decreased the oxidation rate constant by σ-electron withdrawing conductive effect; at the same time, the substitution of chlorine at ortho or para position on the aromatic ring increased the oxidation rate constant by π-electron donating conjugative effect, and the conjugative effect could counteract the negative impact of the conductive effect to some extent. On the other hand, the substitution of chlorine at ortho position on the aromatic ring decreased the oxidation rate constant by steric hindrance effect. The oxidation rate constants of phenol and chlorinated phenols studied decreased as follow order: 4-chlorophenol>2,4-dichlorophenol>phenol>2,6-dichlorophenol.

  5. Calcium, magnesium, and potassium in food

    Science.gov (United States)

    The biochemical and physiological functions and consequences of deficient intakes, which show the nutritional importance of calcium, magnesium and potassium for humans, are reviewed. The dietary recommendations and food sources for these essential mineral elements for humans are presented. Factors t...

  6. Adsorption of Potassium and Calcium Ions by Variable Charge Soils

    Institute of Scientific and Technical Information of China (English)

    LIHONG-YAN; JIGUO-LIANG

    1992-01-01

    Interactions of potassium and calcium ions with four typical variable charge soils in South China were examined by measuring pK-0.5pCa value with a potassium ion-selective electrode and a calcium ion-selective electrode,and pK value with a potassium ion-selective electrode.The results showed that adsorption of potassium and calcium ions increased with soil suspension pH,and the tendency of the pK-0.5pCa value changing with pH differed with respect to pH range and potassium to calcium ratio.Adsorption of equal amount of calcium and potassium ions led to release of an identical number of protons,suggesting similar adsorption characteristics of these two ions when adsorbed by variable charge soils.Compared with red soil,latosol and lateritic red soil had higher adsorption selectivities for calcium ion.The red soil had a greater affinity for potassium ion than that for calcium ion at low concentration,which seems to result from its possession of 2:1 type minerals,such as vermiculite and mica with a high affinity for potassium ion.The results indicated that adsorption of potassium and calcium ions by the variable charge soils was chiefly caused by the electrostatic attraction between the cations and the soil surfaces.Moreover,it was found that sulfate could affect the adsorption by changing soil surface properties and by forming ion-pair.

  7. "Caged calcium" in Aplysia pacemaker neurons. Characterization of calcium-activated potassium and nonspecific cation currents

    OpenAIRE

    1989-01-01

    We have studied calcium-activated potassium current, IK(Ca), and calcium-activated nonspecific cation current, INS(Ca), in Aplysia bursting pacemaker neurons, using photolysis of a calcium chelator (nitr-5 or nitr-7) to release "caged calcium" intracellularly. A computer model of nitr photolysis, multiple buffer equilibration, and active calcium extrusion was developed to predict volume-average and front-surface calcium concentration transients. Changes in arsenazo III absorbance were used to...

  8. Chlorination of calcium tungstate by mixture of chlorine and sulfur dioxide

    International Nuclear Information System (INIS)

    Results of thermodynamic calculations and experimental investigations of interaction of calcium tungstate with Cl2+SO2 mixture at 400-850 deg C are presented. It is shown that the processes passes through several sequential and parallel stages with formation of tungsten (6) oxide and calcium chloride as intermediate products. Peculiarities of the process are determined by the ratio of rates of WO3 formation and chlorination stages

  9. Gas Phase Sulfur, Chlorine and Potassium Chemistry in Biomass Combustion

    DEFF Research Database (Denmark)

    Løj, Lusi Hindiyarti

    2007-01-01

    Gas Phase Sulfur, Chlorine and Alkali Metal Chemistry in Biomass Combustion Concern about aerosols formation, deposits, corrosion, and gaseous emissions during biomass combustion, especially straw, continues to be a driving force for investigation on S, Cl, K-containing species under combustions...... uncertainties. In the present work, the detailed kinetic model for gas phase sulfur, chlorine, alkali metal, and their interaction has been updated. The K/O/H/Cl chemistry, S chemistry, and their interaction can reasonably predict a range of experimental data. In general, understanding of the interaction...... sulfur chemistry important for the SO2/SO3 ratio under combustion conditions has been updated. The uncertainties of the important rate constants have been minimized. Modeling predictions with a revised reaction mechanism for SO2/SO3 chemistry are in a good agreement with a range of experimental data from...

  10. Internal detection of surface plasmon coupled chemiluminescence during chlorination of potassium thin films

    Science.gov (United States)

    Becker, Felix; Krix, David; Hagemann, Ulrich; Nienhaus, Hermann

    2013-01-01

    The interaction of chlorine with potassium surfaces is a prototype reaction with a strong non-adiabatic energy transfer leading to exoemission and chemiluminescence. Thin film K/Ag/p-Si(111) Schottky diodes with 8 nm potassium on a 5-200 nm thick Ag layer are used as 2π-photodetectors for the chemiluminescence during chlorination of the K film at 110 K. The observed photocurrent shows a sharp maximum for small exposures and decreases gradually with the increasing chloride layer. The time dependence can be explained by the reaction kinetics, which is governed initially by second-order adsorption processes followed by an electric field-assisted diffusion. The detector current corresponds to a yield of a few percent of elementary charge per reacting chlorine molecule and is orders of magnitude larger than for external detection. The photoyield can be enhanced by increasing the Ag film thickness. For Ag films of 30 and 50 nm, the yield exhibits a maximum indicating surface plasmon coupled chemiluminescence. Surface plasmon polaritons in the Ag layer are excited by the reaction and decay radiatively into Si leading to the observed currents. A model calculation for the reverse process in attenuated total reflection is applied to explain the observed current yield maxima.

  11. Oxidative Stress and Maxi Calcium-Activated Potassium (BK Channels

    Directory of Open Access Journals (Sweden)

    Anton Hermann

    2015-08-01

    Full Text Available All cells contain ion channels in their outer (plasma and inner (organelle membranes. Ion channels, similar to other proteins, are targets of oxidative impact, which modulates ion fluxes across membranes. Subsequently, these ion currents affect electrical excitability, such as action potential discharge (in neurons, muscle, and receptor cells, alteration of the membrane resting potential, synaptic transmission, hormone secretion, muscle contraction or coordination of the cell cycle. In this chapter we summarize effects of oxidative stress and redox mechanisms on some ion channels, in particular on maxi calcium-activated potassium (BK channels which play an outstanding role in a plethora of physiological and pathophysiological functions in almost all cells and tissues. We first elaborate on some general features of ion channel structure and function and then summarize effects of oxidative alterations of ion channels and their functional consequences.

  12. Study of Cold Potassium Atom - Calcium Ion Reactions

    Science.gov (United States)

    Egodapitiya, Kisra; Gang, Shu; Clark, Robert; Brown, Kenneth

    2016-05-01

    We report on our progress towards constructing a hybrid system for studying reactions between cold Potassium (K) atoms and cold Calcium (Ca+) ions. Ca+ ions will be trapped and Doppler-cooled inside a linear quadrupole ion trap. Cold K atoms will be created inside a magneto optical trap, such that the ion and the atoms are in an overlapping volume. Trapping and re-pumping beams for the Potassium MOT are derived from the same laser with wavelength 766 nm using two acousto optic modulators. The reaction products will be detected using a time-of- flight mass spectrometer that is designed to detect radially ejected ions. The main objective of this experiment is to study the rate coefficients, and identification of reaction channels between cold K atoms and Ca+ ions. Subsequently this setup will be used to study reactions between cold K atoms and sympathetically cooled molecular ions such as CaO+, and to study internal state quenching of molecular ions.

  13. An investigation of the oxidative potential of potassium permanganate and chlorine dioxide during the oxidation of reduced manganese

    OpenAIRE

    Hair, David Hayne

    1987-01-01

    This project determined the thermodynamic potentials for various reactions between reduced manganese (Mn+2), manganese oxide (MnO2(s)), chlorine dioxide (C102), and potassium permanganate (KMnO4). Based on these findings, laboratory analyses were performed to determine if these reactions would occur under simulated water treatment plant conditions. In addition, a speciation procedure was developed to quantify the various species of manganese and chlorine dioxide present in a...

  14. Regulation of Arterial Tone by Activation of Calcium-Dependent Potassium Channels

    Science.gov (United States)

    Brayden, Joseph E.; Nelson, Mark T.

    1992-04-01

    Blood pressure and tissue perfusion are controlled in part by the level of intrinsic (myogenic) vascular tone. However, many of the molecular determinants of this response are unknown. Evidence is now presented that the degree of myogenic tone is regulated in part by the activation of large-conductance calcium-activated potassium channels in arterial smooth muscle. Tetraethylammonium ion (TEA^+) and charybdotoxin (CTX), at concentrations that block calcium-activated potassium channels in smooth muscle cells isolated from cerebral arteries, depolarized and constricted pressurized cerebral arteries with myogenic tone. Both TEA^+ and CTX had little effect on arteries when intracellular calcium was reduced by lowering intravascular pressure or by blocking calcium channels. Elevation of intravascular pressure through membrane depolarization and an increase in intracellular calcium may activate calcium-activated potassium channels. Thus, these channels may serve as a negative feedback pathway to control the degree of membrane depolarization and vasoconstriction.

  15. Growth, grain yield and calcium, potassium and magnesium accumulation in common bean plants as related to calcium nutrition

    Directory of Open Access Journals (Sweden)

    Lucas da Silva Domingues

    2016-04-01

    Full Text Available The objective of this work was to evaluate the plant growth and grain yield characteristics and the accumulation of calcium, potassium and magnesium in the leaves and grains of common bean cultivars grown with different calcium concentrations in the nutrient solution. Two experiments were conducted with nutrient solutions in a soilless system in a greenhouse. In the first experiment, five calcium concentrations (1.10, 1.65, 2.20, 2.75 and 3.30 mmol L-1 and three common bean cultivars (Iraí, BRS Expedito and Carioca were evaluated. Higher calcium concentrations (2.20, 2.75, 3.30, 3.85, 4.40 and 4.95 mmol L-1and two common bean cultivars (BRS Expedito and Carioca were tested in the second experiment. Dry mass of the shoot and root, grain yield and calcium accumulation in the leaves and grains increased linearly in common bean plants supplied with calcium concentrations between 2.20 and 4.95 mmol L-1. The high calcium concentration did not reduce the accumulation of calcium, potassium and magnesium in the leaves and grains. Common bean plants grown with high calcium concentrations present higher dry mass of the shoot and root, high grain yield and high calcium concentration in the leaves and grains.

  16. Whole-cell recordings of calcium and potassium currents in acutely isolated smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    Qing Cai; Zhong-Liang Zhu; Xiao-Li Fan

    2006-01-01

    AIM: To record calcium and potassium currents in acutely isolated smooth muscle cells of mesenteric arterial branches in rats.METHODS: Smooth muscle cells were freshly isolated by collagenase digest and mechanical trituration with polished pipettes. Patch clamp technique in whole-cell mode was employed to record calcium and potassium currents.RESULTS: The procedure dissociated smooth muscle cells without impairing the electrophysiological characteristics of the cells. The voltage-gated Ca2+ and potassium currents were successfully recorded using whole-cell patch clamp configuration.CONCLUSION: The method dissociates smooth muscle cells from rat mesenteric arterial branches. Voltage-gated channel currents can be recorded in this preparation.

  17. [Magnesium, calcium and potassium: "no one was born alone"].

    Science.gov (United States)

    Rapisarda, Francesco; Portale, Grazia; Ferrario, Silvia; Sessa, Concetto; Aliotta, Roberta; Zanoli, Luca; Fatuzzo, Pasquale

    2016-01-01

    In contrast to other ions, magnesium is treated as an orphan by the body: there are no hormones that have a substantial role in regulating urinary magnesium excretion, and bone, the principal reservoir of magnesium, does not readily exchange with circulating magnesium.The Mg ++ is often overlooked by physicians in the differential diagnosis because it is considered insignificant, but its role is crucial for cells function, first of all neurons and cardiomyocytes. A condition of hypocalcemia associated with hypokalemia, especially in the presence of chronic renal failure, should raise suspicion of a lack of Mg ++.We report the case of an old man of 77 year with kidney transplant for 13 years, treated with cyclosporine, and sodium mycophenolate and steroid who, for about a month, accused impaired balance and walking instability, who fell accidentally down with wrist fracture.Blood tests showed hypocalcemia and hypokalemia, and so we required dosage of serum and urinary magnesium. A significant reduction in the ion plasma concentration was seen, associated to a fraction of excretion inappropriately high in relation to the degree of hypomagnesemia.The cause of this important renal loss is likely attributable to cyclosporine, a drug that has as a side effect the inhibition of the reabsorption of Mg ++ in the distal convoluted tubule. then, oral supplementation was started (244 mg of Mg ++ ion / day), with subsequent normalization, after a few days, not only of magnesiemia, but also in serum calcium and potassium levels, and improvement of neurological symptoms.Hypomagnesaemia is common in patients with renal transplantation in therapy with calcineurin inhibitors ICN, due to the effects of such drugs on the TRPM6 transporter present in the kidney distal convoluted tubule. To prevent complications caused by chronic and severe depletion of magnesium in this particular population, we recommend periodic monitoring of magnesium plasma levels. PMID:26913745

  18. Extraction of lithium from β-spodumene using chlorination roasting with calcium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Lucía I., E-mail: lbarbosa@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 17, CP 5700 San Luis (Argentina); González, Jorge A. [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 17, CP 5700 San Luis (Argentina); Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Jorge Contreras 1300, Parque General San Martín, CP M5502JMA Mendoza (Argentina); Ruiz, María del Carmen [Instituto de Investigaciones en Tecnología Química (INTEQUI-CONICET), Facultad de Química Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 17, CP 5700 San Luis (Argentina)

    2015-04-10

    Highlights: • β-Spodumene was roasted with calcium chloride to extract lithium. • The optimal conditions of the chlorination process are 900 °C and 120 min. • The products of the reaction are lithium chloride, anorthite, and silica. - Abstract: Chlorination roasting was used to extract lithium as lithium chloride from β-spodumene. The roasting was carried out in a fixed bed reactor using calcium chloride as chlorinating agent. The mineral was mixed with CaCl{sub 2} on a molar ratio of 1:2. Reaction temperature and time were investigated. The reactants and roasted materials were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD) and atomic absorption spectrophotometry (AAS). The mineral starts to react with CaCl{sub 2} at around 700 °C. The optimal conditions of lithium extraction were found to be 900 °C and 120 min of chlorination roasting, under which it is attained a conversion degree of 90.2%. The characterization results indicate that the major phases present in the chlorinating roasting residue are CaAl{sub 2}Si{sub 2}O{sub 8}, SiO{sub 2}, and CaSiO{sub 3}.

  19. Extraction of lithium from β-spodumene using chlorination roasting with calcium chloride

    International Nuclear Information System (INIS)

    Highlights: • β-Spodumene was roasted with calcium chloride to extract lithium. • The optimal conditions of the chlorination process are 900 °C and 120 min. • The products of the reaction are lithium chloride, anorthite, and silica. - Abstract: Chlorination roasting was used to extract lithium as lithium chloride from β-spodumene. The roasting was carried out in a fixed bed reactor using calcium chloride as chlorinating agent. The mineral was mixed with CaCl2 on a molar ratio of 1:2. Reaction temperature and time were investigated. The reactants and roasted materials were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD) and atomic absorption spectrophotometry (AAS). The mineral starts to react with CaCl2 at around 700 °C. The optimal conditions of lithium extraction were found to be 900 °C and 120 min of chlorination roasting, under which it is attained a conversion degree of 90.2%. The characterization results indicate that the major phases present in the chlorinating roasting residue are CaAl2Si2O8, SiO2, and CaSiO3

  20. Direct determination of calcium, sodium and potassium in fermented milk products

    Directory of Open Access Journals (Sweden)

    Kravić Snežana Ž.

    2012-01-01

    Full Text Available The aim of this study was the investigation of the possibilities of direct determination of calcium, sodium and potassium in the commercial and kombucha-based fermented milk products by flame photometry. Two procedures were used for sample preparation: simple dilution with water (direct method and extraction with mineral acid. Calcium, sodium and potassium levels determined after mentioned sample preparation methods were compared. The results showed that the differences between the values obtained for the different sample treatment were within the experimental error at the 95% confidence level. Compared to the method based on extraction with mineral acid, the direct method is efficient, faster, simpler, cheaper, and operates according to the principles of Green Chemistry. Consequently, the proposed method for the direct determination of calcium, sodium and potassium could be applied for the rapid routine analysis of the mineral content in the fermented dairy products. [Projekat Ministarstva nauke Republike Srbije, br. III 46009

  1. Corrosion behavior of silicon nitride, magnesium oxide, and several metals in molten calcium chloride with chlorine

    International Nuclear Information System (INIS)

    In this paper corrosion studies are described in a molten calcium chloride environment sparged with chlorine gas at 850 degrees C, both in the melt and in the gas phase above the salt, in support of efforts at Westinghouse Savannah River Company to develop more resistant materials of construction for molten salt processing of plutonium. Corrosion rates and electron microscope analyses are reported for Inconel alloys 601 and 617, tantalum, tungsten, magnesium oxide, and silicon nitride. Silicon nitride exhibited the greatest resistance, showing 2 · h loss in both melt and vapor None of the metallic coupons withstood the chlorine vapor environment, although Inconel indicated resistance immersed in the melt if protected from chlorine gas

  2. Effect of exhausting exercise and calcium supplementation on potassium, magnesium, copper, zinc and calcium levels in athletes

    International Nuclear Information System (INIS)

    Present study was performed to determine four week calcium supplementation and athleticism exercise on plasma potassium, calcium, magnesium, cupper and zinc levels in resting and exhaustion. Research was carried out on 30 healthy male people. Group 1; Exercise, Group 2; Exercise + Calcium supplementation, Group 3; Sedentary + Calcium supplemented. All elements levels increased by exhausting exercise (P<0.05). Plasma K and Ca levels increased in exercise group after supplementation (P<0.05). Ca levels increased in exercise + supplemented group (P<0.05). This increase was much more in group three (P<0.05). Plasma Cu levels increased by Ca supplementation in sedentary (P<0.05). Exhausting exercise increased Zn levels in sedentary after supplementation (P<0.05). The results of present study show that calcium supplementation for 4 week does not have clear affect on potassium and Mg. However, calcium levels were increased by supplementation and Cu after the supplementation. It was also exhausting exercise that caused increase in all parameters. (author)

  3. Determination of experimental K-shell fluorescence yield for potassium and calcium compounds

    Indian Academy of Sciences (India)

    E Tiraşoğlu; Ö Söğüt

    2008-03-01

    K-shell fluorescence yields were experimentally determined for potassium and calcium compounds using a Si(Li) X-ray detector system (FWHM=5.96 keV at 160 eV). The samples were excited by 5.96 keV photons produced by a 55Fe radioisotope source. The experimental values are systematically lower than the theoretical values.

  4. [Sodium, potassium and calcium content in regional dishes consumed in Sonora, Mexico].

    Science.gov (United States)

    Grijalva Haro, M I; Valencia, M E; Wyatt, J

    1990-06-01

    The content of sodium, potassium and calcium was determined in 15 regional dishes, by atomic absorption spectrophotometry. The Na:K ratio was high in most of the dishes due to the high sodium content and low content of potassium found. The higher sources of the studied minerals were "tortilla de harina" with 1,372.8 mg/100 g of sodium; "chorizo con papas" with 466 mg/100 g of potassium, and "calabacitas con queso" with 244.1 mg/100 g of calcium. Two of the dishes considered as desserts, "capirotada" and "arroz con leche" showed the lowest Na:K ratio (0.66 and 0.81, respectively). PMID:2133188

  5. Potassium

    Science.gov (United States)

    ... stimulation and in the contraction of muscles. Cellular enzymes need potassium to work properly. A potassium deficiency ... or prune juice, honeydew melons, prunes, molasses and potatoes. Some foods high in potassium are also high ...

  6. Chlorine

    Science.gov (United States)

    ... chlorine gas are inhaled. Fluid in the lungs (pulmonary edema) that may be delayed for a few hours ... health problems such as fluid in the lungs (pulmonary edema) following the initial exposure. How people can protect ...

  7. Effect of different concentrations of potassium silicate, nano-silicon and calcium chloride on concentration of potassium, calcium and magnesium, chlorophyll content and number of florets of Asiatic lily cv. ‘Brunello’

    OpenAIRE

    N. Mirabbasi; A. Nikbakht; N. Etemadi; M.R. Sabzalian

    2013-01-01

    Production of many cut flowers, such as lilium, is very common in Iran. Flower quality has special importance in lilium flower production process, and proper nutrition is one of the major effective factors. This research was conducted to investigate the effect of different concentrations of potassium silicate, nano-silicon and calcium chloride on concentration of potassium, calcium and magnesium, chlorophyll index and number of florets of Asiatic lily 'Brunello'. The experiment was carried ou...

  8. Calcium-Activated Potassium Channels at Nodes of Ranvier Secure Axonal Spike Propagation

    Directory of Open Access Journals (Sweden)

    Jan Gründemann

    2015-09-01

    Full Text Available Functional connectivity between brain regions relies on long-range signaling by myelinated axons. This is secured by saltatory action potential propagation that depends fundamentally on sodium channel availability at nodes of Ranvier. Although various potassium channel types have been anatomically localized to myelinated axons in the brain, direct evidence for their functional recruitment in maintaining node excitability is scarce. Cerebellar Purkinje cells provide continuous input to their targets in the cerebellar nuclei, reliably transmitting axonal spikes over a wide range of rates, requiring a constantly available pool of nodal sodium channels. We show that the recruitment of calcium-activated potassium channels (IK, KCa3.1 by local, activity-dependent calcium (Ca2+ influx at nodes of Ranvier via a T-type voltage-gated Ca2+ current provides a powerful mechanism that likely opposes depolarizing block at the nodes and is thus pivotal to securing continuous axonal spike propagation in spontaneously firing Purkinje cells.

  9. Calcium-Activated Potassium (BK) Channels Are Encoded by Duplicate slo1 Genes in Teleost Fishes

    OpenAIRE

    Rohmann, Kevin N.; Deitcher, David L.; Bass, Andrew H.

    2009-01-01

    Calcium-activated, large conductance potassium (BK) channels in tetrapods are encoded by a single slo1 gene, which undergoes extensive alternative splicing. Alternative splicing generates a high level of functional diversity in BK channels that contributes to the wide range of frequencies electrically tuned by the inner ear hair cells of many tetrapods. To date, the role of BK channels in hearing among teleost fishes has not been investigated at the molecular level, although teleosts account ...

  10. Identification of Premature Ventricular Contraction (PVC) Caused by Disturbances in Calcium and Potassium Ion Concentrations Using Artificial Neural Networks

    OpenAIRE

    Júlio César Dillinger Conway; Caroline Araújo Raposo; Sergio Diaz Contreras; Jadson Cláudio Belchior

    2014-01-01

    Abnormalities in the concentrations of metallic ions such as calcium and potassium can, in principle, lead to cardiac arrhythmias. Unbalance of these ions can alter the electrocardiogram (ECG) signal. Changes in the morphology of the ECG signal can occur due to changes in potassium concentration, and shortening or extension of this signal can occur due to calcium excess or deficiency, respectively. The diagnosis of these disorders can be complicated, making the modeling of such a system compl...

  11. Application of in situ chemical oxidation technique with potassium permanganate for the remediation of a shallow aquifer contaminated with chlorinated solvents

    OpenAIRE

    Alaine Santos da Cunha; Reginaldo Antonio Bertolo

    2012-01-01

    In situ chemical oxidation is a method that is frequently being used for the remediation of contaminated areas, since it presents an adequate efficiency in the reduction of the contaminant mass, particularly chlorinated ethenes, in a relatively short period of time. This manuscript presents the results of the application of this method, using the injection of potassium permanganate as the remediation agent, in an impacted area with chlorinated organic compounds, especially 1,1-dichloroethene....

  12. Synthesis of porous poly(acrylamide hydrogels using calcium carbonate and its application for slow release of potassium nitrate

    Directory of Open Access Journals (Sweden)

    2009-05-01

    Full Text Available Porous poly(acrylamide was synthesized using calcium carbonate microparticles and subsequent acid treatment to remove the calcium carbonate. Methylenebisacrylamide and ammonium persulfate/sodium metabisulfite were used as crosslinking agent and redox initiator, respectively. The porous structure of resulted hydrogels was confirmed using SEM micrographs. The effect of methylenebisacrylamide concentration and calcium carbonate amount on the swelling of the hydrogels was investigated. The results showed that the effect of methylenebisacrylamide and calcium carbonate variables on the swelling is reverse. The hydrogels were subsequently utilized for the loading of potassium nitrate. Potassium nitrate as active agent was loaded into hydrogels and subsequently the release of this active agent was investigated. In these series of investigation, the effect of content of loading, methylenebisacrylamide and calcium carbonate amount on the release of potassium nitrate from hydrogels was investigated.

  13. Potassium

    Science.gov (United States)

    Potassium is a mineral that the body needs to work normally. It helps nerves and muscles communicate. ... products out of cells. A diet rich in potassium helps to offset some of sodium's harmful effects ...

  14. Production of Potassium and Calcium Hydroxide, Compost and Humic Acid from Sago (Metroxylon sagu Waste

    Directory of Open Access Journals (Sweden)

    C. P. Auldry

    2009-01-01

    Full Text Available Problem statement: Agriculture waste such as Sago Waste (SW has a potential to cause pollution when the waste is discarded into rivers. In order to add value to SW, a study was conducted to produce potassium and calcium hydroxide, compost and Humic Acid (HA from SW. Approach: The SW was air-dried and some grinded. The grinded SW was incinerated at 600°C. Potassium and calcium hydroxide was extracted by dissolving the ash in distilled water at a ratio of 1:500 (ash: water, equilibrated for 24 h at 150 rpm using a mechanical shaker and filtered. The ungrinded SW was used for compost production. The compost was produced by mixing SW (80% + chicken feed (10% + chicken dung slurry (5% + molasses (5%. Results: The hydroxide extracted from ash of SW was used to isolate HA of composted SW. The molarity and pH of the hydroxide were 0.002M and 10 respectively. Calcium (42.88 mg kg-1 and potassium (29.51 mg kg-1 content were high in the hydroxide compared with other elements. The compost took about 60 days to mature. There was an increased in pH, ash, Cation Exchange Capacity (CEC and HA and a decreased in temperature, C/N ratio, C/P ratio and organic matter. The hydroxide was able to extract 1% of HA from the composted SW. A comparison between the yields of HA extracted from the composted SW using the hydroxide of the SW and that of the analytical grade showed no statistically difference. The chemical characteristics of HA from the composted SW were in standard range. Conclusion: Potassium and calcium hydroxide, compost and HA can be produced from sago waste. Low morality of the hydroxide is able to produce good quality of HA from composted sago waste. The HA can be reconstituted with K and Ca from potassium and calcium hydroxide to produce K-Ca-humate and this needs to be investigated as a form of organic based fertilizer.

  15. SIMULATING THE IN-SITU OXIDATIVE TREATMENT OF CHLORINATED ETHYLENES BY POTASSIUM PERMANGANATE

    Science.gov (United States)

    In recent years, MnO{sub}4 oxidation of chlorinated ethylenes (PCE, TCE, and DCE) has emerged as a potentially useful approach for destroying these componds in water. Recently, more applied studies have looked at whether KMnO{sub}4 could be used in remediating sites contaminated ...

  16. Immunolocalization and expression of small-conductance calcium-activated potassium channels in human myometrium

    DEFF Research Database (Denmark)

    Rosenbaum, Sofia T; Svalø, Julie; Nielsen, Karsten;

    2012-01-01

    Small-conductance calcium-activated potassium (SK3) channels have been detected in human myometrium and we have previously shown a functional role of SK channels in human myometrium in vitro. The aims of this study were to identify the precise localization of SK3 channels and to quantify SK3 m...... muscle cells, and that the molecular expression of SK3 channels is higher in non-pregnant compared to pregnant myometrium. On the basis of our previous study and the present findings, we propose that SK3 activators reduce contractility in human myometrium by modulating telocyte function. This is the...

  17. Potassium silicate and calcium silicate on the resistance of soybean to Phakopsora pachyrhizi infection

    OpenAIRE

    Maria Fernanda Cruz; Fabrício Ávila Rodrigues; Ana Paula Cardoso Diniz; Maurilio Alves Moreira; Everaldo Gonçalves de Barros

    2013-01-01

    The control of Asian Soybean Rust (ASR), caused by Phakopsora pachyrhizi, has been difficult due to the aggressiveness of the pathogen and the lack of resistant cultivars. The objective of this study was to evaluate the effects of spray of potassium silicate (PS) and soil amendment with calcium silicate (CS) on soybean resistance to ASR. The PS solution was sprayed to leaves 24 hours prior to fungal inoculation while CS was amended to the soil at thirty-five days before sowing. The infection ...

  18. Calcium-Activated Potassium Channels in Ischemia Reperfusion: A Brief Update

    Directory of Open Access Journals (Sweden)

    Jean-Yves eTano

    2014-10-01

    Full Text Available Ischemia and reperfusion (IR injury constitutes one of the major causes of cardiovascular morbidity and mortality. The discovery of new therapies to block/mediate the effects of IR is therefore an important goal in the biomedical sciences. Dysfunction associated with IR involves modification of calcium-activated potassium channels (KCa through different mechanisms, which are still under study. Respectively, the KCa family, major contributors to plasma membrane calcium influx in cells and essential players in the regulation of the vascular tone are interesting candidates. This family is divided into two groups including the large conductance (BKCa and the small/intermediate conductance (SKCa/IKCa K+ channels. In the heart and brain, these channels have been described to offer protection against IR injury. BKCa and SKCa channels deserve special attention since new data demonstrate that these channels are also expressed in mitochondria. More studies are however needed to fully determine their potential use as therapeutic targets.

  19. Potassium

    Science.gov (United States)

    ... Take all forms of potassium with a full glass of water or fruit juice.Add the liquid ... to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in ...

  20. Production of Potassium and Calcium Hydroxide, Compost and Humic Acid from Sago (Metroxylon sagu) Waste

    OpenAIRE

    C. P. Auldry; Ahmed, O. H.; A. M.N. Muhamad; H.M. Nasir; M. Jiwan

    2009-01-01

    Problem statement: Agriculture waste such as Sago Waste (SW) has a potential to cause pollution when the waste is discarded into rivers. In order to add value to SW, a study was conducted to produce potassium and calcium hydroxide, compost and Humic Acid (HA) from SW. Approach: The SW was air-dried and some grinded. The grinded SW was incinerated at 600°C. Potassium and calcium hydroxide was extracted by dissolving the ash in distilled water at a ratio of 1:500 (ash: water), equilibrated for ...

  1. Analysis of the effects of calcium or magnesium on voltage-clamp currents in perfused squid axons bathed in solutions of high potassium.

    Science.gov (United States)

    Rojas, E; Taylor, R E; Atwater, I; Bezanilla, F

    1969-10-01

    Isolated axons from the squid, Dosidicus gigas, were internally perfused with potassium fluoride solutions. Membrane currents were measured following step changes of membrane potential in a voltage-clamp arrangement with external isosmotic solution changes in the order: potassium-free artificial seawater; potassium chloride; potassium chloride containing 10, 25, 40 or 50, mM calcium or magnesium; and potassium-free artificial seawater. The following results suggest that the currents measured under voltage clamp with potassium outside and inside can be separated into two components and that one of them, the predominant one, is carried through the potassium system. (a) Outward currents in isosmotic potassium were strongly and reversibly reduced by tetraethylammonium chloride. (b) Without calcium or magnesium a progressive increase in the nontime-dependent component of the currents (leakage) occurred. (c) The restoration of calcium or magnesium within 15-30 min decreases this leakage. (d) With 50 mM divalent ions the steady-state current-voltage curve was nonlinear with negative resistance as observed in intact axons in isosmotic potassium. (e) The time-dependent components of the membrane currents were not clearly affected by calcium or magnesium. These results show a strong dependence of the leakage currents on external calcium or magnesium concentration but provide no support for the involvement of calcium or magnesium in the kinetics of the potassium system. PMID:5823216

  2. Influence of pre-harvest calcium, potassium and triazole application on the proteome of apple at harvest

    NARCIS (Netherlands)

    Buts, Kim; Hertog, M.L.A.T.M.; Ho, Quang Tri; America, A.H.P.; Cordewener, J.H.G.; Vercammen, J.; Carpentier, S.C.; Nicolaï, Bart

    2016-01-01

    Braeburn browning disorder is a storage disease characterised by flesh browning and lens-shaped cavities. The incidence of this postharvest diorder is known to be affected by pre-harvest application of fertilisers and triazole-based fungicides. Recent work has shown that calcium and potassium reduce

  3. Study of granitic biotites by X-ray fluorescence analysis: determination of iron, manganese, titanium, calcium, potassium, silicon and aluminium

    International Nuclear Information System (INIS)

    A method for the quantitative determination of iron, manganese, titanium, calcium potassium, silicon, and aluminium, is reported, Sample preparation is carried out by the miniature flux technique, and rubidium is used as internal standard for silicon and aluminium. (Author) 5 refs

  4. The influence of potassium and calcium ions on nitrogen metabolism of cucumber seedlings

    Directory of Open Access Journals (Sweden)

    Genowefa Kubik-Dobosz

    2014-02-01

    Full Text Available It was found that K+ or Ca2+ deficiency in a nitrate or ammonium medium increased the amount of accumulated total and non-protein nitrogen in some organs of cucumber seedlings, as also caused changes in accumulated potassium and calcium. Lack of K+ or Ca2+ in a medium which did not contain nitrogen led to an increased level of glutamate dehydrogenase, alanine aminotransferase and aspartate aminotransferase activity in the cotyledons and roots of cucumbers. Similar changes in the activity of these enzymes were noted in certain organs of seedlings growing in nitrate or ammonium medium with decreased K+ or Ca2+ contents, although the magnitude of these changes depended upon the applied dosage of these cations, the form of mineral nitrogen, developmental phase of plants and the plant organ dealt with.

  5. Synthesis of potassium and calcium uranium vanadates, analogues of Carnotite and meta tyuyamunite minerals

    International Nuclear Information System (INIS)

    The aim of this study was to develop a synthesis of meta tyuyamunite (Ca(VUO6)2·3-5H2O) and carnotite (KVUO6·1-3H2O) under hydrothermal conditions. Also, crystals obtained from this synthesis were compared with crystals from melting method. The analyses of synthesis products were performed by X-ray techniques. X-ray diffraction was used for both species identification, whereas scanning electron microscopy was used to analyze their morphology and elemental composition. Both uranium vanadates were positive synthesized under hydrothermal conditions, besides, their morphology presents particles agglomerates. Calcium uranium vanadate agglomerates contain well-defined crystals, whereas potassium uranium vanadate agglomerates consist in fine powder particles. (Author)

  6. Synthesis of potassium and calcium uranium vanadates, analogues of Carnotite and meta tyuyamunite minerals

    Energy Technology Data Exchange (ETDEWEB)

    Requena Y, J. L.; Reyes C, M.; Torres M, E.; Lardizabal, D.; Montero C, M. E. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes No. 120, Complejo Industrial Chihuahua, 31109 Chihuahua (Mexico); Riveros, H., E-mail: elena.montero@cimav.edu.mx [UNAM, Instituto de Fisica, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2012-06-15

    The aim of this study was to develop a synthesis of meta tyuyamunite (Ca(VUO{sub 6}){sub 2}{center_dot}3-5H{sub 2}O) and carnotite (KVUO{sub 6}{center_dot}1-3H{sub 2}O) under hydrothermal conditions. Also, crystals obtained from this synthesis were compared with crystals from melting method. The analyses of synthesis products were performed by X-ray techniques. X-ray diffraction was used for both species identification, whereas scanning electron microscopy was used to analyze their morphology and elemental composition. Both uranium vanadates were positive synthesized under hydrothermal conditions, besides, their morphology presents particles agglomerates. Calcium uranium vanadate agglomerates contain well-defined crystals, whereas potassium uranium vanadate agglomerates consist in fine powder particles. (Author)

  7. On the content of sodium, potassium, magnesium, calcium and chlorine in organs of Wistar rats

    International Nuclear Information System (INIS)

    The content of the Na, K, Mg, Ca and Cl in heart, kidney, liver, small and large intestine was investigated by means of instrumental neutron activation analysis of normal (intact) and thymectomized Wistar rats at different age up to 12 months and different postoperative periods. The instrumental neutron activation analysis was applied, using neutron flux with m=5.1012n/cm2.sec, Ge/Li detector (resolution 2,3 Kev at 1332 Kev of Co60) with decay time 120 sec (for Mg, Cl, Ca) and 2h (for Na, K). The analytical procedure was conventionalyzed reasononably to ensure the reproducibility and minimize the possibility of random errors

  8. Three-dimensional density-dependent flow and multicomponent reactive transport modeling of chlorinated solvent oxidation by potassium permanganate

    Science.gov (United States)

    Henderson, Thomas H.; Mayer, K. Ulrich; Parker, Beth L.; Al, Tom A.

    2009-05-01

    A popular method for the treatment of aquifers contaminated with chlorinated solvents is chemical oxidation based on the injection of potassium permanganate (KMnO 4). Both the high density (1025 gL - 1 ) and reactivity of the treatment solution influence the fate of permanganate (MnO 4) in the subsurface and affect the degree of contaminant treatment. The MIN3P multicomponent reactive transport code was enhanced to simulate permanganate-based remediation, to evaluate the pathways of MnO 4 utilization, and to assess the role of density contrasts for the delivery of the treatment solution. The modified code (MIN3P-D) provides a direct coupling between density-dependent fluid flow, solute transport, contaminant treatment, and geochemical reactions. The model is used to simulate a field trial of TCE oxidation in a sandy aquifer that is underlain by an aquitard. Three-dimensional simulations are conducted for a coupled reactive system comprised of ten aqueous components, two mineral phases, TCE (dissolved, adsorbed, and NAPL), reactive organic matter, and including ion exchange reactions. Model parameters are constrained by literature data and a detailed data set from the field site under investigation. The general spatial and transient evolution in observed concentrations of the oxidant, dissolved TCE, and reaction products are adequately reproduced by the simulations. The model elucidates the important role of density-induced flow and transport on the distribution of the treatment solution into NAPL containing regions located at the aquifer-aquitard interface. Model results further suggest that reactions that do not directly affect the stability of MnO 4 have a negligible effect on solution density and MnO 4 delivery.

  9. Calcium-activated potassium channels in insect pacemaker neurons as unexpected target site for the novel fumigant dimethyl disulfide.

    Science.gov (United States)

    Gautier, Hélène; Auger, Jacques; Legros, Christian; Lapied, Bruno

    2008-01-01

    Dimethyl disulfide (DMDS), a plant-derived insecticide, is a promising fumigant as a substitute for methyl bromide. To further understand the mode of action of DMDS, we examined its effect on cockroach octopaminergic neurosecretory cells, called dorsal unpaired median (DUM) neurons, using whole-cell patch-clamp technique, calcium imaging and antisense oligonucleotide strategy. At low concentration (1 microM), DMDS modified spontaneous regular spike discharge into clear bursting activity associated with a decrease of the amplitude of the afterhyperpolarization. This effect led us to suspect alterations of calcium-activated potassium currents (IKCa) and [Ca(2+)](i) changes. We showed that DMDS reduced amplitudes of both peak transient and sustained components of the total potassium current. IKCa was confirmed as a target of DMDS by using iberiotoxin, cadmium chloride, and pSlo antisense oligonucleotide. In addition, we showed that DMDS induced [Ca(2+)](i) rise in Fura-2-loaded DUM neurons. Using calcium-free solution, and (R,S)-(3,4-dihydro-6,7-dimethoxy-isoquinoline-1-yl)-2-phenyl-N,N-di-[2-(2,3,4-trimethoxy-phenyl)ethyl]-acetamide (LOE 908) [an inhibitor of transient receptor potential (TRP)gamma], we demonstrated that TRPgamma initiated calcium influx. By contrast, omega-conotoxin GVIA (an inhibitor of N-type high-voltage-activated calcium channels), did not affect the DMDS-induced [Ca(2+)](i) rise. Finally, the participation of the calcium-induced calcium release mechanism was investigated using thapsigargin, caffeine, and ryanodine. Our study revealed that DMDS-induced elevation in [Ca(2+)](i) modulated IKCa in an unexpected bell-shaped manner via intracellular calcium. In conclusion, DMDS affects multiple targets, which could be an effective way to improve pest control efficacy of fumigation. PMID:17942746

  10. Determination of calcium, copper, chromium, iron, magnesium, manganese, potassium, sodium and zinc in ethanol by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    The direct determinacao of calcium, copper, chomium, iron, magnesium, manganese, potassium, sodium and zinc in ethanol by atomic absorption spectrometry with, air-acetylene flame is proposed. Effects of fuel/oxidant ratio, burner height and water content in the samples were investigated in detail. The method allows the determition of the elements with good precision (r.s.d. -1 for the elements tested. (author)

  11. Ryanodine modification of cardiac muscle responses to potassium-free solutions. Evidence for inhibition of sarcoplasmic reticulum calcium release

    OpenAIRE

    1983-01-01

    To test whether ryanodine blocks the release of calcium from the sarcoplasmic reticulum in cardiac muscle, we examined its effects on the aftercontractions and transient depolarizations or transient inward currents developed by guinea pig papillary muscles and voltage-clamped calf cardiac Purkinje fibers in potassium-free solutions. Ryanodine (0.1-1.0 microM) abolished or prevented aftercontractions and transient depolarizations by the papillary muscles without affecting any of the other sequ...

  12. Calcium-activated potassium channels mediated blood-brain tumor barrier opening in a rat metastatic brain tumor model

    OpenAIRE

    2007-01-01

    Background The blood-brain tumor barrier (BTB) impedes the delivery of therapeutic agents to brain tumors. While adequate delivery of drugs occurs in systemic tumors, the BTB limits delivery of anti-tumor agents into brain metastases. Results In this study, we examined the function and regulation of calcium-activated potassium (KCa) channels in a rat metastatic brain tumor model. We showed that intravenous infusion of NS1619, a KCa channel agonist, and bradykinin selectively enhanced BTB perm...

  13. Determination of sodium, potassium, calcium, magnesium, iron, copper, zinc and mercury in contaminated wheat and wheat flour

    International Nuclear Information System (INIS)

    The wheat and wheat flour samples from district Khairpur, were dissolved in acids and analyzed spectrophotometrically for mercury contents, using dithiozone method. Mercury was found in 0.92-5.8 mg/ kg range, above the safe limits for human consumption, samples were also analysed for sodium, potassium, calcium, magnesium, iron, copper and zinc, after dry ashing, followed by acid dissolution and flame atomic absorption determination. Metal ions were found within the normal limits reported for wheat and wheat flour. (author)

  14. Potassium silicate and calcium silicate on the resistance of soybean to Phakopsora pachyrhizi infection

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Cruz

    2013-01-01

    Full Text Available The control of Asian Soybean Rust (ASR, caused by Phakopsora pachyrhizi, has been difficult due to the aggressiveness of the pathogen and the lack of resistant cultivars. The objective of this study was to evaluate the effects of spray of potassium silicate (PS and soil amendment with calcium silicate (CS on soybean resistance to ASR. The PS solution was sprayed to leaves 24 hours prior to fungal inoculation while CS was amended to the soil at thirty-five days before sowing. The infection process of P. pachyrhizi was investigated by scanning electron microscopy. The uredia on leaves of plants sprayed with PS were smaller and more compact than those observed on the leaves of plants grown in soil amended with CS or in soil non-amended with CS (control treatment. On leaves of plants from the control treatment, uredia produced many urediniospores at 9 days after inoculation, and the ASR severity was 15, 8 and 9%, respectively, for plants from control, PS and CS treatments. In conclusion, the spray of PS contributed to reduce the number of uredia per cm² of leaf area and both PS spray and CS resulted in lower ASR symptoms.

  15. Potassium conductances mediate bidirectional state-dependent modulation of action potential evoked dendritic calcium signals in dentate gyrus granule cells

    Directory of Open Access Journals (Sweden)

    János Brunner

    2014-03-01

    Full Text Available Backpropagating action potentials (bAPs and local calcium signals that they trigger are fundamental for dendritic functions. Here we addressed the question what extent the changes of local dendritic membrane properties can contribute to the shaping of the coupling between dendritic action potentials and the local calcium responses. Using a combination of in vitro electrophysiological and confocal imaging techniques we found that activation of dendritic GIRK channels via mGlu2 or GABAB receptors enhanced the bAP¬-triggered calcium signals in the dendrites of dentate gyrus granule cells (GCs. The enhancement of calcium signals was significant only in those dendritic regions, where these receptors are predominantly expressed. Similarly to GIRK channel activation, somatic hyperpolarization by DC current injection (from -64 mV to -77 mV, significantly increased bAP-associated calcium signals in the proximal dendrites. The hyperpolarization was associated with a decrease in the input resistance due to the rectification of the membrane potential of GCs. The effect of hyperpolarization on the calcium signals was maintained when T-type calcium currents were blocked but it decreased when GIRK channels were inhibited. Simultaneous dual somato-dendritic recordings from GCs showed that somatic hyperpolarization accelerated the repolarization phase of dendritic bAP in the proximal region whereas the rising phase and peak amplitude was not affected. We hypothesize that the larger driving force for calcium ions during the faster repolarization can contribute to the increasing in calcium signals. Employment of previously recorded dendritic bAP waveforms from hyperpolarized membrane potential as voltage command evoked larger calcium currents in nucleated patches compared to bAP waveform from the same recording at depolarized membrane potential. Furthermore, addition of native, high-voltage activated, inactivating potassium conductance by somatic dynamic clamp

  16. Stability and resistance of nickel catalysts for hydrodeoxygenation:carbon deposition and effects of sulfur, potassium, and chlorine in the feed

    OpenAIRE

    Mortensen, Peter Mølgaard; Gardini, Diego; Hudson W. P. Carvalho; Damsgaard, Christian Danvad; Grunwaldt, Jan-Dierk; Jensen, Peter Arendt; Wagner, Jakob Birkedal; Jensen, Anker Degn

    2014-01-01

    The long term stability and resistance toward carbon deposition, sulfur, chlorine, and potassium of Ni/ZrO2 as a catalyst for the hydrodeoxygenation (HDO) of guaiacol in 1-octanol (as a model compound system for bio-oil) has been investigated at 250 degrees C and 100 bar in a trickle bed reactor setup. Without impurities in the feed good stability of the Ni/ZrO2 catalyst could be achieved over more than 100 h of operation, particularly for a sample prepared with small Ni particles, which mini...

  17. A flow-system comparison of the reactivities of calcium superoxide and potassium superoxide with carbon dioxide and water vapor

    Science.gov (United States)

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

    1982-01-01

    A single pass flow system was used to test the reactivity of calcium superoxide with respiratory gases and the performance was compared to that of potassium superoxide. The KO2 system is used by coal miners as a self-contained unit in rescue operations. Particular attention was given to the reactivity with carbon dioxide and water vapor at different temperatures and partial pressures of oxygen, carbon dioxide, and water vapor. The calcium superoxide beds were found to absorb CO2 and H2O vapor, releasing O2. The KO2 bed, however, released O2 at twice the rate of CO2 absorption at 37 C. It is concluded that the calcium superoxide material is not a suitable replacement for the KO2 bed, although Ca(O2)2 may be added to the KO2 bed to enhance the CO2 absorption.

  18. Influence of Soil Reaction on Phosphorus, Potassium, Calcium and Magnesium Dynamics in Grapevine (Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Lepomir Čoga

    2009-03-01

    Full Text Available Influence of soil reaction on phosphorus, potassium, calcium and magnesium dynamics in grapevine was studied on the variety Sauvignon Blanc in 2007, in the Plešivica wine-growing region. Investigations were conducted on three vitisol subtypes: dystric cambisol (pHKCl 3.73-3.76, pseudogley (pHKCl 4.67-4.69 and rendzina on marl (pHKCl 7.21-7.27. To establish the amount and dynamics of P, K, Ca and Mg in plant material, leaf samples were taken three times during the growing period: at the flowering and veraison stages and at the end of the growing period. At all sampling times, significantly higher leaf contents of P, Ca and Mg were found on alkaline soil compared to acid soils, while differences in K levels were not statistically significant. Differences in P contents may be explained by better solubility and thereby better availability of P from Ca-phosphates compared to Al, Mn and Fe-phosphates in acid soils. In addition, the cation ratio K/(Ca+Mg that has a significant influence on grape quality, was also determined in leaves. Compared to optimal values (0.30–0.40, the least favourable ratio K/ (Ca+Mg was recorded at flowering on acid soils (0.38–0.77 and at harvest on calcareous soil (0.12–0.27. Differences in the content of sugar and total acids in must indicate a positive correlation between leaf contents of P, Ca and Mg and sugar content of must, and a negative correlation between leaf contents of P, Ca and Mg and the total acid content of must.

  19. Types of voltage—dependent calcium channels involved in high potassium depolarization—induced amylase secretion in the exocrine pancreatic tumour cell line AR4—2J

    Institute of Scientific and Technical Information of China (English)

    CUIZONGJIE

    1998-01-01

    In the perifused fura-2 loaded exocrine pancreatic acinar cell line AR4-2J pulses of high potassium induced repetitive increases in intracellular calcium,Attached cells when stimulated with high potassium secreted large amount of amylase.High potassium-induced secretion was dependent both on the concentration of potassium and duration of stimulation.High potassium induced increases in intracellular calcium were inhibited by voltage-dependent calcium channel anatagonists with an order of potency as follows:nifedipine>ω-agatoxin IVA>ω-conotoxin GVIA.In contrast,the L-type calcium channel anatagonist nifedipine almost completely inhibited potassium-induced amylase secretion,whereas the N-type channel antagonist ω-conotoxin GVIA was without effect.The P-type channel antagonist ω-agatoxin IVA had a small inhibitory effect,but this inhibition was not significant at the level of amylase secretion.In conclusion,the AR4-2J cell line posesses different voltage-dependent calcium channels(L,P,N)with the L-type predominantly involved in depolarization induced amylase secretion.

  20. In vivo studies on the nitrogen, chlorine, calcium and phosphorus composition of rats by neutron activation analysis

    International Nuclear Information System (INIS)

    The role of neutron activation analysis 'in vivo' to determine the elementary composition of the rat organism is demonstrated. In part one the possibilities offered by certain methods which establish the elementary composition of living organisms are analyzed, together with the contribution and scope of neutron activation analysis. In part two the technical details of the neutron activation of rats in vivo are determined and the problems raised by application of the method considered. This is followed by an application of neutron activation analysis to research on changes in the nitrogen, chlorine, calcium and phosphorus composition of rats during growth (from 30 to 440 days) and important biological events such as puberty in both sexes, reproduction and lactation. Finally a study of the fertility rate and the effects of repeated irradiations on Sprague-Dawley rats are described

  1. Effects of Potassium and Calcium in Nutrient Solution on Susceptibility of Cut Rose Flowers to Gray Mold

    Directory of Open Access Journals (Sweden)

    SH. Kiani

    2010-04-01

    Full Text Available Gray mold, caused by Botrytis cinerea, is a serious disease of cut rose flowers (Rosa hybrida L. in Iran. In order to elucidate the effects of different potassium and calcium levels in nutrient solution on susceptibility of cut rose flowers to gray mold, this experiment was carried out as factorial design in a randomized complete block with four replications at Safi Abad Agricultural Research center in 2008 for one year. In this experiment, rose plants were grown and subjected to three levels of potassium (1.0, 5.0 and 10.0 mM in combination with two levels of calcium (1.6 and 4.8 mM under hydroponic condition. Rose flowers from two consecutive harvesting periods were sprayed with the conidial suspension (104 spore/ml of B. cinerea isolate. At the end of experiment the disease severity was recorded and analyzed. The results indicated that application of 10.0 mM K in the nutrient solution led to increasing rose disease severity to gray mold (30.4 % day-1 compared to 1.0 mM (24.8 % day-1 and 5.0 mM (26.2 % day-1 of K levels (P< 0.01. The increased susceptibility was associated with a decreased concentration of Ca in the rose petals. Correlation analysis revealed that susceptibility of rose flowers to gray mold significantly increased with K to sum cations ratio in the nutrient solution (r = 0.94*. The increase of Ca supply from 1.6 to 4.8 mM resulted in decline of disease severity from 29.6 to 24.6 % day-1 (P< 0.01. Therefore, balanced application of potassium and calcium (5.0 and 4.8 mM, respectively is recommendable for preventing antagonistic effects between them and reducing of rose gray mold intensity under hydroponic conditions.

  2. Extensive theoretical study on electronically excited states of calcium monochloride: Molecular laser cooling and production of ultracold chlorine atoms

    Science.gov (United States)

    Fu, Mingkai; Ma, Haitao; Cao, Jianwei; Bian, Wensheng

    2016-05-01

    Nine doublet Λ-S states of calcium monochloride (CaCl) are calculated using the internally contracted multireference configuration interaction method with the Davidson correction. Both the core subvalence and spin-orbit coupling effects are taken into account. Laser cooling of CaCl and production of ultracold chlorine atoms are investigated and assessed. Our computed spectroscopic constants and radiative lifetimes match the available experimental data very well. The determined Franck-Condon factors and vibrational branching ratios of the A 2 Π 1 / 2 ( ν ' ) ← X 2 Σ1 / 2 + ( ν ) transition are highly diagonally distributed and the evaluated radiative lifetime for the A2Π1/2(ν' = 0) state is 28.2 ns, which is short enough for rapid laser cooling. Subsequently, detection of cold molecules via resonance enhanced multiphoton ionization to determine the final quantum state populations is discussed and the ionization energy calculated. A multi-pulse excitation scheme is proposed for producing ultracold chlorine atoms from zero-energy photodissociation of the cooled CaCl. Our results demonstrate the possibility of producing ultracold CaCl molecules and Cl atoms.

  3. Extensive theoretical study on electronically excited states of calcium monochloride: Molecular laser cooling and production of ultracold chlorine atoms.

    Science.gov (United States)

    Fu, Mingkai; Ma, Haitao; Cao, Jianwei; Bian, Wensheng

    2016-05-14

    Nine doublet Λ-S states of calcium monochloride (CaCl) are calculated using the internally contracted multireference configuration interaction method with the Davidson correction. Both the core subvalence and spin-orbit coupling effects are taken into account. Laser cooling of CaCl and production of ultracold chlorine atoms are investigated and assessed. Our computed spectroscopic constants and radiative lifetimes match the available experimental data very well. The determined Franck-Condon factors and vibrational branching ratios of the A(2)Π1/2(ν('))←X(2)Σ1/2 (+)(ν) transition are highly diagonally distributed and the evaluated radiative lifetime for the A(2)Π1/2(ν' = 0) state is 28.2 ns, which is short enough for rapid laser cooling. Subsequently, detection of cold molecules via resonance enhanced multiphoton ionization to determine the final quantum state populations is discussed and the ionization energy calculated. A multi-pulse excitation scheme is proposed for producing ultracold chlorine atoms from zero-energy photodissociation of the cooled CaCl. Our results demonstrate the possibility of producing ultracold CaCl molecules and Cl atoms. PMID:27179479

  4. Calcium and potassium content in beef: influences on tenderness and associations with molecular markers in Nellore cattle.

    Science.gov (United States)

    Tizioto, Polyana Cristine; Gromboni, Caio Fernando; Nogueira, Ana Rita de Araujo; de Souza, Marcela Maria; Mudadu, Maurício de Alvarenga; Tholon, Patricia; Rosa, Antônio do Nascimento; Tullio, Rymer Ramiz; Medeiros, Sérgio Raposo; Nassu, Renata Tieko; Regitano, Luciana Correia de Almeida

    2014-01-01

    Calcium (Ca) and potassium (K) are essential nutrients in animal nutrition. Furthermore, the Ca content can influence meat tenderness because it is needed by the proteolytic system of calpains and calpastatins, major factors in postmortem tenderization of skeletal muscles. K content, which is needed for muscle contraction, can also affect meat tenderness. This study showed that K positively affects the Warner-Bratzler shear force (WBSF), measured at 14days of meat aging, which means that higher levels of K are related to lower meat tenderness. Additionally, a significant effect (P≤0.015) of a SNP in the calcium-activated neutral protease 1 (CAPN1) gene on Ca content was observed. Metal content in beef can affect not only nutritional values but also meat quality traits. Part of this effect may be related to variation in specific genes. PMID:23995697

  5. Application of in situ chemical oxidation technique with potassium permanganate for the remediation of a shallow aquifer contaminated with chlorinated solvents

    Directory of Open Access Journals (Sweden)

    Alaine Santos da Cunha

    2012-12-01

    Full Text Available In situ chemical oxidation is a method that is frequently being used for the remediation of contaminated areas, since it presents an adequate efficiency in the reduction of the contaminant mass, particularly chlorinated ethenes, in a relatively short period of time. This manuscript presents the results of the application of this method, using the injection of potassium permanganate as the remediation agent, in an impacted area with chlorinated organic compounds, especially 1,1-dichloroethene. The effectiveness of this remediation method is related to the complexity of the conceptual model of the contaminated site and to the conduction of specific studies in laboratory and pilot tests in field scale, prior to the accomplishment of the full-scale remediation. Therefore, this work contributes presenting a description of the procedures that are commonly used for conducting this kind of studies. In the case under study, it was estimated that the mass of 1.1-dichloroethene (1.1-DCE was reduced from 15.53 to 1.81 kg in groundwater 22 months after the injection of potassium permanganate in the aquifer. The average concentrations of 1.1-DCE in groundwater decreased from 200 to 24 g/L, which value is lower than the environmental standard limit and also to the calculated target of remediation based on human-health risk assessment. Significant contamination rebounds were not identified in the aquifer after the injection of the chemical oxidant. The suitable results of the remediation in this case may be related to the relatively low aquifer heterogeneity and low original concentrations of the contaminant.

  6. Model Vestibular Nuclei Neurons Can Exhibit a Boosting Nonlinearity Due to an Adaptation Current Regulated by Spike-Triggered Calcium and Calcium-Activated Potassium Channels

    Science.gov (United States)

    Schneider, Adam D.

    2016-01-01

    In vitro studies have previously found a class of vestibular nuclei neurons to exhibit a bidirectional afterhyperpolarization (AHP) in their membrane potential, due to calcium and calcium-activated potassium conductances. More recently in vivo studies of such vestibular neurons were found to exhibit a boosting nonlinearity in their input-output tuning curves. In this paper, a Hodgkin-Huxley (HH) type neuron model, originally developed to reproduce the in vitro AHP, is shown to produce a boosting nonlinearity similar to that seen in vivo for increased the calcium conductance. Indicative of a bifurcation, the HH model is reduced to a generalized integrate-and-fire (IF) model that preserves the bifurcation structure and boosting nonliearity. By then projecting the neuron model’s phase space trajectories into 2D, the underlying geometric mechanism relating the AHP and boosting nonlinearity is revealed. Further simplifications and approximations are made to derive analytic expressions for the steady steady state firing rate as a function of bias current, μ, as well as the gain (i.e. its slope) and the position of its peak at μ = μ*. Finally, although the boosting nonlinearity has not yet been experimentally observed in vitro, testable predictions indicate how it might be found. PMID:27427914

  7. Role of arachidonic acid in hyposmotic membrane stretch-induced increase in calcium-activated potassium currents in gastric myocytes

    Institute of Scientific and Technical Information of China (English)

    Meng YANG; Wen-xie XU; Xing-lan LI; Hui-ying XU; Jia-bin SUN; Bin MEI; Hai-feng ZHENG; Lian-hua PIAO; De-gang XING; Zhai-liu LI

    2005-01-01

    Aim: To study effects of arachidonic acid (AA) and its metabolites on the hyposmotic membrane stretch-induced increase in calcium-activated potassium currents (IKCa) in gastric myocytes. Methods: Membrane currents were recorded by using a conventional whole cell patch-clamp technique in gastric myocytes isolated with collagenase. Results: Hyposmotic membrane stretch and AA increased both IK(Ca) and spontaneous transient outward currents significantly.Exogenous AA could potentiate the hyposmotic membrane stretch-induced increase in IK(Ca). The hyposmotic membrane stretch-induced increase in IK(Ca) was significantly suppressed by dimethyleicosadienoic acid (100 μmol/L in pipette solution), an inhibitor of phospholipase A2. Nordihydroguaiaretic acid, a lipoxygenase inhibitor, significantly suppressed AA and hyposmotic membrane stretch-induced increases in IK(Ca). External calcium-free or gadolinium chloride, a blocker of stretch-activated channels, blocked the AA-induced increase in IK(Ca) significantly, but it was not blocked by nicardipine, an L-type calcium channel blocker. Ryanodine, a calcium-induced calcium release agonist, completely blocked the AA-induced increase in IK(Ca); however, heparin, a potent inhibitor of inositol triphosphate receptor, did not block the AA-induced increase in IK(Ca). Conclusion:Hyposmotic membrane stretch may activate phospholipase A2, which hydrolyzes membrane phospholipids to ultimately produce AA; AA as a second messenger mediates Ca2+ influx, which triggers Ca2+-induced Ca2+ release and elicits activation of IK(Ca) in gastric antral circular myocytes of the guinea pig.

  8. Toxic effects of chlorinated organic compounds and potassium dichromate on growth rate and photosynthesis of marine phytoplankton

    DEFF Research Database (Denmark)

    Kusk, Kresten Ole; Nyholm, Niels

    1992-01-01

    The toxic effects of potassium dichromate (K2Cr2O7), 3,4-dichloroaniline (DCA) and 2,4-dichlorophenol (DCP) on the photosynthesis of natural marine phytoplankton and five species of marine microalgae were investigated. Effect concentrations corresponding to a 50 % depression of photosynthesis (6h...

  9. Role of calcium activated potassium channels in atrial fibrillation pathophysiology and therapy

    DEFF Research Database (Denmark)

    Diness, Jonas G.; Bentzen, Bo H.; S. Sørensen, Ulrik;

    2015-01-01

    Small-conductance Ca2+-activated potassium (SK) channels are relative newcomers within the field of cardiac electrophysiology. In recent years, an increased focus has been given to these channels since they might constitute a relatively atrial selective target. The present review will give...

  10. Use of Calcium, Potassium, and Sodium Lactates to Control Germination and Outgrowth of Clostridium perfringens Spores during Chilling of Injected Pork

    Science.gov (United States)

    Inhibition of Clostridium perfringens spore germination and outgrowth by calcium (CaL), potassium (KL) or sodium (NaL) lactate in injected pork during abusive chilling regimes was investigated. Lactates (Ca, K, or Na) were incorporated into injected pork at various concentrations (1.0, 2.0, 3.0 and...

  11. Localization of large conductance calcium-activated potassium channels and their effect on calcitonin gene-related peptide release in the rat trigemino-neuronal pathway

    DEFF Research Database (Denmark)

    Wulf-Johansson, H.; Amrutkar, D.V.; Hay-Schmidt, Anders;

    2010-01-01

    Large conductance calcium-activated potassium (BK(Ca)) channels are membrane proteins contributing to electrical propagation through neurons. Calcitonin gene-related peptide (CGRP) is a neuropeptide found in the trigeminovascular system (TGVS). Both BK(Ca) channels and CGRP are involved in migraine...

  12. Role of calcium-activated potassium channels with small conductance in bradykinin-induced vasodilation of porcine retinal arterioles

    DEFF Research Database (Denmark)

    Dalsgaard, Thomas; Kroigaard, Christel; Bek, Toke;

    2009-01-01

    PURPOSE: Endothelial dysfunction and impaired vasodilation may be involved in the pathogenesis of retinal vascular diseases. In the present study, the mechanisms underlying bradykinin vasodilation were examined and whether calcium-activated potassium channels of small (SK(Ca)) and intermediate (IK......(Ca)) conductance are involved in regulation of endothelium-dependent vasodilation in retinal arterioles was investigated. METHODS: Porcine retinal arterioles (diameter approximately 112 microm, N = 119) were mounted in microvascular myographs for isometric tension recordings. The arterioles were contracted with...... the thromboxane analogue, U46619, and concentration-response curves were constructed for bradykinin and a novel opener of SK(Ca) and IK(Ca) channels, NS309. RESULTS: In U46619-contracted arterioles, bradykinin and NS309 induced concentration-dependent relaxations. In vessels without endothelium...

  13. Observation of Doubly-Excited States in CALCIUM(17+) and Inner Shell-Photoexcitations in Argon, Potassium and Rubidium

    Science.gov (United States)

    Suleiman, Jamal A.

    High resolution X-ray spectroscopy is used to study (A) simultaneous electron-excitation and electron capture in the collision of calcium ions with argon atoms; these studies are important because of the close relationship to dielectronic recombination (DR) which plays an important role in energy-transfer processes in astrophysical and laboratory plasmas; (B) single and double inner-shell photoexcitations of potassium, rubidium and argon; these measurements can lead to very precise tests of electron correlation effects, such as Breit interaction, and QED effects in many electron systems. In the first case, Ca^{18+ } and Ca^{19+} ions from the ATLAS accelerator at Argonne National Laboratory, at energies near 100 MeV, were directed to an argon gas target. X-ray spectra near 3.9 KeV were collected using a high-resolution X-ray spectrometer. We have resolved transitions from doubly-excited 1s2lnl^ ' states to singly-excited 1s ^2nl^' states in lithium -like calcium. Comparison of the experimental wavelengths and intensities with relativistic Hartree-Fock calculations shows very good agreement. In the second case, we have obtained high spectral resolution absorption spectra of potassium near K-, KN -, and KM-edges, rubidium near K- and KO edges, and argon near K-, KM-, and KL-edges. The measurements were made at the X-24A and X-23A2 beamlines at the National Synchrotron Light Source at Brookhaven National Laboratory. Preliminary identifications of most the peaks are made using Dirac Hartree-Fock calculations. Comparisons of the experimental wavelengths and intensities with relativistic Hartree-Fock calculations show very good agreement.

  14. Sodium Permeability of a Cloned Small-Conductance Calcium-Activated Potassium Channel

    OpenAIRE

    Shin, Narae; Soh, Heun; Chang, Sunghoe; Kim, Do Han; Park, Chul-Seung

    2005-01-01

    Small-conductance Ca2+-activated potassium channels (SKCa channels) are heteromeric complexes of pore-forming main subunits and constitutively bound calmodulin. SKCa channels in neuronal cells are activated by intracellular Ca2+ that increases during action potentials, and their ionic currents have been considered to underlie neuronal afterhyperpolarization. However, the ion selectivity of neuronal SKCa channels has not been rigorously investigated. In this study, we determined the monovalent...

  15. Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

    Science.gov (United States)

    Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

    2015-01-01

    Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants. PMID:25388287

  16. Comparative evaluation of a dentifrice containing calcium sodium phosphosilicate to a dentifrice containing potassium nitrate for dentinal hypersensitivity: A clinical study

    Directory of Open Access Journals (Sweden)

    Tanya Satyapal

    2014-01-01

    Full Text Available Background: Calcium sodium phosphosilicate is a recently introduced desensitizing agent which acts by occluding the dentinal tubules and also resists acid decalcification. This study was designed to assess the efficacy of a new toothpaste containing 5% calcium sodium phosphosilicate for the treatment of dentinal hypersensitivity and also compare it with 5% potassium nitrate. Materials and Methods: Sixty patients with the chief complaint of dentinal hypersensitivity were enrolled and randomly divided into two groups. The visual analog scale (VAS scores were taken for water and air stimuli at baseline, 3 weeks after usage of the respective toothpaste, and 3 weeks after discontinuation of the respective toothpaste. Results: Both the groups showed reduction in hypersensitivity scores at 3 weeks and 6 weeks for air stimulus and cold water. The calcium sodium phosphosilicate group, however, showed significantly reduction in hypersensitivity compared to the potassium nitrate group at any time point for both measures of hypersensitivity. Conclusion: The 5% calcium sodium phosphosilicate group showed immense reduction in dentinal hypersensitivity symptoms. The 5% calcium sodium phosphosilicate showed prolonged effects even after discontinuation as compared to 5% potassium nitrate, due to its dentinal tubular occlusion property.

  17. Voltage-gated potassium channel Kvl.3 in rabbit ciliary epithelium regulates the membrane potential via coupling intracellular calcium

    Institute of Scientific and Technical Information of China (English)

    LI Yan-feng; ZHUO Ye-hong; BI Wei-na; BAI Yu-jing; LI Yan-na; WANG Zhi-jian

    2008-01-01

    Background The cell layer of the ciliary epithelium is responsible for aqueous humor secretion and maintenance.Ion channels play an important role in these processes.The main aim of this study was to determine whether the well-characterized members of the Kvl family (Kv1.3) contribute to the Kv currents in ciliary epithelium.Methods New Zealand White rabbits were maintained in a 12 hours light/dark cycle.Ciliary epithelium samples were isolated from the rabbits.We used Western blotting and immunocytochemistry to identify the expression and location of a voltage-gated potassium channel Kvl.3 in ciliary body epithelium.Membrane potential change after adding of Kv1.3 inhibitor margatoxin (MgTX) was observed with a fluorescence method.Results Western blotting and immunocytochemical studies showed that the Kv1.3 protein expressed in pigment ciliary epithelium and nonpigment ciliary epithelium,however it seemed to express more in the apical membrane of the nonpigmented epithelial cells.One nmol/L margatoxin,a specific inhibitor of Kv1.3 channels caused depolarization of the cultured nonpigmented epithelium (NPE) membrane potential.The cytosotic calcium increased after NPE cell depolarization,this increase of cytosolic calcium was partially blocked by 12.5 μmol/L dantrolene and 10 μmol/L nifedipine.These observations suggest that Kv1.3 channels modulate ciliary epithelium potential and effect calcium dependent mechanisms.Conclusion Kv1.3 channels contribute to K+ efflux at the membrane of rabbit ciliary epithelium.

  18. Toxic effects of chlorinated organic compounds and potassium dichromate on growth rate and photosynthesis of marine phytoplankton

    DEFF Research Database (Denmark)

    Kusk, Kresten Ole; Nyholm, Niels

    1992-01-01

    The toxic effects of potassium dichromate (K2Cr2O7), 3,4-dichloroaniline (DCA) and 2,4-dichlorophenol (DCP) on the photosynthesis of natural marine phytoplankton and five species of marine microalgae were investigated. Effect concentrations corresponding to a 50 % depression of photosynthesis (6h...... EC50) were found within relatively narrow ranges of 3.3–7.2 mg/l and 1.5–12 mg/l for DCA and DCP respectively, whereas the sensitivities towards K2Cr2O7 varied much more. The effects of DCA and DCP on the growth rate of some species were also investigated. EC50 values for DCP and DCA were found...

  19. Role of Calcium-activated Potassium Channels in Atrial Fibrillation Pathophysiology and Therapy.

    Science.gov (United States)

    Diness, Jonas G; Bentzen, Bo H; Sørensen, Ulrik S; Grunnet, Morten

    2015-11-01

    Small-conductance Ca(2+)-activated potassium (SK) channels are relative newcomers within the field of cardiac electrophysiology. In recent years, an increased focus has been given to these channels because they might constitute a relatively atrial-selective target. This review will give a general introduction to SK channels followed by their proposed function in the heart under normal and pathophysiological conditions. It is revealed how antiarrhythmic effects can be obtained by SK channel inhibition in a number of species in situations of atrial fibrillation. On the contrary, the beneficial effects of SK channel inhibition in situations of heart failure are questionable and still needs investigation. The understanding of cardiac SK channels is rapidly increasing these years, and it is hoped that this will clarify whether SK channel inhibition has potential as a new anti-atrial fibrillation principle. PMID:25830485

  20. Interactions between pH, potassium, calcium, bromide, and phenol and their effects on the bioluminescence of Vibrio fischeri.

    Science.gov (United States)

    Berglind, Rune; Leffler, Per; Sjostrom, Michael

    2010-01-01

    Little attention has been paid to how the light produced by the bacterium Vibrio fischeri in the Microtox assay is dependent on the concentration of essential ions such as sodium and potassium, and whether the concentrations of these ions affect the sensitivity of the test system to toxic chemicals. Five selected factors, pH, potassium (K(+)), calcium (Ca(2+)), bromide (Br(-)), and phenol (Phe), were simultaneously varied over a set of systematically planned experiments according to a D-optimal design that supported the estimation of a model with linear, quadratic, and two-factor interatcions of the studied factors. The bacterial light production represented by the gamma values in the Microtox assay for the 24 selected combinations of factors was measured at 5 and 15 min. The gamma values varied from negative to positive values greater than 1, indicating stimulation and inhibition of bacterial light production, respectively. The relationship between the gamma values and the factor settings was investigated with multiple linear regression. After 5 min of exposure, the light production was significantly affected by linear and quadratic terms for K(+), pH, and Phe and an interaction between pH and Phe. The situation was more complex after 15 min of exposure, since in addition significant interactions were found for K x Phe and Ca x pH. The tolerance of V. fischeri to Phe was enhanced by increasing the K and Ca concentrations. Data indicate that the ion composition and pH of the sample, as well as the diluents, need to be considered when the toxicity of salts, water samples, and extracts of sediments and soils are tested using commercially certified toxicity test kits. PMID:20574912

  1. Biochemistry of the normal dura mater of the human brain determination of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur and nitrogen contents

    Directory of Open Access Journals (Sweden)

    Horacio M. Canelas

    1969-06-01

    Full Text Available The concentrations of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur, and nitrogen were determined in samples of apparently normal dura mater removed from 18 subjects recently dead by craniocerebral trauma. The average concentrations expressed in dry weight were: water 79.55 g/100 g ± 2.52; sodium 1.63 mequiv/100 g ±0.27; potassium 3.68 mequiv/100 g ± 0.66; calcium 119.84 mg/100 g ± 107.40; phosphorus 68.2 mg/100 g ± 34.5; magnesium 0.61 mequiv/100 g ± 0.37; copper 249.8 /xg/100 g ± 109.4; iron 0.82 mg/100 g ± 0.28; sulfur 490.7 mg/100 g ± 22.5; nitrogen 3.33 g/100 g ± 0.17.

  2. Duration differences of corticostriatal responses in striatal projection neurons depend on calcium activated potassium currents

    Directory of Open Access Journals (Sweden)

    Mario Alberto Arias-García

    2013-10-01

    Full Text Available The firing of striatal projection neurons (SPNs exhibits afterhyperpolarizing potentials (AHPs that determine discharge frequency. They are in part generated by Ca2+-activated K+-currents involving BK and SK components. It has previously been shown that suprathreshold corticostriatal responses are more prolonged and evoke more action potentials in direct pathway SPNs (dSPNs than in indirect pathway SPNs (iSPNs. In contrast, iSPNs generate dendritic autoregenerative responses. Using whole cell recordings in brain slices, we asked whether the participation of Ca2+-activated K+-currents plays a role in these responses. Secondly, we asked if these currents may explain some differences in synaptic integration between dSPNs and iSPNs. Neurons obtained from BAC D1 and D2 GFP mice were recorded. We used charybdotoxin and apamin to block BK and SK channels, respectively. Both antagonists increased the depolarization and delayed the repolarization of suprathreshold corticostriatal responses in both neuron classes. We also used NS 1619 and NS 309 (CyPPA, to enhance BK and SK channels, respectively. Current enhancers hyperpolarized and accelerated the repolarization of corticostriatal responses in both neuron classes. These drugs made evident that the contribution of Ca2+-activated K+-currents was different in dSPNs as compared to iSPNs: in dSPNs their activation was slower as though calcium took a diffusion delay to activate them. In contrast, their activation was fast and then sustained in iSPNs as though calcium flux activates them at the moment of entry. The blockade of Ca2+-activated K+-currents made iSPNs to look as dSPNs. Conversely, their enhancement made dSPNs to look as iSPNs. It is concluded that Ca2+-activated K+-currents are a main intrinsic determinant causing the differences in synaptic integration between corticostriatal polysynaptic responses between dSPNs and iSPNs.

  3. In vivo Spectrophotometric Assessment of the Tooth Whitening Effectiveness of Nite White 10% with Amorphous Calcium Phosphate, Potassium Nitrate and Fluoride, Over a 6-month Period

    OpenAIRE

    Grobler, Sias R; MAJEED, Abdul; Moola, Mohamad H; Rossouw, Roelof J; van Wyk Kotze, Theuns

    2011-01-01

    To clinically evaluate the effectiveness of Nite White 10% carbamide peroxide with amorphous calcium phosphate, potassium nitrate and fluoride over a 6-month follow-up period. Nite White was applied nightly for 14 days, according to the manufacturer’s instructions. The color of teeth 11 and 21 of twenty one subjects was measured with a spectrophotometer (L*; a*; b*). Subjects were instructed to take note of any tooth sensitivity and gingival irritation. For all three components (L*, a* and b*...

  4. Potassium and calcium application ameliorates growth and oxidative homeostasis in salt-stressed indian mustard (brassica juncea) plants

    International Nuclear Information System (INIS)

    The effect of potassium (K) and calcium (Ca) on growth and antioxidant defence system of salt-stressed Indian mustard plants was studied. Twenty-day-old Indian mustard plants grown hydroponically in Hoagland growth medium were randomly divided into five groups. To served as control and did not receive any additional K or Ca (except that present in Hoagland solution), T1 received 150 mM NaCl, T2 was given an additional doze of 6 mM K, T3 was given 5.6 mM Ca as additional doze, while as T4 received a combination of 150 mM NaCl + 6 mM K + 5.6 mM Ca. The response of the plants was studied ten days after treatment. Salt stress inhibited growth parameters including biomass, chlorophyll content, protein content and NR activity. Membrane damage was induced by the salt treatment with a concurrent increase in antioxidant defence system and proline content. Individual application of K and Ca mitigated the negative influence of the stress with the maximum alleviating potential exhibited by the combined application of these nutrients. Results obtained on real time expression of genes encoding enzymatic antioxidants (SOD, APX, CAT and GR), NR and proline supported our findings with biochemical assays. We conclude from the study that maintaining high K and Ca levels may serve as an effective means for regulating the growth and productivity of Indian mustard plants under saline conditions. (author)

  5. Stimulation of beta-adrenoceptors inhibits calcium-dependent potassium-channels in mouse macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Rosati, C.; Hannaert, P.; Dausse, J.P.; Braquet, P.; Garay, R.

    1986-12-01

    K/sup +/ efflux in mouse macrophages exhibited a rate constant (k/sub k/) of 0.67 +/- 0.04 (h)/sup -1/. This was strongly stimulated by increasing concentrations of the Ca/sup 2 +/ ionophore A23187 up to a maximal value of 4.01 +/- 0.25 (h)/sup -1/ with an IC/sub 50/ of 7.6 +/- 1.9 ..mu..M. Similar results were obtained with the Ca/sup 2 +/ ionophore ionomycin. Binding experiments with /sup 3/H-dihydroalprenolol revealed a high density of beta-adrenergic receptors with apparent dissociation constant of 2.03 +/- 0.06 nM. Isoproterenol at a concentration of 10/sup -6/ -10/sup -5/ M induced a two- to threefold stimulation of endogenous levels of cyclic AMP (cAMP). A23187-stimulated K/sup +/ efflux was partially inhibited by (i) stimulation of adenylate cyclase with isoproterenol, forskolin or, PGE/sub 1/; (ii) exogenous cAMP; and (iii) inhibition of phosphodiesterase with MIX (1-methyl-3-isobutylxanthine). Maximal inhibition of K/sup +/ efflux was obtained by simultaneous addition of isoproterenol and MIX. In dose-response curves, the isoproterenol-sensitive K/sup +/ efflux was half-maximally inhibited (IC/sub 50/) with 2-5 x 10/sup -10/ M of isoproterenol concentration. Propranolol was able to completely block the effect of isoproterenol, with an IC/sub 50/ of about 1-2 x 10/sup -7/ M. Isoproterenol and MIX did not inhibit A23187-stimulated K/sup +/ efflux in an incubation medium where NaCl was replaced by sucrose (or choline), suggesting the involvement of an Na/sup +/:Ca/sup 2 +/ exchange mechanism. The results show that stimulation of beta-adrenoceptors in mouse macrophages counter balances the opening of K/sup +/ channels induced by the calcium ionophore A23187. This likely reflects a decrease in cytoslic free calcium content via a cAMP-mediated stimulation of Na/sup +/:Ca/sup 2 +/ exchange.

  6. Nitrogen, phosphorus, potassium, calcium and magnesium release from two compressed fertilizers: column experiments

    Science.gov (United States)

    Fernández-Sanjurjo, M. J.; Alvarez-Rodríguez, E.; Núñez-Delgado, A.; Fernández-Marcos, M. L.; Romar-Gasalla, A.

    2014-12-01

    The objective of this work was to study nutrients release from two compressed nitrogen-potassium-phosphorous (NPK) fertilizers. In the Lourizán Forest Center, tablet-type controlled-release fertilizers (CRF) were prepared by compressing various mixtures of fertilizers without covers or binders. We used soil columns (50 cm long and 7.3 cm inner diameter) that were filled with soil from the surface layer (0-20 cm) of an A horizon corresponding to a Cambic Umbrisol. Tablets of two slow-release NPK fertilizers (11-18-11 or 8-8-16) were placed into the soil (within the first 3 cm), and then water was percolated through the columns in a saturated regime for 80 days. Percolates were analyzed for N, P, K+, Ca2+ and Mg2+. These elements were also determined in soil and fertilizer tablets at the end of the trials. Nutrient concentrations were high in the first leachates and reached a steady state when 1426 mm of water had been percolated, which is equivalent to approximately 1.5 years of rainfall in this geographic area. In the whole trial, both tablets lost more than 80% of their initial N, P and K contents. However, K+, Ca2+ and Mg2+ were the most leached, whereas N and P were lost in leachates to a lesser extent. Nutrient release was slower from the tablet with a composition of 8-8-16 than from the 11-18-11 fertilizer. In view of that, the 8-8-16 tablet can be considered more adequate for crops with a nutrient demand sustained over time. At the end of the trial, the effects of these fertilizers on soil chemical parameters were still evident, with a significant increase of pH, available Ca2+, Mg2+, K+, P and effective cation exchange capacity (eCEC) in the fertilized columns, as well as a significant decrease in exchangeable Al3+, reaching values < 0.08 cmol (+) kg-1.

  7. Bioefficacy of a novel calcium-potassium salt of (-)-hydroxycitric acid

    International Nuclear Information System (INIS)

    Obesity is associated with cardiovascular disease, diabetes and certain forms of cancer. Popular strategies on weight loss often fail to address many key factors such as fat mass, muscle density, bone density, water mass, their inter-relationships and impact on energy production, body composition, and overall health and well-being. (-)-Hydroxycitric acid (HCA), a natural plant extract from the dried fruit rind of Garcinia cambogia, has been reported to promote body fat loss in humans without stimulating the central nervous system. The level of effectiveness of G. cambogia extract is typically attributed solely to HCA. However, other components by their presence or absence may significantly contribute to its therapeutic effectiveness. Typically, HCA used in dietary weight loss supplement is bound to calcium, which results in a poorly soluble (2+/K+ bound (-)-HCA salt (HCA-SX or Super CitriMax) make it completely water soluble as well as bioavailable. An efficacious dosage of HCA-SX (4500 mg/day t.i.d.) provides a good source of Ca2+ (495 mg, 49.5% of RDI) and K+ (720 mg, 15% of RDI). Ca2+ ions are involved in weight management by increasing lipid metabolism, enhancing thermogenesis, and increasing bone density. K+, on the other hand, increases energy, reduces hypertension, increases muscle strength and regulates arrhythmias. Both Ca and K act as buffers in pH homeostasis. HCA-SX has been shown to increase serotonin availability, reduce appetite, increase fat oxidation, improve blood lipid levels, reduce body weight, and modulate a number of obesity regulatory genes without affecting the mitochondrial and nuclear proteins required for normal biochemical and physiological functions

  8. Bioefficacy of a novel calcium-potassium salt of (-)-hydroxycitric acid

    Energy Technology Data Exchange (ETDEWEB)

    Downs, Bernard W. [InterHealth Research Center, Benicia, CA (United States); Bagchi, Manashi [InterHealth Research Center, Benicia, CA (United States); Subbaraju, Gottumukkala V. [Laila Impex Research Center, Vijayawada (India); Shara, Michael A. [Department of Pharmacy Sciences, Creighton University Medical Center, 2500 California Plaza, Omaha, 68178 NE (United States); Preuss, Harry G. [Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC (United States); Bagchi, Debasis [InterHealth Research Center, Benicia, CA (United States) and Department of Pharmacy Sciences, Creighton University Medical Center, 2500 California Plaza, Omaha, 68178 NE (United States)]. E-mail: debsis@creighton.edu

    2005-11-11

    Obesity is associated with cardiovascular disease, diabetes and certain forms of cancer. Popular strategies on weight loss often fail to address many key factors such as fat mass, muscle density, bone density, water mass, their inter-relationships and impact on energy production, body composition, and overall health and well-being. (-)-Hydroxycitric acid (HCA), a natural plant extract from the dried fruit rind of Garcinia cambogia, has been reported to promote body fat loss in humans without stimulating the central nervous system. The level of effectiveness of G. cambogia extract is typically attributed solely to HCA. However, other components by their presence or absence may significantly contribute to its therapeutic effectiveness. Typically, HCA used in dietary weight loss supplement is bound to calcium, which results in a poorly soluble (<50%) and less bioavailable form. Conversely, the structural characteristics of a novel Ca{sup 2+}/K{sup +} bound (-)-HCA salt (HCA-SX or Super CitriMax) make it completely water soluble as well as bioavailable. An efficacious dosage of HCA-SX (4500 mg/day t.i.d.) provides a good source of Ca{sup 2+} (495 mg, 49.5% of RDI) and K{sup +} (720 mg, 15% of RDI). Ca{sup 2+} ions are involved in weight management by increasing lipid metabolism, enhancing thermogenesis, and increasing bone density. K{sup +}, on the other hand, increases energy, reduces hypertension, increases muscle strength and regulates arrhythmias. Both Ca and K act as buffers in pH homeostasis. HCA-SX has been shown to increase serotonin availability, reduce appetite, increase fat oxidation, improve blood lipid levels, reduce body weight, and modulate a number of obesity regulatory genes without affecting the mitochondrial and nuclear proteins required for normal biochemical and physiological functions.

  9. Role of calcium-activated potassium currents in CNP-induced relaxation of gastric antral circular smooth muscle in guinea pigs

    Institute of Scientific and Technical Information of China (English)

    Hui-Shu Guo; Zheng-Xu Cai; Hai-Feng Zheng; Xiang-Lan Li; Yi-Feng Cui; Zuo-Yu Wang; Wen-Xie Xu; Sang-Jin Lee; Young-Chul Kim

    2003-01-01

    AIM: To investigate ion channel mechanism in CNP-induced relaxation of gastric circular smooth muscle in guinea pigs.METHODS: Spontaneous contraction of gastric smooth muscle was recorded by a four -channel physiograph. The whole cell patch-clamp technique was used to record calciumactivated potassium currents and membrane potential in the gastric myocytes isolated by collagenase.RESULTS: C-type natriuretic peptide (CNP) markedly inhibited the spontaneous contraction in a dose-dependent manner in gastric circular smooth muscle in guinea pigs.Ly83583, an inhibitor of guanylate cyclase, weakened CNPinduced inhibition on spontaneous contraction but Zaparinast, an inhibitor of cGMP sensitive phosphoesterase,potentiated CNP-induced inhibition in gastric circular smooth muscles. The inhibitory effects of CNP on spontaneous contraction were blocked by tetrathylammonium (TEA), a nonselective potassium channel blocker. CNP hyperpolarized membrane potential from -60.0 mV±2.0 mV to -68.3 meV±3.0 mV in a single gastric myocyte. CNP increased calcium-activated potassium currents (Ik(ca)) in a dose-dependent manner in gastric circular myocytes. CNP also increased the spontaneously transient outward currents (STOCs). Ly83583 partly blocked CNP-induced increase of calcium-activated potassium currents, but Zaparinast potented the effect.CONCLUSION: CNP inhibits spontaneous contraction, and potassium channel may be involved in the process in gastric circular smooth musde of guinea pigs. CNP-induced increase of Ik(ca) is mediated by a cGMP dependent pathway.

  10. Effects of Ginkgolide B on action potential and calcium,potassium current in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Xiao-yan QI; Zhi-xiong ZHANG; You-qiu XU

    2004-01-01

    AIM: To investigate the effect of Ginkgolide B (GB) on action potential (AP), delayed rectifier potassium current (IK), and L-type calcium current (ICa-L) in guinea pig ventricular myocytes. METHODS: Single ventricular myocytes were isolated by an enzymatic dissociation method. AP, IK, ICa-L were recorded by whole-cell patch-clamp technique in either current or voltage clamp mode. RESULTS: GB shortened APD in a concentration-dependent manner. GB 0.1, 1, and 10 μmol/L shortened APD50 by 7.9 % (n=5, P>0.05), 18.4 % (n=5, P<0.01), and 28.9 % (n=6, P<0.01), respectively; APD90 by 12.4 % (n=5, P>0.05), 17.6 % (n=5, P<0.01), 26.4 % (n=5, P<0.01),respectively. GB increased IK in a concentration-dependent manner. GB 0.1, 1, and l0 μmol/L increased IK by 20.1% (n=6, P<0.05), 43.1% (n=6, P<0.01), 55.6 % (n=6, P<0.05); increased IKtail by 10.7 % (n=6, P<0.05),25.1% (n=6, P<0.05), and 37.7 % (n=6, P<0.05), respectively at testing potential of +50 mV and shift the I-V curve of Ik upward. But GB had no significant effect on ICa-L at above concentrations. CONCLUSION: GB significantly shortened APD in a concentration-dependent manner which mainly due to increase of IK.

  11. Chronic fluoxetine treatment increases NO bioavailability and calcium-sensitive potassium channels activation in rat mesenteric resistance arteries.

    Science.gov (United States)

    Pereira, Camila A; Ferreira, Nathanne S; Mestriner, Fabiola L; Antunes-Rodrigues, José; Evora, Paulo R B; Resstel, Leonardo B M; Carneiro, Fernando S; Tostes, Rita C

    2015-10-15

    Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), has effects beyond its antidepressant properties, altering, e.g., mechanisms involved in blood pressure and vasomotor tone control. Although many studies have addressed the acute impact of fluoxetine on the cardiovascular system, there is a paucity of information on the chronic vascular effects of this SSRI. We tested the hypothesis that chronic fluoxetine treatment enhances the vascular reactivity to vasodilator stimuli by increasing nitric oxide (NO) signaling and activation of potassium (K+) channels. Wistar rats were divided into two groups: (I) vehicle (water for 21 days) or (II) chronic fluoxetine (10 mg/kg/day in the drinking water for 21 days). Fluoxetine treatment increased endothelium-dependent and independent vasorelaxation (analyzed by mesenteric resistance arteries reactivity) as well as constitutive NO synthase (NOS) activity, phosphorylation of eNOS at Serine1177 and NO production, determined by western blot and fluorescence. On the other hand, fluoxetine treatment did not alter vascular expression of neuronal and inducible NOS or guanylyl cyclase (GC). Arteries from fluoxetine-treated rats exhibited increased relaxation to pinacidil. Increased acetylcholine vasorelaxation was abolished by a calcium-activated K+ channel (KCa) blocker, but not by an inhibitor of KATP channels. On the other hand, vascular responses to Bay 41-2272 and 8-bromo-cGMP were similar between the groups. In conclusion, chronic fluoxetine treatment increases endothelium-dependent and independent relaxation of mesenteric resistance arteries by mechanisms that involve increased eNOS activity, NO generation, and KCa channels activation. These effects may contribute to the cardiovascular effects associated with chronic fluoxetine treatment. PMID:26362752

  12. Effects of unsaturated fatty acids on calcium-activated potassium current in gastric myocytes of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    Hai-Feng Zheng; Xiang-Lan Li; Zheng-Yuan Jin; Jia-Bin Sun; Zai-Liu Li; Wen-Xie Xu

    2005-01-01

    AIM: To investigate the effects of exogenous unsaturated fatty acids on calcium-activated potassium current [Ik(Ca)]in gastric antral circular myocytes of guinea pigs.METHODS: Gastric myocytes were isolated by collagenase from the antral circular layer of guinea pig stomach. The whole-cell patch clamp technique was used to record Ik(Ca)in the isolated single smooth muscle cells with or without different concentrations of arachidonic acid (AA), linoleic acid (LA), and oleic acid (OA).RESULTS: AA at concentrations of 2,5 and 10 μmol/L markedly increased IK(ca)in a dose-dependent manner. LA at concentrations of 5, 10 and 20 μmol/L also enhanced IK(Ca)in a dose-dependent manner. The increasing potency of AA, LA, and oleic acid (OA) on Ik(Ca) at the same concentration(10 μmol/L) was in the order of AA>LA>OA. AA (10 μmol/L)-induced increase of Ik(Ca) was not blocked by H-7 (10 μmol/L), an inhibitor of protein kinase C (PKC), or indomethacin (10 μmol/L),an inhibitor of the cyclooxygenase pathway, and 17-octadecynoic acid (10 μmol/L), an inhibitor of the cytochrome P450 pathway, but weakened by nordihydroguaiaretic acid(10 μmol/L), an inhibitor of the lipoxygenase pathway.CONCLUSION: Unsaturated fatty acids markedly increase Ik(Ca), and the enhancing potencies are related to the number of double bonds in the fatty acid chain. The lipoxygenase pathway of unsaturated fatty acid metabolism is involved in the unsaturated fatty acid-induced increase of IK(Ca) in gastric antral circular myocytes of guinea pigs.

  13. S-acylation dependent post-translational cross-talk regulates large conductance calcium- and voltage- activated potassium (BK channels

    Directory of Open Access Journals (Sweden)

    MichaelJShipston

    2014-08-01

    Full Text Available Mechanisms that control surface expression and/or activity of large conductance calcium-activated potassium (BK channels are important determinants of their (pathophysiological function. Indeed, BK channel dysfunction is associated with major human disorders ranging from epilepsy to hypertension and obesity. S-acylation (S-palmitoylation represents a major reversible, post-translational modification controlling the properties and function of many proteins including ion channels. Recent evidence reveals that both pore-forming and regulatory subunits of BK channels are S-acylated and control channel trafficking and regulation by AGC-family protein kinases. The pore-forming α-subunit is S-acylated at two distinct sites within the N- and C-terminus, each site being regulated by different palmitoyl acyl transferases (zDHHCs and acyl thioesterases. (APTs. S-acylation of the N-terminus controls channel trafficking and surface expression whereas S-acylation of the C-terminal domain determines regulation of channel activity by AGC-family protein kinases. S-acylation of the regulatory β4-subunit controls ER exit and surface expression of BK channels but does not affect ion channel kinetics at the plasma membrane. Furthermore, a significant number of previously identified BK-channel interacting proteins have been shown, or are predicted to be, S-acylated. Thus, the BK channel multi-molecular signalling complex may be dynamically regulated by this fundamental post-translational modification and thus S-acylation likely represents an important determinant of BK channel physiology in health and disease.

  14. Genetic control and transgressive segregation of zinc, iron, potassium, phosphorus, calcium, and sodium accumulation in cowpea (Vigna unguiculata) seeds.

    Science.gov (United States)

    Fernandes Santos, C A; Boiteux, L S

    2015-01-01

    Cowpea crop, through combining a range of essential minerals with high quality proteins, plays an important role in providing nutritional security to human population living in semi-arid regions. Studies on genetics of biofortification with essential minerals are still quite scarce, and the major objective of the present study was to provide genetic information on development of cowpea cultivars with high seed mineral contents. Genetic parameters heritability and minimum number of genes were estimated for seed accumulation of zinc (Zn), iron (Fe), calcium (Ca), phosphorus (P), potassium (K), and sodium (Na). Generation mean and variance analyses were conducted using contrasting parental lines, F₁, F₂, and backcross populations derived from IT97K-1042-3 x BRS Tapaihum and IT97K-1042-3 x Canapu crosses. High narrow-sense heritability (h²) values were found for accumulation of Fe (65-86%), P (74-77%), and K (77-88%), whereas moderate h(2) values were observed for accumulation of Ca (41-56%), Zn (51-83%), and Na (50-55%) in seeds. Significant additive genetic effects as well as parental mean effects were detected in both crosses for all minerals, whereas epistasis was important genetic component in Zn content. The minimum number of genes controlling the accumulation of minerals ranged from two (K) to 11 (P). Transgressive segregation was observed in F2 populations of both crosses for all minerals analyzed. The results suggest that, although under either oligogenic or polygenic control, the seed content of these six minerals in cowpea can be improved via standard breeding methods largely used for self-pollinated crops. PMID:25729958

  15. CNTF-Treated Astrocyte Conditioned Medium Enhances Large-Conductance Calcium-Activated Potassium Channel Activity in Rat Cortical Neurons.

    Science.gov (United States)

    Sun, Meiqun; Liu, Hongli; Xu, Huanbai; Wang, Hongtao; Wang, Xiaojing

    2016-08-01

    Seizure activity is linked to astrocyte activation as well as dysfunctional cortical neuron excitability produced from changes in calcium-activated potassium (KCa) channel function. Ciliary neurotrophic factor-treated astrocyte conditioned medium (CNTF-ACM) can be used to investigate the peripheral effects of activated astrocytes upon cortical neurons. However, CNTF-ACM's effect upon KCa channel activity in cultured cortical neurons has not yet been investigated. Whole-cell patch clamp recordings were performed in rat cortical neurons to evaluate CNTF-ACM's effects upon charybdotoxin-sensitive large-conductance KCa (BK) channel currents and apamin-sensitive small-conductance KCa (SK) channel current. Biotinylation and RT-PCR were applied to assess CNTF-ACM's effects upon the protein and mRNA expression, respectively, of the SK channel subunits SK2 and SK3 and the BK channel subunits BKα1 and BKβ3. An anti-fibroblast growth factor-2 (FGF-2) monoclonal neutralizing antibody was used to assess the effects of the FGF-2 component of CNTF-ACM. CNTF-ACM significantly increased KCa channel current density, which was predominantly attributable to gains in BK channel activity (p  0.05). Blocking FGF-2 produced significant reductions in KCa channel current density (p > 0.05) as well as BKα1 and BKβ3 expression in CNTF-ACM-treated neurons (p > 0.05). CNTF-ACM significantly enhances BK channel activity in rat cortical neurons and that FGF-2 is partially responsible for these effects. CNTF-induced astrocyte activation results in secretion of neuroactive factors which may affect neuronal excitability and resultant seizure activity in mammalian cortical neurons. PMID:27097551

  16. De-excitation decay following 1s and 2p shell ionization in Potassium and Calcium atoms using Monte Carlo method

    International Nuclear Information System (INIS)

    Full text; Relative abundance of charged ions and mean charged ions are calculated following 1s and 2p vacancy production in potassium and calcium atoms. The calculations are performed with Monte Carlo simulation method. The simulation based on the tracing of all possible radiation, non-radiation transitions and electron shake off probabilities after inner shell vacancy creation. The radiative transition rates and electron shakes off processes are obtained with Multiconfiguration-Dirac-Fock (MCDF) wave functions model. The non-radiation transition rates are carried out using Dirac-Fock-Slater (DFS) wave functions. At 1s hole states in Potassium atom, the yield of K5+ ions are the prominent produces. The doubly charged K2+ ions predominate over K3+ ions after 2p shell ionization in potassium. On the other hand, the Ca3+ ions dominate over Ca2+ ions in Calcium. The considerations of closing some Coster-Kronig channels and electron shake off processes through the simulation improve the results of charged ions with the experimental data. The results of electron shake off probabilities are compared with other theoretical calculation. The results of relative abundance of charged ions agree well with the experimental data. (author)

  17. Potassium bicarbonate supplementation lowers bone turnover and calcium excretion in older men and women a randomized dose-finding trial

    Science.gov (United States)

    The acid load accompanying modern diets may have adverse effects on bone and muscle metabolism. Treatment with alkaline salts of potassium can neutralize the acid load, but the optimal amount of alkali is not established. Our objective was to determine the effectiveness of two doses of potassium bic...

  18. Effect of Calcium and Potassium on Antioxidant System of Vicia faba L. Under Cadmium Stress

    Directory of Open Access Journals (Sweden)

    Hayssam M. Ali

    2012-05-01

    Full Text Available Cadmium (Cd in soil poses a major threat to plant growth and productivity. In the present experiment, we studied the effect of calcium (Ca2+ and/or potassium (K+ on the antioxidant system, accumulation of proline (Pro, malondialdehyde (MDA, and content of photosynthetic pigments, cadmium (Cd and nutrients, i.e., Ca2+ and K+ in leaf of Vicia faba L. (cv. TARA under Cd stress. Plants grown in the presence of Cd exhibited reduced growth traits [root length (RL plant−1, shoot length (SL plant−1, root fresh weight (RFW plant−1, shoot fresh weight (SFW plant−1, root dry weight (RDW plant−1 and shoot dry weight (SDW plant−1] and concentration of Ca2+, K+, Chlorophyll (Chl a and Chl b content, except content of MDA, Cd and (Pro. The antioxidant enzymes [peroxidase (POD and superoxide dismutase (SOD] slightly increased as compared to control under Cd stress. However, a significant improvement was observed in all growth traits and content of Ca2+, K+, Chl a, Chl b ,Pro and activity of antioxidant enzymes catalase (CAT, POD and SOD in plants subjected to Ca2+ and/or K+. The maximum alleviating effect was recorded in the plants grown in medium containing Ca2+ and K+ together. This study indicates that the application of Ca2+ and/or K+ had a significant and synergistic effect on plant growth. Also, application of Ca2+ and/or K+ was highly effective against the toxicity of Cd by improving activity of antioxidant enzymes and solute that led to the enhanced plant growth of faba bean plants.

  19. Comparative evaluation of human pulp tissue dissolution by different concentrations of chlorine dioxide, calcium hypochlorite and sodium hypochlorite: An in vitro study

    Directory of Open Access Journals (Sweden)

    Sonali Taneja

    2014-01-01

    Full Text Available Introduction: Irrigation plays an indispensable role in removal of tissue remnants and debris from the complicated root canal system. This study compared the human pulp tissue dissolution by different concentrations of chlorine dioxide, calcium hypochlorite and sodium hypochlorite. Materials and Methods: Pulp tissue was standardized to a weight of 9 mg for each sample. In all,60 samples obtained were divided into 6 groups according to the irrigating solution used- 2.5% sodium hypochlorite (NaOCl, 5.25% NaOCl, 5% calcium hypochlorite (Ca(OCl 2 , 10% Ca(OCl 2 , 5%chlorine dioxide (ClO 2 and 13% ClO 2 . Pulp tissue was placed in each test tube carrying irrigants of measured volume (5ml according to their specified subgroup time interval: 30 minutes (Subgroup A and 60 minutes (Subgroup B. The solution from each sample test tube was filtered and was left for drying overnight. The residual weight was calculated by filtration method. Results: Mean tissue dissolution increases with increase in time period. Results showed 5.25% NaOCl to be most effective at both time intervals followed by 2.5% NaOCl at 60 minutes, 10%Ca(OCl 2 and 13% ClO 2 at 60 minutes. Least amount of tissue dissolving ability was demonstrated by 5% Ca(OCl 2 and 5% ClO 2 at 30 minutes. Distilled water showed no pulp tissue dissolution. Conclusion: Withinthe limitations of the study, NaOCl most efficiently dissolved the pulp tissue at both concentrations and at both time intervals. Mean tissue dissolution by Ca(OCl 2 and ClO 2 gradually increased with time and with their increase in concentration.

  20. Vitamin K3 inhibits mouse uterine contraction in vitro via interference with the calcium transfer and the potassium channels.

    Science.gov (United States)

    Zhang, Xian-Xia; Lu, Li-Min; Wang, Li

    2016-08-01

    Previous studies have demonstrated vitamin K3 had a great relief to smooth muscle spastic disorders, but no researches have yet pinpointed its possible anti-contractile activity in the uterus. Here, we evaluated the effect of vitamin K3 on myometrial contractility and explored the possible mechanisms of vitamin K3 action. Myograph apparatus were used to record the changes in contractility of isolated mouse uterine strips in a tissue bath. Uterine strips were exposed to vitamin K3 or vehicle. Vitamin K3 suppressed spontaneous contractions in a concentration dependent manner. It significantly decreased the contractile frequency induced by PGF2ɑ but not their amplitude (expect 58.0 μM). Prior incubation with vitamin K3 reduced the effectiveness of PGF2ɑ-induced contraction. The antispasmodic effect of vitamin K3 was also sensitive to potassium channel blockers, such as tetraethylammonium, 4-aminopyridine, iberiotoxin) but not to the nitric oxide related pathway blockers. High concentrations (29.0, 58.0 μM) of vitamin K3 weakened the Ca(2+) dose response and inhibited phase 1 contraction (intracellular stored calcium release). These dates suggest that vitamin K3 specifically suppresses myometrial contractility by affecting calcium and potassium channels; thus, this approach has potential therapy for uterine contractile activity related disorders. PMID:27237971

  1. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to calcium and potassium and maintenance of normal acid-base balance (ID 400, 407) pursuant to Article 13(1) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    claims in relation to calcium and potassium and maintenance of normal acid-base balance. The scientific substantiation is based on the information provided by the Member States in the consolidated list of Article 13 health claims and references that EFSA has received from Member States or directly from...... stakeholders. The food constituents that are the subject of the health claims are calcium and potassium. The Panel considers that calcium and potassium are sufficiently characterised. The claimed effects are “calcium contributes to acid/base balance within metabolism” and “mineral/potassium: key function......-base balance is a beneficial physiological effect. The Panel notes that no evidence has been provided showing that the dietary intake of calcium and potassium affects normal acid-base balance in the general healthy population. The Panel concludes that a cause and effect relationship has not been established...

  2. In vivo evidence for nitric oxide-mediated calcium-activated potassium-channel activation during human endotoxemia.

    NARCIS (Netherlands)

    Pickkers, P.; Dorresteijn, M.J.; Bouw, M.P.W.J.M.; Hoeven, J.G. van der; Smits, P.

    2006-01-01

    BACKGROUND: During septic shock, the vasoconstrictor response to norepinephrine is seriously blunted. Animal experiments suggest that hyperpolarization of smooth muscle cells by opening of potassium (K) channels underlies this phenomenon. In the present study, we examined whether K-channel blockers

  3. QUANTITATIVE ESTIMATION OF INORGANIC CONTENTS IN VARIETIES OF CAPSICUMANNUUM AND CAPSICUMFRUTESCENCE. I MOISTURE PERCENTAGE, DRY MATTER, SODIUM, POTASSIUM AND CALCIUM

    OpenAIRE

    Sharad S. Phulari

    2014-01-01

    Capsicum annuum varieties Black short, Deonur Bydadagi, Jwala, Pant C-1, Sankeshwari and C. frutescence variety Lavangi are under study. Moisture percentage in roots is less than stem, leaves and fruit of Capsicum varieties. Variety Jwala give highest dry matter of fruit and also reported as high yielding amongst the Capsicum varieties. Variety Jwala is having good capacity of uptake and accumulation of Potassium and thereby yielding maximum economically. Root is one of the thr...

  4. Structural and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from alite hydration in the presence of sodium and potassium hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza, Oscar, E-mail: oamendoz@unal.edu.co [Grupo del Cemento y Materiales de Construcción (CEMATCO). Universidad Nacional de Colombia, Facultad de Minas, Medellín (Colombia); Giraldo, Carolina [Cementos Argos S.A., Medellín (Colombia); Camargo, Sergio S. [Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro (Brazil); Tobón, Jorge I. [Grupo del Cemento y Materiales de Construcción (CEMATCO). Universidad Nacional de Colombia, Facultad de Minas, Medellín (Colombia)

    2015-08-15

    This research evaluates the effect of sodium and potassium hydroxide on the structure and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from the hydration of pure alite. Monoclinic (MIII) alite was synthesized and hydrated, using water-to-alite ratios of 0.5 and 0.6 and additions of 10% NaOH and KOH by weight of alite. Based on results of X-ray diffraction, isothermal calorimetry, thermogravimetric analysis, Nuclear Magnetic Resonance and nanoindentation, two different effects of the alkaline hydroxides on the hydration reaction of alite, both at early and later ages, can be identified: (i) a differentiated hydration process, attributed to an enhancement in calcium hydroxide (CH) precipitation and a stimulation of the C-S-H nuclei; and (ii) an increase in the elastic modulus of the C-S-H aggregations, attributed to an electrostatic attraction between positive charges from the alkaline cations and negative charges from the C-S-H structure.

  5. Structural and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from alite hydration in the presence of sodium and potassium hydroxide

    International Nuclear Information System (INIS)

    This research evaluates the effect of sodium and potassium hydroxide on the structure and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from the hydration of pure alite. Monoclinic (MIII) alite was synthesized and hydrated, using water-to-alite ratios of 0.5 and 0.6 and additions of 10% NaOH and KOH by weight of alite. Based on results of X-ray diffraction, isothermal calorimetry, thermogravimetric analysis, Nuclear Magnetic Resonance and nanoindentation, two different effects of the alkaline hydroxides on the hydration reaction of alite, both at early and later ages, can be identified: (i) a differentiated hydration process, attributed to an enhancement in calcium hydroxide (CH) precipitation and a stimulation of the C-S-H nuclei; and (ii) an increase in the elastic modulus of the C-S-H aggregations, attributed to an electrostatic attraction between positive charges from the alkaline cations and negative charges from the C-S-H structure

  6. Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains

    International Nuclear Information System (INIS)

    In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter

  7. Calcium, potassium, iron, copper and zinc concentrations in the white and gray matter of the cerebellum and corpus callosum in brain of four genetic mouse strains

    Science.gov (United States)

    Sergeant, C.; Vesvres, M. H.; Devès, G.; Guillou, F.

    2005-04-01

    In the central nervous system, metallic cations are involved in oligodendrocyte maturation and myelinogenesis. Moreover, the metallic cations have been associated with pathogenesis, particularly multiple sclerosis and malignant gliomas. The brain is vulnerable to either a deficit or an excess of available trace elements. Relationship between trace metals and myelinogenesis is important in understanding a severe human pathology : the multiple sclerosis, which remains without efficient treatment. One approach to understand this disease has used mutant or transgenic mice presenting myelin deficiency or excess. But to date, the concentration of trace metals and mineral elements in white and gray matter areas in wild type brain is unknown. The aim of this study is to establish the reference concentrations of trace metals (iron, copper and zinc) and minerals (potassium and calcium) in the white and gray matter of the mouse cerebellum and corpus callosum. The brains of four different genetic mouse strains (C57Black6/SJL, C57Black6/D2, SJL and C3H) were analyzed. The freeze-dried samples were prepared to allow PIXE (Proton-induced X-ray emission) and RBS (Rutherford backscattering spectrometry) analyses with the nuclear microprobe in Bordeaux. The results obtained give the first reference values. Furthermore, one species out of the fours testes exhibited differences in calcium, iron and zinc concentrations in the white matter.

  8. Effect of calcium ion on reaction of potassium permanganate and natural organic matter%钙离子对高锰酸钾与天然有机物反应的影响

    Institute of Scientific and Technical Information of China (English)

    王晓荣; 陈忠林; 王斌远; 沈吉敏

    2011-01-01

    利用单宁酸做为天然有机物的代表研究了高锰酸钾与天然有机物的反应,考察了钙离子及钙离子和高锰酸钾不同投加顺序的影响及机理,并利用FTIR对反应进行了光谱学研究.结果表明,高锰酸钾与单宁酸反应生成可溶性分子,钙离子和高锰酸钾不同投加顺序对二者反应有一定的影响,先投加钙离子再投加高锰酸钾,溶液UV276.5的降低较多一些,DOC去除率较高一些,反应较充分.钙离子存在时单宁酸与高锰酸钾反应后生成大量固体成分,FTIR光谱的结果证实了此作用现象和机理.因此钙离子和有机物形成络合物,影响高锰酸钾与水中天然有机物的反应.%The reaction of potassium permanganate and natural organic matter was investigated. Effect of calcium ion and different dosing order of calcium and potassium permanganate were studied. FTIR spectra was employed for further spectroscopy study. Results showed that the reaction product of potassium permanganate and tannic acid were some soluble organic material, different dosing order of calcium and potassium permanganate has effect on the reaction. The addition of potassium permanganate after calcium presented the result of lower UV276.5 and DOC. FTIR spectra results showed that calcium ion increases the quantity of solid product. Consequently, it indicated that calcium ion chelates with organic matter and has important effect on the reaction of potassium permanganate and natural organic material.

  9. Scientific Opinion on the re-evaluation of propionic acid (E 280, sodium propionate (E 281, calcium propionate (E 282 and potassium propionate (E 283 as food additives

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Additives and Nutrient Sources added to food (ANS

    2014-07-01

    Full Text Available The EFSA ANS Panel provides a scientific opinion re-evaluating the safety of propionic acid (E 280, sodium propionate (E 281, calcium propionate (E 282 and potassium propionate (E 283 which are authorised as food additives in the EU and have been previously evaluated by the SCF and JECFA. JECFA allocated an ADI “not limited”. The SCF concluded that potassium propionate could be added to the list of preservatives and established an ADI ”not specified”. Propionates are naturally occurring substances in the normal diet. The Panel considered that forestomach hyperplasia reported in long-term studies in rodents is not a relevant endpoint for humans because humans lack this organ. Based on the reported presence of reversible diffuse epithelial hyperplasia in the oesophagus the LOAEL for a 90-day study in dogs was considered by the Panel to be 1 % propionic acid in the diet and the NOAEL to be 0.3 % propionic acid in the diet. The Panel considered that there is no concern with respect to genotoxicity and carcinogenicity. The Panel concluded that the present database did not allow allocation of an ADI for propionic acid - propionates. The overall mean and 95th percentile exposures to propionic acid - propionates resulting from their use as food additives (major contributor to exposure ranged from 0.7-21.1 and 3.6-40.8 mg/kg bw/day, respectively. The Panel noted that the concentration provoking site of contact effect in the 90-day study in dogs (1 % propionic acid in the diet is a factor of three higher than the concentration of propionic acid - propionates in food at the highest permitted level and concluded that for food as consumed, there would not be a safety concern from the maximum concentrations of propionic acid and its salts at their currently authorised uses and use levels as food additives.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. The small conductance calcium-activated potassium channel 3 (SK3) is a molecular target for Edelfosine to reduce the invasive potential of urothelial carcinoma cells.

    Science.gov (United States)

    Steinestel, Konrad; Eder, Stefan; Ehinger, Konstantin; Schneider, Juliane; Genze, Felicitas; Winkler, Eva; Wardelmann, Eva; Schrader, Andres J; Steinestel, Julie

    2016-05-01

    Metastasis is the survival-determining factor in urothelial carcinoma (UC) of the urinary bladder. The small conductance calcium-activated potassium channel 3 (SK3) enhances tumor cell invasion in breast cancer and malignant melanoma. Since Edelfosine, a glycerophospholipid with antitumoral properties, effectively inhibits SK3 channel activity, our goal was to evaluate SK3 as a potential molecular target to inhibit the gain of an invasive phenotype in UC. SK3 protein expression was analyzed in 208 tissue samples and UC cell lines. Effects of Edelfosine on SK3 expression and intracellular calcium levels as well as on cell morphology, cell survival and proliferation were assessed using immunoblotting, potentiometric fluorescence microscopy, and clonogenic/cell survival assay; furthermore, we analyzed the effect of Edelfosine and SK3 RNAi knockdown on tumor cell migration and invasion in vitro and in vivo. We found that SK3 is strongly expressed in muscle-invasive UC and in the RT112 cellular tumor model. Higher concentrations of Edelfosine have a strong antitumoral effect on UC cells, while 1 μM effectively inhibits migration/invasion of UC cells in vitro and in vivo comparable to the SK3 knockdown phenotype. Taken together, our results show strong expression of SK3 in muscle-invasive UC, consistent with the postulated role of the protein in tumor cell invasion. Edelfosine is able to effectively inhibit migration and invasion of UC cells in vitro and in vivo in an SK3-dependent way, pointing towards a possible role for Edelfosine as an antiinvasive drug to effectively inhibit UC cell invasion and metastasis. PMID:26619845

  12. Thermodynamics and Kinetics of Boron Removal from Metallurgical Grade Silicon by Addition of High Basic Potassium Carbonate to Calcium Silicate Slag

    Science.gov (United States)

    Wu, Jijun; Wang, Fanmao; Ma, Wenhui; Lei, Yun; Yang, Bin

    2016-06-01

    In this study, we investigated the thermodynamics and kinetics of boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag containing a high basic potassium carbonate. The distribution of boron between slag and silicon was theoretically derived and the distribution coefficients ( L B) of boron with different compositions of CaO, SiO2, and K2CO3 in slag reagents were determined. The maximal value of L B reached 2.08 with a high basicity slag of 40 pctCaO-40 pctSiO2-20 pctK2CO3 (Λ = 0.73). The boron removal rates from MG-Si using CaO-SiO2 and CaO-SiO2-K2CO3 slags at 1823 K (1550 °C) were investigated in an electromagnetic induction furnace. The results showed that the boron concentration in MG-Si can be reduced from 22 to 1.8 ppmw at 1823 K (1550 °C) with 20 pct K2CO3 addition to calcium silicate slag, where the removal efficiency of boron reached 91.8 pct. The mass transfer coefficient ( β S) of boron in binary 50 pctCaO-50 pctSiO2 slag was 3.16 × 10-6 m s-1 at 1823 K (1550 °C) and was 2.43 × 10-5 m s-1 in ternary 40 pctCaO-40 pctSiO2-20 pctK2CO3 slag.

  13. Calcium- and voltage-gated potassium (BK) channel activators in the 5β-cholanic acid-3α-ol analogue series with modifications in the lateral chain.

    Science.gov (United States)

    Bukiya, Anna N; Patil, Shivaputra A; Li, Wei; Miller, Duane D; Dopico, Alex M

    2012-10-01

    Large conductance, calcium- and voltage-gated potassium (BK) channels regulate various physiological processes and represent an attractive target for drug discovery. Numerous BK channel activators are available. However, these agents usually interact with the ubiquitously distributed channel-forming subunit and thus cannot selectively target a particular tissue. We performed a structure-activity relationship study of lithocholic acid (LCA), a cholane that activates BK channels via the accessory BK β1 subunit. The latter protein is highly abundant in smooth muscle but scarce in most other tissues. Modifications to the LCA lateral chain length and functional group yielded two novel smooth muscle BK channel activators in which the substituent at C24 has a small volume and a net negative charge. Our data provide detailed structural information that will be useful to advance a pharmacophore in search of β1 subunit-selective BK channel activators. These compounds are expected to evoke smooth muscle relaxation, which would be beneficial in the pharmacotherapy of prevalent human disorders associated with increased smooth muscle contraction, such as systemic hypertension, cerebral or coronary vasospasm, bronchial asthma, bladder hyperactivity, and erectile dysfunction. PMID:22945504

  14. An inducible expression system of the calcium-activated potassium channel 4 to study the differential impact on embryonic stem cells.

    Science.gov (United States)

    Liebau, Stefan; Tischendorf, Michael; Ansorge, Daniel; Linta, Leonhard; Stockmann, Marianne; Weidgang, Clair; Iacovino, Michelina; Boeckers, Tobias; von Wichert, Götz; Kyba, Michael; Kleger, Alexander

    2011-01-01

    Rationale. The family of calcium-activated potassium channels consists of four members with varying biological functions and conductances. Besides membrane potential modulation, SK channels have been found to be involved in cardiac pacemaker cell development from ES cells and morphological shaping of neural stem cells. Objective. Distinct SK channel subtype expression in ES cells might elucidate their precise impact during cardiac development. We chose SK channel subtype 4 as a potential candidate influencing embryonic stem cell differentiation. Methods. We generated a doxycycline inducible mouse ES cell line via targeted homologous recombination of a cassette expressing a bicistronic construct encoding SK4 and a fluorophore from the murine HPRT locus. Conclusion. We characterized the mouse ES cell line iSK4-AcGFP. The cassette is readily expressed under the control of doxycycline, and the overexpression of SK4 led to an increase in cardiac and pacemaker cell differentiation thereby serving as a unique tool to characterize the cell biological variances due to specific SK channel overexpression. PMID:21941566

  15. Method development for the determination of calcium, copper, magnesium, manganese, iron, potassium, phosphorus and zinc in different types of breads by microwave induced plasma-atomic emission spectrometry.

    Science.gov (United States)

    Ozbek, Nil; Akman, Suleyman

    2016-06-01

    A novel method was developed for the determination of calcium, magnesium, potassium, iron, copper, zinc, and manganese and phosphorous in various kinds of breads samples sold in Turkey by microwave plasma-atomic emission spectrometry (MIP-AES). Breads were dried at 100 °C for one day, ground thoroughly and then digested using nitric acid/hydrogen per oxide (3:1). The analytes in certified reference wheat flour and maize flour samples were determined in the uncertainty limits of the certified values as well as the analytes added to the mixture of ground bread and acid mixture prior to digestion were recovered quantitatively (>90%). Therefore, all determinations were made by linear calibration technique using aqueous standards. The LOD values for Ca, Cu, Fe, K, Mg, Mn, P and Zn were 13.1, 0.28, 4.47, 118, 1.10, 0.41, 7550 and 3.00 ng mL(-1), respectively. No spectral interference was detected at the working wavelengths of the analytes. PMID:26830585

  16. Activity diagrams for calcium/hydrogen, sodium/hydrogen, and potassium/hydrogen, and H4SiO4 and their relation to reactions in systems containing radioactive waste forms, cement, and rock in the presence of water

    International Nuclear Information System (INIS)

    In order to identify reactions which can occur in systems containing nuclear waste forms, cement, and repository rock in the presence of water, activity diagrams were calculated from free energies for aluminosilicates and calcium silicates. Groundwater compositions from candidate repository sites in the Palo Duro Basin of Texas, the Delaware Basin of New Mexico, and the Nevada Test Site were plotted on these diagrams. Essentially all of these are shown to be in the calcium zeolite field as shown on the diagram for calcium in the absence of other cations. Chlorite is shown to be stable in this region at the Mg and pH level of the Ogallala if the chlorite is high in iron, and at the Mg and pH level of the Wolfcamp low- or high-Fe chlorites are stable. Potassium and sodium mineral relationships fall in two categories, dilute waters and saline waters. Boreholes at Yucca Flat and Mercury Valley at the Nevada Test Site, and shallow ground water from the Rolling Plains north and east of the Palo Duro Basin are in equilibrium with kaolinite. The brines from the Salado and Rustler formations are in equilibrium with kaolinite and possibly also with sodium-potassium zeolite and illite. Leachates of cement and water, and cement, waste, and water were plotted on the calcium silicate activity diagram. These solutions are in equilibrium with calcium silicate hydrate hydrolysis reactions, with grossular and possibly with Ca-zeolites. Among the calcium silicates, calcium-silicate-hydrate gel (C-S-H gel) and tobermorite are the most likely candidates, but the thermodynamic data are not adequate to distinguish all the possibilities. 37 references, 4 figures, 3 tables

  17. Effects of rapid and slow potassium repolarization currents and calcium dynamics on hysteresis in restitution of action potential duration.

    Science.gov (United States)

    Wu, Runze; Patwardhan, Abhijit

    2007-04-01

    We used a mathematical model to investigate effects of repolarizing currents I(kr) and I(ks), calcium (Ca) current I(CaL), and Ca dynamics in network sarcoplasmic reticulum and junctional sarcoplasmic reticulum (JSR) on hysteresis in restitution of action potential duration. Enhanced I(kr) increased slope of restitution, hysteresis loop thickness, and delay between peaks of diastolic intervals and action potential duration. Increase in I(ks) decreased loop thickness and peak delay. Decrease in I(CaL) had effects similar to increasing I(kr), except slope of restitution decreased markedly. Uptake of Ca into the network sarcoplasmic reticulum had less effect on hysteresis than transfer of Ca into JSR. Faster transfer of Ca into JSR markedly decreased loop thickness and peak delay. Our results provide insight into mechanisms responsible for this newly identified property of restitution. Such information will be valuable in studies where modification of hysteresis is used to investigate its role in arrhythmogenesis. PMID:16895773

  18. Effects of β-hydroxybutyrate and different calcium and potassium concentrations on the membrane potential and motility of abomasal smooth muscle cells in cattle.

    Science.gov (United States)

    Zurr, L; Leonhard-Marek, S

    2012-10-01

    The left displacement of the abomasum (LDA) is a common disease in periparturient dairy cows. Plasma β-hydroxybutyrate (BHBA) levels above the reference range are regarded as risk factors for the occurrence of LDA. Additionally, hypokalemia and hypocalcemia have been observed in LDA cows. The aim of the present study was to characterize the membrane potential and the slow waves in abomasal smooth muscle cells by a microelectrode technique and to determine possible effects of BHBA and of various calcium and potassium concentrations on the membrane potential. Subsequently, the results obtained by the microelectrode technique were combined with in vitro motility experiments of abomasal smooth muscles. Strips of the abomasal circular smooth muscles were prepared and incubated in different buffer solutions. For the microelectrode technique, healthy bulls and cows that underwent surgery for LDA were sampled. These measurements showed a frequency of the slow waves between 3.5 and 10.9 per minute (for amplitudes ≥ 3mV) and between 0.6 and 4.5 per minute (for amplitudes ≥ 5mV). The frequency of contractions (1.8 to 3.1 per minute) were in the same order as the frequency of the slow waves with amplitudes ≥ 5 mV. Blocking potassium conductance with barium chloride induced a depolarization of the basal membrane potential (from -43±2.9 to -37±4.1mV; mean ± standard error of the mean) without affecting the frequency or the height of the slow waves. The reduction in the potassium concentration from 5.4 to 2 mmol/L resulted in a nominal decrease in the activity of contractions (from 22.2 to 18.6 mN/min). The subsequent addition of 1 mmol of KCl/L induced a nominal increase in contraction activity (from 18.6 to 25.7 mN/min). An effect of BHBA (5 mmol/L) could not be demonstrated, neither on the electric nor on the motility parameters. A simulated hypocalcemia (1.2 mmol/L total, 0.9 mmol/L ionized Ca) did not change slow waves and motility. In conclusion, changes in

  19. Cutaneous blood flow during intradermal NO administration in young and older adults: roles for calcium-activated potassium channels and cyclooxygenase?

    Science.gov (United States)

    Fujii, Naoto; Meade, Robert D; Minson, Christopher T; Brunt, Vienna E; Boulay, Pierre; Sigal, Ronald J; Kenny, Glen P

    2016-06-01

    Nitric oxide (NO) increases cutaneous blood flow; however, the underpinning mechanism(s) remains to be elucidated. We hypothesized that the cutaneous blood flow response during intradermal administration of sodium nitroprusside (SNP, a NO donor) is regulated by calcium-activated potassium (KCa) channels and cyclooxygenase (COX) in young adults. We also hypothesized that these contributions are diminished in older adults given that aging can downregulate KCa channels and reduce COX-derived vasodilator prostanoids. In 10 young (23 ± 5 yr) and 10 older (54 ± 4 yr) adults, cutaneous vascular conductance (CVC) was measured at four forearm skin sites infused with 1) Ringer (Control), 2) 50 mM tetraethylammonium (TEA), a nonspecific KCa channel blocker, 3) 10 mM ketorolac, a nonspecific COX inhibitor, or 4) 50 mM TEA + 10 mM ketorolac via intradermal microdialysis. All skin sites were coinfused with incremental doses of SNP (0.005, 0.05, 0.5, 5, and 50 mM each for 25 min). During SNP administration, CVC was similar at the ketorolac site (0.005-50 mM, all P > 0.05) relative to Control, but lower at the TEA and TEA + ketorolac sites (0.005-0.05 mM, all P 0.05). Furthermore, TEA alone did not modulate CVC during any concentration of SNP administration in older adults (all P > 0.05). We show that during low-dose NO administration (e.g., 0.005-0.05 mM), KCa channels contribute to cutaneous blood flow regulation in young adults; however, in older adults, COX inhibition increases cutaneous blood flow through a KCa channel-dependent mechanism. PMID:27053645

  20. Activation of endothelial and epithelial KCa2.3 calcium-activated potassium channels by NS309 relaxes human small pulmonary arteries and bronchioles

    Science.gov (United States)

    Kroigaard, Christel; Dalsgaard, Thomas; Nielsen, Gorm; Laursen, Britt E; Pilegaard, Hans; Köhler, Ralf; Simonsen, Ulf

    2012-01-01

    BACKGROUND AND PURPOSE Small (KCa2) and intermediate (KCa3.1) conductance calcium-activated potassium channels (KCa) may contribute to both epithelium- and endothelium-dependent relaxations, but this has not been established in human pulmonary arteries and bronchioles. Therefore, we investigated the expression of KCa2.3 and KCa3.1 channels, and hypothesized that activation of these channels would produce relaxation of human bronchioles and pulmonary arteries. EXPERIMENTAL APPROACH Channel expression and functional studies were conducted in human isolated small pulmonary arteries and bronchioles. KCa2 and KCa3.1 currents were examined in human small airways epithelial (HSAEpi) cells by whole-cell patch clamp techniques. RESULTS While KCa2.3 expression was similar, KCa3.1 protein was more highly expressed in pulmonary arteries than bronchioles. Immunoreactive KCa2.3 and KCa3.1 proteins were found in both endothelium and epithelium. KCa currents were present in HSAEpi cells and sensitive to the KCa2.3 blocker UCL1684 and the KCa3.1 blocker TRAM-34. In pulmonary arteries contracted by U46619 and in bronchioles contracted by histamine, the KCa2.3/ KCa3.1 activator, NS309, induced concentration-dependent relaxations. NS309 was equally potent in relaxing pulmonary arteries, but less potent in bronchioles, than salbutamol. NS309 relaxations were blocked by the KCa2 channel blocker apamin, while the KCa3.1 channel blocker, charybdotoxin failed to reduce relaxation to NS309 (0.01–1 µM). CONCLUSIONS AND IMPLICATIONS KCa2.3 and KCa3.1 channels are expressed in the endothelium of human pulmonary arteries and epithelium of bronchioles. KCa2.3 channels contributed to endo- and epithelium-dependent relaxations suggesting that these channels are potential targets for treatment of pulmonary hypertension and chronic obstructive pulmonary disease. PMID:22506557

  1. A contribution of research by chlorination from nickel silicate and nickel ferrite in the presence of calcium chloride and coke with possibilities of their intensification

    OpenAIRE

    Krstev, Boris

    1988-01-01

    The previous investigations in the field of the metal compounds chlorination of the refractory nickel minerals: garnierite and nontronite, by the chlorine, Cl2, HCl, NaCl or CaCl2, were determined directions, confirming the perspective of the mentioned process for the treatment of the low grade and complex minerals-laterites. The existing combined methods for enriching of the oxide-silicate nickel ores are these through which by heating the ore with coke and CaCl2 at high temperature reduced...

  2. Stimulation of large-conductance calcium-activated potassium channels inhibits neurogenic contraction of human bladder from patients with urinary symptoms and reverses acetic acid-induced bladder hyperactivity in rats.

    Science.gov (United States)

    La Fuente, José M; Fernández, Argentina; Cuevas, Pedro; González-Corrochano, Rocío; Chen, Mao Xiang; Angulo, Javier

    2014-07-15

    We have analysed the effects of large-conductance calcium-activated potassium channel (BK) stimulation on neurogenic and myogenic contraction of human bladder from healthy subjects and patients with urinary symptoms and evaluated the efficacy of activating BK to relief bladder hyperactivity in rats. Bladder specimens were obtained from organ donors and from men with benign prostatic hyperplasia (BPH). Contractions elicited by electrical field stimulation (EFS) and carbachol (CCh) were evaluated in isolated bladder strips. in vivo cystometric recordings were obtained in anesthetized rats under control and acetic acid-induced hyperactive conditions. Neurogenic contractions of human bladder were potentiated by blockade of BK and small-conductance calcium-activated potassium channels (SK) but were unaffected by the blockade of intermediate calcium-activated potassium channels (IK). EFS-induced contractions were inhibited by BK stimulation with NS-8 or NS1619 or by SK/IK stimulation with NS309 (3µM). CCh-induced contractions were not modified by blockade or stimulation of BK, IK or SK. The anti-cholinergic agent, oxybutynin (0.3µM) inhibited either neurogenic or CCh-induced contractions. Neurogenic contractions of bladders from BPH patients were less sensitive to BK inhibition and more sensitive to BK activation than healthy bladders. The BK activator, NS-8 (5mg/kg; i.v.), reversed bladder hyperactivity induced by acetic acid in rats, while oxybutynin was ineffective. NS-8 did not significantly impact blood pressure or heart rate. BK stimulation specifically inhibits neurogenic contractions in patients with urinary symptoms and relieves bladder hyperactivity in vivo without compromising bladder contractile capacity or cardiovascular safety, supporting its potential therapeutic use for relieving bladder overactivity. PMID:24747752

  3. ٍEffect of potassium and calcium application on water use and fruit yield of tomato in a hydroponic system with dynamic and non-uniform distribution of salts

    OpenAIRE

    A.A. Moezzi; A. H. Khoshgoftarmanesh; M. Koushafar; M. Mobli

    2012-01-01

    One of the problems for unequal distribution of salts in the root media is toxicity of sodium (Na) and reduced uptake of some nutrients, particularly calcium (Ca) and potassium (K), by the roots growing in the saline section. There is a hypothesis that addition of Ca and K to these systems might alleviate salt-induced damages to plants. This study was carried out to evaluate the effect of Ca and K application on fruit yield, water use and crop per drop (CPD) of tomato (Lycopersicon esculentum...

  4. Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by Ajay Europe SARL

    OpenAIRE

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)

    2013-01-01

    Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two ...

  5. Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by HELM AG

    OpenAIRE

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)

    2013-01-01

    Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two ...

  6. Calcium and Potassium Supplementation Enhanced Growth, Osmolyte Secondary Metabolite Production, and Enzymatic Antioxidant Machinery in Cadmium-Exposed Chickpea (Cicer arietinum L.)

    Science.gov (United States)

    Ahmad, Parvaiz; Abdel Latef, Arafat A.; Abd_Allah, Elsayed F.; Hashem, Abeer; Sarwat, Maryam; Anjum, Naser A.; Gucel, Salih

    2016-01-01

    This work examined the role of exogenously applied calcium (Ca; 50 mM) and potassium (K; 10 mM) (alone and in combination) in alleviating the negative effects of cadmium (Cd; 200 μM) on growth, biochemical attributes, secondary metabolites and yield of chickpea (Cicer arietinum L.). Cd stress significantly decreased the length and weight (fresh and dry) of shoot and root and yield attributes in terms of number of pods and seed yield (vs. control). Exhibition of decreases in chlorophyll (Chl) a, Chl b, and total Chl was also observed with Cd-exposure when compared to control. However, Cd-exposure led to an increase in the content of carotenoids. In contrast, the exogenous application of Ca and K individually as well as in combination minimized the extent of Cd-impact on previous traits. C. arietinum seedlings subjected to Cd treatment exhibited increased contents of organic solute (proline, Pro) and total protein; whereas, Ca and K-supplementation further enhanced the Pro and total protein content. Additionally, compared to control, Cd-exposure also caused elevation in the contents of oxidative stress markers (hydrogen peroxidase, H2O2; malondialdehyde, MDA) and in the activity of antioxidant defense enzymes (superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX; glutathione reductase, GR). Ca, K, and Ca + K supplementation caused further enhancements in the activity of these enzymes but significantly decreased contents of H2O2 and MDA, also that of Cd accumulation in shoot and root. The contents of total phenol, flavonoid and mineral elements (S, Mn, Mg, Ca and K) that were also suppressed in Cd stressed plants in both shoot and root were restored to appreciable levels with Ca- and K-supplementation. However, the combination of Ca + K supplementation was more effective in bringing the positive response as compared to individual effect of Ca and K on Cd-exposed C. arietinum. Overall, this investigation suggests that application of Ca and/or K can

  7. The influence of various doses of phosphorus and of the addition of calcium or potassium fertilization upon the yield of tomatoes in Wrocław hydroponic culture using two intensities of light

    Directory of Open Access Journals (Sweden)

    Z. Gumicka

    2013-12-01

    Full Text Available Two experiments were carried out with phosphate fertilization of tomatoes in hydroponic culture. It has been proved that an additional dose of phosphorus given during the second cluster bloom, caused an yield increase. The optimal dose is 12 g of superphosphate (16% P2O5 per plant. The "green back" symptoms did not appear in these conditions. The parallel additional applying of calcium or potassium gave a decrease of the yield. When the light intensity was lowered to about 50%, the yield has decreased by half. In these conditions an additional applying of calcium (0,4 g CaCO3 and phosphorus (1g superphosphate annulated the negative influence of the low light intensity.

  8. Potassium Iodide

    Science.gov (United States)

    Potassium iodide is used to protect the thyroid gland from taking in radioactive iodine that may be released during ... the thyroid gland. You should only take potassium iodide if there is a nuclear radiation emergency and ...

  9. Effectiveness of acidic calcium sulfate with propionic and lactic acid and lactates as postprocessing dipping solutions to control Listeria monocytogenes on frankfurters with or without potassium lactate and stored vacuum packaged at 4.5 degrees C.

    Science.gov (United States)

    Nuñez de Gonzalez, Maryuri T; Keeton, Jimmy T; Acuff, Gary R; Ringer, Larry J; Lucia, Lisa M

    2004-05-01

    The safety of ready-to-eat meat products such as frankfurters can be enhanced by treating with approved antimicrobial substances to control the growth of Listeria monocytogenes. We evaluated the effectiveness of acidic calcium sulfate with propionic and lactic acid, potassium lactate, or lactic acid postprocessing dipping solutions to control L. monocytogenes inoculated (ca. 10(8) CFU/ml) onto the surface of frankfurters with or without potassium lactate and stored in vacuum packages at 4.5 degrees C for up to 12 weeks. Two frankfurter formulations were manufactured without (control) or with potassium lactate (KL, 3.3% of a 60% [wt/wt] commercially available syrup). After cooking, chilling, and peeling, each batch was divided into inoculated (four strains of L. monocytogenes mixture) and noninoculated groups. Each group was treated with four different dips: (i) control (saline solution), (ii) acidic calcium sulfate with propionic and lactic acid (ACS, 1:2 water), (iii) KL, or (iv) lactic acid (LA, 3.4% of a 88% [wt/wt] commercially available syrup) for 30 s. Noninoculated frankfurters were periodically analyzed for pH, water activity, residual nitrite, and aerobic plate counts (APCs), and L. monocytogenes counts (modified Oxford medium) were determined on inoculated samples. Surface APC counts remained at or near the lower limit of detection (dip, which indicated a residual bactericidal effect when L. monocytogenes populations were monitored over 12 weeks. L. monocytogenes numbers were also reduced, but not to the same degree in franks made without or with KL and treated with LA. These results revealed the effectiveness of ACS (bactericidal effect) or LA (bacteriostatic effect) as postprocessing dipping solutions to inhibit or control the growth of L. monocytogenes on vacuum-packaged frankfurters stored at 4.5 degrees C for up to 12 weeks. PMID:15151227

  10. Discovery of novel tetrahydroisoquinoline derivatives as orally active N-type calcium channel blockers with high selectivity for hERG potassium channels.

    Science.gov (United States)

    Ogiyama, Takashi; Inoue, Makoto; Honda, Shugo; Yamada, Hiroyoshi; Watanabe, Toshihiro; Gotoh, Takayasu; Kiso, Tetsuo; Koakutsu, Akiko; Kakimoto, Shuichiro; Shishikura, Jun-ichi

    2014-12-15

    N-type calcium channels represent a promising target for the treatment of neuropathic pain. The selective N-type calcium channel blocker ziconotide ameliorates severe chronic pain but has a narrow therapeutic window and requires intrathecal administration. We identified tetrahydroisoquinoline derivative 1a as a novel potent N-type calcium channel blocker. However, this compound also exhibited potent inhibitory activity against hERG channels. Structural optimizations led to identification of (1S)-(1-cyclohexyl-3,4-dihydroisoquinolin-2(1H)-yl)-2-{[(1-hydroxycyclohexyl)methyl]amino}ethanone ((S)-1h), which exhibited high selectivity for hERG channels while retaining potency for N-type calcium channel inhibition. (S)-1h went on to demonstrate in vivo efficacy as an orally available N-type calcium channel blocker in a rat spinal nerve ligation model of neuropathic pain. PMID:25456079

  11. Influence of calcium-dependent potassium channel blockade and nitric oxide inhibition on norepinephrine-induced contractions in two forms of genetic hypertension

    Czech Academy of Sciences Publication Activity Database

    Líšková, Silvia; Petrová, M.; Karen, Petr; Kuneš, Jaroslav; Zicha, Josef

    2010-01-01

    Roč. 4, č. 3 (2010), s. 128-134. ISSN 1933-1711 R&D Projects: GA AV ČR(CZ) IAA500110902 Institutional research plan: CEZ:AV0Z50110509 Keywords : potassium channels * nitric oxide * norepinephrine Subject RIV: ED - Physiology Impact factor: 0.931, year: 2010

  12. The heart and potassium: a banana republic.

    Science.gov (United States)

    Khan, Ehsan; Spiers, Christine; Khan, Maria

    2013-03-01

    The importance of potassium in maintaining stable cardiac function is a clinically understood phenomenon. Physiologically the importance of potassium in cardiac function is described by the large number of different kinds of potassium ions channels found in the heart compared to channels and membrane transport mechanisms for other ions such as sodium and calcium. Potassium is important in physiological homeostatic control of cardiac function, but is also of relevance to the diseased state, as potassium-related effects may stabilize or destabilize cardiac function. This article aims to provide a detailed understanding of potassium-mediated cardiac function. This will help the clinical practitioner evaluate how modulation of potassium ion channels by disease and pharmacological manipulation affect the cardiac patient, thus aiding in decision making when faced with clinical problems related to potassium. PMID:23425010

  13. Hydrochloric acid recycling from chlorinated hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Sowieja, D. [Sulzer Escher Wyss GmbH, Ravensburg (Germany); Schaub, M. [Sulzer Chemtech Ltd., Winterthur (Switzerland)

    1993-12-31

    Chlorinated hydrocarbons present a major ecological hazard since most of them are only poorly biodegradable. Incineration is an economical process for their destruction, however the usually recovered sodium or calcium chlorides do not present a value and their disposal may even be very costly. Recovery of hydrochloric acid may therefore present an economical solution, mainly were large quantities of highly chlorinated compounds can be processed (author) 6 refs., 4 figs., 1 tab.

  14. Hybrid selective surface hydrophilization and froth flotation separation of hazardous chlorinated plastics from E-waste with novel nanoscale metallic calcium composite.

    Science.gov (United States)

    Mallampati, Srinivasa Reddy; Heo, Je Haeng; Park, Min Hee

    2016-04-01

    Treatment by a nanometallic Ca/CaO composite has been found to selectively hydrophilize the surface of polyvinyl chloride (PVC), enhancing its wettability and thereby promoting its separation from E-waste plastics by means of froth flotation. The treatment considerably decreased the water contact angle of PVC, by about 18°. The SEM images of the PVC plastic after treatment displayed significant changes in their surface morphology compared to other plastics. The SEM-EDS results reveal that a markedly decrease of [Cl] concentration simultaneously with dramatic increase of [O] on the surface of the PCV samples. XPS results further confirmed an increase of hydrophilic functional groups on the PVC surface. Froth flotation at 100rpm mixing speed was found to be optimal, separating 100% of the PVC into a settled fraction of 96.4% purity even when the plastics fed into the reactor were of nonuniform size and shape. The total recovery of PVC-free plastics in E-waste reached nearly 100% in the floated fraction, significantly improved from the 20.5wt% of light plastics that can be recovered by means of conventional wet gravity separation. The hybrid method of nanometallic Ca/CaO treatment and froth flotation is effective in the separation of hazardous chlorinated plastics from E-waste plastics. PMID:26685121

  15. Process for preparation of potassium-38. [DOE patent application

    Science.gov (United States)

    Lambrecht, R.M.; Wolf, A.P.

    A solution of potassium-38 suitable for use as a radiopharmaceutical and a method for its production. Argon is irradiated with protons having energies above the threshold for the /sup 40/Ar(p,3n)/sup 38/K reaction. The resulting potassium-38 is dissolved in a sterile water and any contaminating chlorine-38 is removed.

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

    NARCIS (Netherlands)

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

    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

  17. Calcium addition in straw gasification

    DEFF Research Database (Denmark)

    Risnes, H.; Fjellerup, Jan Søren; Henriksen, Ulrik Birk;

    2003-01-01

    The present work focuses on the influence of calcium addition in gasification. The inorganic¿organic element interaction as well as the detailed inorganic¿inorganic elements interaction has been studied. The effect of calcium addition as calcium sugar/molasses solutions to straw significantly...... affected the ash chemistry and the ash sintering tendency but much less the char reactivity. Thermo balance test are made and high-temperature X-ray diffraction measurements are performed, the experimental results indicate that with calcium addition major inorganic¿inorganic reactions take place very late...... calcium binds silicon primarily as calcium silicates and less as potassium calcium silicates....

  18. Potassium test

    Science.gov (United States)

    ... also be done if your provider suspects metabolic acidosis (for example, caused by uncontrolled diabetes) or alkalosis ( ... Hypoaldosteronism (very rare) Kidney failure Metabolic or respiratory acidosis Red blood cell destruction Too much potassium in ...

  19. Alleviating negative effects of irrigation-water salinity on growth and vase life of gerbera by foliar spray of calcium chloride and potassium silicate

    OpenAIRE

    A. Mohammadi Torkashvand

    2015-01-01

    The required water for greenhouses in Kishestan, Soume-e-Sara town, Guilan province, Iran, is mainly provided by underground resources that have inappropriate quality. One way to reduce the impact of salinity an plant growth is proper nutrition. This greenhouse research was conducted to evaluate the effect of water salinity and foliar spray of calcium (Ca) and silicon (Si) on growth and vase life of gerbera in a factorial experiment based on compeletly randomized design with two factors. The ...

  20. 阿米洛利对豚鼠心肌细胞钾电流及钙电流的作用%Effects of amiloride on potassium and calcium currents in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    程岚; 王芳; 周红义; 姚伟星; 夏国瑾; 江明性

    2004-01-01

    目的研究阿米洛利(amiloride)对豚鼠心肌细胞钾电流及钙电流的作用.方法采用全细胞膜片钳技术记录豚鼠心室肌细胞钾通道及钙通道电流.结果阿米洛利在10~100μmol·L-1抑制L型及T型钙电流,不改变钙电流I-V曲线的形状,仅抑制这两型电流的幅度.当累积浓度达l00μmol·L-1时,阿米洛利轻微抑制快激活延迟整流钾电流(IKr),对慢激活延迟整流钾电流(IKs)无影响.阿米洛利在1~100μmol·L-1浓度依赖性地抑制内向整流钾电流(IK1).结论阿米洛利抑制电压依赖性的钾、钙电流,为其抗心律失常作用提供了离子基础.%Aim To elucidate the possible mechanisms underlying antiarrhythmia of the non-selective Na*/H + exchanger inhibitor- amiloride. Methods Single ventricular cells were isolated using a double-enzyme method. Effects of amiloride on voltage-dependent potassium and calcium currents in isolated guinea pig ventricular myocyte were recorded by using whole-cell patch clamp techniques. Results Amiloride resulted in a concentration-dependent inhibition of peak ICa,L, But amiloride did not change the shape of their I - V curves. It only decreased the amplitudes of the currents of the two types. When Amiloride depressed potassium and calcium currents, which may give support to its uses in some diseases of the cardiovascular system.

  1. Effects of motilin on potassium and calcium currents of rat's proximal colon smooth muscle cells%胃动素对大鼠近端结肠平滑肌细胞钙钾电流的影响

    Institute of Scientific and Technical Information of China (English)

    吴增祐; 罗和生; 梁成柏; 刘颖; 夏虹

    2012-01-01

    Objective To investigate the effects of motilin on the voltage dependent potassium channel and L-type calcium channel currents in rat proximal colon smooth muscle cells (PCSM) and to explore its mechanism in increasing colonic motility.Methods PCSM were isolated by collagenase.The voltage dependent potassium channel transit outward current (IKA ) and delayed rectifier current (IKdr) and L-type calcium currents (ICa(L)) were measured by whole cell patch clamp technique.Groups were analyzed by paired t-test.Results There was no significant effect of motilin on IKA and IKdr.L-type calcium channel was dose-dependently activated by motilin from 0.5 × 105 mmol/L to 10.0 ×10-5 mmol/L.At 6 × 10-5 mmol/L motilin and under - 10,0 and 10 mV stimulating voltage,maximum current density increased by 154.61%,62.69% and 21.02% respectively and activation kinetics curve obviously left shifted.Half activation voltage decreased from (2.740±1.211) mV prior administration to ( - 25.290 ± 0.614) mV (t =8.534,P =0.007 ) and there was no significant difference in slope factor. Conclusions Motilin increases colonic smooth muscle contraction by promoting calcium influx. However the frequency of colonic smooth muscle contraction could not change with frequency of equilibrium potential and action potential of colonic smooth muscle.%目的 研究胃动素对大鼠近端结肠平滑肌细胞(PCSM)膜电压依赖性钾通道及L型钙通道电流的影响,以探讨其增强结肠运动的机制.方法 采用酶解法分离大鼠PCSM,采用全细胞模式膜片钳技术测定PCSM电压依赖性钾离子通道快速激活型钾电流及延迟整流型钾电流和L型钙电流,组间比较采用配对t检验.结果 胃动素对快速激活型钾电流及延迟整流型钾电流无明显作用.(0.5~10.0)×10-5 mmol/L胃动素浓度依赖性地激活L型钙电流,6×10-5 mmol/L胃动素在-10、0及10 mV刺激电压下,使最大电流密度分别增加154.61%、62.69%及21.02%,激

  2. Determination of the physiological plasmatic values of sodium, potassium and ion calcium and its pre and post exercise Variations in “paso fino” horses in the bogota savannah

    Directory of Open Access Journals (Sweden)

    Camila Valdés Restrepo

    2010-12-01

    Full Text Available This research intends to be a contribution to the Colombian sports equine medicine by providing data on electrolytes standards, a field where there is a substantial lack of literature. This research analyze and determines the normal values of sodium (Na+,potassium (K+ and ion calcium (iCa2+ electrolytes for Colombian Paso Fine horses. The establishment of the reference intervals was done at rest and after exercise. To achieve this, blood samples were taken from farms located in the Bogotá savannah. The 115 mares and stallions used for this study were actively competing with ages ranging from 43 to 78 months old. The samples were taken at three intervals: T0 (Rest,T1 (immediately after 45 minutes of exercise, and T2(1 hour post exercise. The samples were processed using a portable blood analyzer i-STAT® and the data was interpreted using descriptive and comparative statistic according to Turkey tests. The normal values for the breed were established and an electrolytic behavior curve was created, using values inside interval sat 95% confidence levels. The values obtained inmEq/L were: for T0: Na+ (136,71+/-0,23, K+ (4,05+/-0,03, Ca2+ (1,58+/-0,006; for T1: Na+ (136,44+/-0,24, K+ (3,92+/-0,24, Ca2+ (1,42+/-0,008; and for T2: Na+ (137,32+/-0,23, K+ (3,68+/-0,03, Ca2+(1,51+/-0,009. Na+ values increased after exercise. On the contrary K+ and Ca2+ values didn’t increase inT1. Calcium increased on T2 and K+ decreased. The findings of this research will serve as a framework for future analysis. Moreover, further studies and developments in this field are recommended and will prove to be very useful for equine practitioners.

  3. Opening of small and intermediate calcium-activated potassium channels induces relaxation mainly mediated by nitric-oxide release in large arteries and endothelium-derived hyperpolarizing factor in small arteries from rat

    DEFF Research Database (Denmark)

    Stankevicius, Edgaras; Dalsgaard, Thomas; Kroigaard, Christel;

    2011-01-01

    current, and NO release that were blocked by apamin and TRAM-34 or charybdotoxin. These findings suggest that opening of SK(Ca) and IK(Ca) channels leads to endothelium-dependent relaxation that is mediated mainly by NO in large mesenteric arteries and by EDHF-type relaxation in small mesenteric arteries......This study was designed to investigate whether calcium-activated potassium channels of small (SK(Ca) or K(Ca)2) and intermediate (IK(Ca) or K(Ca)3.1) conductance activated by 6,7-dichloro-1H-indole-2,3-dione 3-oxime (NS309) are involved in both nitric oxide (NO) and endothelium......-derived hyperpolarizing factor (EDHF)-type relaxation in large and small rat mesenteric arteries. Segments of rat superior and small mesenteric arteries were mounted in myographs for functional studies. NO was recorded using NO microsensors. SK(Ca) and IK(Ca) channel currents and mRNA expression were investigated in...

  4. Potassium Iodide (KI)

    Science.gov (United States)

    ... Planning Information on Specific Types of Emergencies Potassium Iodide (KI) Language: English Español (Spanish) Recommend on Facebook ... I get KI (potassium iodide)? What is Potassium Iodide (KI)? KI (potassium iodide) is a salt of ...

  5. Transmembrane sodium and potassium gradients modulate histamine secretion induced by ionophore A23187.

    OpenAIRE

    Amellal, M.; Bronner, C.; Landry, Y.

    1985-01-01

    Histamine secretion was induced from rat peritoneal mast cells by calcium ionophore A23187 in the presence of various extracellular calcium concentrations. Transmembrane sodium and potassium gradients were altered by cold pretreatment of mast cells or through the inhibition of sodium-potassium ATPase by the use of ouabain or potassium-deprivation. Such pretreatments led to a parallel shift to the left of the extracellular calcium concentration-histamine secretion curve, i.e. to an apparent de...

  6. Phosphate valorization by dry chlorination route

    Directory of Open Access Journals (Sweden)

    Kanari N.

    2016-01-01

    Full Text Available This work deals with the extraction of phosphorus chlorinated compounds from phosphate materials using chlorination with gaseous chlorine. An industrial sample of dicalcium phosphate dihydrate, after transformation into calcium pyrophosphate (Ca2P2O7, is subjected to reactions with Cl2+CO+N2 and Cl2+C+N2 at temperatures ranging from 625 to 950°C using boat experiments. Gathering results of the thermodynamic predictions and TG/DT analysis with those of SEM and XRD examinations of the chlorinated residues allowed the interpretation of phenomena and reactions mechanism occurring during the calcium pyrophosphate carbochlorination. Reaction rate of Ca2P2O7 by Cl2+CO+N2 at 950°C is slowed down due to the formation of a CaCl2 liquid layer acting as a barrier for the diffusion of the reactive gases and further reaction progress. While, the carbochlorination with Cl2+C+N2 led to almost full chlorination of Ca2P2O7 at 750°C and the process proceeds with an apparent activation energy of about 104 kJ/mol between 625 and 750°C. Carbochlorination technique can be considered as an alternative and selective route for the valorization of low grade phosphates and for the phosphorus extraction from its bearing materials.

  7. Treatment of algae-induced tastes and odors by chlorine, chlorine dioxide and permanganate

    OpenAIRE

    Buffin, Lisa Webster

    1992-01-01

    Chlorine (C12(sq»' chlorine dioxide (Cl02 ) and potassium permanganate (KMn04) were evaluated as oxidants for the removal of grassy and cucumber odors associated with the pure compounds, cis-3-hexenol and trans-2, cis-6-nonadienal, respectively, and for the removal of fishy odors associated with a culture of an alga, Synura petersenii. The effects of the oxidants on the pure compounds were assessed both by Flavor Profile Analysis (FPA) and gas chromatography/mass spectrometry (GC/MS). The ef...

  8. Alleviating negative effects of irrigation-water salinity on growth and vase life of gerbera by foliar spray of calcium chloride and potassium silicate

    Directory of Open Access Journals (Sweden)

    A. Mohammadi Torkashvand

    2015-11-01

    Full Text Available The required water for greenhouses in Kishestan, Soume-e-Sara town, Guilan province, Iran, is mainly provided by underground resources that have inappropriate quality. One way to reduce the impact of salinity an plant growth is proper nutrition. This greenhouse research was conducted to evaluate the effect of water salinity and foliar spray of calcium (Ca and silicon (Si on growth and vase life of gerbera in a factorial experiment based on compeletly randomized design with two factors. The first factor was salinity of irrigation water at two levels (0 and 1.5 dS/m and the second factor was foliar spray at seven levels (without spray, twice Ca spray, four times Ca spray, two times Ca spray + once Si spray, twice Ca spray + twice Si spray, four times Ca spray + once Si spray, and four times Ca spray + twice Si spray, each with three replications. Results showed that four times Ca foliar spray led to an increase in stem hight, stem and neck diameter, postharvest life and Ca concentration of shoots. In all spray treatments, number of flowers in zero salinity was more than 1.5 dS/m treatments. In general, in case of using low-quality water (electrical conductivity of 1.5 dS/m, the effects of salinity on dry and fresh weights of gerbera plant and vase life of its flowers can be reduced by foliar application of Ca and Si. Since inappropriate water quality in Rasht Greenhouse Complex, Soume-e-Sara town, is one of the main problems of the farmers, especially in growing the ornamental plants, effects of salinity on plant growth could be alleviated with foliar spray of nutrients, especially Ca and Si. In this respect, four times spray of Ca and also twice spray of Ca + twice spray of Si are recommended.

  9. Potassium clavulanate

    Directory of Open Access Journals (Sweden)

    Kotaro Fujii

    2010-08-01

    Full Text Available The title salt, K+·C8H8NO5− [systematic name: potassium (2R,5R,Z-3-(2-hydroxyethylidene-7-oxo-4-oxa-1-azabicyclo[3.2.0]heptane-2-carboxylate], a widely used β-lactam antibiotic, is usually chemically unstable even in the solid state owing to its tendency to be hydrolysed. In the crystal structure, the potassium cations are arranged along the a axis, forming interactions to the carboxylate and hydroxy groups, resulting in one-dimensional ionic columns. These columns are arranged along the b axis, connected by O—H...O hydrogen bonds, forming a layer in the ab plane.

  10. Effects of cisplatin on potassium currents in CT26 cells

    Directory of Open Access Journals (Sweden)

    Naveen Sharma

    2016-01-01

    Conclusion: Potassium currents were detected in CT26 cells and the currents were reduced by the application of tetraethylammonium (TEA chloride, iberiotoxin, a big conductance calcium-activated potassium channel blocker and barium. The potassium currents were enhanced to 192< by the application of cisplatin (0.5 mM. Moreover, the increase of potassium currents by cisplatin was further inhibited by the application of TEA confirming the action of cisplatin on potassium channels. In addition, relative current induced by cisplatin in CT26 cells was bit larger than in normal IEC-6 cells.

  11. Scientific Opinion on the safety and efficacy of iodine compounds (E2 as feed additives for all species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by HELM AG

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-02-01

    Full Text Available Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day and for toddlers (200 µg/day would be exceeded by a factor of 2 and  4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold. The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg.

  12. ICP-OES法同时测定燕麦片中的钾、钠、钙、镁、铁、锌%Simultaneous determination of potassium, sodium, calcium, magnesium, iron, zinc in oatmeal with ICP-OES

    Institute of Scientific and Technical Information of China (English)

    孙丽萍; 张素娟; 梁宝爱

    2015-01-01

    The determination method of potassium, sodium, calcium, magnesium, iron, zinc in oatmeal was established by the optimization of ICP-AES instruments conditions, with three different digestion methods. The results show that the linear relationship of each element elements is good, the correlation coefficient is above 0.999 9, the relative standard deviation is 1.5%~3.3% and the recovery rate is 82.3%~ 109.4%. The method is operated conveniently, with high accuracy and good precision. The test results of both the method (ICP-OES) and the national standard method are consistent, with no significant difference, and suitable for determination of mineral element in oatmeal.%通过对ICP-OES仪器条件的优化,采用3种不同消解方法,建立了燕麦片中钾、钠、钙、镁、铁、锌各元素的测定方法。试验结果表明,该方法中各元素的线性关系良好,相关系数均在0.9999以上,其相对标准偏差为1.5%~3.3%,回收率为82.3%~109.4%。该方法操作便捷、准确度高、精密度好,与国标方法比较检测结果一致,无显著性差异,适用于燕麦片中矿物质元素的测定。

  13. Scientific Opinion on the safety and efficacy of iodine compounds (E2 as feed additives for all animal species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by Ajay Europe SARL

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-02-01

    Full Text Available Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day and for toddlers (200 µg/day would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold. The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg.

  14. Technology assessment: Chlorine chemistry

    International Nuclear Information System (INIS)

    Chlorine is not just one of many chemical feedstocks which is used in a few definitely harmful products like PVC or CFC but is irrelevant in all other respects. Just the opposite is true: There is hardly any product line of the chemical industry that can do without chlorine, from herbicides and pesticides to dyes, plastics, pharmaceuticals, photographic atricles, and cosmetics. Chlorine is not only a key element of chemical production but also an ubiquitous element of everyday life in civilisation. There are even many who would agree that the volume of chlorine production is an indicator of the competitive strength and national wealth of a modern society. By now, however, it has become evident that the unreflected use of chlorine is no longer ecologically acceptable. The consequences of a chlorine phase-out as compared to the continued chlorine production at the present level were investigated scientifically by a PROGNOS team. They are presented in this book. (orig.)

  15. Physicochemical action of potassium-magnesium citrate in nephrolithiasis

    Science.gov (United States)

    Pak, C. Y.; Koenig, K.; Khan, R.; Haynes, S.; Padalino, P.

    1992-01-01

    Effect of potassium-magnesium citrate on urinary biochemistry and crystallization of stone-forming salts was compared with that of potassium citrate at same dose of potassium in five normal subjects and five patients with calcium nephrolithiasis. Compared to the placebo phase, urinary pH rose significantly from 6.06 +/- 0.27 to 6.48 +/- 0.36 (mean +/- SD, p less than 0.0167) during treatment with potassium citrate (50 mEq/day for 7 days) and to 6.68 +/- 0.31 during therapy with potassium-magnesium citrate (containing 49 mEq K, 24.5 mEq Mg, and 73.5 mEq citrate per day). Urinary pH was significantly higher during potassium-magnesium citrate than during potassium citrate therapy. Thus, the amount of undissociated uric acid declined from 118 +/- 61 mg/day during the placebo phase to 68 +/- 54 mg/day during potassium citrate treatment and, more prominently, to 41 +/- 46 mg/day during potassium-magnesium citrate therapy. Urinary magnesium rose significantly from 102 +/- 25 to 146 +/- 37 mg/day during potassium-magnesium citrate therapy but not during potassium citrate therapy. Urinary citrate rose more prominently during potassium-magnesium citrate therapy (to 1027 +/- 478 mg/day from 638 +/- 252 mg/day) than during potassium citrate treatment (to 932 +/- 297 mg/day). Consequently, urinary saturation (activity product) of calcium oxalate declined significantly (from 1.49 x 10(-8) to 1.03 x 10(-8) M2) during potassium-magnesium citrate therapy and marginally (to 1.14 x 10(-8) M2) during potassium citrate therapy.(ABSTRACT TRUNCATED AT 250 WORDS).

  16. Influence of drinking water treatments on chlorine dioxide consumption and chlorite/chlorate formation.

    Science.gov (United States)

    Sorlini, Sabrina; Gialdini, Francesca; Biasibetti, Michela; Collivignarelli, Carlo

    2014-05-01

    Disinfection is the last treatment stage of a Drinking Water Treatment Plant (DWTP) and is carried out to maintain a residual concentration of disinfectant in the water distribution system. Chlorine dioxide (ClO2) is a widely used chemical employed for this purpose. The aim of this work was to evaluate the influence of several treatments on chlorine dioxide consumption and on chlorite and chlorate formation in the final oxidation/disinfection stage. A number of tests was performed at laboratory scale employing water samples collected from the DWTP of Cremona (Italy). The following processes were studied: oxidation with potassium permanganate, chlorine dioxide and sodium hypochlorite, coagulation/flocculation with ferric chloride and aluminum sulfate, filtration and adsorption onto activated carbon. The results showed that the chlorine dioxide demand is high if sodium hypochlorite or potassium permanganate are employed in pre-oxidation. On the other hand, chlorine dioxide leads to the highest production of chlorite and chlorate. The coagulation/flocculation process after pre-oxidation shows that chlorine dioxide demand decreases if potassium permanganate is employed as an oxidant, both with ferric chloride and aluminum sulfate. Therefore, the combination of these processes leads to a lower production of chlorite and chlorate. Aluminum sulfate is preferable in terms of the chlorine dioxide demand reduction and minimization of the chlorite and chlorate formation. Activated carbon is the most effective solution as it reduced the chlorine dioxide consumption by about 50% and the DBP formation by about 20-40%. PMID:24534637

  17. 钾通道阻断剂4-氨基吡啶诱导海马CA1锥体神经元钙瞬变%Calcium transient of CA1 pyramidal neurons induced by potassium blocker 4-aminopyridine in acute hippocampal slices

    Institute of Scientific and Technical Information of China (English)

    苏涛; 丛文东; 廖卫平

    2011-01-01

    Objective To investigate the calcium transient of CA1 pyramidal neurons induced by potassium blocker 4-aminopyridine (4-AP) in acute hippocampal slices to explore the relation between potassium channel function and calcium transient, and their mechanism. Methods Fluorescent probe was employed to mark the hippocampai neurons in acute brain slices of rats; confocal microscopy was used to perform calcium imaging to observe the influences of different concentrations of 4-AP and perfusate with/without calcium on calcium transient of CA1 pyramidal neurons. Results The response of [Ca2+]I to lower concentration of 4-AP (<15 mmol/L) was in a dose-dependent manner (r2=0.910, P=0.000); the higher the concentration of 4-AP (20-80 mmol/L), the lower the peak level of calcium transient. The latency and amplitude of calcium transient induced by 4-AP were obviously reduced when the extracellular condition was switched to an absence of calcium, which was significantly different as compared with that with calcium (P<0.05). Conclusion Blockade of potassium channels with 4-AP can increase [Ca2+]I in the hippocampal pyramidal neurons of acute slices. The increase of [Ca2+]1 to 4-AP could be ascribe to calcium release from intracellular stores and calcium influx from extracellular matrix.%目的 研究4-氨基吡啶(4-AP)诱导的急性脑片海马CA1锥体神经元钙瞬变现象,探讨钾通道功能与钙瞬变的关系及可能机制.方法 荧光探针标记正常大鼠急性脑片海马神经元.共聚焦显微镜技术进行钙成像,观察不同浓度4-AP及细胞灌流液条件对神经元钙瞬变的影响.结果 低浓度(<15 mmol/L)4-AP诱导的钙瞬变峰值与剂量呈线性相关(r2=0.910,P=0.000),高浓度(20~80 mmol/L)4-AP诱导的钙瞬变峰值随浓度增高而下降.在无钙灌流液条件下,4-AP诱导的钙瞬变峰值水平下降,达峰时间延长,与含钙灌流液比较差异有统计学意义(P<0.05).结论 4-AP可诱导急性脑片海马CA1锥体神经

  18. Atividade de microrganismos solubilizadores de fosfatos na presença de nitrogênio, ferro, cálcio e potássio Phosphate solubilizing activity of microorganisms in the presence of nitrogen, iron, calcium and potassium

    Directory of Open Access Journals (Sweden)

    Germano Nunes Silva Filho

    2001-12-01

    Full Text Available A capacidade e o potencial de solubilização de 21 isolados de microrganismos solubilizadores de fosfatos (Bacillus, Pseudomonas, Enterobacteriaceae, Penicillium, Aspergillus e Paecilomyces foram avaliados em cultivos em meio de cultura Glicose-Extrato de Levedura contendo diferentes fosfatos (Ca, Al ou Fe, na presença de fontes de N (peptona, amônio e nitrato e teores de Fe, Ca e K. O crescimento e a atividade solubilizadora variaram em função do tipo de microrganismo e dos fatores nutricionais. Em relação às fontes de N, a presença de amônio favoreceu a solubilização em seis isolados; destes, três solubilizaram somente nesta fonte. O nitrato diminuiu a atividade solubilizadora, reduzindo ou inibindo a solubilização. Para a maioria dos microrganismos, a atividade solubilizadora não foi afetada pelas variações nos teores de ferro. Baixos teores de Ca e K limitaram o crescimento de cinco isolados que apresentam características de amplo crescimento (Aspergillus. Em dois desses isolados, a solubilização de fosfato de Ca foi favorecida. Variações na capacidade e no potencial de solubilização dos microrganismos, em resposta às condições do meio de cultura, indicam que o processo ocorre com eficiência variável ou sugerem a presença de diferentes mecanismos de solubilização.Twenty-one isolates of phosphate solubilizing microorganisms (Bacillus, Pseudomonas, Enterobacteriaceae, Penicillium, Aspergillus and Paecilomyces were evaluated for their solubilizing capacity and potential in broth media (Glucose-Yeast Extract amended with different types of phosphates (Ca, Al or Fe, in the presence of N sources (peptone, ammonium and nitrate as well as concentrations of Fe, Ca and potassium. Microbial growth and phosphate solubilizing activity varied according to the microorganism and the nutrient supplied. Ammonium increased solubilization activity of six isolates and three of these solubilized only in this source. Nitrate

  19. Calcium and potassium silicates and the growth of Eucalyptus grandis seedlings Aplicação de silicatos de cálcio e de potássio e o crescimento de mudas de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    Itamar Antonio Bognola

    2011-06-01

    Full Text Available

    The use of silicate is a practice that has been frequently adopted in annual crops, although few studies have been conducted in order to verify its efficiency in forest tree species. The main objective of this research was to evaluate the effect of calcium and potassium silicates in the growth of seedlings of Eucalyptus grandis. The experiment was conducted in a greenhouse, in Alambari county, State of São Paulo. A completely randomized experimental design was adopted, with eight treatments, three replications and 25 plants per plot, maintained at the field capacity moisture level. Seedlings were planted in plastic tubes using local substrate, basic fertilization and silicates. Diameter, height and fresh and dry biomass of the seedlings were determined 150 days after silicates treatments were applied. The use of silicates either in the substrate or through foliar application, in the production of eucalypt seedlings has proven to be inadequate when the substrate presents a balanced basic composition in terms of nutrients and pH.

    doi: 10.4336/2011.pfb.31.66.83

    O uso de silicato é uma prática que vem sendo adotada com frequência em culturas anuais, muito embora poucos trabalhos tenham sido realizados com intuito de verificar sua eficiência em espécies florestais arbóreas. O objetivo principal desta pesquisa foi avaliar o efeito da aplicação de silicatos de cálcio e de potássio no crescimento de mudas de Eucalyptus grandis. O experimento foi conduzido em casa de vegetação, no Município de Alambari, SP. O delineamento usado foi inteiramente ao acaso, com oito tratamentos, três repetições e 25 plantas por parcela, sendo mantidas na umidade de capacidade de campo. As mudas foram plantadas em tubetes de plástico, utilizando substrato local, com adubação básica e silicatos. Diâmetro de colo, altura e biomassa verde e seca das mudas foram determinados 150 dias após a

  20. ٍEffect of potassium and calcium application on water use and fruit yield of tomato in a hydroponic system with dynamic and non-uniform distribution of salts

    Directory of Open Access Journals (Sweden)

    A.A. Moezzi

    2012-03-01

    Full Text Available One of the problems for unequal distribution of salts in the root media is toxicity of sodium (Na and reduced uptake of some nutrients, particularly calcium (Ca and potassium (K, by the roots growing in the saline section. There is a hypothesis that addition of Ca and K to these systems might alleviate salt-induced damages to plants. This study was carried out to evaluate the effect of Ca and K application on fruit yield, water use and crop per drop (CPD of tomato (Lycopersicon esculentum var. Falcato F1 plants grown in a hydroponic system with unequal distribution of salts in the root media. Tomato roots were divided into two equal splits and one half was immersed in the full Johnson nutrient solution. In the other root half, 40 mM NaCl solution, alone or in combination with KCl (6 mM, CaCl2 (4 mM, K+Ca (3+2 mM or half-strength Johnson nutrient solution, was applied. A control treatment was also used in which both root splits were immersed in the Johnson nutrient solution (C. The root splits were exchanged every 7 days. Results showed that addition of 40 mM NaCl in one side of the root media resulted in reduction of fresh and dry weight of root and shoot, stem diameter, shoot height, number of leaves and fruit yield of tomato in comparison with the control treatment. Addition of Ca, K+Ca and half-strength Johnson nutrient solution to the saline part of the root media increased significantly the root and shoot growth and fruit yield of tomato compared with the sole application of saline solution. In contrast, addition of K could not alleviate the adverse effects of salinity and even reduced the fruit yield. Application of 40 mM NaCl in one side of the root media reduced significantly the plant water use. Addition of Ca, K+Ca and half-strength Johnson nutrient solution to the saline part of the root media resulted in significant increase in CPD. Addition of Ca, K+Ca and half-strength Johnson nutrient solution caused replacement of 48, 43 and 43

  1. Calcium D-saccharate

    DEFF Research Database (Denmark)

    Garcia, André Castilho; Hedegaard, Martina Vavrusova; Skibsted, Leif Horsfelt

    2016-01-01

    Molar conductivity of saturated aqueous solutions of calcium d-saccharate, used as a stabilizer of beverages fortified with calcium d-gluconate, increases strongly upon dilution, indicating complex formation between calcium and d-saccharate ions, for which, at 25 °C, Kassoc = 1032 ± 80, ΔHassoc......° = -34 ± 6 kJ mol-1, and ΔSassoc° = -55 ± 9 J mol-1 K-1, were determined electrochemically. Calcium d-saccharate is sparingly soluble, with a solubility product, Ksp, of (6.17 ± 0.32) × 10-7 at 25 °C, only moderately increasing with the temperature: ΔHsol° = 48 ± 2 kJ mol-1, and ΔSassoc° = 42 ± 7 J mol-1...... K-1. Equilibria in supersaturated solutions of calcium d-saccharate seem only to adjust slowly, as seen from calcium activity measurements in calcium d-saccharate solutions made supersaturated by cooling. Solutions formed by isothermal dissolution of calcium d-gluconate in aqueous potassium d...

  2. Localization and pharmacological characterization of voltage dependent calcium channels in cultured neocortical neurons

    DEFF Research Database (Denmark)

    Timmermann, D B; Lund, Trine Meldgaard; Belhage, B;

    2001-01-01

    The physiological significance and subcellular distribution of voltage dependent calcium channels was defined using calcium channel blockers to inhibit potassium induced rises in cytosolic calcium concentration in cultured mouse neocortical neurons. The cytosolic calcium concentration was measured...... using the fluorescent calcium chelator fura-2. The types of calcium channels present at the synaptic terminal were determined by the inhibitory action of calcium channel blockers on potassium-induced [3H]GABA release in the same cell preparation. L-, N-, P-, Q- and R-/T-type voltage dependent calcium...... most important voltage dependent calcium channel in all parts of the neuron. After treatment with thapsigargin the increase in cytosolic calcium was halved, indicating that calcium release from thapsigargin sensitive intracellular calcium stores is an important component of the potassium induced rise...

  3. Water Treatment Technology - Chlorination.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on chlorination provides instructional materials for nine competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purpose and process of chlorination, chlorine…

  4. Chlorine solar neutrino experiment

    International Nuclear Information System (INIS)

    The chlorine solar neutrino experiment in the Homestake Gold Mine is described and the results obtained with the chlorine detector over the last fourteen years are summarized and discussed. Background processes producing 37Ar and the question of the constancy of the production rate of 37Ar are given special emphasis

  5. Effect of silica fume addition on the PGNAA measurement of chlorine in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, A.A. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)], E-mail: aanaqvi@kfupm.edu.sa; Maslehuddin, M. [Center for Engineering Research, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Garwan, M.A. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Nagadi, M.M. [Center for Engineering Research, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Al-Amoudi, O.S.B. [Department of Civil Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Raashid, M.; Khateeb-ur-Rehman [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2010-03-15

    Pozzolanic materials, such as fly ash (FA), silica fume (SF), and blast furnace slag (BFS) are added to Portland cement in concrete to prevent reinforcement steel corrosion in concrete. Further preventive measure against reinforcement steel corrosion require monitoring of chloride salts concentration in concrete using non-destructive techniques, such as the prompt gamma-ray neutron activation analysis (PGNAA) technique. Due to interferences between gamma-rays from chlorine and calcium in PGNAA technique, detection limit of chlorine in concrete strongly depends upon calcium concentration in concrete. SF mainly contains silica and its addition to cement concrete reduces overall concentration of calcium in concrete. This may result in an improvement in detection limit of chlorine in SF-based concrete in PGNAA studies. Particularly for chlorine detection using 6.11 and 6.62 MeV prompt gamma-rays that strongly interfere with 6.42 MeV prompt gamma-rays from calcium. In this study, SF was added to Portland cement to prevent concrete reinforcement steel from corrosion. The chlorine concentration in SF cement concrete specimens containing 0.2-3.0 wt% chlorine was measured through yield of 1.16, 1.95, 6.11, 6.62, 7.41, 7.79, and 8.58 MeV chlorine gamma-rays using PGNAA technique. An excellent agreement was noted between the experimental yield of the prompt gamma-rays and the gamma-ray yield calculated through the Monte Carlo simulations. Further the minimum detectable concentration (MDC) of chlorine in SF cement concrete was calculated and compared with the MDC values of chlorine in plain concrete and concrete mixed with fly ash cement. The MDC of chlorine in SF-based concrete through 6.11 MeV, and 6.62 MeV chlorine gamma-rays was found to be improved as compared to those in plain concrete and concrete mixed with fly ash cement.

  6. Effect of silica fume addition on the PGNAA measurement of chlorine in concrete

    International Nuclear Information System (INIS)

    Pozzolanic materials, such as fly ash (FA), silica fume (SF), and blast furnace slag (BFS) are added to Portland cement in concrete to prevent reinforcement steel corrosion in concrete. Further preventive measure against reinforcement steel corrosion require monitoring of chloride salts concentration in concrete using non-destructive techniques, such as the prompt gamma-ray neutron activation analysis (PGNAA) technique. Due to interferences between gamma-rays from chlorine and calcium in PGNAA technique, detection limit of chlorine in concrete strongly depends upon calcium concentration in concrete. SF mainly contains silica and its addition to cement concrete reduces overall concentration of calcium in concrete. This may result in an improvement in detection limit of chlorine in SF-based concrete in PGNAA studies. Particularly for chlorine detection using 6.11 and 6.62 MeV prompt gamma-rays that strongly interfere with 6.42 MeV prompt gamma-rays from calcium. In this study, SF was added to Portland cement to prevent concrete reinforcement steel from corrosion. The chlorine concentration in SF cement concrete specimens containing 0.2-3.0 wt% chlorine was measured through yield of 1.16, 1.95, 6.11, 6.62, 7.41, 7.79, and 8.58 MeV chlorine gamma-rays using PGNAA technique. An excellent agreement was noted between the experimental yield of the prompt gamma-rays and the gamma-ray yield calculated through the Monte Carlo simulations. Further the minimum detectable concentration (MDC) of chlorine in SF cement concrete was calculated and compared with the MDC values of chlorine in plain concrete and concrete mixed with fly ash cement. The MDC of chlorine in SF-based concrete through 6.11 MeV, and 6.62 MeV chlorine gamma-rays was found to be improved as compared to those in plain concrete and concrete mixed with fly ash cement.

  7. Improved Synthesis Of Potassium Beta' '-Alumina

    Science.gov (United States)

    Williams, Roger M.; Jeffries-Nakamura, Barbara; Ryan, Margaret A.; O'Connor, Dennis E.; Kisor, Adam; Underwood, Mark

    1996-01-01

    Improved formulations of precursor materials synthesize nearly-phase-pure potassium beta' '-alumina solid electrolyte (K-BASE) powder. Materials are microhomogeneous powders (or, alternatively, gels) containing K(+,) Mg(2+), and Al(3+). K-BASE powder produced used in potassium-working-fluid alkali-metal thermal-to-electric conversion (K-AMTEC), in which heat-input and heat-rejection temperatures lower than sodium-working-fluid AMTEC (Na-AMTEC). Additional potential use lies in purification of pottassium by removal of sodium and calcium.

  8. [Inactivation of the chlorine-resistant bacteria isolated from the drinking water distribution system].

    Science.gov (United States)

    Chen, Yu-Qiao; Duan, Xiao-Di; Lu, Pin-Pin; Wang, Qian; Zhang, Xiao-Jian; Chen, Chao

    2012-01-01

    Inactivation experiments of seven strains of chlorine-resistant bacteria, isolated from a drinking water distribution system, were conducted with four kinds of disinfectants. All the bacteria showed high resistance to chlorine, especially for Mycobacterium mucogenicum. The CT value of 99.9% inactivation for M. mucogenicum, Sphingomonas sanguinis and Methylobacterium were 120 mg x (L x min)(-1), 7 mg x (L x min)(-1) and 4 mg x (L x min)(-1), respectively. The results of inactivation experiments showed that chlorine dioxide and potassium monopersulfate could inactive 5 lg of M. mucogenicum within 30 min, which showed significantly higher efficiency than free chlorine and monochloramine. Free chlorine was less effective because the disinfectant decayed very quickly. Chloramination needed higher concentration to meet the disinfection requirements. The verified dosage of disinfectants, which could effectively inactivate 99.9% of the highly chlorine-resistant M. mucogenicum within 1 h, were 3.0 mg/L monochloramine, 1.0 mg/L chlorine dioxide (as Cl2), and 1.0 mg/L potassium monopersulfate (as Cl2). It was suggested that the water treatment plants increase the concentration of monochloramine or apply chlorine dioxide intermittently to control the disinfectant-resistant bacteria. PMID:22452196

  9. Effect of Calcium Lactate on Quality, Safety and Nutritional Senescence Parameters of Minimally Processed Vegetables

    OpenAIRE

    Martin-Diana, Ana Belen; Rico, Daniel; Frias, Jesus Maria; Mulcahy, Jemina; Henehan, Gary; Barry-Ryan, Catherine

    2005-01-01

    Calcium lactate maintained quality senescence indicators, as well as chlorine in Iceberg lettuce, and enhanced nutritional values during storage in sliced carrots better than chlorine. Colour and texture objective measurements did not show differences between treatments for Iceberg lettuce; however there were differences in colour in sliced carrots, showing greater change in colour values in samples treated with chlorine. Calcium lactate washing treatments prevented the bleaching effect on sa...

  10. Reaction products of chlorine dioxide.

    OpenAIRE

    Stevens, A A

    1982-01-01

    Inspection of the available literature reveals that a detailed investigation of the aqueous organic chemistry of chlorine dioxide and systematic identification of products formed during water disinfection has not been considered. This must be done before an informed assessment can be made of the relative safety of using chlorine dioxide as a disinfectant alternative to chlorine. Although trihalomethanes are generally not formed by the action of chlorine dioxide, the products of chlorine dioxi...

  11. P物质对大鼠结肠平滑肌细胞钾钙电流的影响%Effect of substance P on the potassium and calcium currents of colonic smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    唐勤彩; 罗和生; 全晓静; 樊菡; 余光

    2015-01-01

    Objective To investigate the effect of substance P(SP) on the spontaneous contractile activity of smooth muscle cells,the large-conductance calcium-activated potassium channel currents (IBKCa) and the L-type calcium channel currents (ICaL) in rat smooth muscle cells of the proximal colon.Methods A total of 24 healthy male Wista rats were used in this test.The change of smooth muscle strips spontaneous contraction of rat proximal colon after adding SP was recorded by a physiological signal stystem (RM6240).The IBKCa and ICaL were measured via the whole cell patch-clamp technique.Results The longitudinal muscle contraction was obviously increased concentration-dependently after adding different concentrations of SP (10-7-10-6 mol/L),so as the circular muscle while adding SP(10-8-10-6 mol/L) (all P < 0.05).Compared with the control group,IBKCa was decreased after adding SP(10-6mol/L).Under the stimulating voltage of 60 mY,the IBKCa current density was (11.71 ± 1.65) pA/pF,which was significantly lower compared with the control group (14.42 ± 2.89) pA/pF (P < 0.05).The ICaL was apparently increased.Under the stimulating voltage of 0 mY,the ICaL currents density was (-5.04 ± 0.67) pA/pF,compared with the control group (-4.25 ± 0.46) pA/pF,which was significantly increased (P < 0.01).Conclusions SP can promote the spontaneous contractile activity of colon smooth muscle of rats in vitro.And SP decrease IBKCa representatively while apparently increase ICaL.That is probably one of the mechanism SP regulate the gastrointestinal motility.%目的 研究P物质(SP)对大鼠近端结肠平滑肌细胞大电导钙激活钾通道电流(IBKCa)和L型钙通道电流(ICaL)的影响,探讨其促结肠动力的作用机制.方法 选取健康雄性Wistar大鼠24只,采用RM6240生理信号采集处理系统记录SP对大鼠近端结肠平滑肌肌条收缩的影响;采用全细胞膜片钳技术检测SP对近端结肠平滑肌细胞IBKCa和ICaL的影响.结果 10-7~10-6 mol

  12. Penicillin V Potassium Oral

    Science.gov (United States)

    Penicillin V potassium is an antibiotic used to treat certain infections caused by bacteria such as pneumonia, ... Penicillin V potassium comes as a tablet and liquid to take by mouth. It is usually taken ...

  13. Potassium carbonate poisoning

    Science.gov (United States)

    Potassium carbonate is a white powder used to make soap, glass, and other items. This article discusses poisoning from swallowing or breathing in potassium carbonate. This article is for information only. Do ...

  14. Chlorine trifluoride (1963)

    International Nuclear Information System (INIS)

    This monograph on chlorine trifluoride may be considered as a working tool useful in gaseous diffusion research. It consists of data gathered from the literature and includes furthermore a certain amount of original data. This monograph groups together the physical, chemical and physiological properties of chlorine trifluoride, as well as the preparation and analytical methods. It has been thought wise to add some technological information, and the safety regulations governing its use. (authors)

  15. Zirconia concentrate chlorination

    International Nuclear Information System (INIS)

    Chlorination experiments were conducted in order to study the kinetics of gasification of the zirconium oxide present in the zirconia concentrate. The variables studied are temperature (1173 to 1373 K), percentage of reducing agent (12 to 36%) and porosity (22 to 30%). The results indicated a greater influence of temperature and percentage of reducing agent as well as allowed the conclusion that a balance between the levels of these variables is an important factor in the appropriate chlorination conditions. (author)

  16. KV7 potassium channels

    DEFF Research Database (Denmark)

    Stott, Jennifer B; Jepps, Thomas Andrew; Greenwood, Iain A

    2014-01-01

    Potassium channels are key regulators of smooth muscle tone, with increases in activity resulting in hyperpolarisation of the cell membrane, which acts to oppose vasoconstriction. Several potassium channels exist within smooth muscle, but the KV7 family of voltage-gated potassium channels have been...

  17. Sodium and potassium

    International Nuclear Information System (INIS)

    Present article is devoted to sodium and potassium content in fluoride. In order to obtain the comprehensive view on sodium and potassium distribution in fluorite 892 mono mineral samples of various geologic deposits and ores of Kazakhstan, Uzbekistan, Tajikistan were analyzed. The content of sodium and potassium in fluorite of geologic deposits of various mineralogical and genetic type was defined.

  18. Role of calcium conductance in firing behavior of retinal ganglion cells

    Institute of Scientific and Technical Information of China (English)

    Dan Wang; Qingli Qiao; Nan Xie

    2011-01-01

    Fohlmeister-Coleman-Miller model of retinal ganglion cells consists of five ion channels; these are sodium channels, calcium channels, and 3 types of potassium channels. An increasing number of studies have investigated sodium channels, voltage-gated potassium channels, and delayed rectifier potassium channels. However, little is known about calcium channels, and in particular the dynamics and computational models of calcium ions. Retinal prostheses have been designed to assist with sight recovery for the blind, and in the present study, the effects of calcium ions in retinal ganglion cell models were analyzed with regard to calcium channel potential and calcium-activated potassium potential. Using MATLAB software, calcium conductance and calcium current from the Fohlmeister-Coleman-Miller model, under clamped voltages, were numerically computed using backward Euler methods. Subsequently, the Fohlmeister-Coleman-Miller model was simulated with the absence of calcium-current (lc,) or calcium-activated potassium current (IK, ca). The model was also analyzed according to the phase plane method.The relationship curve between peak calcium current and clamped potentials revealed an inverted bell shape, and the calcium-activated potassium current increased the frequency of firing and the peak of membrane potential. Results suggested that calcium ion concentrations play an important role in controlling the peak and the magnitude of peak membrane voltage in retinal ganglion cells.

  19. Calcium microdomains near R-type calcium channels control the induction of presynaptic LTP at parallel fiber to Purkinje cell synapses

    OpenAIRE

    Myoga, Michael H.; Regehr, Wade G.

    2011-01-01

    R-type calcium channels in postsynaptic spines signal through functional calcium microdomains to regulate a calcium-calmodulin sensitive potassium channel that in turn regulates postsynaptic hippocampal LTP. Here we ask whether R-type calcium channels in presynaptic terminals also signal through calcium microdomains to control presynaptic LTP. We focus on presynaptic LTP at parallel fiber to Purkinje cell synapses in the cerebellum (PF-LTP), which is mediated by calcium/calmodulin-stimulated ...

  20. Calcium - urine

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003603.htm Calcium - urine To use the sharing features on this ... enable JavaScript. This test measures the amount of calcium in urine. All cells need calcium in order ...

  1. Calcium supplements

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007477.htm Calcium supplements To use the sharing features on this page, please enable JavaScript. WHO SHOULD TAKE CALCIUM SUPPLEMENTS? Calcium is an important mineral for the ...

  2. Calcium Oscillations

    OpenAIRE

    Dupont, Geneviève; Combettes, Laurent; Bird, Gary S.; Putney, James W.

    2011-01-01

    Calcium signaling results from a complex interplay between activation and inactivation of intracellular and extracellular calcium permeable channels. This complexity is obvious from the pattern of calcium signals observed with modest, physiological concentrations of calcium-mobilizing agonists, which typically present as sequential regenerative discharges of stored calcium, a process referred to as calcium oscillations. In this review, we discuss recent advances in understanding the underlyin...

  3. Nutrição de mudas de açaizeiro sob relações cálcio:potássio:sódio em solução nutritiva Nutrition of açai seedlings (Euterpe oleracea Mart. under different ratios of calcium:potassium: sodium in nutrient solution

    Directory of Open Access Journals (Sweden)

    Humberto Umbelino de Sousa

    2004-02-01

    Full Text Available Objetivando-se estudar diferentes relações entre os cátions cálcio, potássio e sódio na produção de matéria seca e acúmulo de macronutrientes em mudas de açaizeiro (Euterpe oleracea Mart., realizou-se um experimento em casa-de-vegetação no Departamento de Ciência do Solo da UFLA. Utilizou-se o delineamento estatístico em blocos casualisados com nove tratamentos em quatro repetições. Os tratamentos foram constituídos por nove relações cálcio: potássio: sódio (4:2:1, 3:3:1, 2:4:1, 1:5:1, 5:1:1, 4:1:2, 6:0:1; 0:6:1, e 4:2:0 em solução nutritiva. A unidade experimental constituiu-se de um vaso com capacidade para três litros de solução, contendo duas plantas. Avaliaram-se as seguintes características: produção de matéria seca e o acúmulo dos macronutrientes fósforo, cálcio, potássio, magnésio e enxofre na matéria seca da planta. A relação cálcio:potássio:sódio influenciou todas as características avaliadas; as soluções contendo cálcio, potássio e sódio nas relações 4:2:1 e 3:3:1 resultaram no desenvolvimento de mudas com maior produção de matéria seca e maior acúmulo de nutrientes.Aiming to evaluate the effects of different ratios of calcium, potassium and sodium cations on the mineral nutrition of açai seedlings (Euterpe oleracea Mart., a greenhouse experiment was carried out in the Soil Science Department at the Federal University of Lavras-UFLA. The randomized block design, with nine treatments and four replications, was used. The treatments were nine ratios of calcium, potassium and sodium (4:2:1, 3:3:1, 2:4:1, 1:5:1, 5:1:1, 4:1:2, 6:0:1; 0:6:1, e 4:2:0 in the nutrient solution. The experimental unit was a plastic pot with three liters of solution, containing two plants. The total dry matter and nutrient accumulation were evaluated. The relationship calcium:potassium:sodium influenced all the appraised characteristics, and the solutions containing calcium, potassium and sodium in the ratios

  4. Chemical characterization of a potassium hydroxyapatite prepared by soaking in potassium chloride and carbonate solutions.

    Science.gov (United States)

    Nordström, E G; Karlsson, K H

    1992-01-01

    A potassium-doped synthetic apatite was prepared by soaking hydroxyapatite in potassium carbonate and potassium chloride solutions. The hydroxyapatite was prepared by firing slip cast ceramic bodies in vacuum at 1100 degrees C. The conical ceramic samples and a crushed material of this were soaked in carbonate and chloride solutions for 2, 4, 6, and 8 weeks. Potassium, calcium, and phosphate were determined by direct current plasma emission spectroscopy. The carbonate content was determined by thermogravimetric analysis and chloride titrimetrically. After 2 weeks, one potassium ion substituted one calcium ion when soaked in a carbonate solution. When soaked in the chloride solution substitution occurred to the same extent. At phosphate sites the substitution of phosphate for carbonate occurred at one sixth of the sites after 2 weeks. Chloride incorporated one half of the OH-sites after 2 weeks. After 4 weeks about one chloride ion was found in the apatite, and after 6 weeks one and a half of the OH-sites were occupied by chloride ions. PMID:1483120

  5. Chlorine, Chloramine, Chlorine Dioxide, and Ozone Susceptibility of Mycobacterium avium

    OpenAIRE

    Taylor, Robert H.; Joseph O. Falkinham; Norton, Cheryl D.; LeChevallier, Mark W.

    2000-01-01

    Environmental and patient isolates of Mycobacterium avium were resistant to chlorine, monochloramine, chlorine dioxide, and ozone. For chlorine, the product of the disinfectant concentration (in parts per million) and the time (in minutes) to 99.9% inactivation for five M. avium strains ranged from 51 to 204. Chlorine susceptibility of cells was the same in washed cultures containing aggregates and in reduced aggregate fractions lacking aggregates. Cells of the more slowly growing strains wer...

  6. Thermodynamic analysis of the selective chlorination of electric arc furnace dust

    International Nuclear Information System (INIS)

    The remelting of automobile scrap in an electric arc furnace (EAF) results in the production of a dust, which contains high concentrations of the oxides of zinc, iron, calcium and other metals. Typically, the lead and zinc are of commercial value, while the other metals are not worth recovering. At the present time, EAF dusts are treated in high temperature Waelz rotary kiln-type processes, where the lead and zinc oxides are selectively reduced and simultaneously reoxidized and a crude zinc oxide is produced. Another alternative processing route is selective chlorination, in which the non-ferrous metals are preferentially chlorinated to their gaseous chlorides and in this manner separated from the iron. In the present research, a detailed thermodynamic analysis of this chlorination process has been performed and the following factors were investigated; temperature, amount of chlorine, lime content, silica content, presence of an inert gas and the oxygen potential. High lead and zinc recoveries as gaseous chlorides could be achieved but some of the iron oxide was also chlorinated. Additionally, the calcium oxide in the dust consumes chlorine, but this can be minimized by adding silica, which results in the formation of stable calcium silicates. The optimum conditions were determined for a typical dust composition. The selectivities achieved with chlorination were lower than those for reduction, as reported in the literature, but there are other advantages such as the potential recovery of copper.

  7. Potassium and Health123

    OpenAIRE

    Weaver, Connie M.

    2013-01-01

    Potassium was identified as a shortfall nutrient by the Dietary Guidelines for Americans 2010 Advisory Committee. The committee concluded that there was a moderate body of evidence of the association between potassium intake and blood pressure reduction in adults, which in turn influences the risk of stroke and coronary heart disease. Evidence is also accumulating of the protective effect of adequate dietary potassium on age-related bone loss and reduction of kidney stones. These benefits dep...

  8. Localization and pharmacological characterization of voltage dependent calcium channels in cultured neocortical neurons

    DEFF Research Database (Denmark)

    Timmermann, D B; Lund, T M; Belhage, B;

    2001-01-01

    in cytosolic calcium concentration. The results of this investigation demonstrate that pharmacologically distinct types of voltage dependent calcium channels are differentially localized in cell bodies, neurites and nerve terminals of mouse cortical neurons but that the Q-type calcium channel appears......The physiological significance and subcellular distribution of voltage dependent calcium channels was defined using calcium channel blockers to inhibit potassium induced rises in cytosolic calcium concentration in cultured mouse neocortical neurons. The cytosolic calcium concentration was measured...... using the fluorescent calcium chelator fura-2. The types of calcium channels present at the synaptic terminal were determined by the inhibitory action of calcium channel blockers on potassium-induced [3H]GABA release in the same cell preparation. L-, N-, P-, Q- and R-/T-type voltage dependent calcium...

  9. Potassium food supplement

    Science.gov (United States)

    Bourland, C. T.; Huber, C. S.; Rambaut, C.; Heidelbaugh, N. D.

    1973-01-01

    Potassium gluconate is considered best supplementary source for potassium. Gluconate consistently received highest taste rating and was indistinguishable from nonsupplemented samples. No unfavorable side effects were found during use, and none are reported in literature. Gluconate is normal intermediary metabolite that is readily adsorbed and produces no evidence of gastrointestinal ulcerations.

  10. Penicillin V Potassium Oral

    Science.gov (United States)

    V-Cillin K® ... Penicillin V potassium is an antibiotic used to treat certain infections caused by bacteria such as pneumonia, scarlet fever, ... Penicillin V potassium comes as a tablet and liquid to take by mouth. It is usually taken every 6 ...

  11. Calcium Forms,Subcelluar Distribution and Ultrastructure of Pulp Cells as Influenced by Calcium Deficiency in Apple (Malus pumila) Fruits

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-hui; ZHOU Wei

    2004-01-01

    Calcium in Red Fuji and Starkrimson apples during storage were fractionated by sequent extracting. Localization and distribution of calcium and influence of calcium nutrition on cell ultrastructure were observed by transmission electron microscopy combined with in situ precipitation of calcium with an improved method of potassium pyroantimonate technique. Results indicated that spraying calcium solution on surface of young fruits increased contents of calcium in all forms. During storage, contents of soluble calcium and pectic calcium declined and thosein calcium phosphate, calcium oxalate and calcium silicate increased. Calcium contents of Red Fuji in all forms were higher than those of Starkrimson, indicating that calcium accumulating capability of Red Fuji fruits preceded that of Starkrimson. Under transmission electron microscopy, calcium antimonite precipitates (CaAP) was mainly distributed in cell wall, tonoplast, nuclear membrane and nucleoplasm,much more CaAP deposited in vacuole. Calcium deficiency during storage leads to decrease of CaAP in locations mentioned above, disappearance of compartmentation, and entrance of CaAP to cytoplasm. Transformation from soluble calcium and pectic calcium to calcium phosphate,oxalate and damages of biomembranes structuraly and functionally resulted from calcium deficiency during storage were the crucial causation of physiological disorder.

  12. Chlorination of pyrene in soil components with sodium chloride under xenon irradiation

    International Nuclear Information System (INIS)

    It was previously reported that chlorinated pyrenes (1-chloropyrene and dichloropyrene) were produced from pyrene in soil under sunlight irradiation. It was suggested that pyrene reacted with chlorine ion under sunlight. In this work, the formation of chlorinated pyrenes is investigated on 9 metallic oxides as soil components with pyrene and sodium chloride under xenon lamp irradiation. The chlorinated pyrenes as the reaction products were extracted with benzene:ethanol (4:1), and analyzed by GC/MS (SIM). The chlorinated pyrenes were produced in high amounts on 5 metallic oxides [silicon dioxides (quartz, silicic anhydride and silica gel forms) and titanium dioxides (rutile and anatase forms)] and in small amounts in 3 sorts of metallic oxides (aluminium oxide, magnesium oxide and ferric oxide), whereas they were not produced on calcium oxide. It was found that the yields of chlorinated pyrenes depended on the amounts of pyrene and chlorine ions in metallic oxides. In silicon dioxides, the yields of chlorinated pyrenes increased as the irradiation time was extended. In the titanium dioxides, the yields of chlorinated pyrenes had a peak at 0.5 – 1 hours irradiation of xenon lamp, and decreased as the irradiation time elapsed. (author)

  13. 40 CFR 721.2076 - D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium...

    Science.gov (United States)

    2010-07-01

    ...-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium salt. 721.2076 Section 721...-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium magnesium potassium sodium... identified as D-Glucuronic acid, polymer with 6-deoxy-L-mannose and D-glucose, acetate, calcium...

  14. Chlorination of zirconyte concentrate

    International Nuclear Information System (INIS)

    Chlorination experiments with zirconyte concentrate were carried out in order to study the effects of temperature, percentage of reducing agent and porosity on the gasification of ZrO2 for 10 and 20 minutes of reaction. Factorial analysis was applied and the results indicated that temperature and percentage of reducing agent were the two only variables effecting the ZrO2 gasification. (author)

  15. Chlorine Dioxide-Iodide-Methyl Acetoacetate Oscillation Reaction Investigated by UV-Vis and Online FTIR Spectrophotometric Method

    OpenAIRE

    Laishun Shi; Xiaomei Wang; Na Li; Jie Liu; Chunying Yan

    2012-01-01

    In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide-iodide ion-methyl acetoacetate reaction system, a series of experiments were done by using UV-Vis and online FTIR spectrophotometric method. The initial concentrations of methyl acetoacetate, chlorine dioxide, potassium iodide, and sulfuric acid and the pH value have great influence on the oscillation observed at wavelength of 289 nm. There is a preoscillatory or induction period, and the amplitude and...

  16. Potassium channels and vascular reactivity in genetically hypertensive rats.

    Science.gov (United States)

    Furspan, P B; Webb, R C

    1990-06-01

    In hypertension, membrane potassium permeability and vascular reactivity are increased. This study characterizes a potassium-selective channel and contractions to barium, a potassium channel inhibitor, in vascular smooth muscle (tail artery) from spontaneously hypertensive stroke-prone rats (SHRSP) and normotensive Wistar-Kyoto (WKY) rats. Smooth muscle cells were isolated by enzymatic digestion, and potassium channel activity was characterized by using patch-clamp technique (inside-out configuration). Isometric contractile activity was evaluated in helically cut arterial strips by using standard muscle bath methodology. In membrane patches, a voltage-gated, calcium-insensitive, potassium-selective channel of large conductance (200 picosiemens) was observed. The channel did not conduct sodium or rubidium. Barium (10(-6) to 10(-4) M) produced a dose-dependent blockade of channel activity. These channel characteristics did not differ in SHRSP and WKY rat cells. After treatment with 35 mM KCl, barium (10(-5) to 10(-3) M) caused greater contractions in SHRSP arteries compared with arteries in WKY rats. The contractions to barium were markedly attenuated in calcium-free solution, and nifedipine and verapamil abolished contractions induced by barium in depolarizing solution. We conclude that increased vascular reactivity to barium in SHRSP arteries is not due to an alteration in the biophysical properties of the potassium channel studied. PMID:2351424

  17. K/C age determination in potassium fieldspars

    International Nuclear Information System (INIS)

    A method for the potassium/calcium age determination of geological material is described. The calcium isotope intensities are measured with a mass spectrometer by the thermal ionization technique. The 42Ca/44Ca isotope ratio is used as an internal standard to correct the measured 40Ca/42Ca ratio for mass discrimination. The radiogenic 40Ca portion and the calcium content of the minerals are determined in different analytical steps. Two feldspars are dated with relative standard deviations of 1.8 and 4 per cent, respectively. (orig.)

  18. Reactions of aqueous chlorine and chlorine dioxide with model food compounds.

    OpenAIRE

    Fukayama, M Y; Tan, H; Wheeler, W B; Wei, C I

    1986-01-01

    Chlorine and chlorine dioxide (ClO2), common disinfecting and bleaching chemicals used in the food industry, are potent oxidizing and chlorinating agents. Unfortunately, little is known about the nature of the reactions of chlorine with organic food constituents. This presentation reviews published information concerning the reactions of chlorine gas (Cl2[g]), aqueous chlorine, and ClO2 with model food compounds, the fate of chlorine during the chlorination of specific food products, and the ...

  19. The chlorination of cooling water

    International Nuclear Information System (INIS)

    After reviewing the means of fighting biological pollution of cooling water circuits in nuclear power stations, the authors describe the chlorination treatment methods used by EDF. This deals with the massive shock chlorination of the cooling towers and the continuous low-level chlorination of coastal nuclear power stations. In both areas, the Research and Development Board of EDF has carried out and encouraged research with the aim of improving circuit protection, while still protecting the aquatic eco-system against damage that might be caused by waste chlorinated water

  20. 氮素形态和氮水平对烟草氮、磷、钾、氯积累分配的影响%Effect of Nitrogen Form and Concentration on Distribution of Nitrogen, Phosphorus, Potassium and Chlorine in Different Organs of Tobacco

    Institute of Scientific and Technical Information of China (English)

    杨秋云; 王国峰; 黄向东; 介晓磊; 刘世亮; 化党领

    2011-01-01

    为了解不同氮素形态和氮水平对烟草吸收矿质元素的影响,开展了营养液栽培试验.结果表明:纯硝态氮供应的叶片氮、磷含量随氮质量浓度增加而降低;有铵参与供氮的叶片氮、磷含量随氮质量浓度的增加而增加;叶片钾含量随总氮供应变化的规律不同于氮、磷,其在铵硝比5∶5之前随氮质量浓度的增加而降低,在铵硝比达到7∶3之后随氮质量浓度增加而增加,以铵硝比0∶10并氮质量浓度35 mg/L时取得叶片最高钾含量(6.32%),在铵硝比10∶0并氮质量浓度为35 mg/L时取得最低钾含量(3.19%);叶片氯含量有随铵硝比增大而提高的趋势.随铵硝比增加,叶片氮、磷、钾、氯和茎中氮、磷、钾积累量降低,铵硝比相同时,随氮质量浓度增加,钾积累量增加,叶片钾积累量在铵硝比0∶ 10并氮质量浓度140 mg/L时取得最高积累量1543.57 mg/株;根氮、磷积累量在铵硝比7∶3及以下,随氮质量浓度增加而增加,根钾积累量随供氮改变没有明显变化规律.叶片中氮、磷、钾含量和积累量均高于茎、根中氮、磷、钾含量和积累量.研究认为:铵态氮有利于叶片磷、氯积累,不利于叶片钾积累;硝态氮有利于叶片钾积累,不利于叶片磷、氯积累,在较高氮质量浓度下不利于叶片氮积累.%For understanding the effect of two forms of nitrogen(N) and nitrogen concentration on absorption of main mineral elements by different organs in tobacco, outdoor hydroponics were carried out. The conclusions were as follows. In leafs, N and phosphorus(P) content increased with N concentration decreasing at only nitrate-N, and increased with both ammonium and nitrate supplement. The trend of potassium(K) content changing with N were different with N and P. The content of K decreased with N rising below the ratio of 5: 5.and achieved the highest content of6. 32% at 0: 10 of ammonium/nitrate ratio simultaneously at 35mg/L of N

  1. Effect of silica fume addition on the PGNAA measurement of chlorine in concrete.

    Science.gov (United States)

    Naqvi, A A; Maslehuddin, M; Garwan, M A; Nagadi, M M; Al-Amoudi, O S B; Raashid, M; Khateeb-ur-Rehman

    2010-03-01

    Pozzolanic materials, such as fly ash (FA), silica fume (SF), and blast furnace slag (BFS) are added to Portland cement in concrete to prevent reinforcement steel corrosion in concrete. Further preventive measure against reinforcement steel corrosion require monitoring of chloride salts concentration in concrete using non-destructive techniques, such as the prompt gamma-ray neutron activation analysis (PGNAA) technique. Due to interferences between gamma-rays from chlorine and calcium in PGNAA technique, detection limit of chlorine in concrete strongly depends upon calcium concentration in concrete. SF mainly contains silica and its addition to cement concrete reduces overall concentration of calcium in concrete. This may result in an improvement in detection limit of chlorine in SF-based concrete in PGNAA studies. Particularly for chlorine detection using 6.11 and 6.62 MeV prompt gamma-rays that strongly interfere with 6.42 MeV prompt gamma-rays from calcium. In this study, SF was added to Portland cement to prevent concrete reinforcement steel from corrosion. The chlorine concentration in SF cement concrete specimens containing 0.2-3.0 wt% chlorine was measured through yield of 1.16, 1.95, 6.11, 6.62, 7.41, 7.79, and 8.58 MeV chlorine gamma-rays using PGNAA technique. An excellent agreement was noted between the experimental yield of the prompt gamma-rays and the gamma-ray yield calculated through the Monte Carlo simulations. Further the minimum detectable concentration (MDC) of chlorine in SF cement concrete was calculated and compared with the MDC values of chlorine in plain concrete and concrete mixed with fly ash cement. The MDC of chlorine in SF-based concrete through 6.11 MeV, and 6.62 MeV chlorine gamma-rays was found to be improved as compared to those in plain concrete and concrete mixed with fly ash cement. PMID:20042342

  2. Synthesis of calcium hydroxyapatite from calcium carbonate and different orthophosphate sources: A comparative study

    International Nuclear Information System (INIS)

    Highlights: ► Calcium hydroxyapatite was synthesized from CaCO3 and four orthophosphates. ► Only H3PO4 led to the complete precipitation of orthophosphate species. ► H3PO4 was also the most efficient for calcium dissolution. ► Reaction pathway was dissolution-precipitation accompanied by agglomeration step. - Abstract: The synthesis of calcium hydroxyapatite (Ca-HA) starting from calcium carbonate and different orthophosphate sources, including orthophosphoric acid, potassium, sodium and ammonium dihydrogen orthophosphates, was investigated under ambient conditions. The reaction started with calcium carbonate dissolution in an acid medium, followed by rapid precipitation of calcium cations with orthophosphate species to form calcium phosphate based particles which were in the size range of 0.4–1 μm. These particles then agglomerated into much larger ones, up to 350 μm in diameter (aggregates). These aggregates possessed an unstable porous structure which was responsible for the porosity of the final products. The highest specific surface area and pore volume were obtained with potassium dihydrogen orthophosphate. On the other hand, orthophosphoric acid led to the highest dissolution of calcium carbonate and the complete precipitation of orthophosphate species. Under ambient conditions, calcium phosphate based solid products of low crystallinity were formed. Different intermediates were identified and a reaction pathway proposed.

  3. Intercomparison 9711. pH, conductivity, alkalinity, nitrate + nitrite, chloride, sulfate, calcium, magnesium, sodium, potassium, total aluminium, reactive and non-labile aluminium, dissolved organic carbon, and chemical oxygen demand

    Energy Technology Data Exchange (ETDEWEB)

    Hovind, Haavard

    1997-09-22

    The work described in this report was a part of an international cooperative programme for assessment and monitoring of acidification of rivers and lakes. Two sample sets were prepared for intercomparison, one for determination of the major ions, the other for determination of aluminium fractions and unspecified organic matter. The samples were sent to 50 laboratories and 47 laboratories from 22 countries submitted results. Good agreement was found for chloride, sulfate, calcium, magnesium, sodium and the unspecific organic compounds, dissolved organic carbon and chemical oxygen demand, more than 80% being evaluated as acceptable for these analytic variables. The results for nitrate + nitrite and aluminium species did not agree well, probably because different methods were used to determine the aluminium species. On the whole, 78% of the results were within the general target accuracy of plus or minus 20%. Laboratories with results outside this accuracy should improve their methods if they want to analyse low-concentration samples. To improve the compatibility of the analytical results for aluminium fractions, it seems necessary to normalize the analytical methods and determination techniques used for these determinations. A total error of plus minus 0.2 pH units seems to be a reasonable assessment of the accuracy for pH measurements when weakly acid or neutral water samples not in CO{sub 2} equilibrium are analyzed. 7 refs., 1 fig., 34 tabs.

  4. High Temperature Stability of Potassium Beta Alumina

    Science.gov (United States)

    Williams, R. M.; Kisor, A.; Ryan, M. A.

    1996-01-01

    None. From Objectives section: Evaluate the stability of potassium beta alumina under potassium AMTEC operating conditions. Evaluate the stability regime in which potassium beta alumina can be fabricated.

  5. HCl removal using cycled carbide slag from calcium looping cycles

    International Nuclear Information System (INIS)

    Highlights: • Cycled carbide slag from calcium looping cycles is used to remove HCl. • The optimum temperature for HCl removal of cycled carbide slag is 700 °C. • The presence of CO2 restrains HCl removal of cycled carbide slag. • CO2 capture conditions have important effects on HCl removal of cycled carbide slag. • HCl removal capacity of carbide slag drops with cycle number rising from 1 to 50. - Abstract: The carbide slag is an industrial waste from chlor-alkali plants, which can be used to capture CO2 in the calcium looping cycles, i.e. carbonation/calcination cycles. In this work, the cycled carbide slag from the calcium looping cycles for CO2 capture was proposed to remove HCl in the flue gas from the biomass-fired and RDFs-fired boilers. The effects of chlorination temperature, HCl concentration, particle size, presence of CO2, presence of O2, cycle number and CO2 capture conditions in calcium looping cycles on the HCl removal behavior of the carbide slag experienced carbonation/calcination cycles were investigated in a triple fixed-bed reactor. The chlorination product of the cycled carbide slag from the calcium looping after absorbing HCl is not CaCl2 but CaClOH. The optimum temperature for HCl removal of the cycled carbide slag from the carbonation/calcination cycles is 700 °C. The chlorination conversion of the cycled carbide slag increases with increasing the HCl concentration. The cycled carbide slag with larger particle size exhibits a lower chlorination conversion. The presence of CO2 decreases the chlorination conversions of the cycled carbide slag and the presence of O2 has a trifling impact. The chlorination conversion of the carbide slag experienced 1 carbonation/calcination cycle is higher than that of the uncycled calcined sorbent. As the number of carbonation/calcination cycles increases from 1 to 50, the chlorination conversion of carbide slag drops gradually. The high calcination temperature and high CO2 concentration in the

  6. Outward potassium current oscillations in macrophage polykaryons: extracellular calcium entry and calcium-induced calcium release

    Directory of Open Access Journals (Sweden)

    Saraiva R.M.

    1997-01-01

    Full Text Available Outward current oscillations associated with transient membrane hyperpolarizations were induced in murine macrophage polykaryons by membrane depolarization in the absence of external Na+. Oscillations corresponded to a cyclic activation of Ca2+-dependent K+ currents (IKCa probably correlated with variations in intracellular Ca2+ concentration. Addition of external Na+ (8 mM immediately abolished the outward current oscillations, suggesting that the absence of the cation is necessary not only for their induction but also for their maintenance. Oscillations were completely blocked by nisoldipine. Ruthenium red and ryanodine reduced the number of outward current cycles in each episode, whereas quercetin prolonged the hyperpolarization 2- to 15-fold. Neither low molecular weight heparin nor the absence of a Na+ gradient across the membrane had any influence on oscillations. The evidence suggests that Ca2+ entry through a pathway sensitive to Ca2+ channel blockers is elicited by membrane depolarization in Na+-free medium and is essential to initiate oscillations, which are also dependent on the cyclic release of Ca2+ from intracellular Ca2+-sensitive stores; Ca2+ ATPase acts by reducing intracellular Ca2+, thus allowing slow deactivation of IKCa. Evidence is presented that neither a Na+/Ca2+ antiporter nor Ca2+ release from IP3-sensitive Ca2+ stores participate directly in the mechanism of oscillation

  7. Na+ -K+ pump activity in rat peritoneal mast cells: inhibition by extracellular calcium

    DEFF Research Database (Denmark)

    Knudsen, Torben; Johansen, Torben

    1989-01-01

    1. Pure populations of rat peritoneal mast cells were used to study cellular potassium uptake. The radioactive potassium analogue, 86rubidium, was used as a tracer for potassium for measurements of the activity of the cellular potassium uptake process. 2. The ouabain-sensitive and the ouabain...... nature of an enzyme, and it is mediated by the Na+ -K+ pump located in the plasma membrane. It is demonstrated that the activity of the Na+ -K+ pump mechanism is inhibited by low concentrations of extracellular calcium (0.1-1.2 mmol l-1). The possibility is discussed that calcium-deprivation may increase...

  8. Studies with solid chlorine chemical for chlorination of sea water systems

    International Nuclear Information System (INIS)

    Chlorination is one of the conventional methods to control biofouling of condenser cooling water systems using either river water, reservoir water or sea water. However, there are many safety concerns associated with handling, storage and application of gaseous chlorine. Studies were carried out with suitable alternative chlorine chemical compounds which do not involve majority of these concerns but meet the functional requirement of gas chlorine. Trichloroisocyanuric Acid (TCCA) is one of the suitable alternatives to Gas chlorine. TCCA is a chlorine stabilized compound, stabilized with Cyanuric acid, thus similar to Gas Chlorine in its functions except that it is available in solid form. Release of chlorine is a gradual process in TCCA unlike Gaseous chlorine. Field studies with TCCA indicated gradual and near uniform release rate of chlorine, for longer duration with the requisite free residual chlorine levels (FRC). Thus, use of TCCA could be considered as a suitable alternative for gas chlorine for regular chlorination requirements. (author)

  9. Radiochemical analysis of chlorine-36

    International Nuclear Information System (INIS)

    The aim of this paper is to propose a radiochemical separation method of chlorine-36 from other beta-gamma emitters based on an oxidation technique where chlorine is trapped by NaOH. Chlorine-36 beta emissions are measured by liquid scintillation counting by the dual label technique in order to avoid the contamination produced by carbon-14 which is also trapped by NaOH and it is the main contaminant present in graphite samples. The sensitivity of this radiochemical method is high enough to achieve the needed thresholds for the radiological characterization of the radioactive materials in which this method can be applied

  10. Comparison of the effects of nitric oxide and hydrogen sulfide on calcium and potassium currents of rat colonic smooth muscle%一氧化氮和硫化氢对大鼠结肠平滑肌钙钾电流影响的比较

    Institute of Scientific and Technical Information of China (English)

    全晓静; 罗和生; 陈炜; 崔凝; 夏虹; 余光

    2015-01-01

    目的 比较一氧化氮(NO)与硫化氢(H2S)对大鼠结肠平滑肌细胞钙钾电流的影响,并探讨其抑制结肠动力的机制.方法 采用酶消化法分离近端结肠平滑肌细胞,运用全细胞膜片钳技术记录NO供体硝普钠(SNP,200 μmol/L)和H2S供体硫氢化钠(NaHS,300 μmol/L)对平滑肌细胞L型钙通道电流(ICa.L)和大电导钙激活钾电流(IBKCa)的影响.结果 膜电位0 mV处,SNP和NaHS均显著抑制ICaL峰值,SNP使峰电流密度由[(-3.76±0.66)pA/pF]降低至[(-2.67±0.42)pA/pF](P<0.01);NaHS使峰电流密度由[(-4.13 ±0.29)pA/pF]降低至[(-2.73 ±0.76)pA/pF](P<0.01);SNP明显抑制L型钙通道Ⅰ~Ⅴ曲线,但不影响其电压依赖特性;而NaHS使L型钙通道Ⅰ~Ⅴ曲线右移;SNP不影响L型钙通道的激活和失活特性;NaHS使L型钙通道的激活曲线和失活曲线均显著右移(P<0.05);SNP促进IBKCa,使电流密度由[(12.7±1.9) pA/pF]增加至[(14.7±2.1) pA/pF](P<0.05);NaHS抑制IBKCa,电流密度由[(15.5 ±2.4) pA/pF]降低至[(12.4±2.9) pA/pF] (P <0.05).结论 NO和H2S均抑制大鼠结肠平滑肌细胞(SMCs)收缩,但两者作用机制不同,NO通过抑制L型钙通道,激活BKCa通道抑制平滑肌收缩,而H2S则通过抑制L型钙通道抑制平滑肌收缩,但同时也抑制BKCa通道,其可能参与平滑肌钙稳态的调节.%Objective To investigate and compare the effects of nitric oxide (NO) and hydrogen sulfide (H2S) on calcium and potassium currents of rat colonic smooth muscle cells (SMCs).Methods The whole-cell patch-clamp technique was used to record the currents of L-type calcium channels and large conductance Ca2+-activated K + (BKCa) channels in SMCs isolated from male Wistar rat.Results Both the NO donor Sodium nitroferricyanide (Ⅲ) dihydrate (SNP, 200 μmol/L) and the H2S donor NaHS(300 μmol/L) inhibited L-type calcium current (ICa, L) at membrane potential of 0 mV, after application of SNP and NaHS, the current density significantly reduced from

  11. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  12. SYNTHESIS OF POTASSIUM FERRATE FOR USE IN TEXTILE WASTEWATER TREATMENT

    OpenAIRE

    F Vaezi; A. Mesdaghinia; H. Jamani

    1999-01-01

    Potassium ferrate has been used as a multi-purpose chemical in treatment of wastewaters. With the formula of K2Fe04 it has 3 excellent characters for water treatment, so by using it alone, it would be possible to confine all reactivity, it is essential to prepare ferrate at the point of use. In this study, K2Fe04 was synthesized, then it has been employed for chlorine gas with an alkaline solution of ferric chloride, then it has been employed for textile wastewater treatment. Textile is one o...

  13. Doses de potássio e cálcio no crescimento da planta, na produção e na qualidade de frutas do morangueiro em cultivo sem solo Potassium and calcium doses on plant growth, fruit yield and quality of strawberries in soilless cultivation

    Directory of Open Access Journals (Sweden)

    Jerônimo Luiz Andriolo

    2010-02-01

    Full Text Available Com o objetivo de avaliar o efeito de doses de potássio fornecido pela fertirrigação e de cálcio na parte aérea sobre o crescimento da planta, a produção e a qualidade de frutas do morangueiro em cultivo sem solo, plantas de morangueiro foram cultivadas com solução nutritiva contendo 9 (T1, 6 (T2, testemunha e 4,28mmol L-1 (T3 de K+ e com a solução testemunha (T2 suplementada uma vez por semana por pulverizações foliares de cálcio nas concentrações de 2,5 (T4 e 5g L-1 de CaCl2 (T5. O crescimento da planta foi reduzido no tratamento com a concentração de potássio mais elevada (T1, e o maior IAF foi obtido na dose mais elevada de CaCl2 (T5. A maior produção de frutas foi obtida em T2 e T3, a acidez (AT foi maior em T1, enquanto o teor de sólidos solúveis (SST e a relação SST/AT não diferiram significativamente entre os tratamentos. Concluiu-se que o aumento da concentração de potássio na solução nutritiva diminui o crescimento, a produção e a qualidade das frutas de morango e que a aplicação de cálcio na parte aérea das plantas por meio do CaCl2 reduz a produção de frutas.In order to evaluate the effect of potassium doses supplied by fertigation and of calcium by foliar spray on plant growth, fruit yield and quality of soilless grown strawberries, plants were supplied with nutrient solutions at K+ concentrations of 9 (T1; 6 (T2, control and 4.28mmol L-1 (T3 and with the control nutrient solution (T2 supplemented once a week by spraying CaCl2 on shoot at concentrations of 2.5 (T4 and 5g L- 1 (T5. Plant growth was lower in the higher potassium concentration (T1 and the highest LAI was recorded in the higher CaCl2 dose (T5. Fruit yield was higher in T2 and T3, the titratable acidity (TA was higher in T1, while total soluble solids (TSS and the ratio TTS/TA did not differ among treatments. It was concluded that high potasium concentration in the nutrient solution reduces plant growth, fruit yield and quality and

  14. Lack of direct evidence for a functional role of voltage-operated calcium channels in juxtaglomerular cells

    OpenAIRE

    Kurtz, Armin; Skott, O.; Chegini, S; Penner, R

    1990-01-01

    In this study we have examined the role of voltage-gated calcium channels in the regulation of calcium in juxtaglomerular cells. Using a combination of patch-clamp and single-cell calcium measurement we obtained evidence neither for voltage-operated calcium currents nor for changes of the intracellular calcium concentration upon acute depolarizations of the cell membrane. Increases of the extracellular concentration of potassium to 80 mmol/l depolarized the juxtaglomerular cells close to the ...

  15. Kinetic study of neodymium oxide chlorination with gaseous chlorine

    Energy Technology Data Exchange (ETDEWEB)

    Bosco, Marta V., E-mail: marta.bosco@cab.cnea.gov.ar [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Fouga, Gaston G. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Complejo Tecnologico Pilcaniyeu, Comision Nacional de Energia Atomica, Avenida Bustillo 9500, CP 8400 San Carlos de Bariloche (Argentina); Bohe, Ana E. [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Complejo Tecnologico Pilcaniyeu, Comision Nacional de Energia Atomica, Avenida Bustillo 9500, CP 8400 San Carlos de Bariloche (Argentina); Centro Regional Universitario Bariloche, Universidad Nacional del Comahue, CP 8400 San Carlos de Bariloche (Argentina)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer We analyze the kinetics of the neodymium oxide chlorination reactions. Black-Right-Pointing-Pointer For temperatures below 425 Degree-Sign C the system is under chemical control. Black-Right-Pointing-Pointer The formation of oxychloride progresses through a nucleation and growth mechanism. Black-Right-Pointing-Pointer A reaction order of 0.40 with respect to chlorine partial pressure was determined. Black-Right-Pointing-Pointer An activation energy of 161 {+-} 4 kJ mol{sup -1} was determined. - Abstract: The kinetics of the chlorination of neodymium oxide has been investigated by thermogravimetry between 312 Degree-Sign C and 475 Degree-Sign C, and for partial pressures of chlorine ranging from 10 kPa to 50 kPa. The starting temperature for the reaction of neodymium oxide with chlorine was determined to be about 250 Degree-Sign C, leading to neodymium oxychloride as product. The results showed that, for temperatures below 425 Degree-Sign C, the system is under chemical control and the formation of the oxychloride progresses through a nucleation and growth mechanism. The influence of chlorine mass transport through the bulk gas phase and through the boundary layer on the overall reaction rate was analyzed. In the absence of these two mass-transfer steps, a reaction order of 0.39 with respect to chlorine partial pressure, and an activation energy of 161 {+-} 4 kJ mol{sup -1} were determined. A complete rate equation has been successfully developed.

  16. Short-lived chlorine-36 in a Ca- and Al-rich inclusion from the Ningqiang carbonaceous chondrite

    OpenAIRE

    Lin, Yangting; Guan, Yunbin; Leshin, Laurie A.; Ouyang, Ziyuan; Wang, Daode

    2005-01-01

    Excesses of sulfur-36 in sodalite, a chlorine-rich mineral, in a calcium- and aluminum-rich inclusion from the Ningqiang carbonaceous chondrite linearly correlate with chorine/sulfur ratios, providing direct evidence for the presence of short-lived chlorine-36 (with a half-life of 0.3 million years) in the early solar system. The best inferred (36Cl/35Cl)o ratios of the sodalite are ≈5 × 10-6. Different from other short-lived radionuclides, chlorine-36 was introduced into the inclusion by sol...

  17. 剖宫产术前输注醋酸钠钾镁钙葡萄糖注射液对新生儿血气、血糖、乳酸及电解质的影响%Effects of Sodium Acetate Potassium Magnesium Calcium Glucose Injection on Neonatal Blood Gas, Blood Glucose, Lactate and Electrolytes before Cesarean Section

    Institute of Scientific and Technical Information of China (English)

    周晓筠; 黄军

    2014-01-01

    目的:观察剖宫产术前应用醋酸钠钾镁钙葡萄糖注射液对新生儿血气、血糖、乳酸及电解质的影响。方法选取2013年5月至12月需行剖宫产手术患者60例,依据分层随机分组法将患者分为治疗组及对照组,每组30例。对照组给予常规术前准备并进行剖宫产术;治疗组在对照组处理的基础上于术前加用醋酸钠钾镁钙葡萄糖注射液进行治疗。观察比较两组孕产妇手术前后血糖、游离脂肪酸、酮体变化以及用药不良反应情况,检测两组新生儿血气分析、电解质、血糖、乳酸及Apgar评分情况。结果术前两组孕产妇空腹血糖(FBG)、游离脂肪酸(NEFA)及酮体(KB)比较,差异无统计学意义( P>0.05)。术后治疗组孕产妇FBG为(6.75±1.71)mmol/L,明显高于对照组的(5.86±1.62)mmol/L,孕产妇 NEFA 为(0.57±0.18)mmol/L,KB 为(0.14±0.06)mmol/L,均分别低于对照组的(0.71±0.26)mmol/L和(0.19±0.09)mmol/L( P0.05)。结论剖宫产术前应用醋酸钠钾镁钙葡萄糖注射液,可显著改善孕产妇能量物质代谢情况及新生儿血气、电解质状况,并可提高新生儿Apgar评分。%Objective To observe the effect of Sodium Acetate Potassium Magnesium Calcium Glucose Injection on neonatal blood gas, blood glucose, lactate and electrolytes before cesarean section. Methods 60 pregnant woman requiring cesarean section in our hospital from May to December 2013 were divided into the treatment group and the control group according to the stratified randomized method, 30 cases in each group. The control group was given the routine preoperative preparation and performed cesarean section;while the treatment group was added with Sodium Acetate Potassium Magnesium Calcium Glucose Injection before operation on the basis of the control group treatment;the changes of blood glucose, free fatty acids, ketone bodies ( KB ) and adverse drug reactions

  18. Effect of ouabain, digoxin and digitoxigenin on potassium uptake and histamine release from rat peritoneal mast cells

    DEFF Research Database (Denmark)

    Knudsen, T; Ferjan, I; Johansen, Torben

    Rat peritoneal mast cells were used to study the effects of digitalis glycosides on potassium uptake and histamine release induced by compound 48/80, substance P and egg-albumin (immunological release). In the absence of calcium all glycosides inhibited potassium uptake. Ouabain and digoxin...... enhanced the histamine release while digitoxigenin either had no effect or was slightly inhibitory. In the presence of calcium, the glycosides only affected potassium uptake and histamine release slightly. In the presence of lithium or lanthanum the enhancement of the histamine release was counteracted....... Hydrophilic digitalis glycosides seem to enhance histamine release secondary to an increase in intracellular sodium. Lipophilic glycosides have no effect on the release....

  19. Calcium Carbonate

    Science.gov (United States)

    ... before being swallowed; do not swallow them whole. Drink a full glass of water after taking either the regular or chewable tablets or capsules. Some liquid forms of calcium carbonate must be shaken well before use.Do not ...

  20. Calcium Electroporation

    DEFF Research Database (Denmark)

    Frandsen, Stine Krog; Gibot, Laure; Madi, Moinecha;

    2015-01-01

    BACKGROUND: Calcium electroporation describes the use of high voltage electric pulses to introduce supraphysiological calcium concentrations into cells. This promising method is currently in clinical trial as an anti-cancer treatment. One very important issue is the relation between tumor cell kill...... efficacy-and normal cell sensitivity. METHODS: Using a 3D spheroid cell culture model we have tested the effect of calcium electroporation and electrochemotherapy using bleomycin on three different human cancer cell lines: a colorectal adenocarcinoma (HT29), a bladder transitional cell carcinoma (SW780......), and a breast adenocarcinoma (MDA-MB231), as well as on primary normal human dermal fibroblasts (HDF-n). RESULTS: The results showed a clear reduction in spheroid size in all three cancer cell spheroids three days after treatment with respectively calcium electroporation (p<0.0001) or...

  1. Calcium Calculator

    Science.gov (United States)

    ... Latvia - Lebanon - Libya - Lithuania - Luxembourg - Macedonia, Republic of - Malaysia - Malta - Mexico - Moldova - Morocco - Netherlands - New Zealand - Nigeria - ... and Statistics Popular content Calcium content of common foods What is Osteoporosis? The Board Introduction to Bone ...

  2. Analysis of potassium-40 in fertilizers containing potassium

    International Nuclear Information System (INIS)

    Remarking on gamma emitters, and making use of a pure germanium detector and a multichannel pulse-height-analyzer, analysis of natural radioactive nuclides in several fertilizers containing potassium was carried out. As the result of analyses on five samples, 228>Th, 226Ra, 235U and 40K were observed in all of the three compound-fertilizers, but no nuclide excepting 40Kwas observed in potassium chloride and potassium sulfate. 40K was fixed to be the most abundant nuclide, and the others were observed only in trace amounts. The activities of 40K in these fertilizers were nearly proportional to the contents of potassium in the samples. Contents of potassium in the fertilizers were obviously estimated from the values of 40K activities on the basis of natural abundance of 40K in potassium, and the contents estimated were in good agreement with the values determined by a chemical method

  3. Calcium pyrophosphate arthritis

    Science.gov (United States)

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

  4. Potassium toxicity at low serum potassium levels with refeeding syndrome.

    Science.gov (United States)

    Vemula, Praveen; Abela, Oliver G; Narisetty, Keerthy; Rhine, David; Abela, George S

    2015-01-01

    Refeeding syndrome is a life-threatening condition occurring in severely malnourished patients after initiating feeding. Severe hypophosphatemia with reduced adenosine triphosphate production has been implicated, but little data are available regarding electrolyte abnormalities. In this case, we report electrocardiographic changes consistent with hyperkalemia during potassium replacement after a serum level increase from 1.9 to 2.9 mEq/L. This was reversed by lowering serum potassium back to 2.0 mEq/L. In conclusion, the patient with prolonged malnutrition became adapted to low potassium levels and developed potassium toxicity with replacement. PMID:25456880

  5. Effects of Chlorine on Enterovirus RNA Degradation

    Science.gov (United States)

    The primary mechanism of disinfection of waterborne pathogens by chlorine has always been believed to be due to the alteration of proteins by free chlorine and subsequent disruption of their biological structure.

  6. Potassium-Related Periodic Paralysis

    OpenAIRE

    A Lesani; MH Moradi Nejad

    1995-01-01

    Potassium-related periodic paralysis may be associated with hypo, normo, or hyperkalemic disturbance of the Potassium level. Clinical features, laboratory findings and ECG as well as EMG changes are different in the 3 types of the disease. The treatment demands correction of the Potassium level of the blood serum. The disease is normally transferred as an autosomal dominant trait. In this article we present a 9-year old girl who suffered from hypokalemic paralysis since she was 4 years old.

  7. Recipe for potassium

    International Nuclear Information System (INIS)

    I investigate favorable conditions for producing potassium (K). Observations show [K/Fe] > 0 at low metallicities, while zero-metal supernova models show low [K/Fe] (e (from 0.51 to 0.60), the initial density ρmax (107, 108, and 109 [g/cm3]), and the e-fold time τ for the density (0.01, 0.1, and 1.0 [sec]). Among 90 models I have calculated, only 26 models show [K/Fe] > 0, and they all have ρmax = 109[g/cm3]. I discuss parameter dependence of [K/Fe].

  8. Positron scattering by potassium

    International Nuclear Information System (INIS)

    Coupled-state calculations in a K(4s, 4p, 5s, 5p, 3d) + Ps(1s, 2s, 2p, 3s, 3p, 3d) approximation are reported for positron scattering by ground-state potassium in the energy range 0.5-60.0 eV. Comparison is made with the earlier work of Hewitt et al (1993, 1994) in a K(4s, 4p, 5s, 5p) + Ps(1s, 2s, 2p) approximation. For the first time cross sections for positronium formation in n = 3 states are obtained. (author)

  9. Calcium entry into guinea-pig jejunum cells after calcium stores depletion.

    Science.gov (United States)

    Pacaud, P; Bolton, T B

    1991-01-01

    1) Membrane currents were recorded under voltage-clamp from cells using patch-clamp pipettes. Cells were dialysed with potassium-free caesium solution to block any Ca-activated K-current. The pipette solution contained Indo-1 and the ratio of the emissions from this dye at 480 and 405 nm was used to estimate the free calcium concentration in the cell. 2) Carbachol applied to the cell evoked at -50 mV an initial increase in the intracellular calcium concentration (Cai) followed by a smaller sustained rise (plateau); the changes in inward cationic current (ICarb) closely followed changes in Cai. Calcium entry blockers did not affect these responses. 3) The initial peak in Cai produced by carbachol was due to calcium store release: it was present in calcium-free solution, and unchanged at +50 mV, but it was abolished by prior application of caffeine (10 mM) to the cell or by inclusion of heparin (which blocks D-myoinositol 1,4,5-trisphosphate receptors) in the pipette. 4) The sustained rise (plateau) in Cai produced by carbachol was due to the entry of calcium into the cell down its electrochemical gradient as it was affected by changing the cell membrane potential or the calcium concentration in the bathing solution. As the sustained rise in Cai produced by caffeine had similar properties it was suggested that depletion of calcium stores can evoke an increased calcium entry into the cell through some pathway. PMID:1665265

  10. Potassium in milk and milk products

    International Nuclear Information System (INIS)

    The amount of potassium in imported processed milk was determined by gamma spectral analysis. The results show that the potassium content of diluted infant formula milk is closest to the reported mean concentration of potassium in human milk while other milk types have potassium values similar to the potassium content of cow milk. (Auth.). 2 figs., 5 refs

  11. Calcium and bones

    Science.gov (United States)

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

  12. Get Enough Calcium

    Science.gov (United States)

    ... Calcium Print This Topic En español Get Enough Calcium Browse Sections The Basics Overview Foods and Vitamins ... 2 of 4 sections Take Action! Take Action: Calcium Sources Protect your bones – get plenty of calcium ...

  13. Calcium carbonate overdose

    Science.gov (United States)

    Tums overdose; Calcium overdose ... Calcium carbonate can be dangerous in large amounts. ... Some products that contain calcium carbonate are certain: ... and mineral supplements Other products may also contain calcium ...

  14. Effects of ozone, chlorine dioxide, chlorine, and monochloramine on Cryptosporidium parvum oocyst viability.

    OpenAIRE

    Korich, D G; Mead, J R; Madore, M S; Sinclair, N. A.; Sterling, C R

    1990-01-01

    Purified Cryptosporidium parvum oocysts were exposed to ozone, chlorine dioxide, chlorine, and monochloramine. Excystation and mouse infectivity were comparatively evaluated to assess oocyst viability. Ozone and chlorine dioxide more effectively inactivated oocysts than chlorine and monochloramine did. Greater than 90% inactivation as measured by infectivity was achieved by treating oocysts with 1 ppm of ozone (1 mg/liter) for 5 min. Exposure to 1.3 ppm of chlorine dioxide yielded 90% inactiv...

  15. Consumo de fibra dietética, sodio, potasio y calcio y su relación con la presión arterial en hombres adultos normotensos Dietary fiber, energy, sodium, potassium and calcium intake and its relationship to blood pressure in normotensive male adults

    Directory of Open Access Journals (Sweden)

    Martha Nydia Ballesteros-Vásquez

    1998-05-01

    Full Text Available Objetivo. Evaluar el efecto del consumo de fibra dietética, energía, sodio, potasio y calcio sobre la presión arterial de un grupo de adultos normotensos, tomando en cuenta indicadores tales como la edad, el sexo, la actividad física y la obesidad. Material y métodos. Se evaluaron 38 sujetos del sexo masculino de 30 a 45 años de edad, normotensos, aparentemente sanos y residentes de la ciudad de Hermosillo, Sonora, México. Se midió la presión arterial y se realizó una evaluación dietética, antropométrica y de actividad física. Resultados. La dieta resultó ser alta en fibra y en grasa. El sodio estaba 56% por arriba de la recomendación en 87% de los casos y fue la variable que más efecto mostró sobre la presión diastólica. De los sujetos estudiados, 36.9% tenían sobrepeso y obesidad, y se encontró una asociación significativa entre el índice de masa corporal y la presión diastólica y sistólica. Conclusiones. Existe una asociación significativa entre la hipertensión arterial y el alto consumo de sodio, el sobrepeso y la obesidad en sujetos normotensos.Objective. To evaluate the effect of dietary fiber, energy, sodium, calcium and potassium intake on the blood pressure of a group of normotensive adults. Material and methods. Subjects were 38 healthy normotensive adult males aged 30-45 years, resident of Hermosillo, Sonora, Mexico. Blood pressure, diet, anthropometric data and physical activity were recorded. Results. Their diet was high in fiber and fat. Sodium intake was 56% above the recommended values in 87% of the subjects, and the variable with the highest correlation to diastolic blood pressure. Of the subjects, 36.9% were overweight and obese, and a significant statistic association was found between BMI and diastolic and systolic blood pressure. Conclusions. A significant relationship was found between hypertension and high consumption of sodium, overweight and obesity in healthy adult normotensive males.

  16. The calcium-activated potassium channels of turtle hair cells

    OpenAIRE

    1995-01-01

    A major factor determining the electrical resonant frequency of turtle cochlear hair cells is the time course of the Ca-activated K current (Art, J. J., and R. Fettiplace. 1987. Journal of Physiology. 385:207- 242). We have examined the notion that this time course is dictated by the K channel kinetics by recording single Ca-activated K channels in inside-out patches from isolated cells. A hair cell's resonant frequency was estimated from its known correlation with the dimensions of the hair ...

  17. Reducing chlorination of niobium pentoxide

    International Nuclear Information System (INIS)

    Studies of cylindric briquettes of Nb2O5 and carbon are presented. The effects of chlorine flow, dimension of the briquettes, porosity, percentage of the reducing agent in the mixture and temperature are analysed. The volatilization aspect of Nb2O5 by the briquettes and the structural transformations of the samples are described. (M.A.C.)

  18. Novel chlorinated derivatives of BODIPY

    OpenAIRE

    Garcia-Moreno, I.; Costela González, Ángel; Chiara, José Luis; Duran-Sampedro, G.; Ortiz, M. J.; Rodríguez Agarrabeitia, Antonio

    2012-01-01

    [EN] The invention relates to the use of novel dyes with a BODIPY structure, characterised in that they contain at least one chlorine atom bound to the carbons of the boradiazaindacene system, to the use thereof as laser dyes and fluorescent markers, and to a method for obtaining some of these compounds.

  19. Potassium channel antagonists and vascular reactivity in stroke-prone spontaneously hypertensive rats.

    Science.gov (United States)

    Kolias, T J; Chai, S; Webb, R C

    1993-06-01

    The goal of this study was to characterize differences in contractile responsiveness to several potassium channel antagonists in vascular smooth muscle from stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto normotensive rats (WKY). Helically-cut strips of carotid arteries (endothelium removed) from SHRSP and WKY were mounted in muscle baths for measurement of isometric force generation. Contractile responses to tetraethylammonium (10(-4) to 3 x 10(-2) mol/L) and barium (3 x 10(-5) mol/L), blockers of the voltage-dependent and large conductance, calcium activated potassium channels, were greater in carotid arteries from SHRSP than in those from WKY. In contrast, contractile responses to the voltage-dependent potassium channel blockers 3,4-diamino-pyridine (10(-6) to 3 x 10(-3) mol/L) and sparteine (10(-6) to 3 x 10(-2) mol/L) in arteries from SHRSP did not differ from WKY values. Carotid arteries from SHRSP and WKY did not contract to apamin (10(-9) to 10(-6) mol/L), an antagonist of the small conductance, calcium activated potassium channel. Furthermore, relaxation responses to diazoxide (3 x 10(-4) mol/L), an activator of the ATP-sensitive potassium channel, and subsequent contractions to the ATP-sensitive potassium channel blocker glyburide (10(-8) to 3 x 10(-6) mol/L) in arteries from SHRSP did not differ from WKY values. Carotid artery segments from SHRSP were more sensitive to the contractile effects of elevated potassium than those from WKY. We conclude that altered activity of the large conductance, calcium activated potassium channel may play a role in the increased responsiveness observed in arteries from SHRSP. PMID:8343237

  20. Neural synchronization via potassium signaling

    DEFF Research Database (Denmark)

    Postnov, Dmitry E; Ryazanova, Ludmila S; Mosekilde, Erik;

    2006-01-01

    Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...

  1. A new pH-sensitive rectifying potassium channel in mitochondria from the embryonic rat hippocampus.

    Science.gov (United States)

    Kajma, Anna; Szewczyk, Adam

    2012-10-01

    Patch-clamp single-channel studies on mitochondria isolated from embryonic rat hippocampus revealed the presence of two different potassium ion channels: a large-conductance (288±4pS) calcium-activated potassium channel and second potassium channel with outwardly rectifying activity under symmetric conditions (150/150mM KCl). At positive voltages, this channel displayed a conductance of 67.84pS and a strong voltage dependence at holding potentials from -80mV to +80mV. The open probability was higher at positive than at negative voltages. Patch-clamp studies at the mitoplast-attached mode showed that the channel was not sensitive to activators and inhibitors of mitochondrial potassium channels but was regulated by pH. Moreover, we demonstrated that the channel activity was not affected by the application of lidocaine, an inhibitor of two-pore domain potassium channels, or by tertiapin, an inhibitor of inwardly rectifying potassium channels. In summary, based on the single-channel recordings, we characterised for the first time mitochondrial pH-sensitive ion channel that is selective for cations, permeable to potassium ions, displays voltage sensitivity and does not correspond to any previously described potassium ion channels in the inner mitochondrial membrane. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012). PMID:22406520

  2. Cardiac potassium channel subtypes

    DEFF Research Database (Denmark)

    Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter

    2014-01-01

    About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...... drive the late repolarization of the ventricle with some redundancy, and in atria this repolarization reserve is supplemented by the fairly atrial-specific KV1.5, Kir3, KCa, and K2P channels. The role of the latter two subtypes in atria is currently being clarified, and several findings indicate that...... they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K(+) channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occurs in disease states such as atrial fibrillation or heart failure. The...

  3. Calcium paradox and calcium entry blockers

    NARCIS (Netherlands)

    Ruigrok, T.J.C.; Slade, A.M.; Nayler, W.G.; Meijler, F.L.

    1984-01-01

    Reperfusion of isolated hearts with calcium-containing solution after a short period of calcium-free perfusion results in irreversible cell damage (calcium paradox). This phenomenon is characterized by an excessive influx of calcium into the cells, the rapid onset of myocardial contracture, exhausti

  4. Calcium-Mediated Abiotic Stress Signaling in Roots.

    Science.gov (United States)

    Wilkins, Katie A; Matthus, Elsa; Swarbreck, Stéphanie M; Davies, Julia M

    2016-01-01

    Roots are subjected to a range of abiotic stresses as they forage for water and nutrients. Cytosolic free calcium is a common second messenger in the signaling of abiotic stress. In addition, roots take up calcium both as a nutrient and to stimulate exocytosis in growth. For calcium to fulfill its multiple roles must require strict spatio-temporal regulation of its uptake and efflux across the plasma membrane, its buffering in the cytosol and its sequestration or release from internal stores. This prompts the question of how specificity of signaling output can be achieved against the background of calcium's other uses. Threats to agriculture such as salinity, water availability and hypoxia are signaled through calcium. Nutrient deficiency is also emerging as a stress that is signaled through cytosolic free calcium, with progress in potassium, nitrate and boron deficiency signaling now being made. Heavy metals have the capacity to trigger or modulate root calcium signaling depending on their dose and their capacity to catalyze production of hydroxyl radicals. Mechanical stress and cold stress can both trigger an increase in root cytosolic free calcium, with the possibility of membrane deformation playing a part in initiating the calcium signal. This review addresses progress in identifying the calcium transporting proteins (particularly channels such as annexins and cyclic nucleotide-gated channels) that effect stress-induced calcium increases in roots and explores links to reactive oxygen species, lipid signaling, and the unfolded protein response. PMID:27621742

  5. An evaluation of potassium ions as endothelium-derived hyperpolarizing factor in porcine coronary arteries.

    Science.gov (United States)

    Bény, J L; Schaad, O

    2000-11-01

    In the rat hepatic artery, the endothelium-derived hyperpolarizing factor (EDHF) was identified as potassium. Potassium hyperpolarizes the smooth muscles by gating inward rectified potassium channels and by activating the sodium-potassium adenosine triphosphatase (Na(+)-K(+)ATPase). Our goal was to examine whether potassium could explain the EDHF in porcine coronary arteries. On coronary strips, the inhibition of calcium-dependent potassium channels with 100 nM apamin plus 100 microM charibdotoxin inhibited the endothelium-dependent relaxations, produced by 10 nM substance P and 300 nM bradykinin and resistant to nitro-L-arginine and indomethacin. The scavenging of potassium with 2 mM Kryptofix 2.2.2 abolished the endothelium-dependent relaxations produced by the kinins and resistant to nitro-L-arginine and indomethacin. Forty microM 18alpha glycyrrethinic acid or 50 microM palmitoleic acid, both uncoupling agents, did not inhibit these kinin relaxations. Therefore, EDHF does not result from an electrotonic spreading of an endothelial hyperpolarization. Barium (0.3 nM) did not inhibit the kinin relaxations resistant to nitro-L-arginine and indomethacin. Therefore, EDHF does not result from the activation of inward rectified potassium channels. Five hundred nM ouabain abolished the endothelium-dependent relaxations resistant to nitro-L-arginine and indomethacin without inhibiting the endothelium-derived NO relaxation. The perifusion of a medium supplemented with potassium depolarized and contracted a coronary strip; however, the short application of potassium hyperpolarized the smooth muscles. These results are compatible with the concept that, in porcine coronary artery, the EDHF is potassium released by the endothelial cells and that this ion hyperpolarizes and relaxes the smooth muscles by activating the Na(+)-K(+)ATPase. PMID:11053218

  6. Biochemistry of the normal dura mater of the human brain determination of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur and nitrogen contents Estudo bioquímico da dura mater normal do cérebro humano: conteúdo de água, sódio, potássio, cálcio, fósforo, magnésio, cobre ferro, enxôfre e nitrogênio

    Directory of Open Access Journals (Sweden)

    Horacio M. Canelas

    1969-06-01

    Full Text Available The concentrations of water, sodium, potassium, calcium, phosphorus, magnesium, copper, iron, sulfur, and nitrogen were determined in samples of apparently normal dura mater removed from 18 subjects recently dead by craniocerebral trauma. The average concentrations expressed in dry weight were: water 79.55 g/100 g ± 2.52; sodium 1.63 mequiv/100 g ±0.27; potassium 3.68 mequiv/100 g ± 0.66; calcium 119.84 mg/100 g ± 107.40; phosphorus 68.2 mg/100 g ± 34.5; magnesium 0.61 mequiv/100 g ± 0.37; copper 249.8 /xg/100 g ± 109.4; iron 0.82 mg/100 g ± 0.28; sulfur 490.7 mg/100 g ± 22.5; nitrogen 3.33 g/100 g ± 0.17.Foram determinadas as concentrações de água, sódio, potássio, cálcio, fósforo, magnésio, cobre, ferro, enxôfre e nitrogênio de espécimes de dura máter aparentemente normal retirados de 18 indivíduos recentemente falecidos em conseqüência de traumatismo crânio-encefálico. As concentrações médias, expressas em peso seco, foram as seguintes: água 79,55 g/100 g ± 2,52; sódio 1,63 mequiv/100 g ± 0,27; potássio 3,68 mequiv/100 g ± 0,66; cálcio 119,84 mg/100 g ± 107,40; fósforo 68,2 mg/100 g ± 34,5; magnésio 0,61 mequiv/100 g ± 0,37; cobre 249,8 mg/100 ± 109,4; ferro 0,82 mg/100 g ± 0,28; enxôfre 490,7 mg/100 g ± 22,5; nitrogênio 3,33 g/100 g ± 0,17.

  7. Trace element studies in urolithiasis; preliminary investigation on mixed calcium oxalate-struvite urinary calculi

    International Nuclear Information System (INIS)

    In this study the levels of the trace elements copper , zinc, lead, iron, aluminum, nickel, chromium along with magnesium, sodium and potassium were estimated in fifteen mixed calcium oxalate-struvite (CaOx/STR) urinary stones. The mean values of the combined results were, copper 4.24, zinc 1302, zinc 1302.10, lead 23.25, iron 36.83,nickel 0.69, chromium 1.93, magnesium 4530441, sodium 54.13 and potassium 5.93 ng mg/sup -1/. It was observed that zinc, aluminum and potassium levels were higher than in calcium oxalate(CaOx) calculi 0.05>P>0.02 and potassium levels were higher than in mixed calcium oxalate-hydroxy appetite (CaOx/APA) calculi, P<0.01. A combination of all the results was also compared with similar data from South Africa, Turkey, Austria, India, U.S.A and Japan. (author)

  8. Water Chlorination for human consumption

    International Nuclear Information System (INIS)

    Beginning from this issue, an initiative of Federgasacqua (Federal association dealing with the gas and the water) takes place through the activities of the Task Forces Water Quality Control and Materials and Processes, which aim is to offer to the water industry operators and updated information concerning some main subjects, emphasizing in particular the technical and management applied topics. The paper deals with the chlorination processes in drinking water treatment. An overview of the italian situation is presented, concerning disinfection as well as other oxidation processes, together with an historical background on chlorination. Concerning the applications, the chemical technologies and the main processes, the disinfectant effectiveness and the byproducts formation have been described. Further, the regulations in force have been reported and discussed on national and international bases

  9. Method and equipment to eliminate gaseous sulphur dioxide and chlorine components from a gas stream

    Energy Technology Data Exchange (ETDEWEB)

    Dahlstrom, D.A.; Ellison, W.S.; Wilhelm, J.H.

    1977-10-27

    The known method to clean waste gases from coal combustion which besides SO/sub 2/ still contain chlorine compounds by treatment with aqueous washing solutions is improved upon. A combination of two wash systems is suggested which are particularly economical as the washing solutions can be regenerated and recycled into the system. Calcium compounds and sodium sulphite are used, the solids formed are removed from the system. The apparatus is described.

  10. Modulation of Tartrates with Various Counterions on the Phases of Calcium Oxalate in Gelatinous Systems

    Institute of Scientific and Technical Information of China (English)

    Jian Ming OUYANG; Xiang Ping LI

    2005-01-01

    Effect of various counterions of tartrate on the crystallization of calcium oxalate in gel system was investigated using scanning electron microscopy and X-ray diffraction. Various tartrates with hydrogen (H2tart), sodium (Na2tart), potassium (K2tart), ammonium ((NH4)2tart), and a mixture of sodium and potassium cations (NaKtart) were considered. For H2tart, Na2tart, and (NH4)2tart, calcium oxalate dihydrate (COD) was induced. However, for K2tart and NaKtart,calcium oxalate trihydrate (COT) was obtained.

  11. The Medicago truncatula DMI1 protein modulates cytosolic calcium signaling

    DEFF Research Database (Denmark)

    Peiter, Edgar; Sun, Jongho; Heckmann, Anne Birgitte Lau;

    2007-01-01

    Methanobacterium thermoautotrophicum potassium channel (MthK). The cytosolic C terminus of DMI1 contains a RCK (regulator of the conductance of K+) domain that in MthK acts as a calcium-regulated gating ring controlling the activity of the channel. Here we show that a dmi1 mutant lacking the entire C terminus acts...

  12. Metabolic fate of chlorinated paraffins

    International Nuclear Information System (INIS)

    The disposition of three [1-14C]-chlorododecanes (MCDD, PCDD I and PCDD II; 17.4%, 55.9%, and 68.5% chlorination) was studied in C57Bl mice. [1-14C]-lauric acid (LA) was studied as reference compound. Fifty-two percent (MCDD), 32% (PCDD I), and 8% (PCDD II) of the radioactive doses were exhaled as 14CO2 during 12 h after i.v. injection. Similar results were obtained after p.o. administration. In addition to a marked labelling of the liver and fat, the distribution patterns observed at 24 h after administration revealed an uptake of radioactivity in tissues with high cell turnover/high metabolic activity, e.g., intestinal mucosa, bone marrow, salivary glands and thymus. The concentration of radioactivity in these sites and the exhalation of 14CO2, which were inverse to the degree of chlorination, indicate that the chloroalkanes are degraded to metabolites which can be utilized in the intermediary metabolism. A similar, although more pronounced, distribution pattern and 14CO2-exhalation (70% of i.v. dose) was observed after LA administration. The long time retention of heptane-soluble radioactivity in liver and fat (indicating unmetabolized substance) increased with degree of chlorination. On the contrary, the administration of LA and the chlorododecanes MCDD and PCDD I, but not of PCDD II, resulted in a selective labelling of the central nervous system 30-60 days after injection. (orig.)

  13. OXIDATION OF DNAPL MIXTURES USING POTASSIUM PERMANGANATE WITH A PHASE-TRANSFER-CATALYST:KINETIC RESULTS FROM A DIGITAL PHOTOGRAPHIC MONITORING METHOD

    Science.gov (United States)

    There has been considerable interest in the use of potassium permanganate for the in-situ destruction of chlorinated solvernt.At the present stage of development, significant opportunities remain in increasing the overall efficiency of flooding schemes and in speeding up the oxi...

  14. Catalytic hydrogen-chlorine exchange between chlorinated hydrocarbons under oxygen-free conditions

    NARCIS (Netherlands)

    van der Heijden, A.W.A.M.; Podkolzin, S.G.; Jones, M.E.; Bitter, J.H.; Weckhuysen, B.M.

    2008-01-01

    Chlorinated hydrocarbons (CHCs) remain important industrial chemical intermediates and solvents, especially for the exploration of the potential of La-based materials for the conversion of chlorinated waste compounds.[1] The production of industrially important CHCs frequently occurs with concurrent

  15. 21 CFR 172.375 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodide. 172.375 Section 172.375 Food and... Dietary and Nutritional Additives § 172.375 Potassium iodide. The food additive potassium iodide may be safely used in accordance with the following prescribed conditions: (a) Potassium iodide may be...

  16. Fracturing graphene by chlorination: a theoretical viewpoint

    OpenAIRE

    Ijäs, M.; Havu, P.; Harju, A.

    2012-01-01

    Motivated by the recent photochlorination experiment [B. Li et al., ACS Nano 5, 5957 (2011)], we study theoretically the interaction of chlorine with graphene. In previous theoretical studies, covalent binding between chlorine and carbon atoms has been elusive upon adsorption to the graphene basal plane. Interestingly, in their recent experiment, Li et al. interpreted their data in terms of chemical bonding of chlorine on top of the graphene plane, associated with a change from sp2 to sp3 in ...

  17. The continuous chlorination of plutonium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, M.J.

    1959-08-14

    Previous reports on the chlorination of plutonium dioxide describe numerous small-scale experiments and a few fair-sized batch preparations. The chemistry of chlorination by numerous reagents is covered, but no process had received sufficient study for large-scale preparation of anhydrous plutonium trichloride. The literature search revealed no extensive studies on chlorination rates, exhaust gas filtering, atmospheric requirements, reactor materials, etc. A program was undertaken to select a chlorination process, to develop the necessary information for defining operating conditions and equipment specifications, and then to demonstrate the operation of the process.

  18. Calcium and bones (image)

    Science.gov (United States)

    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 ...

  19. Coronary Calcium Scan

    Science.gov (United States)

    ... 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 ...

  20. Calcium hydroxide poisoning

    Science.gov (United States)

    Hydrate - calcium; Lime milk; Slaked lime ... Calcium hydroxide ... These products contain calcium hydroxide: Cement Limewater Many industrial solvents and cleaners (hundreds to thousands of construction products, flooring strippers, brick cleaners, cement ...

  1. Calcium source (image)

    Science.gov (United States)

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

  2. Calcium in diet

    Science.gov (United States)

    Diet - calcium ... Calcium is one of the most important minerals for the human body. It helps form and maintain healthy teeth and bones. A proper level of calcium in the body over a lifetime can help ...

  3. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... Patient / Caregiver Diseases & Conditions Calcium Pyrophosphate Deposition (CPPD) Calcium Pyrophosphate Deposition (CPPD) Fast Facts The risk of ... young people, too. Proper diagnosis depends on detecting calcium pyrophosphate crystals in the fluid of an affected ...

  4. Bioinspired Artificial Sodium and Potassium Ion Channels.

    Science.gov (United States)

    Rodríguez-Vázquez, Nuria; Fuertes, Alberto; Amorín, Manuel; Granja, Juan R

    2016-01-01

    In Nature, all biological systems present a high level of compartmentalization in order to carry out a wide variety of functions in a very specific way. Hence, they need ways to be connected with the environment for communication, homeostasis equilibrium, nutrition, waste elimination, etc. The biological membranes carry out these functions; they consist of physical insulating barriers constituted mainly by phospholipids. These amphipathic molecules spontaneously aggregate in water to form bilayers in which the polar groups are exposed to the aqueous media while the non-polar chains self-organize by aggregating to each other to stay away from the aqueous media. The insulating properties of membranes are due to the formation of a hydrophobic bilayer covered at both sides by the hydrophilic phosphate groups. Thus, lipophilic molecules can permeate the membrane freely, while the small charged or very hydrophilic molecules require the assistance of other membrane components in order to overcome the energetic cost implied in crossing the non-polar region of the bilayer. Most of the large polar species (such as oligosaccharides, polypeptides or nucleic acids) cross into and out of the cell via endocytosis and exocytosis, respectively. Nature has created a series of systems (carriers and pores) in order to control the balance of small hydrophilic molecules and ions. The most important structures to achieve these goals are the ionophoric proteins that include the channel proteins, such as the sodium and potassium channels, and ionic transporters, including the sodium/potassium pumps or calcium/sodium exchangers among others. Inspired by these, scientists have created non-natural synthetic transporting structures to mimic the natural systems. The progress in the last years has been remarkable regarding the efficient transport of Na(+) and K(+) ions, despite the fact that the selectivity and the ON/OFF state of the non-natural systems remain a present and future challenge

  5. Reduction of Aldehydes and Ketones with Potassium Borohydride as Reductant

    Institute of Scientific and Technical Information of China (English)

    罗慧谋; 李毅群

    2005-01-01

    A series of aldehydes and ketones were reduced by potassium borohydride in an ionic liquid/water ([bmim]PF6/H2O) biphasic system to afford corresponding alcohol with high purity in excellent yields. The ionic liquid/water biphasic system could promote the chemoselectivity and the substituents such as nitro group and chlorine remained intact. Aromatic ketones were not as active as aromatic aldhydes and cyclic ketones owing to their higher steric hindrance. The ionic liquid could be recycled and reused. This protocol has notable advantages of no need of phase transfer catalyst and organic solvents, mild conditions, simple operation, short reaction time, ease work-up, high yields and recycling of the ionic liquid.

  6. Behavior of chlorine in lake water

    International Nuclear Information System (INIS)

    Water from monsoon fed Sagre lake is being used as a source of raw water for Tarapur Atomic Power Station (TAPS--1 and 2). The raw water from the lake is initially pumped to Sagre water treatment plant (SWTP) operated by Maharashtra Industrial Development Corporation (MIDC) from where, the processed water is sent to cater the needs of both the units of TAPS-1 and 2, townships of TAPS and MIDC, and the nearby villages. At the SWTP the raw water is treated with alum to remove the turbidity, filtered and chlorinated using bleaching powder. All these years the raw water is chlorinated in such a way whereby a residual chlorine level of 0.5-1.0 mg/l, is maintained at the outlet of water treatment plant. The adequacy of the current chlorination practice was investigated, at the request of the NPC-500 MWe group during 1990, so that the future requirements of raw water for TAPP-3 and 4, can be met from the expanded SWTP. In this connection experiments on chlorine dose -- residual chlorine relationship and the decay pattern of chlorine with time was carried out in the lake water (with low value of total dissolved solids and total hardness 3 sample at the site. The total bacterial count in the raw water observed to be 107 counts/ml originally came down to 103 counts/ml at the end of one-hour exposure time to chlorine. It was found that the chlorine demand of the water was around 6 mg/l. In addition Jar test to evaluate the aluminum dose was also carried out. Based on these experiments a chlorine dose of 6 mg/l for one hour contact time was arrived at. The experimental findings were in agreement with the current chlorination practices. (author)

  7. Chlorine dioxide and by-products in water distribution systems

    OpenAIRE

    Ferreira, Francisco Cardoso

    1991-01-01

    Chlorine dioxide is used as both a pre-oxidant and/or a post-disinfectant in several water treatment plants in the United States. Chlorine dioxide is associated with its byproducts chlorite and chlorate. Chlorine dioxide, chlorine, chlori te and chlorate were sampled in four distribution systems where chlorine dioxide is used for disinfection purposes: Charleston, WV, Columbus, GA, New Castle, PA, and Skagit, WA. The fate of chlorine dioxide and its by-products in dist...

  8. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne;

    2003-01-01

    The propagation of mechanically induced intercellular calcium waves (ICW) among osteoblastic cells occurs both by activation of P2Y (purinergic) receptors by extracellular nucleotides, resulting in "fast" ICW, and by gap junctional communication in cells that express connexin43 (Cx43), resulting in...... extracellular calcium, plasma membrane depolarization by high extracellular potassium, and the L-type voltage-operated calcium channel inhibitor, nifedipine. In contrast, all these treatments enhanced the spread of P2 receptor-mediated ICW in UMR rat osteoblastic cells. Using UMR cells transfected to express Cx......43 (UMR/Cx43) we confirmed that nifedipine sensitivity of ICW required Cx43 expression. In human osteoblastic cells, gap junction-dependent ICW also required activation of L-type calcium channels and influx of extracellular calcium....

  9. Inactivation of simian rotavirus SA11 by chlorine, chlorine dioxide, and monochloramine.

    OpenAIRE

    Berman, D.; Hoff, J C

    1984-01-01

    The kinetics of inactivation of simian rotavirus SA11 by chlorine, chlorine dioxide, and monochloramine were studied at 5 degrees C with a purified preparation of single virions and a preparation of cell-associated virions. Inactivation of the virus preparations with chlorine and chlorine dioxide was studied at pH 6 and 10. The monochloramine studies were done at pH 8. With 0.5 mg of chlorine per liter at pH 6, more than 4 logs (99.99%) of the single virions were inactivated in less than 15 s...

  10. An overview study of chlorination reactions applied to the primary extraction and recycling of metals and to the synthesis of new reagents

    International Nuclear Information System (INIS)

    Energy intensive classical metallurgical processes, the depletion of high-grade ores and primary sources push the scientific and technical communities to treat lean and complex ores as well as secondary metal resources for the recovery of valuable metals. Chlorination technique could be a suitable technology for this purpose. This paper summarizes laboratory experimentation of chlorination processes developed for the extraction of tantalum and niobium from their bearing materials, the upgrading of chromite, the treatment of sulfide concentrates, and the decontamination of jarosite, as well as for the synthesis of potassium ferrate. Each investigation started by a thermodynamic study of different systems (M-O-Cl, M-S-Cl, M = metal) including the calculations of the standard free energy of chlorination reactions and phase stability diagrams of these systems. The kinetics of these chlorination reactions was studied by thermogravimetric analysis. The effects of total gas flow rate, temperature, individual reactant partial pressures, etc., on the chlorination reaction rate were investigated. Besides, experiments were also conducted in tubular furnaces. Several different qualitative and quantitative analyses methods were used to evaluate the selectivity and performance of the chlorination processes. The results reported in this paper show the advantages of the chlorination technology in terms of energy saving, selectivity of the processes, and recovery rate of valuable metals. They also demonstrate the possibility to treat lean raw materials, to improve the decontamination of wastes, to generate environmentally safer residues, to engineer new compounds, etc.

  11. Mercury Control with Calcium-Based Sorbents and Oxidizing Agents

    Energy Technology Data Exchange (ETDEWEB)

    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

  12. 21 CFR 173.300 - Chlorine dioxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Chlorine dioxide. 173.300 Section 173.300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Specific Usage Additives § 173.300 Chlorine...

  13. Chlorine demand and residual chlorine decay kinetics of Kali river water at Kaiga project area

    International Nuclear Information System (INIS)

    The nuclear power plant at Kaiga would use Kali river water for condenser cooling. This necessitated studies on the chemistry of chlorination such as chlorine demand, kinetics of chlorination and other water characteristics aimed at obtaining base line data. The study revealed significant seasonal variation of chlorine demand ranging from 0.5 ppm to 1.7 ppm (3.0 ppm dose, 30 min contact time) and total consumption of 5.0 ppm (10.0 ppm dose, 48 hours contact time). The reaction follows first order kinetics in chlorine. High correlation of chlorine demand with chlorophyll a, suspended matter, turbidity, silica, nitrite, phosphate and sulphate indicated that chlorine demand is greatly influenced by water quality. (author). 3 refs., 1 tab

  14. Internal chlorination of Ni-Cr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Berztiss, D.; Hennesen, K.; Grabke, H.J. [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany)

    1998-12-31

    In contrast to internal oxidation, sulfidation and carburization, very little information is available regarding internal chlorination, especially diffusion of chlorine in metallic alloys. This paper describes results of experiments on Ni-Cr alloys (<10 wt% Cr) exposed in an atmosphere containing radioactive HCl. The diffusion of chlorine in the alloy can be determined by measurement of residual {beta}-activity from the sample surface. Successively thin layers (0.5-10 {mu}m) of the alloy were removed by lapping and the surface activity was measured to obtain a depth profile. Both single and polycrystalline materials were tested. Through this work it should be determined if there is in fact solubility and diffusion of chlorine in Ni-based alloys as some authors have proposed or if the ingress of chlorine is mainly a grain boundary phenomenon. (orig.)

  15. Chlorine

    Science.gov (United States)

    ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Updates Subscribe Listen Page last reviewed April ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Download page Subscribe to RSS Get email ...

  16. Effects of Vitamin C and Hydrogen Dioxide on the Electric Current of Large-conductance Calcium-activated Potassium Channels in Isolated Outer Hair Cells of Old Guinea Pigs’ Cochlears%维生素C与过氧化氢对老年豚鼠耳蜗外毛细胞大电导钙激活钾通道电流的影响

    Institute of Scientific and Technical Information of China (English)

    赖丹; 黄非; 覃纲

    2015-01-01

    目的:研究过氧化氢(H2 O2)及维生素C对老年豚鼠耳蜗外毛细胞大电导钙激活钾通道(large con‐ductance Ca2+-activated potassium channels ,BKCa channels)电流的影响及其机制。方法采用急性酶分离方法分离25只老年豚鼠耳蜗外毛细胞,以膜片钳全细胞记录方式观察BKCa通道电流(5只豚鼠);记录到稳定、正常的BKCa通道电流后,向新鲜分离贴壁外毛细胞的2 ml浴槽的浴液中加入H2 O2稀释液40μl ,使浴液中H2 O2浓度为4μmol/L ,观察H2 O2对BKCa通道电流的影响(5只豚鼠);再分组加入维生素C溶液10、20、40μl (各组5只豚鼠),使浴液中维生素C终浓度分别为25、50、100μg/ml ,观察 H2 O2和维生素C联合作用对BKCa通道电流的影响。结果①膜片钳全细胞记录模式下,记录到一串幅值较大、快速激活、几乎不失活的电流,激活电压大于-40~-30 mV ,电流随膜电位的增加而增强,并表现出外向整流的特性;加入BKCa通道特异性阻断剂伊比利亚毒素(iberiotoxin ,IbTX)100 nmol/L后,通道活动完全阻断,证实为BKCa通道电流。②加入 H2 O2后,用药3分钟内,当VT为+50 mV时,BKCa通道峰值电流密度最大值从22.09±0.27 pA/pF升至43.53±1.09 pA/pF ,增幅97.06%。H2 O2 4μmol/L+25、50、100μg/ml维生素C时,BKCa通道电流表现浓度依赖性抑制,电流幅值和峰值电流密度随着维生素C浓度增加而减小,I-V曲线下降,洗脱后仍不能恢复至加药前正常水平。结论老年豚鼠耳蜗外毛细胞存在氧自由基/BKCa途径,而维生素C可减轻氧自由基对外毛细胞BKCa通道的影响。%Objective To study the effects of hydrogen dioxide (oxygen free radical donator) and vitamin C (oxygen free radical scavenger) on the electric current of large conductance calcium -activated potassium channels (BKCa channels) in isolated

  17. Calcium and Vitamin D

    Science.gov (United States)

    ... Home › Patients › Treatment › Calcium/Vitamin D Calcium/Vitamin D Getting enough calcium and vitamin D is essential ... counter medications and calcium supplements. What is Vitamin D and What Does it Do? Vitamin D plays ...

  18. Changes in intracellular calcium in brain cells of aged rats

    Institute of Scientific and Technical Information of China (English)

    Yu Li; Yunpeng Cao

    2008-01-01

    BACKGROUND: Studies have shown that voltage-dependent calcium influx, and enhancement of certain calcium-dependent processes in neurons, is related to aging. OBJECTIVE: To observe changes in intracellular calcium ([Ca2+]i) in neurons of aged rats, and to compare with young rats. DESIGN, TIME AND SETTING: A randomized control experiment of neurophysiology was performed at the Central Laboratory of School of Pharmaceutical Science, China Medical University from June to August 2004. MATERIALS: Ten male, healthy, Wistar rats, 19 months old, were selected for the aged group. Ten male, 3-month-old, Wistar rats were selected for the young control group. Fura-2/AM was provided by the Institute of Pharmaceutical Research of Chinese Academy of Medical Sciences, and the F-2000 fluorospectrophotometer was a product of Hitachi, Japan. METHODS: Fluorescence Fura-2 spectrophotometer was used to measure [Ca2+]i in acutely dissociated brain cells of aged and young rats. The concentration of extracellular potassium was controlled by adding different volumes of chloridated potassium solution of high concentration. MAIN OUTCOME MEASURES: [Ca2+]i in neurons of young and aged rats in the presence of 1 mmol/L extracellular calcium concentration and 0 mmol/L (resting state), 5, 10, 20, and 40 mmol/L extracellular potassium. Absolute increase of [Ca2+]i in neurons of young and aged rats when extraceUular potassium was 5,10,20, 40 mmol/L. RESULTS: In the presence of 1 mmol/L extracellular Ca2+ and 0 mmol/L (resting state), 5, 10, 20, and 40 mmol/L extracellular potassium, [Ca2+]i in the neurons of aged rats was significantly less than that in young rats (P 0.05). CONCLUSION: The overload of [Ca2+]i in neurons of aged rats is greater than that of young rats under the same circumstances.

  19. Effects of different phosphorus and potassium fertilization on contents and uptake of macronutrients (N, P, K, Ca, Mg in winter wheat I. Content of macronutrients

    Directory of Open Access Journals (Sweden)

    Renata GAJ

    2014-12-01

    Full Text Available The aim of the study carried out under field conditions was to evaluate the effect of differentiated phosphorus and potassium fertilization level on nutritional status of winter wheat at stem elongation (BBCH 31 and flowering (BBCH 65 development stages as well as on macronutrient contents in yield obtained (grain and straw. The research was conducted in 2007-2010, within an individual agricultural holding, on lessive soil with medium and high richness in potassium and phosphorus, respectively. The contents of nitrogen, phosphorus, potassium, magnesium and calcium in wheat changed depending on the organ assessed and plant development stage. At BBCH 31, regardless fertilization level, the plants observed were malnourished with potassium, phosphorus and calcium and at the control site also with nitrogen. Furthermore, there were found significant correlation relationships among the contents of nutrient pairs: nitrogen-potassium, nitrogen-phosphorus, nitrogen-magnesium and nitrogen-calcium. The content of nitrogen in wheat grain and straw differed mainly due to weather conditions during the study. Irrespective of the years of observation, differentiated rates of P and K applied had no significant effect on N accumulation in wheat at full ripening stage. In contrast to nitrogen, the level of P and K fertilization significantly differentiated the contents of phosphorus, potassium and magnesium in wheat grain and straw. In case of calcium, the effect of fertilization factor was indicated only as regards the content of this nutrient in grain.

  20. Importance of Calcium

    OpenAIRE

    TANDOĞAN, Berivan; ULUSU, N. Nuray

    2005-01-01

    Calcium is the most abundant mineral in the body. Calcium regulates many cellular processes and has important structural roles in living organisms. Skeletal muscle structure and function, polymerisation of fibrin and the conduction of impulses in the nervous system are regulated by calcium. Calcium is an important intracellular messenger in protozoa, plants, and animals. Calcium-transporting systems which are located in the plasma membrane and in the organelles, regulate the ionic concentrati...

  1. 钠钾镁钙葡萄糖注射液对创伤失血性休克兔复苏过程中血流动力学、血糖和酸碱平衡的影响%The effects of Sodium Potassium Magnesium, Calcium and Glucose Injection on hemodynamics, blood glucose and the acid-base balance in rabbits with traumatic hemorrhagic shock LI

    Institute of Scientific and Technical Information of China (English)

    李芹; 刘慧; 周莹; 许铁

    2015-01-01

    Objective To explore the effects of Sodium Potassium Magnesium, Calcium and Glucose Injection on hemodynamics, blood glucose and the acid-base balance in rabbits with traumatic hemorrhagic shock (THS). Methods We induced THS by Lamson’s method. We divided the rabbits into four groups (n=8):NC group, NS group, LR group and SPMCG group. Different interventions on limited resuscitation phase were performed respectively. The same interventions were performed on full resuscitation phase. The blood samples Were collected at pre-shock,post-shock,the end of limited resuscitation and full resuscitation for blood gas analysis. Results MAP, HR, RF, PaCO2 and the blood glucose in infusion groups there were no significant differences (P>0.05). After the fluid resuscitation, compared with NS group and LR group, pH, the blood lactate (Lac) and base excess (BE) in SPMCG group had been significantly improved (P0.05). Conclusion In the fluid resuscitation of traumatic hemorrhagic shock rabbits, compared with saline solution and lactated Ringer’s, sodium potassium magnesium calcium and glucose injection is more advantageous to maintain the acid-base balance.%目的:探讨钠钾镁钙葡萄糖注射液对创伤失血性休克兔血流动力学、血糖和酸碱平衡的影响。方法采用Lamson’s法制作创伤失血性休克兔模型。日本长耳大白兔32只随机均分为4组:正常对照(NC)组,生理盐水(NS)组,乳酸钠林格氏液(LR)组,钠钾镁钙葡萄糖注射液(SPMCG)组;在限制复苏期给予不同干预,在充分复苏期给予相同干预;于休克前即基础期(T1)、休克末(T2)、限制复苏期末(T3)、充分复苏期末(T4)各时间点采动脉血进行血气分析。结果输液各组平均动脉压(MAP)、心率(HR)、呼吸频率(RF)、动脉血二氧化碳分压(PaCO2)以及血糖组间比较差异无统计学意义(P>0.05)。经液体复苏后, SPMCG组实验动物的pH

  2. Mass spectrometric isotope dilution analysis of small calcium concentrations in minerals

    International Nuclear Information System (INIS)

    A mass spectrometric isotope dilution analysis for the determination of small calcium contents is developed. The different steps (decomposition of the mineral including isotope dilution technique, calcium separation and mass spectrometric measurement) of the analytical procedure are described. For a 42Ca spike the optimum spike addition is calculated. The dependence of the analysis error on the mass spectrometric measurements is discussed. Using a chromatographic method with a strong acidic ion exchanger calcium can be completely separated from potassium. The calcium content in the range of 0.15-0.004% of two feldspars and of one lepidolite is determined with external relative standard deviations of 0.9-5.1%. (orig.)

  3. Inhibition of calcium currents in cultured rat dorsal root ganglion neurones by (-)-baclofen.

    OpenAIRE

    Dolphin, A.C.; Scott, R. H.

    1986-01-01

    Voltage-dependent inward calcium currents (ICa) activated in cultured rat dorsal root ganglion neurones were reversibly reduced in a dose-dependent manner by (-)-baclofen (10 microM to 100 microM). Baclofen (100 microM) reduced the calcium-dependent slow outward potassium current (IK(Ca)). This current was abolished in calcium-free medium and by 300 microM cadmium chloride. The action of baclofen on IK(Ca) was reduced when the calcium concentration in the medium was increased from 5 mM to 30 ...

  4. Intracellular calcium modulates basolateral K(+)-permeability in frog skin epithelium

    DEFF Research Database (Denmark)

    Brodin, Birger; Rytved, K A; Nielsen, R

    1994-01-01

    Cytosolic calcium ([Ca2+]i) has been suggested as a key modulator in the regulation of active sodium transport across electrically "tight" (high resistance) epithelia. In this study we investigated the effects of calcium on cellular electrophysiological parameters in a classical model tissue, the...... frog skin. [Ca2+]i was measured with fura-2 in an epifluorescence microscope setup. An inhibition of basolateral potassium permeability was observed when cytosolic calcium was increased. This inhibition was reversible upon removal of calcium from the serosal solution....

  5. Depolarization-induced contractile activity of smooth muscle in calcium-free solution.

    Science.gov (United States)

    Mangel, A W; Nelson, D O; Rabovsky, J L; Prosser, C L; Connor, J A

    1982-01-01

    In calcium-free solution, strips of cat intestinal muscle developed slow, rhythmic electrical potential changes that triggered contractions. Some strips failed to develop spontaneous electrical activity in calcium-free solution but responded with contractions to depolarization by direct electrical stimulation or by treatment with barium chloride, potassium chloride, or acetylcholine. Similar results were obtained with segments of cat stomach, colon, esophagus, bladder, uterus, and vena cava, as well as with rabbit vena cava. In calcium-free saline, rat small intestinal muscle showed fast electrical activity with accompanying development of a tetanuslike contraction. After 60 min in calcium-free solution, cat small intestinal muscle retained 17.7% of its original concentration of calcium. It is concluded that in some smooth muscles, depolarization-triggered release of intracellular calcium does not require an associated influx of calcium. PMID:7058877

  6. The effect of foliar feeding of potassium salts and urea in spinach on gas exchange, leaf yield and quality

    Directory of Open Access Journals (Sweden)

    Edward Borowski

    2012-12-01

    Full Text Available In a pot experiment conducted in a phytotron, the effectiveness of foliar feeding of different potassium salts, with and without the addition of 0.5% CO(NH22, in spinach (Spinacia oleracea L. was investigated. Potassium was applied 3 times in the form of 1% solutions KCl, KNO3, K2SO4 and C6H5K3O7•H2O, compared to water as the control treatment. The obtained results show that foliar feeding of potassium salts in spinach is an efficient method of supplementing the level of K+ in plants during vegetation. Plants fed with KNO3 had the highest content of potassium in leaves, and those fertilized with K2SO4, C6H5K3O7 × H2O and KCl had an only slightly lower potassium content. The application of potassium salts resulted in more intensive gas exchange in leaves (stomatal conductance, photosynthesis, transpiration and, as a consequence of that, increased leaf yield. Potassium nitrate and citrate influenced most effectively the abovementioned processes. The treatment of spinach with potassium salts resulted in an increased content of protein, chlorophyll, carotenoids, nitrates and iron as well as a decreased content of vitamin C and calcium in leaves.

  7. Increased serum potassium affects renal outcomes

    DEFF Research Database (Denmark)

    Miao, Y; Dobre, D; Heerspink, H J Lambers; Brenner, B M; Cooper, M E; Parving, Hans-Henrik Dyring; Shahinfar, S; Grobbee, D; de Zeeuw, D

    2011-01-01

    To assess the effect of an angiotensin receptor blocker (ARB) on serum potassium and the effect of a serum potassium change on renal outcomes in patients with type 2 diabetes and nephropathy.......To assess the effect of an angiotensin receptor blocker (ARB) on serum potassium and the effect of a serum potassium change on renal outcomes in patients with type 2 diabetes and nephropathy....

  8. Modeling surface disinfection kinetics of fresh tomato (Lycopersicum esculentum using chlorine solutions

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Solano Cornejo

    2013-03-01

    Full Text Available Fresh tomatoes Italian variety were subjected to surface disinfection processes using calcium hypochlorite solutions to determine their germicidal efficiency and kinetics that governs the surface inactivation process in aerobic mesophilic bacteria, yeasts and molds. Chlorine as surface disinfectant was effective against aerobic mesophilic bacteria, yeasts and molds in this order, the resistance of aerobic mesophilic bacteria, yeasts and molds of their values expressed in zchlorine was 455, 500 and 625 ppm respectively. Aerobic mesophilic bacteria present in the tomato surface show a higher resistance to chlorine disinfection according contact time germtomato skin is greater due to a better adherence to the tomato skin making it difficult for the action of chlorine on germs; this effect is not present in the case of yeasts or molds. Experimental Dchlorine 20°C values and Dchlorine_20°C values predicted by the First Bigelow’s Model were fit with a correlation of between 0.91 and 0.99. The experimental zchlorine values and values zchlorine predicted by the Second Bigelow’s Model were adjusted with a correlation of 0.72 to 0.86. The variability in the values zchlorine was because germs analyzed to validate the proposed model were composed of various genera. So, the Bigelow’s Method applied to inactivation kinetics of surface chlorine was validated.

  9. Potassium and High Blood Pressure

    Science.gov (United States)

    ... Pressure Tools & Resources Stroke More Potassium and High Blood Pressure Updated:Mar 1,2016 A diet that includes ... was last reviewed on 08/04/2014. High Blood Pressure • Home • About High Blood Pressure (HBP) • Why HBP ...

  10. Status of potassium permanganate - 2008

    Science.gov (United States)

    This is a brief overview of the Technical Sections completed and being worked on for the New Animal Drug Application (NADA) for potassium permanganate will be presented. Initial Label Claim (Columnaris on catfish/HSB): 1) Human Food Safety - Complete for all fin fish (June 1999). A hazard charac...

  11. 21 CFR 172.730 - Potassium bromate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium bromate. 172.730 Section 172.730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Specific Usage Additives § 172.730 Potassium bromate. The food additive potassium bromate may be...

  12. 21 CFR 182.3640 - Potassium sorbate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium sorbate. 182.3640 Section 182.3640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Potassium sorbate. (a) Product. Potassium sorbate. (b) Conditions of use. This substance is...

  13. 21 CFR 172.160 - Potassium nitrate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium nitrate. 172.160 Section 172.160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Preservatives § 172.160 Potassium nitrate. The food additive potassium nitrate may be safely used as a...

  14. 21 CFR 582.5634 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium iodide. 582.5634 Section 582.5634 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent....

  15. 75 FR 51112 - Potassium Permanganate From China

    Science.gov (United States)

    2010-08-18

    ... COMMISSION Potassium Permanganate From China AGENCY: United States International Trade Commission. ACTION: Scheduling of an expedited five-year review concerning the antidumping duty order on potassium permanganate... whether revocation of the antidumping duty order on potassium permanganate from China would be likely...

  16. Use of Potassium Citrate to Reduce the Risk of Renal Stone Formation During Spaceflight

    Science.gov (United States)

    Whitson, P. A.; Pietrzyk, R. A.; Sams, C. F.; Jones, J. A.; Nelman-Gonzalez, M.; Hudson, E. K.

    2008-01-01

    Introduction: NASA s Vision for Space Exploration centers on exploration class missions including the goals of returning to the moon and landing on Mars. One of NASA s objectives is to focus research on astronaut health and the development of countermeasures that will protect crewmembers during long duration voyages. Exposure to microgravity affects human physiology and results in changes in the urinary chemical composition favoring urinary supersaturation and an increased risk of stone formation. Nephrolithiasis is a multifactorial disease and development of a renal stone is significantly influenced by both dietary and environmental factors. Previous results from long duration Mir and short duration Shuttle missions have shown decreased urine volume, pH, and citrate levels and increased calcium. Citrate, an important inhibitor of calcium-containing stones, binds with urinary calcium reducing the amount of calcium available to form stones. Citrate inhibits renal stone recurrence by preventing crystal growth, aggregation, and nucleation and is one of the most common therapeutic agents used to prevent stone formation. Methods: Thirty long duration crewmembers (29 male, 1 female) participated in this study. 24-hour urines were collected and dietary monitoring was performed pre, in, and postflight. Crewmembers in the treatment group received two potassium citrate (KCIT) pills, 10 mEq/pill, ingested daily beginning 3 days before launch, all inflight days and through 14 days postflight. Urinary biochemical and dietary analyses were completed. Results: KCIT treated subjects exhibited decreased urinary calcium excretion and maintained the levels of calcium oxalate supersaturation risk at their preflight levels. The increased urinary pH levels in these subjects reduced the risk of uric acid stones. Discussion: The current study investigated the use of potassium citrate as a countermeasure to minimize the risk of stone formation during ISS missions. Results suggest that

  17. A comparison of the virucidal properties of chlorine, chlorine dioxide, bromine chloride and iodine.

    OpenAIRE

    Taylor, G R; Butler, M

    1982-01-01

    Chlorine dioxide, bromine chloride and iodine were compared with chlorine as virucidal agents. Under optimal conditions all disinfectants were effective at low concentrations, but each disinfectant responded differently to acidity and alkalinity. Disinfection by chlorine was impaired by the presence of ammonia, but the other disinfectants retained much of their potency. Disinfection of poliovirus by iodine resulted in structural changes in the virions as seen by electron micrroscopy, but the ...

  18. Catalytic hydrogen-chlorine exchange between chlorinated hydrocarbons under oxygen-free conditions

    OpenAIRE

    van der Heijden, A.W.A.M.; Podkolzin, S.G.; Jones, M. E.; Bitter, J.H.; Weckhuysen, B. M.

    2008-01-01

    Chlorinated hydrocarbons (CHCs) remain important industrial chemical intermediates and solvents, especially for the exploration of the potential of La-based materials for the conversion of chlorinated waste compounds.[1] The production of industrially important CHCs frequently occurs with concurrent formation of less desirable side-products. For example, mixtures of chlorinated C1 and C2 hydrocarbons are still formed as by-products in industrial processes such as the production of vinyl chlor...

  19. Formation of Chloroform and Other Chlorinated Byproducts by the Chlorination of Antibacterial Products

    OpenAIRE

    Fiss, Edward Matthew

    2006-01-01

    Triclosan is a widely used antibacterial agent found in many personal hygiene products. While it has been established that pure triclosan and free chlorine readily react, interactions between triclosan-containing products and free chlorine have not previously been analyzed. Sixteen double-blinded solutions including both triclosan-containing (1.14-3.12 mg triclosan/g product) and triclosan-free products were contacted with free chlorine. Products detected included (chlorophenoxy)phenols, ...

  20. Chlorine demand studies: a need for optimisation of chlorine doses for biofouling control

    International Nuclear Information System (INIS)

    Studies on chlorine demand, chlorine decay, rate of HOBr formation and speciation of chlorine residuals of cooling water from Madras Atomic Power Station (MAPS) were carried out. April to September was found to be a high demand period. The rate of reaction is faster and also initial demand is relatively high for this seawater as compared to other sea areas. Decay occurs in two phases, the first being instantaneous and the second being very slow. (author). 9 refs., 1 fig

  1. Chlorination of organic material in different soil types

    OpenAIRE

    Gustavsson, Malin

    2009-01-01

    Research has shown that formation of chlorinated organic matter occurs naturally and that organic chlorine is as abundant as the chloride ion in organic soils. A large number of organisms are known to convert inorganic chloride (Clin) to organic chlorine (Clorg) (e.g. bacteria, lichen, fungi and algae) and some enzymes associated to these organisms are capable of chlorinating soil organic matter. The aim with the study was to compare organic matter chlorination rates in soils from several dif...

  2. Thorium electrode potentials in equimolar melt of potassium and sodium bromides

    International Nuclear Information System (INIS)

    The equilibrium electrode potentials of thorium in an equimolar mixture of potassium and sodium bromides are measured for 700, 800 and 900 deg C within the concentration range from 0.3 to 3.0 molar %. Th. The bi - and tetravalent ions are found to dominate in equilibrium with the metal. Temperature dependence of the equilibrium constant of reaction Th(solid) + Th4+(melt) reversible 2 Th2+(melt) is obtained and the conventional standard thorium electrode potentials with respect to its bi - and tetravalent ions are measured. Upon replacement of chlorine aniones by bromine ones the reaction shifted to the right hand side. Experimental data enabled to estimate the thermodynamics of mixing liquid thorium tetrabromide with the melted mixture of potassium and sodium bromides

  3. Shelf-Life of Chlorine Solutions Recommended in Ebola Virus Disease Response.

    Directory of Open Access Journals (Sweden)

    Qais Iqbal

    Full Text Available In Ebola Virus Disease (EVD outbreaks, it is widely recommended to wash living things (handwashing with 0.05% (500 mg/L chlorine solution and non-living things (surfaces, personal protective equipment, dead bodies with 0.5% (5,000 mg/L chlorine solution. Chlorine solutions used in EVD response are primarily made from powdered calcium hypochlorite (HTH, granular sodium dichloroisocyanurate (NaDCC, and liquid sodium hypochlorite (NaOCl, and have a pH range of 5-11. Chlorine solutions degrade following a reaction highly dependent on, and unusually sensitive to, pH, temperature, and concentration. We determined the shelf-life of 0.05% and 0.5% chlorine solutions used in EVD response, including HTH, NaDCC, stabilized NaOCl, generated NaOCl, and neutralized NaOCl solutions. Solutions were stored for 30 days at 25, 30, and 35°C, and tested daily for chlorine concentration and pH. Maximum shelf-life was defined as days until initial concentration fell to 30 days. Models were developed for solutions with maximum shelf-lives between 1-30 days. Extrapolating to 40°C, the maximum predicted shelf-life for 0.05% and 0.5% NaDCC solutions were 0.38 and 0.82 hours, respectively; predicted shelf-life for 0.05% and 0.5% generated NaOCl solutions were >30 and 5.4 days, respectively. Each chlorine solution type offers advantages and disadvantages to responders, as: NaDCC is an easy-to-import high-concentration effervescent powder; HTH is similar, but forms a precipitate that may clog pipes; and, NaOCl solutions can be made locally, but are difficult to transport. We recommend responders chose the most appropriate source chlorine compound for their use, and ensure solutions are stored at appropriate temperatures and used or replaced before expiring.

  4. Shelf-Life of Chlorine Solutions Recommended in Ebola Virus Disease Response

    Science.gov (United States)

    Iqbal, Qais; Lubeck-Schricker, Maya; Wells, Emma; Lantagne, Daniele

    2016-01-01

    In Ebola Virus Disease (EVD) outbreaks, it is widely recommended to wash living things (handwashing) with 0.05% (500 mg/L) chlorine solution and non-living things (surfaces, personal protective equipment, dead bodies) with 0.5% (5,000 mg/L) chlorine solution. Chlorine solutions used in EVD response are primarily made from powdered calcium hypochlorite (HTH), granular sodium dichloroisocyanurate (NaDCC), and liquid sodium hypochlorite (NaOCl), and have a pH range of 5–11. Chlorine solutions degrade following a reaction highly dependent on, and unusually sensitive to, pH, temperature, and concentration. We determined the shelf-life of 0.05% and 0.5% chlorine solutions used in EVD response, including HTH, NaDCC, stabilized NaOCl, generated NaOCl, and neutralized NaOCl solutions. Solutions were stored for 30 days at 25, 30, and 35°C, and tested daily for chlorine concentration and pH. Maximum shelf-life was defined as days until initial concentration fell to 30 days. Models were developed for solutions with maximum shelf-lives between 1–30 days. Extrapolating to 40°C, the maximum predicted shelf-life for 0.05% and 0.5% NaDCC solutions were 0.38 and 0.82 hours, respectively; predicted shelf-life for 0.05% and 0.5% generated NaOCl solutions were >30 and 5.4 days, respectively. Each chlorine solution type offers advantages and disadvantages to responders, as: NaDCC is an easy-to-import high-concentration effervescent powder; HTH is similar, but forms a precipitate that may clog pipes; and, NaOCl solutions can be made locally, but are difficult to transport. We recommend responders chose the most appropriate source chlorine compound for their use, and ensure solutions are stored at appropriate temperatures and used or replaced before expiring. PMID:27244552

  5. Ozone depletion and chlorine loading potentials

    Science.gov (United States)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  6. Electroprecipitation of potassium americyl carbonate from potassium carbonate solutions

    International Nuclear Information System (INIS)

    Precipitation of potassium americyl carbonate was carried out at multigram scale by oxidizing americium(III) at the platinum anode in 3M K2CO3 solutions. Early investigations were conducted on pure americium 241 solutions on the 10 to 40 mg scale, in order to study the different parameters of the electrolysis, and to prove the feasibility of the process. Further experiments were performed on the 20 g scale, in impure americium 241 solutions. Electrolysis performed at 600C with a platinum grid as the anode, and a tantalum rod immersed in a cathodic compartment, precipitated 20 g of americium 241 with yields above 99% in 2 h. The electroprecipitation process presents the advantage of being clean and suitable for automation techniques in comparison with the chemical oxidation process using potassium persulphate. (orig.)

  7. Electroprecipitation of potassium americyl carbonate from potassium carbonate solutions

    International Nuclear Information System (INIS)

    Precipitation of potassium americyl carbonate was carried out at multigram scale by oxidizing at platinum anode Am(III) in 3 M K2CO3 solutions. Early investigations were conducted on pure americium 241 solutions on 10 to 40 mg scale, in order to study the different parameters of the electrolysis, and to prove the faisability of the process. Further experiments have been performed on the 20 grams scale, in impure americium 241 solutions. Electrolysis performed at 600C with platinum grid as anode, and tantalum rod immersed in a cathodic compartment, precipitates 20 grams of americium 241 with yields above 99% in two hours. The electroprecipitation process presents the advantage to be clean and suitable for automation technique in comparison with the chemical oxidation process using potassium persulfate

  8. Chloride is essential for contraction of afferent arterioles after agonists and potassium

    DEFF Research Database (Denmark)

    Jensen, B L; Ellekvist, Peter; Skøtt, O

    1997-01-01

    A depolarizing chloride efflux has been suggested to activate voltage-dependent calcium channels in renal afferent arteriolar smooth muscle cells in response to vasoconstrictors. To test this proposal, rabbit afferent arterioles were microperfused, and the contractile dose responses to...... chloride. We conclude that norepinephrine and ANG II use different mechanisms for contraction and that extracellular chloride is essential for contraction in afferent arterioles after activation of voltage-dependent calcium channels. We suggest that a chloride influx pathway is activated concomitantly with......). Reintroduction of chloride fully restored the sensitivity to norepinephrine. Contractions after ANG II and potassium were totally abolished in the absence of chloride (n = 6). In additional experiments (n = 7), the arteriolar contraction to 100 mM potassium was abolished only 1 min after removal of extracellular...

  9. Radiolytic removal of trihalomethane in chlorinated seawater

    International Nuclear Information System (INIS)

    Biofouling is one of the major operational problems in seawater cooling systems. It is controlled by application of chlorine based biocides in the range of 0.5-2.0 mg L-1. The bromide in seawater reacts with the added chlorine and forms hypobromous acid. The brominated residual biocides react with natural organic matter present in the seawater, resulting in the formation of trihalomethanes (THM) such as bromoform (CHBr3), dibromochloromethane (CHBr2Cl) bromodichloromethane (CHBrCl2). Though THMs represent a small fraction of the added chlorine, they are relatively more persistent than residual chlorine, and hence pose a potential hazard to marine life because of their reported mutagenicity. There have been few reports on removal of THMs from chlorinated seawater. In this work, the efficacy of gamma irradiation technique for the removal of THMs from chlorine-dosed seawater was investigated. Experiments were carried out using seawater collected from Kalpakkam. Irradiation study was conducted in chlorinated (1, 3, and 5 mg L-1 of Cl2) seawater by applying various dosages (0.4-5.0 kGy) of gamma radiation using a 60Co Gamma Chamber 5000. Bromoform showed a faster rate of degradation as compared to other halocarbons like bromodichloromethane and dibromochloromethane. This shows the change in total THM concentration with variation in the radiation dose and initial Cl2 dosing. When the percentage degradation of all the three trihalomethane species was compared with applied doses, it was found that the maximum reduction occurred at a dose of 2.5 kGy. The reduction was almost similar for all the three doses (1, 3, 5 ppm of Cl2) used for chlorination. With a further increase in radiation dose to 5.0 kGy, a slight increase in reduction was observed

  10. Characterization of FeCo based catalyst for ammonia decomposition. The effect of potassium oxide

    Directory of Open Access Journals (Sweden)

    Lendzion-Bieluń Zofia

    2014-12-01

    Full Text Available FeCo fused catalyst was obtained by fusing iron and cobalt oxides with an addition of calcium, aluminium, and potassium oxides (CaO, Al2O3, K2O. An additional amount of potassium oxide was inserted by wet impregnation. Chemical composition of the prepared catalysts was determined with an aid of the XRF method. On the basis of XRD analysis it was found that cobalt was built into the structure of magnetite and solid solution of CoFe2O4 was formed. An increase in potassium content develops surface area of the reduced form of the catalyst, number of adsorption sites for hydrogen, and the ammonia decomposition rate. The nitriding process of the catalyst slows down the ammonia decomposition.

  11. Patterns in potassium dynamics in forest ecosystems.

    Science.gov (United States)

    Tripler, Christopher E; Kaushal, Sujay S; Likens, Gene E; Walter, M Todd

    2006-04-01

    The biotic cycling of potassium (K) in forest systems has been relatively understudied in comparison with nitrogen (N) and phosphorus (P) despite its critical roles in maintaining the nutrition of primary production in forests. We investigated the ecological significance of K in forests from a literature review and data synthesis. We focused on (1) describing patterns of the effects of K availability on aboveground growth and change in foliar tissue of tree species from a variety of forests; and (2) documenting previously unreported relationships between hydrologic losses of K and N in forested watersheds from the Americas. In a review of studies examining tree growth under K manipulations/fertilizations, a high percentage (69% of studies) showed a positive response to increases in K availability in forest soils. In addition, 76% of the tree studies reviewed showed a positive and significant increase in K concentrations in plant tissue after soil K manipulation/fertilization. A meta-analysis on a subset of the reviewed studies was found to provide further evidence that potassium effects tree growth and increased tissue [K] with an effect size of 0.709 for growth and an overall effect size of 0.56. In our review of watershed studies, we observed that concentrations of K typically decreased during growing seasons in streams draining forested areas in the Temperate Zones and were responsive to vegetation disturbance in both temperate and tropical regions. We found a strong relationship (r2 = 0.42-0.99) between concentrations of K and N (another critical plant nutrient) in stream water, suggesting that similar mechanisms of biotic retention may control the flow of these nutrients. Furthermore, K dynamics appear to be unique among the base cations, e.g. calcium, magnesium, and sodium, because the others do not show similar seasonal patterns to K. We suggest that K may be important to the productivity and sustenance of many forests, and its dynamics and ecological

  12. Synthesis, structure, and frequency-doubling effect of calcium cyanurate.

    Science.gov (United States)

    Kalmutzki, Markus; Ströbele, Markus; Wackenhut, Frank; Meixner, Alfred J; Meyer, H-Jürgen

    2014-12-15

    Calcium cyanurate is synthesized by reacting calcium chloride with potassium cyanate following a solid-state reaction. The formation of the new compound Ca3(O3C3N3)2 (CCY), which occurs by the cyclotrimerization of cyanate ions, was examined thermoanalytically and the crystal structure was determined by single-crystal structure analysis. The structure of CCY is closely related to the structure of the well-known oxoborate β-BaB2O4 (BBO). Second harmonic generation (SHG) measurements on crystal powders show a higher SHG efficiency for CCY than for BBO by about one order of magnitude. PMID:25345390

  13. Calcium in diet

    Science.gov (United States)

    ... best source. Milk and dairy products such as yogurt, cheeses, and buttermilk contain a form of calcium ... the amount of calcium in a dairy product. Yogurt, most cheeses, and buttermilk are excellent sources of ...

  14. Fenoprofen calcium overdose

    Science.gov (United States)

    Fenoprofen calcium is a type of medicine called a nonsteroidal anti-inflammatory drug. It is a prescription pain medicine used to relieve symptoms of arthritis . Fenoprofen calcium overdose occurs when someone takes more than the ...

  15. Calcium channel blocker overdose

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002580.htm Calcium channel blocker overdose To use the sharing features on this page, please enable JavaScript. Calcium channel blockers are a type of medicine used ...

  16. Fenoprofen calcium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002649.htm Fenoprofen calcium overdose To use the sharing features on this page, please enable JavaScript. Fenoprofen calcium is a type of medicine called a nonsteroidal ...

  17. Synthesis of potassium ferrate using residual ferrous sulfate as iron bearing material

    International Nuclear Information System (INIS)

    This paper summarizes the results obtained during potassium ferrate (K2FeVIO4) synthesis which is a high added value material. This compound that contains iron in the rare hexavalent state is becoming a substance of growing importance for the water and effluent treatment industries. This is due to its multi-functional nature (oxidation, flocculation, elimination of heavy metals, decomposition of organic matter, etc.). The most well known synthesis methods for potassium ferrate synthesis are those involving the chemical and/or electrochemical oxidation of iron (II) and (III) from aqueous solutions having a high alkali concentration. These methods are generally characterized by a low FeVI efficiency due to the reaction of the potassium ferrate with water, leading to the reduction of FeVI into FeIII. Concerning the work pertinent to this paper, the synthesis of K2FeVIO4 was achieved by a simultaneous reaction of two solids (iron sulfate and KOH) and one gaseous oxidant (chlorine). The synthesis process is performed in a rotary reactor at room temperature and the global synthesis reaction is exothermic. The effects of different experimental parameters on the potassium ferrate synthesis are investigated to determine the optimal conditions for the process.

  18. Photostability of different chlorine photosensitizers

    International Nuclear Information System (INIS)

    In this paper, we report the photodegradation of three different chlorine photosensitizers (Photoditazine®, Radachlorin®, and Foscan®). The photosensitizer degradation was analyzed by changes in the fluorescence spectrum during illumination. The rate of fluorescence variation was normalized to the solution absorption and the photon energy resulting in the determination of the necessary number of photons to be absorbed to induce photosensitizer photodegradation. The parameter for rate of the molecules decay, the photon fluence rate and optical properties of the solution allow us to determine the photosensitizer stability in solution during illumination. The results show that the order of susceptibility for photodegradation rate is: Radachlorin® < Photoditazine® < Foscan®. This difference in the photodegradation rate for Foscan can be explained by the high proportion of aggregates in solution that inhibit the photo-oxidative process that impede the singlet oxygen formation. We hypothesize that there is a correlation between photodegradation rate and photodynamic efficacy witch is governed by the singlet oxygen formation responsible for the most relevant reaction of the cell death photodynamic induction. Then its is important to know the photostability of different types of drugs since the photodegradation rate, the photodegradation as well as the photodynamic efficacy are strong correlated to the oxygen concentration in the tissue

  19. Chlorine Abundances in Cool Stars

    CERN Document Server

    Maas, Z G; Hinkle, K

    2016-01-01

    Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H$^{35}$Cl at 3.69851 $\\mu$m. The high resolution L-band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4m telescope. The average [$^{35}$Cl/Fe] abundance in stars with --0.72$<$[Fe/H]$<$0.20 is [$^{35}$Cl/Fe]=(--0.10$\\pm$0.15) dex. The mean difference between the [$^{35}$Cl/Fe] ratios measured in our stars and chemical evolution model values is (0.16$\\pm$0.15) dex. The [$^{35}$Cl/Ca] ratio has an offset of $\\sim$0.35 dex above model predictions suggesting chemical evolution models are under producing Cl at the high metallicity range. Abundances of C, N, O, Si, and Ca were also measured in our spectral region and are consistent with F and G dwarfs. The Cl versus O abundances from our sample match Cl abundances measured in planetary nebula and \\ion{H}{2} regions. In one star where both H$^{35}$Cl a...

  20. T-type voltage-gated calcium channels regulate the tone of mouse efferent arterioles

    DEFF Research Database (Denmark)

    Poulsen, Christian B; Al-Mashhadi, Rozh H; Cribbs, Leanne L;

    2011-01-01

    Voltage-gated calcium channels are important for the regulation of renal blood flow and the glomerular filtration rate. Excitation-contraction coupling in afferent arterioles is known to require activation of these channels and we studied their role in the regulation of cortical efferent arteriolar...... tone. We used microdissected perfused mouse efferent arterioles and found a transient vasoconstriction in response to depolarization with potassium; an effect abolished by removal of extracellular calcium. The T-type voltage-gated calcium channel antagonists mibefradil and nickel blocked this potassium....... Low concentrations of nickel, an agent that blocks Ca(v)3.2, had a similar effect. Thus, T-type voltage-gated calcium channels are functionally important for depolarization-induced vasoconstriction and subsequent dilatation in mouse cortical efferent arterioles.Kidney International advance online...

  1. Calcium and magnesium disorders.

    Science.gov (United States)

    Goff, Jesse P

    2014-07-01

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

  2. Calcium and Mitosis

    Science.gov (United States)

    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.

  3. Effects of arsenic trioxide on voltage-dependent potassium channels and on cell proliferation of human multiple myeloma cells

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jin; WANG Wei; WEI Qing-fang; FENG Tie-ming; TAN Li-jun; YANG Bao-feng

    2007-01-01

    @@ Arsenic trioxide (ATO) can induce cellular apoptosis and inhibit the activities of multiple myeloma (MM)cells in vitro,1 but how it works is not very clear. Recent studies showed that ATO worked on the voltagedependent potassium channel and L-type calcium channel in myocardial cells,2-5 but the effect of ATO on ion channels of tumor cells was rarely reported. As the potassium channel plays an important role in controlling cell proliferation,6 we studied the effects of ATO on the voltage-dependent potassium current (Ikv) of the voltage-dependent potassium channel in an MM cell line,and probed into the relationship between changes of the Ikv caused by ATO and cell proliferation.

  4. Accuracy, Precision, Ease-Of-Use, and Cost of Methods to Test Ebola-Relevant Chlorine Solutions

    Science.gov (United States)

    Wells, Emma; Wolfe, Marlene K.; Murray, Anna; Lantagne, Daniele

    2016-01-01

    To prevent transmission in Ebola Virus Disease (EVD) outbreaks, it is recommended to disinfect living things (hands and people) with 0.05% chlorine solution and non-living things (surfaces, personal protective equipment, dead bodies) with 0.5% chlorine solution. In the current West African EVD outbreak, these solutions (manufactured from calcium hypochlorite (HTH), sodium dichloroisocyanurate (NaDCC), and sodium hypochlorite (NaOCl)) have been widely used in both Ebola Treatment Unit and community settings. To ensure solution quality, testing is necessary, however test method appropriateness for these Ebola-relevant concentrations has not previously been evaluated. We identified fourteen commercially-available methods to test Ebola-relevant chlorine solution concentrations, including two titration methods, four DPD dilution methods, and six test strips. We assessed these methods by: 1) determining accuracy and precision by measuring in quintuplicate five different 0.05% and 0.5% chlorine solutions manufactured from NaDCC, HTH, and NaOCl; 2) conducting volunteer testing to assess ease-of-use; and, 3) determining costs. Accuracy was greatest in titration methods (reference-12.4% error compared to reference method), then DPD dilution methods (2.4–19% error), then test strips (5.2–48% error); precision followed this same trend. Two methods had an accuracy of Ebola-relevant chlorine solution concentrations. PMID:27243817

  5. Calcium en cardioplegie

    NARCIS (Netherlands)

    Ruigrok, T.J.C.; Meijler, F.L.

    1985-01-01

    Coronary perfusion with a calcium-free solution, followed by reperfusion with a calcium containing solution, may result in acute myocardial cell death and in irreversible loss of the e1ectrical and mechanical activity of the heart. This phenomenon is known as the calcium paradox. A number of cardiop

  6. Effects of chlorine and chlorine dioxide on human rotavirus infectivity and genome stability.

    Science.gov (United States)

    Xue, Bin; Jin, Min; Yang, Dong; Guo, Xuan; Chen, Zhaoli; Shen, Zhiqiang; Wang, Xinwei; Qiu, Zhigang; Wang, Jingfeng; Zhang, Bin; Li, Junwen

    2013-06-15

    Despite the health risks posed by waterborne human rotavirus (HRV), little information is available concerning the effectiveness of chlorine or chlorine dioxide (ClO2), two common disinfectants of public water sources, against HRV and their effects on its genome remain poorly understood. This study investigated the effects of chlorine and ClO2 on purified HRV by using cell culture and RT-PCR to assess virus infectivity and genetic integrity, respectively. The disinfection efficacy of ClO2 was found to be higher than that of chlorine. According to the efficiency factor Hom model, Ct value (mg/L min) ranges required for a 4-log reduction of HRV at 20 °C by chlorine and ClO2 were 5.55-5.59 and 1.21-2.47 mg/L min, respectively. Detection of the 11 HRV genome segments revealed that damage to the 1227-2354 bp of the VP4 gene was associated with the disappearance of viral infectivity by chlorine. However, no complete accordance between culturing and RT-PCR assays was observed after treatment of HRV with ClO2. These results collectively indicate that the current practice of chlorine disinfection may be inadequate to manage the risk of waterborne HRV infection, and offer the potential to monitor the infectivity of HRV adapting PCR-based protocols in chlorine disinfection. PMID:23591108

  7. The inhibitory effects of potassium chloride versus potassium silicate application on (137)Cs uptake by rice.

    Science.gov (United States)

    Fujimura, Shigeto; Yoshioka, Kunio; Ota, Takeshi; Ishikawa, Tetsuya; Sato, Makoto; Satou, Mutsuto

    2016-03-01

    After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company on 11 March 2011, potassium fertilizer was applied to agricultural fields in the southern Tohoku and northern Kanto regions of Japan to reduce the uptake of radiocesium by crops. In this study, we examined the effects of two types of potassium fertilizers, potassium chloride (a readily available potassium fertilizer) and potassium silicate (a slow-release potassium fertilizer), as well as a split application of potassium, on the accumulation of (137)Cs by rice plants in two pot experiments. The (137)Cs concentrations in the brown rice and in the above-ground plants were significantly lower after potassium chloride application than after potassium silicate application. The potassium ion (K(+)) concentrations in soil solutions sampled 9 and 21 d after transplanting were significantly higher for the potassium chloride application than for the potassium silicate application. The K(+) concentrations in soil solutions observed in the application of potassium silicate were similar to those in the treatment when no potassium was applied. This finding indicates that the application of potassium silicate did not sufficiently increase the available K(+) for rice plants in the soil, which led to a greater uptake of (137)Cs after the potassium silicate application than after the application of potassium chloride. The (137)Cs concentration in brown rice was higher in the split application of potassium fertilizer with the second application at the full heading stage than that without split application and the split application with the second application before heading. PMID:26773513

  8. Potassium Intake, Bioavailability, Hypertension, and Glucose Control.

    Science.gov (United States)

    Stone, Michael S; Martyn, Lisa; Weaver, Connie M

    2016-01-01

    Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60-100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health. PMID:27455317

  9. Potassium Intake, Bioavailability, Hypertension, and Glucose Control

    Directory of Open Access Journals (Sweden)

    Michael S. Stone

    2016-07-01

    Full Text Available Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+ ATPase pump. Approximately 90% of potassium consumed (60–100 mEq is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN is the leading cause of cardiovascular disease (CVD and a major financial burden ($50.6 billion to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health.

  10. Potassium Intake, Bioavailability, Hypertension, and Glucose Control

    Science.gov (United States)

    Stone, Michael S.; Martyn, Lisa; Weaver, Connie M.

    2016-01-01

    Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60–100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health. PMID:27455317

  11. Influencing factors and degradation products of antipyrine chlorination in water with free chlorine

    Institute of Scientific and Technical Information of China (English)

    Meiquan Cai; Liqiu Zhang; Fei Qi; Li Feng

    2013-01-01

    Owing to its low cost,free chlorine is one of the most common disinfectants for wastewater and drinking water treatment.However,the formation of disinfection byproducts has been found to occur after free chlorine disinfection in recent decades.Antipyrine (ANT),an anti-inflammatory analgesic,has been frequently detected in the aquatic environment.In this work.the removal efficiency of ANT by free chlorine oxidation in ultrapure water was investigated with batch experiments.The influencing factors on the removal of ANT were explored at initial concentrations of ANT from 0.04 to 0.64 mg/L,free chlorine dosage from 0.30 to 1.31 mg/L,and pH from 1.5 to 9.0.The main degradation products were identified by solid phase extraction-gas chromatography-mass spectrometry.The results showed that ANT reacted rapidly with free chlorine in ultrapure water systems and up to 90.6% removal efficiency of ANT was achieved after 25 sec (initial free chlorine 1 mg/L,ANT 0.5 mg/L,pH 7.0).Higher oxidant dosage,lower ANT initial concentration and low pH favor the ANT removal.The main degradation product in ANT chlorination was a monochlorine substitution product (4-chloro-l,2-dihydro1,5-dimethyl-2-phenyl-3H-pyrazol-3-one),which can be further chlorinated by free chlorine.In addition,the total organic carbon result indicated that ANT is difficult to be mineralized using chlorine.

  12. 3.6. Chlorination of alumina containing waste products

    International Nuclear Information System (INIS)

    Chlorination of alumina containing waste products is considered in this article. Based on conducted studies following optimal conditions of chlorination of alumina containing waste products with reducer - coal were found: temperature - 750-850 deg C, chlorination duration -1-1,5 hours, quantity of reducer - 30% and size of particles - 0,1 mm. Based on conducted studies following optimal conditions of chlorination of alumina containing waste products with reducer - natural gas were found: temperature - 650-750 deg C, chlorination duration - 2 hours, chlorine to methane ratio is 4:1 and size of particles - 0,2-0,3 mm.

  13. Accumulation of chlorinated benzenes in earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, W.N. [Patuxent Wildlife Research Center, Laurel, MD (United States)

    1996-12-31

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. They probably entered the water as leachates from chemical waste dumps and as effluents from manufacturing. Hexachlorobenzene and pentachlorobenzene are commonly present in Herring gull (Larus argentatus) eggs from the Great Lakes, and some of the isomers of trichlorobenzene and tetrachlorobenzene are occasionally detected at low concentrations. Hexachlorobenzene, which was formerly used as a fungicide, has been the most thoroughly studied chlorinated benzene, and has been detected in many species. Its use as a fungicide in the United States was canceled in 1984. Since about 1975 hexachlorobenzene has been formed mainly in the production of chlorinated solvents. It is highly persistent in the environment and some species are poisoned by hexachlorobenzene at very low chronic dietary exposures. As little as 1 ppm in the diet of mink (Mustela vison) reduced the birth weights of young, and 5 ppm in the diet of Japanese quail (Coturnix coturnix japonica) caused slight liver damage. This paper describes a long-term (26 wk) experiment relating the concentrations of chlorinated benzenes in earthworms to length of exposure and three 8 wk experiments relating concentration to the concentration in soil the soil organic matter content, and the degree of chlorination. 20 refs., 3 figs., 1 tab.

  14. Ultratrace potassium determination in plutonium oxide

    International Nuclear Information System (INIS)

    A new method improving the detection limit for potassium in plutonium oxide samples in a high acid matrix was developed. Ultratrace detection limits (sub parts per million) for potassium in plutonium oxide digestate were achieved by optimizing several instrument parameters. Using the Horiba Jobin-Yvon Ultima 2 ICP-AES spectrometer different settings and conditions were examined to improve the detection limit for potassium. The optimized parameters of 0.875 L min-1 sheath gas flow, 20/80 µm entrance/exit slit, 8 s MAX mode signal integration, and blank subtraction were able to lower the potassium reporting limit to 10 ng mL-1. (author)

  15. Separation of niobium from ferroniobium by chlorination

    International Nuclear Information System (INIS)

    Separation of niobium from ferroniobium by chlorine metallurgy were investigated. The chlorination of ferroniobium by chlorine gas was carried out under several thermodynamic conditions and the effective conditions were determined. Preliminary separation of niobium pentachloride from ferric chloride is possible by selective condensation with temperature gradient techniques. Selective reduction of ferric chloride to ferrous chloride by iron powder was done to separate niobium pentachloride by their volatility difference. Separation of niobium pentachloride from ferric chloride using organic solvent was tested. The niobium pentachloride with high purity could be separated effectively from ferroniobium chlorides by selective reduction of ferric chloride and selective dissolution of niobium pentachloride in organic solvent. A new dry process which has the possibility of industrial application is presented. (Author

  16. Investigation of molybdenum pentachloride interaction with chlorine

    International Nuclear Information System (INIS)

    In Raman spectra of molybdenum pentachloride solutions in liquid chlorine lines were recorded in case of 397, 312, 410, 217 and 180 cm-1 vibrations of ν1(A1'), ν2(A1'), ν5(E'), ν6(E') and ν8(E'') monomer (symmetry D3h) molecules of MoCl5. Interaction of molten molybdenum pentachloride with chlorine at increased (up to 6 MPa) pressures of Cl2 was studied. In Raman spectra of its vapour distillation in liquid chlorine alongside with MoCl5 lines appearance of new lines at 363 and 272 cm-1, similar in their frequency to the ones calculated for the vibrations ν1(A1g) and ν2(Eg) of MoCl6 molecules (symmetry Oh), was observed

  17. Impaired homeostatic mechanism of potassium handling after acute oral potassium load in diabetes mellitus.

    OpenAIRE

    H.J. Kim; Ahn, Y. H.; Park, C H; Kang, C M; Park, H C; Bae, H. Y.; Choi, S. D.

    1993-01-01

    Chronic stable diabetic patients (n = 6) were compared with healthy control subjects (n = 5) after acute oral intake of 50 mEq of potassium chloride (KCl) to investigate for possible derangements of homeostatic responses for acute term (3 hrs) to acute potassium load. Plasma renin activity (PRA), plasma aldosterone (PA), and transtubular potassium concentration gradient (TTKG) known as a useful semiquantative index of distal nephron potassium secretion were measured. All the baseline paramete...

  18. Calcium absorption and achlorhydria

    International Nuclear Information System (INIS)

    Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium used as the carrier. Mean calcium absorption (+/- S.D.) in the patients with achlorhydria was 0.452 +/- 0.125 for citrate and 0.042 +/- 0.021 for carbonate (P less than 0.0001). Fractional calcium absorption in the normal subjects was 0.243 +/- 0.049 for citrate and 0.225 +/- 0.108 for carbonate (not significant). Absorption of calcium from carbonate in patients with achlorhydria was significantly lower than in the normal subjects and was lower than absorption from citrate in either group; absorption from citrate in those with achlorhydria was significantly higher than in the normal subjects, as well as higher than absorption from carbonate in either group. Administration of calcium carbonate as part of a normal breakfast resulted in completely normal absorption in the achlorhydric subjects. These results indicate that calcium absorption from carbonate is impaired in achlorhydria under fasting conditions. Since achlorhydria is common in older persons, calcium carbonate may not be the ideal dietary supplement

  19. Corrosion-electrochemical behavior of nickel in an alkali metal carbonate melt under a chlorine-containing atmosphere

    OpenAIRE

    Nikitina, E. V.; Kudyakov, V. Y.; Malkov, V. B.; Plaksin, S. V.

    2013-01-01

    The corrosion-electrochemical behavior of a nickel electrode is studied in the melt of lithium, sodium, and potassium (40: 30: 30 mol %) carbonates in the temperature range 500-600°C under an oxidizing atmosphere CO2 + 0.5O2 (2: 1), which is partly replaced by gaseous chlorine (30, 50, 70%) in some experiments. In other experiments, up to 5 wt % chloride of sodium peroxide is introduced in a salt melt. A change in the gas-phase composition is shown to affect the mechanism of nickel corrosion....

  20. EXERCISE ENHANCING CALCIUM ABSORPTION MECHANISM

    OpenAIRE

    Muliani

    2013-01-01

    Calcium has important role in many biological processes therefore calcium homeostasis should be maintained. Imbalance in calcium homeostasis would affects the bone metabolism, neuromuscular function, blood coagulation, cell proliferation and signal transduction. Homeostasis of calcium is maintained by three major organs: gastrointestinal tract, bone and kidney. Intestinal calcium absorption is the sole mechanism to supply calcium to the body. Calcium absorption controlled by calcitropic hormo...

  1. Simultaneous chlorination and sulphation of calcined limestone

    Energy Technology Data Exchange (ETDEWEB)

    Matsukata, M.; Takeda, K.; Miyatain, T.; Ueyama, K. [Osaka University, Osaka (Japan). Dept. of Chemical Engineering

    1996-06-01

    In order to analyze HCl and SO{sub 2} retention in fluidized bed combustors of coal and wastes, chlorination and sulphation of calcined limestone were investigated at 1023 K and atmospheric pressure using thermogravimetry. The rate of chlorination of calcined limestone slightly depended on its particle size and was kept almost constant against the progress of chlorination. In contrast, the rate of sulphation increased with decreasing particle size and steeply decreased with the progress of sulphation as commonly reported. It was found that the sulphation was markedly accelerated in the presence of HCl. Such acceleration of sulphation was remarkable for larger limestone. The level of conversion of CaO to (CaSO{sub 4} + CaCl{sub 2}) always approached 100% in the simultaneous absorption of HCl and SO{sub 2}. It was observed by SEM that in the chlorination a number of spherical aggregates and large voids were formed on the surface of limestone and that large aggregates with very flat surface and large voids have been formed in the course of the simultaneous chlorination and sulphation. The chlorination behavior and the acceleration of SO{sub 2} absorption in the presence of HCl can be due both to the formation of a mobile Cl{sup -} ion-containing phase and to the formation of voids playing a role of the diffusion paths for HCl and SO{sub 2} toward the interior of a limestone particle. Melting of a eutectic mixture of CaCl{sub 2} and CaSO{sub 4} might largely contribute to the promotion of SO{sub 2} absorption in the case of simultaneous absorption of HCl and SO{sub 2}. 8 refs., 4 figs.

  2. Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides

    DEFF Research Database (Denmark)

    Morales-Suárez-Varela, Maria M; Olsen, Jorn; Villeneuve, Sara;

    2013-01-01

    To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF).......To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF)....

  3. The effects of low level chlorination and chlorine dioxide on biofouling control in a once-through service water system

    International Nuclear Information System (INIS)

    Continuous chlorination has been successfully used for the control of Corbicula at a nuclear power plant located on the Chattahoochee River in southeastern Alabama, since 1986. The purpose of this study was to investigate further minimization of chlorine usage and determine if chlorine dioxide is a feasible alternative. Four continuous biocide treatments were evaluated for macro and microfouling control effectiveness, operational feasibility, and environmental acceptability. One semi-continuous chlorination treatment was also evaluated for macrofouling control effectiveness. Higher treatment residuals were possible with chlorine dioxide than with chlorination due to the river discharge limitations. At the levels tested, continuous chlorine dioxide was significantly more effective in providing both macro and microfouling control. Semi-continuous chlorination was just as effective as continuous chlorination for controlling macrofouling. The Corbicula treatment programs that were tested should all provide sufficient control for zebra mussels. Chlorine dioxide was not as cost effective as chlorination for providing macrofouling control. The semi-continuous treatment save 50% on chemical usage and will allow for the simultaneous treatment of two service water systems. Chlorite levels produced during the chlorine dioxide treatments were found to be environmentally acceptable. Levels of trihalomethanes in the chlorinated service water were less than the maximum levels allowed in drinking water

  4. Review of chlorination of zirconium dioxide

    International Nuclear Information System (INIS)

    A review of chlorination zirconium dioxide is presented.used semi batch process with vertical reactor, horizontal reactor and fluidized reactor. The feed were zircon dioxide from Aldrich, direct zircon sand and briquette of zircon sand. From the study it is obtained that the best reactor is vertical reactor.It needs modification of chlorination reactor and sublimator to obtain the larger conversion. It is come to reality that zirconium tetrachloride preparation by process is significant with zirconium tetrachloride from Aldrich. It needs the sequel research to get the best result of process. (author)

  5. Chlorinated organic compounds produced by Fusarium graminearum.

    Science.gov (United States)

    Ntushelo, Khayalethu

    2016-06-01

    Fusarium graminearum, a pathogen of wheat and maize, not only reduces grain yield and degrades quality but also produces mycotoxins in the infected grain. Focus has been on mycotoxins because of the human and animal health hazards associated with them. In addition to work done on mycotoxins, chemical profiling of F. graminearum to identify other compounds produced by this fungus remains critical. With chemical profiling of F. graminearum the entire chemistry of this fungus can be understood. The focus of this work was to identify chlorinated compounds produced by F. graminearum. Various chlorinated compounds were detected and their role in F. graminearum is yet to be understood. PMID:27165533

  6. Role for voltage gated calcium channels in calcitonin gene-related peptide release in the rat trigeminovascular system

    DEFF Research Database (Denmark)

    Amrutkar, D V; Ploug, K B; Olesen, J;

    2011-01-01

    Clinical and genetic studies have suggested a role for voltage gated calcium channels (VGCCs) in the pathogenesis of migraine. Release of calcitonin gene-related peptide (CGRP) from trigeminal neurons has also been implicated in migraine. The VGCCs are located presynaptically on neurons and are...... potassium releases CGRP, and the release is regulated by Ca2+ ions and voltage-gated calcium channels....... potassium induced CGRP release. In the absence of calcium ions (Ca2+) and in the presence of a cocktail of blockers, the stimulated CGRP release from dura mater was reduced almost to the same level as basal CGRP release. In the TG ω-conotoxin GVIA inhibited the potassium induced CGRP release significantly...

  7. Role for voltage gated calcium channels in calcitonin gene-related peptide release in the rat trigeminovascular system

    DEFF Research Database (Denmark)

    Amrutkar, D V; Ploug, K B; Olesen, J;

    2011-01-01

    Clinical and genetic studies have suggested a role for voltage gated calcium channels (VGCCs) in the pathogenesis of migraine. Release of calcitonin gene-related peptide (CGRP) from trigeminal neurons has also been implicated in migraine. The VGCCs are located presynaptically on neurons and are...... potassium releases CGRP, and the release is regulated by Ca2+ ions and voltage-gated calcium channels....... potassium induced CGRP release. In the absence of calcium ions (Ca2+) and in the presence of a cocktail of blockers, the stimulated CGRP release from dura mater was reduced almost to the same level as basal CGRP release. In the TG ¿-conotoxin GVIA inhibited the potassium induced CGRP release significantly...

  8. Formulation, Characterization and Physicochemical Evaluation of Potassium Citrate Effervescent Tablets

    Directory of Open Access Journals (Sweden)

    Fatemeh Fattahi

    2013-02-01

    Full Text Available Purpose: The aim of this study was to design and formulation of potassium citrate effervescent tablet for reduction of calcium oxalate and urate kidney stones in patients suffering from kidney stones. Methods: In this study, 13 formulations were prepared from potassium citrate and effervescent base in different concentration. The flowability of powders and granules was studied. Then effervescent tablets were prepared by direct compression, fusion and wet granulation methods. The prepared tablets were evaluated for hardness, friability, effervescent time, pH, content uniformity. To amend taste of formulations, different flavoring agents were used and then panel test was done by using Latin Square method by 30 volunteers. Results: Formulations obtained from direct compression and fusion methods had good flow but low hardness. Wet granulation improves flowability and other physicochemical properties such as acceptable hardness, effervescence time ≤3 minutes, pH<6, friability < 1%, water percentage < 0.5% and accurate content uniformity. In panel test, both of combination flavors; (orange - lemon and (strawberry - raspberry had good acceptability. Conclusion: The prepared tablets by wet granulation method using PVP solution had more tablet hardness. It is a reproducible process and suitable to produce granules that are compressed into effervescent tablets due to larger agglomerates.

  9. Electronic properties, doping and defects in chlorinated silicon nanocrystals

    OpenAIRE

    de Carvalho, A.; Öberg, S; Rayson, M. J.; Briddon, P. R.

    2011-01-01

    Silicon nanocrystals with diameters between 1 and 3 nm and surfaces passivated by chlorine or a mixture of chlorine and hydrogen were modeled using density functional theory, and their properties compared with those of fully hydrogenated nanocrystals. It is found that fully and partially chlorinated nanocrystals are stable, and have higher electron affinity, higher ionization energy and lower optical absorption energy threshold. As the hydrogenated silicon nanocrystals, chlorinated silicon na...

  10. Attacks of Asthma due to Chlorinized Water: Case Report

    OpenAIRE

    Murat Eyup Berdan; Ercan Gocgeldi; Sami Ozturk; Ali Kutlu

    2008-01-01

    The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure ...

  11. Immunofluorescence and morphology of Giardia lamblia cysts exposed to chlorine.

    OpenAIRE

    Sauch, J F; Berman, D

    1991-01-01

    Giardia cyst-like objects detected by immunofluorescence in chlorinated water samples often cannot be positively identified by their morphological appearance. To determine the effect of chlorine on cyst immunofluorescence and morphology, Giardia lamblia cysts were exposed to chlorine for 48 h. The majority of cysts exposed to chlorine concentrations of 1 to 11 mg/liter at 5 and 15 degrees C lost their internal morphological characteristics necessary for identification, but most of them were s...

  12. Potassium conductance and oscillatory contractions in tail arteries from genetically hypertensive rats.

    Science.gov (United States)

    Lamb, F S; Webb, R C

    1989-06-01

    Tail arteries isolated from the stroke-prone substrain of the spontaneously hypertensive rat (SHR-SP) exhibit oscillatory contractile responses to norepinephrine. Simultaneous recording of force generation and membrane potential (Em) has previously demonstrated that the contractile phase of these oscillations is associated with bursts of calcium-dependent action potentials. The smooth muscle cells are electrically quiescent during the relaxation phase of the oscillations. The present studies were designed to test the hypothesis that this quiescent period results from the stimulation of a calcium-activated potassium conductance (gKCa) in the cells responsible for triggering the bursting activity. Isolated tail artery strips from SHR-SP and Wistar-Kyoto rats (WKY) were prepared for measurement of isometric force generation or for simultaneous recording of force and Em. The channel-specific toxins apamin (4 x 10(-7) mol/l) and charybdotoxin (4.7 x 10(-8) did not alter the oscillatory pattern of contraction in response to norepinephrine. Oscillations were converted to sustained contraction by barium (10(-4) mmol), quinidine (5.8 x 10(-5) mmol) and elevation of extracellular potassium (20 mmol/l). Em recordings show that both potassium and barium convert bursting activity into tonic firing. Only 20 mmol/k+ caused significant depolarization in addition to that produced by norepinephrine. In contrast, quinidine appears to alter oscillatory behavior by interfering with calcium-spike generation. Norepinephrine-induced electrical activity is diminished in the presence of quinidine. These results suggest that potassium conductance plays an important role in controlling Em, electrical spiking and therefore oscillatory contractile activity in response to norepinephrine in the tail arteries of SHR-SP.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2778313

  13. Extraction of potassium from K-feldspar via the CaCl2 calcination route☆

    Institute of Scientific and Technical Information of China (English)

    Bo Yuan; Chun Li; Bin Liang; Li Lü; Hairong Yue; Haoyi Sheng; Longpo Ye; Heping Xie

    2015-01-01

    The extraction of potassium from K-feldspar via a calcium chloride calcination route was studied with a focus on the effects of the calcination atmosphere, calcination temperature and time, mass ratio of CaCl2 to K-feldspar ore and particle size of the K-feldspar ore. The results demonstrated that a competing high-temperature hydrolysis reaction of calcium chloride with moisture in a damp atmosphere occurred concurrently with the conversion reaction of K-feldspar with CaCl2, thus reducing the amount of potassium extracted. The conversion reaction started at approximately 600 °C and accelerated with increasing temperature. When the temperature rose above 900 °C, the extraction of potassium gradually decreased due to the volatilization of the product, KCl. As much as approximately 41%of the potassium was volatilized in 40 min at 1100 °C. The mass ratio of CaCl2/K-feldspar ore significantly affected the extraction. At a mass ratio of 1.15 and 900 °C, the potassium extraction reached 91%in 40 min, while the extraction was reduced to only 22%at the theoretical mass ratio of 0.2. Optimal process conditions are as follows:ore particle size of 50–75μm, tablet forming pressure of 3 MPa, dry nitrogen atmosphere, mass ratio of CaCl2/ore 1.15:1, calcination temperature of 900 °C, and calcination time of 40 min. The XRD analysis revealed that a complex phase transition of the product SiO2 was also accompanied by the con-version reaction of K-feldspar/CaCl2. The SiO2 product formed at the initial stage was in the quartz phase at 900 °C and was gradually transformed into cristobalite after 30 min.

  14. Preventive dietary potassium supplementation in young salt-sensitive Dahl rats attenuates development of salt hypertension by decreasing sympathetic vasoconstriction

    Czech Academy of Sciences Publication Activity Database

    Zicha, Josef; Dobešová, Zdenka; Behuliak, Michal; Kuneš, Jaroslav; Vaněčková, Ivana

    2011-01-01

    Roč. 202, č. 1 (2011), s. 29-38. ISSN 1748-1708 R&D Projects: GA ČR(CZ) GA305/08/0139; GA ČR(CZ) GA305/09/0336; GA AV ČR(CZ) IAA500110902; GA MŠk(CZ) 1M0510 Institutional research plan: CEZ:AV0Z50110509 Keywords : dietary potassium * nitric oxide * prostacyclin * calcium-activated potassium channels Subject RIV: ED - Physiology Impact factor: 3.090, year: 2011

  15. Chlorine Gas: An Evolving Hazardous Material Threat and Unconventional Weapon

    Directory of Open Access Journals (Sweden)

    Jones, Robert MD

    2010-05-01

    Full Text Available Chlorine gas represents a hazardous material threat from industrial accidents and as a terrorist weapon. This review will summarize recent events involving chlorine disasters and its use by terrorists, discuss pre-hospital considerations and suggest strategies for the initial management for acute chlorine exposure events. [West J Emerg Med. 2010; 11(2:151-156.

  16. Blends of caprolactam/caprolactone copolymers and chlorinated polymers

    NARCIS (Netherlands)

    Alberda van Ekenstein, G.O.R.; Deuring, H.; ten Brinke, G.; Ellis, T.S.

    1997-01-01

    The phase behaviour of blends of chlorinated polyethylene, polyvinyl chloride (PVC) and chlorinated PVC with random copolymers of caprolactone and caprolactam has been investigated and the results correlated with a binary interaction model. The known miscibility of polycaprolactone in the chlorinate

  17. Dengue and Calcium

    OpenAIRE

    Shivanthan, Mitrakrishnan C; Rajapakse, Senaka

    2014-01-01

    Dengue is potentially fatal unless managed appropriately. No specific treatment is available and the mainstay of treatment is fluid management with careful monitoring, organ support, and correction of metabolic derangement. Evidence with regards to the role of calcium homeostasis in dengue is limited. Low blood calcium levels have been demonstrated in dengue infection and hypocalcemia maybe more pronounced in more severe forms. The cause of hypocalcemia is likely to be multifactorial. Calcium...

  18. Measurements of intracellular calcium

    International Nuclear Information System (INIS)

    Intracellular calcium concentration ([Ca2+]i) has been measured in cultured cells by using Fura-2 load cells and a computer-controlled Perkin Elmer LS-5B spectrofluorometer. Increased [Ca2+]i in cells exposed to extracellular bilirubin was observed both with and without extracellular calcium. However, the increase was considerable larger with extracellular calcium. The enhancement of [Ca2+]i became smaller with decreasing bilirubin/BSA (bovine serum albumine) ratio. 5 refs., 5 figs

  19. Effects of ATP on calcium binding to synaptic plasma membrane

    International Nuclear Information System (INIS)

    The release of labeled norepinephrine from preloaded synaptosomes requires the presence of potassium and calcium. ATP-dependent binding of calcium to synaptic plasma membranes (SPM) may provide a means of maintaining the cation in a readily available pool for the triggering of transmitter release. A high Ca-binding capacity was demonstrated in SPM. The Km for calcium is 5.5 X 10(-5) M. The dependence of the system on the gamma phosphate of ATP was demonstrated by an increase in Ca-binding with increasing ATP concentration and by competitive inhibition of binding by ADP and AMP. Magnesium is also required for ATP-dependent Ca-binding. The optimum pH for the Ca binding was 7.0. Pretreatment of SPM with phospholipase A2 lowered the binding capacity. Sulfhydryl groups are also critical for ATP-dependent Ca binding to occur. A model for ATP-dependent Ca-binding was proposed

  20. Evidence for Perchlorates and the Origin of Chlorinated Hydrocarbons Detected by SAM at the Rocknest Aeolian Deposit in Gale Crater

    Science.gov (United States)

    Glavin, Daniel P.; Freissinet, Caroline; Miller, Kristen E.; Eigenbrode, Jennifer L.; Brunner, Anna E.; Buch, Arnaud; Sutter, Brad; Archer, P. Douglas, Jr.; Atreya, Sushil K.; Brinckerhoff, William B.; Cabane, Michel; Coll, Patrice; Conrad, Pamela G.; Coscia, David; Dworkin, Jason P.; Franz, Heather B.; Grotzinger, John P.; Leshin, Laurie A.; Martin, Mildred G.; McKay, Christopher; Ming, Douglas W.; Navarro-Gonzalez, Rafael; Pavlov, Alexander; Steele, Andrew; Summons, Roger E.; Szopa, Cyril; Teinturier, Samuel; Mahaffy, Paul R.

    2013-01-01

    A single scoop of the Rocknest aeolian deposit was sieved (less than 150 micrometers), and four separate sample portions, each with a mass of approximately 50 mg, were delivered to individual cups inside the Sample Analysis at Mars (SAM) instrument by the Mars Science Laboratory rover's sample acquisition system. The samples were analyzed separately by the SAM pyrolysis evolved gas and gas chromatograph mass spectrometer analysis modes. Several chlorinated hydrocarbons including chloromethane, dichloromethane, trichloromethane, a chloromethylpropene, and chlorobenzene were identified by SAM above background levels with abundances of approximately 0.01 to 2.3 nmol. The evolution of the chloromethanes observed during pyrolysis is coincident with the increase in O2 released from the Rocknest sample and the decomposition of a product of N-methyl-N-(tert-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA), a chemical whose vapors were released from a derivatization cup inside SAM. The best candidate for the oxychlorine compounds in Rocknest is a hydrated calcium perchlorate (Ca(ClO4)2·nH2O), based on the temperature release of O2 that correlates with the release of the chlorinated hydrocarbons measured by SAM, although other chlorine-bearing phases are being considered. Laboratory analog experiments suggest that the reaction of Martian chlorine from perchlorate decomposition with terrestrial organic carbon from MTBSTFA during pyrolysis can explain the presence of three chloromethanes and a chloromethylpropene detected by SAM. Chlorobenzene may be attributed to reactions of Martian chlorine released during pyrolysis with terrestrial benzene or toluene derived from 2,6-diphenylphenylene oxide (Tenax) on the SAM hydrocarbon trap. At this time we do not have definitive evidence to support a nonterrestrial carbon source for these chlorinated hydrocarbons, nor do we exclude the possibility that future SAM analyses will reveal the presence of organic compounds native to the

  1. Rare, severe hypersensitivity reaction to potassium iodide

    DEFF Research Database (Denmark)

    Nielsen, Anne Sofie Korsholm; Ebbehøj, Eva; Richelsen, Bjørn

    2014-01-01

    The literature reports a large variety of adverse reactions to potassium iodide. A severe hypersensitivity reaction to potassium iodide in a 51-year-old woman with Graves' thyrotoxicosis is described. Following administration the patient developed sialadenitis, conjunctivitis, stomatitis and acne...

  2. Neutron diffraction studies of potassium thiocyanate

    International Nuclear Information System (INIS)

    Measurements of some low frequency phonon dispersion curves in potassium thiocyanate have been made using inelastic neutron scattering techniques. Elastic neutron powder diffraction measurements have also been made on potassium thiocyanate to resolve discrepancies in the literature concerning its structure. (author) 11 refs., 6 figs., 1 tab

  3. 21 CFR 184.1643 - Potassium sulfate.

    Science.gov (United States)

    2010-04-01

    ... hydroxide or potassium carbonate. (b) The ingredient meets the specifications of the “Food Chemicals Codex... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium sulfate. 184.1643 Section 184.1643 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

  4. Status of potassium permanganate label claim - 2007

    Science.gov (United States)

    A brief overview of the Technical Sections completed and being worked on for the New Animal Drug Application (NADA) for potassium permanganate will be presented. Various aspects of these technical sections will be open for discussion. Potassium Permanganate Initial Label Claim (Columnaris on cat...

  5. 75 FR 23298 - Potassium Permanganate From China

    Science.gov (United States)

    2010-05-03

    ... potassium permanganate from China (70 FR 35630). The Commission is now conducting a third review to... permanganate from China (64 FR 66166). Following second five-year reviews by Commerce and the Commission... COMMISSION Potassium Permanganate From China AGENCY: United States International Trade Commission....

  6. Calcium pretreatment increases thermotolerance of Laminaria japonica sporophytes

    Institute of Scientific and Technical Information of China (English)

    You Wang; Qingyun Yu; Xuexi Tang; Lili Wang

    2009-01-01

    Calcium is a secondary messenger in plant signaling,and its concentration changes spatially and temporally during the course of heat stress.In the present study,potassium antimonate was used to visualize calcium localization in blades of a marine macroalga,the juvenile Laminariajaponica sporophytes under heat stress (25 ℃).Result showed that loosely bound calcium was mainly distributed on the cell wall under normal conditions (10 ℃),and flowed into the cytoplasm when exposed to heat.The simutaneous assay on the antioxidant system changes was performed.Oxidative damage,as measured by generation of reactive oxygen species (ROS) malondialdehyde (MDA) content,increased significantly during heat stress,and calcium pretreatment alleviated oxidative damage.The assay on the activities of six antioxidant enzymes demonstrated that their enzymatic activities were inhibited when exposed to heat stress,but Ca2+ pretreatment effectively attenuated the inhibition.Results in the present study inferred that calcium homeostasis plays an essential role in L.japonica sporophyte when exposed to heat,and calcium pretreatment could improve its thermo-tolerance.

  7. 46 CFR 151.50-31 - Chlorine.

    Science.gov (United States)

    2010-10-01

    ... desired rate of discharge, provided the air or gas is oil-free and thoroughly dried by passing it over activated aluminum oxide, silica gel, or other acceptable drying agent, and provided the supply pressure is...-resistant to chlorine in either the gas or liquid phase. Cast or malleable iron shall not be used....

  8. Chlorinated tyrosine derivatives in insect cuticle

    DEFF Research Database (Denmark)

    Andersen, Svend Olav

    2004-01-01

    , not-yet sclerotized cuticle of adult femur and tibia, the amounts increased rapidly during the first 24 h after ecdysis and more slowly during the next two weeks. Control analyses using stable isotope dilution mass spectrometry have confirmed that the chlorinated tyrosines are not artifacts formed...

  9. Chlorinated organic compounds in urban river sediments

    Energy Technology Data Exchange (ETDEWEB)

    Soma, Y.; Shiraishi, H.; Inaba, K. [National Inst. of Environmental Studies, Tsukuba, Ibaraki (Japan)

    1995-12-31

    Among anthropogenic chemicals, many chlorinated organic compounds have been used as insecticides and detected frequently as contaminants in urban river sediments so far. However, the number and total amount of chemicals produced commercially and used are increasing year by year, though each amount of chemicals is not so high. New types of contaminants in the environment may be detected by the use of newly developed chemicals. Chlorinated organic compounds in the urban river sediments around Tokyo and Kyoto, large cities in Japan, were surveyed and recent trends of contaminants were studied. Contaminants of the river sediments in industrial areas had a variety, but PCB (polychlorinated biphenyls) was detected in common in industrial areas. Concentration of PCB related well to the number of factories on both sides of rivers, although the use of PCB was stopped 20 years ago. In domestic areas, Triclosan (5-chloro-2-(2,4-dichlorophenoxy)-phenol) and Triclocarban (3,4,4{prime}-trichlorocarbanilide)(both are contained in soap or shampoo for fungicides), p-dichlorobenzene (insecticides for wears) and TCEP(tris-chloroethyl phosphate) were detected. EOX(extracted organic halogen) in the sediments was 5 to 10 times of chlorinated organic compounds detected by GC/MS. Major part of organic halogen was suggested to be included in chlorinated organics formed by bleaching or sterilization.

  10. Anaerobic biodegradability and toxicity of wastewaters from chlorine and total chlorine-free bleaching of eucalyptus kraft pulps.

    NARCIS (Netherlands)

    Vidal, G.; Soto, M.; Field, J.; Mendez-Pampin, R.; Lema, J.M.

    1997-01-01

    Chlorine bleaching effluents are problematic for anaerobic wastewater treatment due to their high methanogenic toxicity and low biodegradability. Presently, alternative bleaching processes are being introduced, such as elemental chlorine-free (ECF) and total chlorine-free (TCF) bleaching. The methan

  11. Cellular Response of the Amoeba Acanthamoeba castellanii to Chlorine, Chlorine Dioxide, and Monochloramine Treatments ▿

    OpenAIRE

    Mogoa, Emerancienne; Bodet, Charles; Morel, Franck; Rodier, Marie-Hélène; Legube, Bernard; Héchard, Yann

    2011-01-01

    Acanthamoeba castellanii is a free-living amoebae commonly found in water systems. Free-living amoebae might be pathogenic but are also known to bear phagocytosis-resistant bacteria, protecting these bacteria from water treatments. The mode of action of these treatments is poorly understood, particularly on amoebae. It is important to examine the action of these treatments on amoebae in order to improve them. The cellular response to chlorine, chlorine dioxide, and monochloramine was tested o...

  12. A survey of Io's potassium cloud

    Science.gov (United States)

    Trafton, L.

    1981-08-01

    Io's potassium cloud exhibits spatial and temporal variations similar to those observed for Io's sodium cloud. Spectra from five apparitions show that the potassium cloud is elongated so that it extends forward from Io's leading, inner hemisphere and makes an angle with Io's orbit of 10-30 deg, slightly less than the angle for the sodium cloud. The potassium cloud is a long-lived phenomenon which undergoes periodic fluctuations in response to solar radiation pressure and the ionizing influence of Jupiter's plasma torus. These give rise to east-west and north-south asymmetry variations similar to those observed for the sodium cloud. Evidence for temporary jets of potassium streaming from Io have also been observed. These similarities with the sodium cloud suggest that both sodium and potassium are ejected from nearly the same regions of Io by the same physical mechanism.

  13. Extracellular potassium inhibits Kv7.1 potassium channels by stabilizing an inactivated state

    DEFF Research Database (Denmark)

    Larsen, Anders Peter; Steffensen, Annette Buur; Grunnet, Morten; Olesen, Søren-Peter

    2011-01-01

    Kv7.1 (KCNQ1) channels are regulators of several physiological processes including vasodilatation, repolarization of cardiomyocytes, and control of secretory processes. A number of Kv7.1 pore mutants are sensitive to extracellular potassium. We hypothesized that extracellular potassium also...... modulates wild-type Kv7.1 channels. The Kv7.1 currents were measured in Xenopus laevis oocytes at different concentrations of extracellular potassium (1-50 mM). As extracellular potassium was elevated, Kv7.1 currents were reduced significantly more than expected from theoretical calculations based on the...... Goldman-Hodgkin-Katz flux equation. Potassium inhibited the steady-state current with an IC(50) of 6.0 ± 0.2 mM. Analysis of tail-currents showed that potassium increased the fraction of channels in the inactivated state. Similarly, the recovery from inactivation was slowed by potassium, suggesting that...

  14. SYNTHESIS OF POTASSIUM FERRATE FOR USE IN TEXTILE WASTEWATER TREATMENT

    Directory of Open Access Journals (Sweden)

    F. Vaezi

    1999-12-01

    Full Text Available Potassium ferrate has been used as a multi-purpose chemical in treatment of wastewaters. With the formula of K2Fe04 it has 3 excellent characters for water treatment, so by using it alone, it would be possible to confine all reactivity, it is essential to prepare ferrate at the point of use. In this study, K2Fe04 was synthesized, then it has been employed for chlorine gas with an alkaline solution of ferric chloride, then it has been employed for textile wastewater treatment. Textile is one of the industries with high significance for water pollution. Comparison of results with a conventional coagulant (FeC13 has shown that total COD and SS removal were about 27 to 29 and 0.7 to 2 percent more and the sludge volume was 2.5 times less, also, the required dose of K2Fe04 for this treatment. Another advantage of using ferrate is its ability in reducing bacterial content of wastewater. All the simplex treated by synthesized chemical was well disinfected.

  15. Participação da excreção renal de cálcio, fósforo, sódio e potássio na homeostase em cães sadios e cães com doença renal crônica Participation of renal excretion of calcium, phosphorus, sodium and potassium on the homeostasis in healthy dogs and in dogs with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Pedro P Martínez

    2010-10-01

    serum profile of calcium, phosphorus, sodium and potassium in healthy dogs and in dogs with naturally acquired CKD. Three groups of adult male and female dogs of varied breeds were evaluated. Normal dogs were in the control group (G1 and the CKD dogs were distributed into two groups in accordance with the stage of renal function impairment (G2 e G3, respectively, stages 1-2 and stages 3-4, proposed by IRIS 2006 staging CKD. The G3 dogs showed increased serum levels of ionized calcium and phosphorus, in addition to the reduction of sodium levels. Regarding the renal excretion of the analyzed electrolytes, the G1 and G2 groups showed a decrease of filtered load and increase of fractional excretion, yet there were no significant variations on the urinary excretions. The results suggest that the kidneys of the CKD dogs can maintain similar values of electrolytes urinary excretion as the kidneys of normal dogs. The mechanism involves an increase of fractional excretion while glomerular filtration decreases. This compensation process, however, can lose its efficiency in the later stages of the disease, in relation to the maintenance of phosphorus and sodium serum levels.

  16. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    Science.gov (United States)

    Jorgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne; Civitelli, Roberto; Sorensen, Ole Helmer; Steinberg, Thomas H.

    2003-01-01

    The propagation of mechanically induced intercellular calcium waves (ICW) among osteoblastic cells occurs both by activation of P2Y (purinergic) receptors by extracellular nucleotides, resulting in "fast" ICW, and by gap junctional communication in cells that express connexin43 (Cx43), resulting in "slow" ICW. Human osteoblastic cells transmit intercellular calcium signals by both of these mechanisms. In the current studies we have examined the mechanism of slow gap junction-dependent ICW in osteoblastic cells. In ROS rat osteoblastic cells, gap junction-dependent ICW were inhibited by removal of extracellular calcium, plasma membrane depolarization by high extracellular potassium, and the L-type voltage-operated calcium channel inhibitor, nifedipine. In contrast, all these treatments enhanced the spread of P2 receptor-mediated ICW in UMR rat osteoblastic cells. Using UMR cells transfected to express Cx43 (UMR/Cx43) we confirmed that nifedipine sensitivity of ICW required Cx43 expression. In human osteoblastic cells, gap junction-dependent ICW also required activation of L-type calcium channels and influx of extracellular calcium.

  17. Reaction products of aquatic humic substances with chlorine.

    OpenAIRE

    Johnson, J D; Christman, R F; Norwood, D L; Millington, D S

    1982-01-01

    A major concern of the chlorination of aquatic humic materials is the ubiquitous production of trihalomethanes. A large number of other chlorinated organic compounds, however, have been shown to be formed by chlorine's reaction with humic substances. In this study, humic material was concentrated from a coastal North Carolina lake and chlorinated at a chlorine to carbon mole ratio of 1.5 at pH 12. A high pH was necessary for complete dissolution of the humic material and for production of ade...

  18. Calculation of potassium critical temperature

    International Nuclear Information System (INIS)

    The paper describes the algorithm of the functional prediction which is based on the selforganization of nonlinear algebraic models. The calculation procedure includes the module for the recognition of the dependence type hitch allows to restrict the number of choice of the prediction functions at the each step of the model building. The characteristic property of this algorithm is bootstrap method application as the external criteria of the selforganization. The calculation module is built using APL*PLUS and the user-friendly interface is implemented using Clipper 5.01 under Windows control. When using the algorithm and the programs, the critical point of potassium has been predicted on the base of the solubility curves of liquid and steam. 9 refs.; 1 fig.; 1 tab

  19. Serum Calcium Level in Hypertension

    OpenAIRE

    Hazari, Mohammed Abdul Hannan; Arifuddin, Mehnaaz Sameera; Muzzakar, Syed; Reddy, Vontela Devender

    2012-01-01

    Background: The alterations in extracellular calcium level may influence intracellular calcium level and possibly play a role in the pathogenesis of essential hypertension. Aim: The purpose was to find out the association between serum calcium levels and hypertension; and to compare the serum calcium levels between normotensive controls, hypertensive subjects on calcium channel blockers, and hypertensive subjects on antihypertensive medication other than calcium channel blockers. Materials an...

  20. The secretory response of parathyroid hormone to acute hypocalcemia in vivo is independent of parathyroid glandular sodium/potassium-ATPase activity

    DEFF Research Database (Denmark)

    Martuseviciene, Giedre; Hofman-Bang, Jacob; Clausen, Torben; Olgaard, Klaus; Lewin, Ewa

    2011-01-01

    The involvement of sodium/potassium-ATPase in regulating parathyroid hormone (PTH) secretion is inferred from in vitro studies. Recently, the α-klotho-dependent rapid recruitment of this ATPase to the parathyroid cell plasma membrane in response to low extracellular calcium ion was suggested to be...

  1. Survival and Heat Resistance of Listeria monocytogenes after Exposure to Alkali and Chlorine

    Science.gov (United States)

    Taormina, P. J.; Beuchat, L. R.

    2001-01-01

    A strain of Listeria monocytogenes isolated from a drain in a food-processing plant was demonstrated, by determination of D values, to be more resistant to the lethal effect of heat at 56 or 59°C following incubation for 45 min in tryptose phosphate broth (TPB) at pH 12.0 than to that of incubation for the same time in TPB at pH 7.3. Cells survived for at least 6 days when they were suspended in TPB at pHs 9.0, 10.0, and 11.0 and stored at 4 or 21°C. Cells of L. monocytogenes incubated at 37°C for 45 min and then stored for 48 or 144 h in TPB at pH 10.0 were more resistant to heat treatment at 56°C than were cells stored in TPB at pH 7.3. The alkaline-stress response in L. monocytogenes may induce resistance to otherwise lethal thermal-processing conditions. Treatment of cells in 0.05 M potassium phosphate buffer (pH 7.00 ± 0.05) containing 2.0 or 2.4 mg of free chlorine per liter reduced populations by as much as 1.3 log10 CFU/ml, while treatment with 6.0 mg of free chlorine per liter reduced populations by as much as 4.02 log10 CFU/ml. Remaining subpopulations of chlorine-treated cells exhibited some injury, and cells treated with chlorine for 10 min were more sensitive to heating at 56°C than cells treated for 5 min. Contamination of foods by L. monocytogenes cells that have survived exposure to processing environments ineffectively cleaned or sanitized with alkaline detergents or disinfectants may have more severe implications than previously recognized. Alkaline-pH-induced cross-protection of L. monocytogenes against heat has the potential to enhance survival in minimally processed as well as in heat-and-serve foods and in foods on holding tables, in food service facilities, and in the home. Cells surviving exposure to chlorine, in contrast, are more sensitive to heat; thus, the effectiveness of thermal processing in achieving desired log10-unit reductions is not compromised in these cells. PMID:11375163

  2. Relation between chlorine with the quality of crude water

    International Nuclear Information System (INIS)

    Chlorine as disinfection agent in drinking water was used widely since it was successfully been practiced in drinking water in Jersey City, 1908. Mostly, water treatment plants in Malaysia were using chlorine as disinfection agent to kill pathogen and contaminated materials that can be dangerous to consumer. Because of chlorine was a strongly disinfection agent, it also can react with another chemical components such as manganese, hydrogen, sulfides, ammonia and phenol in water. These reactions happen very fast, and chlorine will not react as disinfection agent unless all the organic and inorganic substitution presented in water reacts with chlorine. These reactions between components will increase demand of chlorine in water. The demand of chlorine in water must be filled before the free radical chlorine occurred. These free radical chlorine will decay into hypochlorous acid and hypochlorite ion that so important in disinfection process to kill pathogens and pollutants in water. Most of water treatment plant to maintain free chlorine up to 0.2 mg/ L in distribution system to consumer. These researches involved determination of parameters that can be trusted to react with the chlorine in nine sampling station along Semenyih River and four stations in water treatment plants. These parameters were determined from ammonia, cyanides, sulfides, phenol, phosphorus, nitrite, manganese, iron and sum of organic carbons. Overall, these researches concluded that ammonia and sum of organic carbons were the most compounds that react with the chlorine to produce tryhalometane and chloramines. Besides that, the concentration of cyanides compounds, sulfide, phenol, phosphorus, nitrite, manganese and iron also decrease after the chlorination process. Results can used to evaluate demanding levels of chlorine in Semenyih River. (author)

  3. VKCDB: Voltage-gated potassium channel database

    Directory of Open Access Journals (Sweden)

    Gallin Warren J

    2004-01-01

    Full Text Available Abstract Background The family of voltage-gated potassium channels comprises a functionally diverse group of membrane proteins. They help maintain and regulate the potassium ion-based component of the membrane potential and are thus central to many critical physiological processes. VKCDB (Voltage-gated potassium [K] Channel DataBase is a database of structural and functional data on these channels. It is designed as a resource for research on the molecular basis of voltage-gated potassium channel function. Description Voltage-gated potassium channel sequences were identified by using BLASTP to search GENBANK and SWISSPROT. Annotations for all voltage-gated potassium channels were selectively parsed and integrated into VKCDB. Electrophysiological and pharmacological data for the channels were collected from published journal articles. Transmembrane domain predictions by TMHMM and PHD are included for each VKCDB entry. Multiple sequence alignments of conserved domains of channels of the four Kv families and the KCNQ family are also included. Currently VKCDB contains 346 channel entries. It can be browsed and searched using a set of functionally relevant categories. Protein sequences can also be searched using a local BLAST engine. Conclusions VKCDB is a resource for comparative studies of voltage-gated potassium channels. The methods used to construct VKCDB are general; they can be used to create specialized databases for other protein families. VKCDB is accessible at http://vkcdb.biology.ualberta.ca.

  4. HYPERTHERMIA, INTRACELLULAR FREE CALCIUM AND CALCIUM IONOPHORES

    NARCIS (Netherlands)

    STEGE, GJJ; WIERENGA, PK; KAMPINGA, HH; KONINGS, AWT

    1993-01-01

    It is shown that heat-induced increase of intracellular calcium does not correlate with hyperthermic cell killing. Six different cell lines were investigated; in four (EAT, HeLa S3, L5178Y-R and L5178Y-S) heat treatments killing 90% of the cells did not affect the levels of intracellular free calciu

  5. Antiradiation effectiveness of the chlorine C

    International Nuclear Information System (INIS)

    At present ever more attention of the experimenters in the field of search of high-effective antiray means - is directed to development of preparations from bio-active substances of a natural origin. In this connection all greater interest is caused by researches of antiray activity of these compounds, distinguished, as a rule, from known preparations of synthetic manufacture of low toxicity, absence of expressed collateral effects and possibility of course application. It has biological (antiray) activity in dozes 5-10 mg/kg and chlorine C which is derivative of chlorophil A. At present it passes tests in oncology. Porphyrines (synthetic and natural) are recently subjected to wide study as potential medicinal means, due to their ability to be accumulated in bodies of the reticulo-endothelial system and proliferous tissues, as well as their physical-chemical characteristics (fluorescence, photosensitizing action, colouring). All this testifies for the benefit of perspective use of porphyrin for treatment and diagnostics of tumors. According to the above described properties of porphyrines there is that fact, that for some of them radioprotective properties are revealed during the injections as well as before and after radiation treatment. The above said has formed the basis for study of antiray properties of the chlorine C during the experiments on small-sized laboratory animals. Antiradiation effectivity of chlorine C was studied on the mice (CBA x C57 B1) F1. Chlorine C was applied in a wide range of dozes with its' use in 3 variants: before radiation treatment, after radiation treatment, combined (before and after radiation treatment). Radioprotective activity of chlorine C reduces at an increase of a time of the injection before radiation treatment and at other ways of injection (intramuscularly, subcutaneously, per os). Studies of medical activity of chlorine C in experiments on mice have shown, that the compound does not possess medical activity. The death of

  6. Extração simultânea de alumínio, cálcio, magnésio, potássio e sódio do solo com solução de cloreto de amônio Simultaneous extraction of aluminum, calcium, magnesium, potassium, and sodium with ammonium chloride solution

    Directory of Open Access Journals (Sweden)

    R. C. Boeira

    2004-10-01

    Full Text Available Atualmente, alguns laboratórios de análise de solo determinam Al, Ca e Mg trocáveis em extratos de KCl 1 mol L-1 e K e Na na solução extratora Mehlich-1, também usada na extração de fósforo. Outros laboratórios, que empregam a resina trocadora de ânions para P, avaliam também Ca, Mg e K no extrato, não sendo possível determinar Al e Na. Dessa forma, achou-se oportuno avaliar a extração com NH4Cl 1 mol L-1 na determinação simultânea dos cinco cátions trocáveis: Al, Ca, Mg, K e Na, em comparação aos extratores KCl e Mehlich-1. Utilizaram-se amostras coletadas em áreas de cultivo de fruteiras irrigadas da região Nordeste e na área experimental da Embrapa Meio Ambiente em Jaguariúna (SP. Os métodos utilizados foram: (a extração simultânea dos cinco cátions com NH4Cl 1 mol L-1, e (b extração de Ca, Mg e Al com KCl 1 mol L-1, e de K e Na com o extrator Mehlich-1. A solução de NH4Cl 1 mol L-1 apresentou maior capacidade de extração de Mg do solo do que a solução de KCl 1 mol L-1; as duas soluções se equivaleram quanto à capacidade de extração de Ca e de Al. A solução de NH4Cl extraiu mais K e Na do que a solução Mehlich-1. Conclui-se que a solução de NH4Cl é uma opção conveniente para a extração de Al, Ca, Mg, K e Na trocáveis do solo.Currently, part of the soil testing laboratories of Brazil determine exchangeable Al, Ca, and Mg in a 1 mol L-1 KCl soil extract and exchangeable sodium and potassium in the Mehlich-1 soil extract, which is also used for phosphorus extraction. Other laboratories use an anion exchange resin for P and also determine Ca, Mg and K in the same extract, while Al and Na cannot be determined. For this reason, it was considered a good opportunity to evaluate the simultaneous extraction of the five exchangeable cations: Al, Ca, Mg, K, and Na in a 1 mol L-1 NH4Cl solution, and compare the results with those obtained with potassium chloride and Mehlich-1 extractants. The soil

  7. Molten salt synthesis of potassium hexatitanate

    Science.gov (United States)

    Zaremba, T.

    2012-09-01

    Potassium hexatitanate fibrous crystals have been synthesized by a conventional solid-state reaction and via molten salt process. The molten salt process has been shown to be effective in preparing fine and non-agglomerated K2Ti6O13 whiskers. The type of molten salt (KCl, NaCl-KCl) has a significant effect on the chemical composition of the whiskers. By using a eutectic mixture of NaCl and KCl, the replacement of potassium ions in solid potassium hexatitanate by smaller sodium ions from the chloride flux can be achieved. The characterization of the samples was carried out by means of XRD, SEM, EDX and WDX.

  8. Nutritional potassium requirement for laying Japanese quails

    OpenAIRE

    Fernando Guilherme Perazzo Costa; Ladyanne Raia Rodrigues; Cláudia de Castro Goulart; Cleber Franklin Santos de Oliveira; Valéria Pereira Rodrigues; José Humberto Vilar da Silva

    2011-01-01

    The objective of this study was to evaluate the potassium requirement for laying Japanese quails. Two hundred and forty quails were distributed in a randomized block design, with five treatments and six replicates, with eight birds each. The treatments consisted of a basal diet deficient in potassium (K) (2.50 g/kg), supplemented with potassium carbonate, to replace the inert, to reach levels of 2.50, 3.50, 4.50, 5.50 and 6.50 (g/kg) of K in the diet. There was a quadratic effect of K levels ...

  9. Physiology of intracellular potassium channels: A unifying role as mediators of counterion fluxes?

    Science.gov (United States)

    Checchetto, Vanessa; Teardo, Enrico; Carraretto, Luca; Leanza, Luigi; Szabo, Ildiko

    2016-08-01

    Plasma membrane potassium channels importantly contribute to maintain ion homeostasis across the cell membrane. The view is emerging that also those residing in intracellular membranes play pivotal roles for the coordination of correct cell function. In this review we critically discuss our current understanding of the nature and physiological tasks of potassium channels in organelle membranes in both animal and plant cells, with a special emphasis on their function in the regulation of photosynthesis and mitochondrial respiration. In addition, the emerging role of potassium channels in the nuclear membranes in regulating transcription will be discussed. The possible functions of endoplasmic reticulum-, lysosome- and plant vacuolar membrane-located channels are also referred to. Altogether, experimental evidence obtained with distinct channels in different membrane systems points to a possible unifying function of most intracellular potassium channels in counterbalancing the movement of other ions including protons and calcium and modulating membrane potential, thereby fine-tuning crucial cellular processes. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-7, 2016', edited by Prof. Paolo Bernardi. PMID:26970213

  10. M-type potassium channels modulate Schaffer collateral-CA1 glutamatergic synaptic transmission.

    Science.gov (United States)

    Sun, Jianli; Kapur, Jaideep

    2012-08-15

    Previous studies have suggested that muscarinic receptor activation modulates glutamatergic transmission. M-type potassium channels mediate the effects of muscarinic activation in the hippocampus, and it has been proposed that they modulate glutamatergic synaptic transmission. We tested whether M1 muscarinic receptor activation enhances glutamatergic synaptic transmission via the inhibition of the M-type potassium channels that are present in Schaffer collateral axons and terminals. Miniature excitatory postsynaptic currents (mEPSCs) were recorded from CA1 pyramidal neurons. The M1 receptor agonist, NcN-A-343, increased the frequency of mEPSCs, but did not alter their amplitude. The M-channel blocker XE991 and its analogue linopirdine also increased the frequency of mEPSCs. Flupirtine, which opens M-channels, had the opposite effect. XE991 did not enhance mEPSCs frequency in a calcium-free external medium. Blocking P/Q- and N-type calcium channels abolished the effect of XE991 on mEPSCs. These data suggested that the inhibition of M-channels increases presynaptic calcium-dependent glutamate release in CA1 pyramidal neurons. The effects of these agents on the membrane potentials of presynaptic CA3 pyramidal neurons were studied using current clamp recordings; activation of M1 receptors and blocking M-channels depolarized neurons and increased burst firing. The input resistance of CA3 neurons was increased by the application of McN-A-343 and XE991; these effects were consistent with the closure of M-channels. Muscarinic activation inhibits M-channels in CA3 pyramidal neurons and its efferents – Schaffer collateral, which causes the depolarization, activates voltage-gated calcium channels, and ultimately elevates the intracellular calcium concentration to increase the release of glutamate on CA1 pyramidal neurons. PMID:22674722

  11. Histidine phosphorylation relieves copper inhibition in the mammalian potassium channel KCa3.1.

    Science.gov (United States)

    Srivastava, Shekhar; Panda, Saswati; Li, Zhai; Fuhs, Stephen R; Hunter, Tony; Thiele, Dennis J; Hubbard, Stevan R; Skolnik, Edward Y

    2016-01-01

    KCa2.1, KCa2.2, KCa2.3 and KCa3.1 constitute a family of mammalian small- to intermediate-conductance potassium channels that are activated by calcium-calmodulin. KCa3.1 is unique among these four channels in that activation requires, in addition to calcium, phosphorylation of a single histidine residue (His358) in the cytoplasmic region, by nucleoside diphosphate kinase-B (NDPK-B). The mechanism by which KCa3.1 is activated by histidine phosphorylation is unknown. Histidine phosphorylation is well characterized in prokaryotes but poorly understood in eukaryotes. Here, we demonstrate that phosphorylation of His358 activates KCa3.1 by antagonizing copper-mediated inhibition of the channel. Furthermore, we show that activated CD4(+) T cells deficient in intracellular copper exhibit increased KCa3.1 histidine phosphorylation and channel activity, leading to increased calcium flux and cytokine production. These findings reveal a novel regulatory mechanism for a mammalian potassium channel and for T-cell activation, and highlight a unique feature of histidine versus serine/threonine and tyrosine as a regulatory phosphorylation site. PMID:27542194

  12. A homology model of the pore domain of a voltage-gated calcium channel is consistent with available SCAM data

    OpenAIRE

    Bruhova, Iva; Zhorov, Boris S.

    2010-01-01

    In the absence of x-ray structures of calcium channels, their homology models are used to rationalize experimental data and design new experiments. The modeling relies on sequence alignments between calcium and potassium channels. Zhen et al. (2005. J. Gen. Physiol. doi:10.1085/jgp.200509292) used the substituted cysteine accessibility method (SCAM) to identify pore-lining residues in the Cav2.1 channel and concluded that their data are inconsistent with the symmetric architecture of the pore...

  13. Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate

    OpenAIRE

    Ivanov, Vadim; Ivanova, Svetlana; KALINOVSKY, TATIANA; NIEDZWIECKI, ALEKSANDRA; RATH, MATTHIAS

    2016-01-01

    Calcium, sodium and potassium channel blockers are widely prescribed medications for a variety of health problems, most frequently for cardiac arrhythmias, hypertension, angina pectoris and other disorders. However, chronic application of channel blockers is associated with numerous side effects, including worsening cardiac pathology. For example, nifedipine, a calcium-channel blocker was found to be associated with increased mortality and increased risk for myocardial infarction. In addition...

  14. Comparative efficacy of chlorine and chlorine dioxide regimes for condenser slime control in seawater cooled heat exchangers

    International Nuclear Information System (INIS)

    Chlorination has long been used as an effective and economic biocide for biofouling control in seawater cooling systems. However, the efficacy of chlorine is reduced in the presence of organic content of seawater and the inability of chlorine to effectively penetrate biofilms. Chlorine dioxide is being projected as a possible alternative to chlorine. Experiments were carried out with the help of a seawater circulating facility, in which direct comparison of the efficacy of the two biocides was possible using test condenser tube assemblies. The test condenser tubes made of titanium, SS 316L and Cu-Ni 90/10 were dosed with chlorine and chlorine dioxide. Each dose was evaluated for 30 days. Continuous and intermittent additions of chlorine (0.38 - 0.45 mg L-1 TRO) and chlorine dioxide (0.4 - 0.5 mg L-1) were used, along with control. The flow velocity in the tubes was maintained at 1.5 m/s. Results of the study showed that the efficacy of the biocide to control biofilms depended on the biocide and the material. Continuous chlorination resulted in 75% reduction of viable counts on titanium, followed by 24% reduction on CuNi and 6% reduction on SS 316L surfaces, as compared to the control. When compared to continuous chlorination, increase in bacterial density in the tubes was observed at different regimes of intermittent chlorination. On SS 316L and Cu-Ni surfaces, intermittent chlorination for 1h, once every 3 h, appeared to give adequate protection. Continuous addition of chlorine dioxide resulted in 99% reduction of viable counts on titanium surfaces, followed by 28% reduction on SS 316 L surfaces and 52% reduction on Cu-Ni surfaces, as compared to the controls. The data indicate that the efficacy of biocides to control biofilms depend on not only the biocide and its frequency of application but also the material of construction. (author)

  15. Comparative efficacy of chlorine and chlorine dioxide regimes for condenser slime control in seawater cooled heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, P.S.; Veeramani, P.; Ershath, M.; Rajamohan, R.; Harinath, Y.V.; Mohan, T.V.K.; Venugopalan, V.P. [BARC Facilities, Water and Steam Chemistry Div., Kalpakkam, Tamil nadu (India)

    2010-07-01

    Chlorination has long been used as an effective and economic biocide for biofouling control in seawater cooling systems. However, the efficacy of chlorine is reduced in the presence of organic content of seawater and the inability of chlorine to effectively penetrate biofilms. Chlorine dioxide is being projected as a possible alternative to chlorine. Experiments were carried out with the help of a seawater circulating facility, in which direct comparison of the efficacy of the two biocides was possible using test condenser tube assemblies. The test condenser tubes made of titanium, SS 316L and Cu-Ni 90/10 were dosed with chlorine and chlorine dioxide. Each dose was evaluated for 30 days. Continuous and intermittent additions of chlorine (0.38 - 0.45 mg L{sup -1} TRO) and chlorine dioxide (0.4 - 0.5 mg L{sup -1}) were used, along with control. The flow velocity in the tubes was maintained at 1.5 m/s. Results of the study showed that the efficacy of the biocide to control biofilms depended on the biocide and the material. Continuous chlorination resulted in 75% reduction of viable counts on titanium, followed by 24% reduction on CuNi and 6% reduction on SS 316L surfaces, as compared to the control. When compared to continuous chlorination, increase in bacterial density in the tubes was observed at different regimes of intermittent chlorination. On SS 316L and Cu-Ni surfaces, intermittent chlorination for 1h, once every 3 h, appeared to give adequate protection. Continuous addition of chlorine dioxide resulted in 99% reduction of viable counts on titanium surfaces, followed by 28% reduction on SS 316 L surfaces and 52% reduction on Cu-Ni surfaces, as compared to the controls. The data indicate that the efficacy of biocides to control biofilms depend on not only the biocide and its frequency of application but also the material of construction. (author)

  16. The development of a potassium-sulfide glass fiber cell and studies on impurities in alkali metal-sulfur cells

    Science.gov (United States)

    Tsang, F. Y.

    1977-01-01

    Potassium sulfur rechargeable cells, having as the electrolyte the thin walls of hollow glass fibers made from permeable glass, were developed. The cells had short lives, probably due to the construction materials and impurities in the potassium. The effect of the impurities in the analogous NA-S system was studied. Calcium, potassium, and NaOH/oxide impurities caused increased resistance or corrosion of the glass fibers. For long lived cell operation, the Na must contain less than 1 ppm Ca and less than a few ppm of hydroxide/oxide. Up to 150 ppm K can be tolerated. After purification of the Na anolyte, cell lifetimes in excess of 1000 deep charge-discharge cycles or over 8 months on continuous cycling at 10-30 percent depth of discharge were obtained.

  17. Recent Achievements in the Radiation-Catalysed Chlorination of Chlorinated Pentane Derivatives

    International Nuclear Information System (INIS)

    The radiation-catalysed chlorination of the so-called tetrachloro-cyclopentane, the product obtained from cyclopentadiene by addition of chlorine, has already been studied earlier by the authors with success. On maintaining an adequate dosage rate, no ring cleavage occurs, and, mainly for stereochemical reasons, octachloro-cyclopentene forms as an end product - similarly to conventional chlorination carried out at high temperature (400-500oC), but at substantially lower temperature (170oC) and without any resin formation. It is known that besides other end products, octachloro-cyclopentene forms also from perchlorinated pentane, under simultaneous cyclization. In their recent experiments presented here, the authors investigated how and to what extent the yield of octachloro-cyclopentene is affected by additional chlorination of pentane, previously chlorinated under cooling (at 10 to 30oC). The experiments were carried out with a Co60 radiation source of 330 c at a dosage rate of 8 x 103 to 8 x 104r/hr, in a heated reaction mixture, mixed with a chlorine stream for periods not exceeding 30 hr. It was found that also this type of chlorination and cyclization takes place at a temperature substantially lower than the conventional 500-600oC. According to the experiments, in this case it is advisable to raise the initial temperature of 170oC of the reaction gradually to 220oC with the progress of the reaction, in order to promote the cyclization reaction. It was found, namely, that first the paraffin chain was further chlorinated and later the perchlorinated pentane derivatives cyclize partly to octachloro-cyclopentene, under formation of other chlorinated alkane and alkene derivatives. This reaction mechanism was also supported by thermodynamical calculations. The end product contains three main components; its content of octachloro-cyclopentene ranges between 25 and 35%. The data required for the evaluation of the economy of the method will be available only on the

  18. Structural Role of Alkali Cations in Calcium Aluminosilicate Glasses as Examined Using Oxygen-17 Solid-State Nuclear Magnetic Resonance Spectroscopy

    Science.gov (United States)

    Sukenaga, Sohei; Kanehashi, Koji; Shibata, Hiroyuki; Saito, Noritaka; Nakashima, Kunihiko

    2016-08-01

    The structural roles of alkali and calcium cations are important for understanding the physical and chemical properties of aluminosilicate melts and glasses. Recently, oxygen-17 nuclear magnetic resonance (17O NMR) studies of calcium-sodium aluminosilicate glasses showed that these structural roles are not randomly given, but rather each cation has its own preferential role. However, the relationship between cation type and role preference in calcium aluminosilicate glass is not completely understood. In the present study, the structural roles of lithium, sodium, and potassium cations in selected calcium aluminosilicate glasses are investigated using 17O solid-state NMR experiments. Data from these experiments clearly show that potassium cations have a notably stronger tendency to act as charge compensators within the network structure, compared to sodium and lithium cations. The result of 17O NMR experiment also showed that sodium and lithium cations in part act as network modifier alongside with calcium cations.

  19. Structural Role of Alkali Cations in Calcium Aluminosilicate Glasses as Examined Using Oxygen-17 Solid-State Nuclear Magnetic Resonance Spectroscopy

    Science.gov (United States)

    Sukenaga, Sohei; Kanehashi, Koji; Shibata, Hiroyuki; Saito, Noritaka; Nakashima, Kunihiko

    2016-05-01

    The structural roles of alkali and calcium cations are important for understanding the physical and chemical properties of aluminosilicate melts and glasses. Recently, oxygen-17 nuclear magnetic resonance (17O NMR) studies of calcium-sodium aluminosilicate glasses showed that these structural roles are not randomly given, but rather each cation has its own preferential role. However, the relationship between cation type and role preference in calcium aluminosilicate glass is not completely understood. In the present study, the structural roles of lithium, sodium, and potassium cations in selected calcium aluminosilicate glasses are investigated using 17O solid-state NMR experiments. Data from these experiments clearly show that potassium cations have a notably stronger tendency to act as charge compensators within the network structure, compared to sodium and lithium cations. The result of 17O NMR experiment also showed that sodium and lithium cations in part act as network modifier alongside with calcium cations.

  20. Revisiting the thermochemistry of chlorine fluorides

    CERN Document Server

    Sánchez, H R

    2016-01-01

    In this work, accurate calculations of standard enthalpies of formation of chlorine fluorides (ClF$_n$, n=1--7; Cl$_2$F and Cl$_3$F$_2$) were performed through the isodesmic reactions scheme. It is argued that, for many chlorine fluorides, the gold standard method of quantum chemistry (CCSD(T)) is not capable to predict enthalpy values nearing chemical accuracy if atomization scheme is used. This is underpinned by a thorough analysis of total atomization energy results and the inspection of multireference features of these compounds. Other thermodynamic quantities were also calculated at different temperatures. In order to complement the energetic description, elimination curves were studied through density functional theory as a computationally affordable alternative to highly correlated wave function-based methods.

  1. Chlorine-Free Red-Burning Pyrotechnics.

    Science.gov (United States)

    Sabatini, Jesse J; Koch, Ernst-Christian; Poret, Jay C; Moretti, Jared D; Harbol, Seth M

    2015-09-01

    The development of a red, chlorine-free pyrotechnic illuminant of high luminosity and spectral purity was investigated. Red-light emission based solely on transient SrOH(g) has been achieved by using either 5-amino-1H-tetrazole or hexamine to deoxidize the combustion flame of a Mg/Sr(NO3 )2 /Epon-binder composition and reduce the amount of both condensed and gaseous SrO, which emits undesirable orange-red light. The new formulations were found to possess high thermal onset temperatures. Avoiding chlorine in these formulations eliminates the risk of the formation of PCBs, PCDDs, and PCDFs. This finding, hence, will have a great impact on both military pyrotechnics and commercial firework sectors. PMID:26333055

  2. Spectrographic determination of chlorine and fluorine

    International Nuclear Information System (INIS)

    Experimental conditions have been investigated in order to obtain the highest sensitivity in spectrographic determination of chlorine and fluorine using the Fassel method of excitation in an inert atmosphere. The influence of the nature of the atmosphere, of the discharge conditions and of the matrix material has been investigated. The following results have been established: 1. chlorine determination is definitely possible: a working curve has been drawn between 10 μg and 100 μg, the detection limit being around 5 μg; 2. fluorine determination is not satisfactory: the detection limit is still of the order of 80 μg. The best operating conditions have been defined for both elements. (author)

  3. Bacterial responses to reactive chlorine species.

    Science.gov (United States)

    Gray, Michael J; Wholey, Wei-Yun; Jakob, Ursula

    2013-01-01

    Hypochlorous acid (HOCl), the active ingredient of household bleach, is the most common disinfectant in medical, industrial, and domestic use and plays an important role in microbial killing in the innate immune system. Given the critical importance of the antimicrobial properties of chlorine to public health, it is surprising how little is known about the ways in which bacteria sense and respond to reactive chlorine species (RCS). Although the literature on bacterial responses to reactive oxygen species (ROS) is enormous, work addressing bacterial responses to RCS has begun only recently. Transcriptomic and proteomic studies now provide new insights into how bacteria mount defenses against this important class of antimicrobial compounds. In this review, we summarize the current knowledge, emphasizing the overlaps between RCS stress responses and other more well-characterized bacterial defense systems, and identify outstanding questions that represent productive avenues for future research. PMID:23768204

  4. Stability and effectiveness of chlorine disinfectants in water distribution systems.

    Science.gov (United States)

    Olivieri, V P; Snead, M C; Krusé, C W; Kawata, K

    1986-11-01

    A test system for water distribution was used to evaluate the stability and effectiveness of three residual disinfectants--free chlorine, combined chlorine, and chlorine dioxide--when challenged with a sewage contaminant. The test distribution system consisted of the street main and internal plumbing for two barracks at Fort George G. Meade, MD. To the existing pipe network, 152 m (500 ft) of 13-mm (0.5 in.) copper pipe were added for sampling, and 60 m (200 ft) of 2.54-cm (1.0 in.) plastic pipe were added for circulation. The levels of residual disinfectants tested were 0.2 mg/L and 1.0 mg/L as available chlorine. In the absence of a disinfectant residual, microorganisms in the sewage contaminant were consistently recovered at high levels. The presence of any disinfectant residual reduced the microorganism level and frequency of occurrence at the consumer's tap. Free chlorine was the most effective residual disinfectant and may serve as a marker or flag in the distribution network. Free chlorine and chlorine dioxide were the least stable in the pipe network. The loss of disinfectant in the pipe network followed first-order kinetics. The half-life determined in static tests for free chlorine, chlorine dioxide, and combined chlorine was 140, 93, and 1680 min. PMID:3028767

  5. Chlorine diffusion in CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Sadaiyandi, K.; Ramachandran, K. (School of Physics, Madurai Kamaraj Univ. (India))

    1991-06-01

    The experimental results of chlorine diffusion in CdTe reveal that the dominant mechanism for diffusion is through neutral defect pair such as (V{sub Cd}V{sub Te}){sup *}. Here, theoretical calculations are carried out for all the possible mechanisms such as single vacancy, single interstitial, neutral defect pair, and Frenkel defect pair. The results suggest that the most possible mechanism for Cl diffusion in CdTe is that through neutral defect pair, supporting the experiment. (orig.).

  6. Chlorine requirement for Japanese laying quails

    OpenAIRE

    Fernando Guilherme Perazzo Costa; Jalceyr Pessoa Figueiredo Júnior; Denise Fontana Figueiredo Lima; Cláudia de Castro Goulart; José Humberto Vilar da Silva; Matheus Ramalho de Lima; Sarah Gomes Pinheiro; Valéria Pereira Rodrigues

    2012-01-01

    The objective of this study was to determine the chlorine nutritional requirement of Japanese Quails during the laying phase, based on performance and egg quality parameters. A total of 240 Japanese quails were distributed according to a randomized block design, with five treatments and six replicates, with 8 birds each. The experiment lasted 84 days, divided in four cycles of 21 days each. Treatments consisted of a basal diet formulated to meet the nutritional requirements, except for chlori...

  7. Role of calcium in the constriction of isolated cerebral arteries

    International Nuclear Information System (INIS)

    Calcium entry blockers (CEB) have been used in the experimental treatment or prevention of many cerebrovascular disorders including stroke, post-ischemic hypoperfusion after cardiac arrest, cerebral vasospasm after subarachnoid hemorrhage, and migraine headache. However, the mechanism of action of these drugs on the cerebral circulation is poorly understood. This study examined the effects of calcium antagonists, Ca2+-deficient solutions, and vasocostrictors on cerebrovascular tone and 45Ca fluxes, to determine the role of calcium in cerebral arterial constriction. A Scatchard plot of 45Ca binding to BMCA showed that Ca2+ was bound at either low or high affinity binding sties. The four vasoconstrictors (potassium, serotonin, PGF/sub 2 α/, or SQ-26,655) each increased low affinity 45Ca uptake into BMCA. The results demonstrate that: (1) Potassium and serotonin constrict BMCA mainly by promoting Ca2+ influx through CEB-sensitive channels; (2) PGF/sub 2 α/ and SQ-26,655 constrict BMCA in part by promoting Ca2+ influx through CEB-sensitive channels, and in part by releasing Ca2+ from depletable internal stores; (3) The major action of CEB on BMCA is to block vasoconstrictor-induced Ca2+ uptake through both potential-operated (K+-stimulated) and receptor-operated channels

  8. Radiolytic degradation of chlorinated hydrocarbons in water

    International Nuclear Information System (INIS)

    Radiolytic degradation of chlorinated hydrocarbons (chloroform, trichloroethylene, and tetrachloroethylene) in water was carried out. Water solutions of the chlorinated hydrocarbons with different concentrations were irradiated with γ rays. Concentrations of methane, ethane, CO, CO2, H2, and O2 after the irradiation were determined by gas chromatography. Concentration of chloride ion in the irradiated sample was determined by ion chromatography. Experimental results show that radiolytic degradation of the chlorinated hydrocarbon increased with the radiation dose. Methane, ethane, CO2, H2, and Cl- concentrations increased with the radiation dose and the sample concentration. On the other hand, O2 concentration decreased with the radiation dose and the sample concentration. When sample concentration was high, dissolved oxygen might be not enough for converting most of the C atoms in the sample into CO2. This resulted in a low decomposition ratio. Addition of H2O2 as an oxygen resource could increase the decomposition ratio greatly. Furthermore, gas chromatography-mass spectroscopy was applied to identify some intermediates of the radiolytic dehalogenation. Radiolytic degradation mechanisms are also discussed. (author)

  9. Radioimmunoassay for chlorinated dibenzo-p-dioxins

    International Nuclear Information System (INIS)

    The invention provides a double-antibody radioimmunoassay method for the determination of chlorinated dibenzo-p-dioxins, particularly, 2,3,7,8-tetrachlorodibenzo-p-dioxin, in environmental samples including animal tissues such as monkey liver and adipose tissues. The limit of detection is approximately 25 picograms for 2,3,7,8-tetrachlorodibenzo-pdioxin. Assuming an appropriate cleanup procedure is used, chlorinated dibenzofurans are the only likely interferences, and these can be distinguished through the use of two antisers of different dibenzo-furan/dibenzodioxin selectivities. The invention includes the preparation of a reproducible antigen, an appropriate radiolabeled hapten, and effective sample extracts. A feature of the assay method is the use of a nonionic detergent (e.g., ''cutscum'' or ''triton x-305'') to solubilize the extremely hydrophobic dibenzo-p-dioxins in a manner permitting their binding by antibodies. The immunoassay is applicable to screening samples in order to minimize the demand for mass spectrometric screening, and to routine monitoring for exposure to known chlorinated dibenzo-p-dioxins in potentially contaminated environments

  10. Chlorination and Carbochlorination of Cerium Oxide

    International Nuclear Information System (INIS)

    The chlorination and carbochlorination of cerium oxide were studied by thermogravimetry under controlled atmosphere (TG) in the 7000C 9500C temperature range.Both reactants and products were analyzed by X-ray diffraction (RX), scanning electronic microscopy (SEM) and energy dispersive spectroscopy (EDS). Thermodynamic calculations were performed by computer assisted software.The chlorination starts at a temperature close to 8000C.This reaction involves the simultaneous formation and evaporation of CeCl3.Both processes control the reaction rate and their kinetic may not be easily separated.The apparent chlorination activation energy in the 8500C-9500C temperature range is 172 to 5 kJ/ mole.Carbon transforms the CeO2-Cl2 into a more reactive system: CeO2-C-Cl2, where the effects of the carbon content, total flow rate and temperature were analyzed.The carbochlorination starting temperature is 7000C.This reaction is completed in one step controlled by mass transfer with an apparent activation energy of 56 to 5 kJ/mole in the 8500C-9500C temperature range

  11. Suicidal Ingestion of Potassium Permanganate Crystals: A Rare Encounter

    OpenAIRE

    Karthik, Ravikanti; Veerendranath, Hari Prasad Kanakapura; Wali, Siddraj; Mohan, Murali N T; Kumar, Praveen A. C.; Trimurty, Gaganam

    2014-01-01

    Potassium permanganate poisoning is not common. Although Symptoms of potassium permanganate ingestion are gastrointestinal and Complications due to ingestion of potassium permanganate include cardiovascular depression, hepatic and renal damage, upper airway obstruction, bleeding tendency and methemoglobinemia. Gastric damage due to potassium permanganate has rarely been reported previously. We are reporting a 34-year old female patient who presented to our Emergency Department after suicidal ...

  12. Functional separation of deep cytoplasmic calcium from subplasmalemmal space calcium in cultured human uterine smooth muscle cells.

    Science.gov (United States)

    Young, Roger C; Zhang, PeiSheng

    2004-07-01

    For smooth muscle, two important functions of free intracellular calcium (Ca(2+)(i)) are modulation of plasma membrane excitability properties and modulation of the contractile apparatus. As proposed by van Breemen, Ca(2+)(i) can be divided into the subplasmalemmal space (Ca(2+)(sps)) and the deep cytosol (Ca(2+)(d)) by the superficial calcium buffer barrier. Using these distinctions, Ca(2+)(sps) activates the large conductance calcium-activated potassium channel (BK), and Ca(2+)(d) binds calcium-dependent fluorescent probes in the cytoplasm. We present here combined fluorescence-patch clamp experiments designed to simultaneously assess Ca(2+)(d) and Ca(2+)(sps) in cultured human uterine smooth muscle cells. Open probabilities (P(o)) of the BK channel were measured using the cell-attached patch clamp technique. P(o) was used to approximate changes of [Ca(2+)(sps)]. Relative concentrations of Ca(2+)(d) were approximated by observing fluorescence of Calcium green-1 (F). Under control conditions, we found similar time courses for rises of P(o) and F following 10nM oxytocin (OT) addition. In parallel experiments, but with lanthanum (La(3+)) added to the bath to block transmembrane calcium flux, P(o) was only slightly affected, but F increases were delayed and blunted. These data paradoxically indicate that following OT stimulation, the primary source of calcium for Ca(2+)(sps) is internal stores, and calcium entry from the extracellular space is required to raise Ca(2+)(d). When cells were exposed to cyclopiazonic acid (CPA) to release SR calcium stores, P(o) increased slowly, then persisted at large values. The persistence of P(o) rises suggests that removal of calcium from the subplasmalemmal space is primarily via reuptake into the SR. In the presence of La(3+), OT-induced rises of F were slightly prolonged, suggesting that transmembrane calcium flux contributes to decreasing Ca(2+)(d), but is not the primary mechanism. In summary, these data demonstrate that Ca(2

  13. Genetics Home Reference: potassium-aggravated myotonia

    Science.gov (United States)

    ... myotonia Patient Support and Advocacy Resources (2 links) Muscular Dystrophy Association Resource list from the University of Kansas Medical Center Genetic Testing Registry (1 link) Potassium aggravated myotonia ClinicalTrials. ...

  14. Low Potassium Diet (Beyond the Basics)

    Science.gov (United States)

    ... to 120 mL/min) . A registered dietitian or nutritionist can help to create a low-potassium meal ... volumes. You agree to comply with all applicable laws, including all US export laws and regulations, in ...

  15. Transition properties of potassium atom

    CERN Document Server

    Nandy, D K; Shah, B P; Sahoo, B K

    2012-01-01

    We report here oscillator strengths, transition rates, branching ratios and lifetimes due to allowed transitions in potassium (K) atom. We evaluate electric dipole (E1) amplitudes using an all order relativistic many-body perturbation method. The obtained results are compared with previously available experimental and theoretical studies. Using the E1 matrix elements mentioned above and estimated from the lifetimes of the 4P states, we determine precise values of static and dynamic polarizabilities for the first five low-lying states in the considered atom. The static polarizabilities of the ground and 4P states in the present work are more precise than the available measurements in these states. Only the present work employs relativistic theory to evaluate polarizabilities in the 3D states for which no experimental results are known to compare with. We also reexamine "magic wavelengths" for the $4P_{1/2} \\rightarrow 4S$ and $4P_{3/2} \\rightarrow 4S$ transitions due to the linearly polarized light which are u...

  16. Independent effects of aldosterone and potassium on induction of potassium adaptation in rat kidney.

    OpenAIRE

    Stanton, B.; Pan, L.; Deetjen, H; Guckian, V; Giebisch, G

    1987-01-01

    We examined the independent effects of a high potassium diet and increased aldosterone levels on the development of renal potassium adaptation. This condition is defined by the increased ability of the kidneys to excrete an acute infusion of potassium. Rats were adrenalectomized (ADX) and received aldosterone at basal levels (0.5 microgram/100 g X d) or at high levels (2.0 micrograms/100 g X d) for 10 d. In each experimental group, animals received either a control diet or a high potassium di...

  17. Neuronal calcium sparks and intracellular calcium “noise”

    OpenAIRE

    Melamed-Book, Naomi; Kachalsky, Sylvia G.; Kaiserman, Igor; Rahamimoff, Rami

    1999-01-01

    Intracellular calcium ions are involved in many forms of cellular function. To accommodate so many control functions, a complex spatiotemporal organization of calcium signaling has developed. In both excitable and nonexcitable cells, calcium signaling was found to fluctuate. Sudden localized increases in the intracellular calcium concentration—or calcium sparks—were found in heart, striated and smooth muscle, Xenopus Laevis oocytes, and HeLa and P12 cells. In the nervous system, intracellular...

  18. POTASSIUM MEASUREMENT: CAUSES OF ERRORS IN MEASUREMENT

    OpenAIRE

    Kavitha; Omprakash

    2014-01-01

    It is not a easy task to recognize the errors in potassium measurement in the lab. Falsely elevated potassium levels if goes unrecognized by the lab and clinician, it is difficult to treat masked hypokalemic state, which is again a medical emergency. Such cases require proper monitoring by the clinician, so that cases with such history of pseudohyperkalemia which cannot be easily identified in the laboratory should not go unrecognized by clinician. The aim of this article is t...

  19. Potassium permanganate ingestion as a suicide attempt

    OpenAIRE

    Tuba Cimilli Ozturk; Ozlem Guneysel; Onur Yesil; Sebnem Eren Cevik

    2012-01-01

    Potassium permanganate is a highly corrosive, water-soluble oxidizing antiseptic. A 68- year-old female patient was admitted to our Emergency Department after ingestion of 3 tablets of 250 mg potassium permanganate as a suicide attempt. The physical exam revealed brown stained lesions in the oropharynx. Emergency endoscopy was performed by the gastroenterologist after the third hour of ingestion. Emergency endoscopy revealed multiple superficial (Grade I-II) lesions on the esophagus and cardi...

  20. Potassium Permanganate Poisoning: A Nonfatal Outcome

    OpenAIRE

    Eteiwi, Suzan M.; Al-Eyadah, Abdallah A.; Al-Sarihin, Khaldon K.; Ahmad A. Al-Omari; Rania A. Al-Asaad; Haddad, Fares H.

    2015-01-01

    Acute poisoning by potassium permanganate is a rare condition with high morbidity and mortality. Diagnosis of the condition relies on a history of exposure or ingestion and a high degree of clinical suspicion. Oxygen desaturation and the presence of methemoglobin are also helpful indicators. Since no specific antidote is available, treatment is mainly supportive. Few cases have been reported in the literature following potassium permanganate ingestion, whether intentional or accidental, and m...

  1. Radioactivity measurements in potassium enriched vegetation

    International Nuclear Information System (INIS)

    Measurements of radioactivity in food stuffs/vegetation is important because radiation dose to human population due to inhalation and ingestion (external and internal exposure) poses health hazard and contribute significantly to the total dose from natural sources. The radium and thorium isotopes always present in the body are measured in units of a millionth or a billionth of a gram, but when it comes to potassium we are talking about grams of material. The 2.5 g of potassium ingested each day contains 80 Becquerel (Bq) (or 2100 pCi) of 40K that quantity which produces 80 radioactive decays each second. The 140 g of potassium in a normal male contains about 4400 Bq (or 120,000 pCi) of 40K; that quantity produces a decay rate of about 4400 disintegrations per second. That means that 4400 radioactive 40K atoms decay and emit radiation in our bodies each second for as long as we live. Since potassium is found in the intracellular fluids, about 98 % of the potassium in the body is within cells. Thus at least 98 % of these disintegrations take place within body cells, and are potentially capable of altering the cell's DNA. Therefore, it is very essential to measure the activity concentration in the potassium enriched food stuffs. Knowledge of radioactivity present in potassium enriched food stuffs enables one to assess any possible radiological hazard to mankind by the use of such materials. In the light of the above mentioned facts, it is, therefore, fundamental to assess the radioactivity in commonly available potassium enriched foods. (author)

  2. On specific radioactivity of potassium in seawater

    International Nuclear Information System (INIS)

    To check up the validity of an assumption on the constancy of potassium specific radioactivity Asub(k) in seawater, 14 samples selected from the Pacific Ocean in 1982 at different depths and geographic coordinates have been investigated. The Asub(k) mean value in these samples is shown to coincide with the potassium aspecific activity in terrestrial rocks. However some deviations related to sampling latitude and deoth have been observed. The deviations are associated with the entries of cosmic and volcanic substances

  3. Estimated potassium content in Hanford workers

    International Nuclear Information System (INIS)

    Potassium content in male and female workers at the US Dept. of Energy Hanford Site was estimated based on measurements made in 2002 of 40K activity in the body. The 40K activity in females ranged from 2.1 to 4.1 kBq with an average of 3.1 ± 0.02 kBq. The total body potassium (TBK) content in females averaged 98 ± 0.6 g. The 40K activity in males ranged from 2.8 to 6.6 kBq with an average of 4.2 ± 0.01 kBq and the average TBK was 136 ± 0.3 g. The average TBK value for males aged 20-49 y was 140 g. The average TBK values for both genders decreased with age. The average potassium concentrations calculated for the different age ranges for males were 15-25% less than the value (1.9 gK per kg) obtained using the reported ICRP reference potassium and reference weight values. Potassium concentrations were inversely correlated with body-build index, body-mass index and body weight. These correlations could possibly be utilised to help assess the risk for disease. Future work is planned to evaluate whether monitoring of potassium concentrations could be used as a tool for the detection of diabetes and hypertension. (authors)

  4. Estimated Potassium Content in Hanford Workers

    International Nuclear Information System (INIS)

    Potassium content in male and female workers at the Department of Energy Hanford Site was estimated based on measurements made in 2002 of 40K activity in the body. A coaxial germanium detection system was used for the measurements. The activity in female workers ranged from 2.1 to 4.1 kBq with an average of 3.1 ± 0.02 kBq. Total body potassium (TBK) content in female workers averaged 96 ± 0.3 g. The activity in male workers ranged from 2.8 to 6.6 kBq with an average of 4.3 ± 0.01 kBq and the average TBK was 136 ± 0.3 g. The average potassium concentration decreased with age in both males and females. The average potassium content and potassium concentrations for both males and females were less than the corresponding reference values. Potassium concentrations were inversely correlated with body-build index, body-mass index, and body weight for both males and females

  5. Attacks of Asthma due to Chlorinized Water: Case Report

    Directory of Open Access Journals (Sweden)

    Murat Eyup Berdan

    2008-02-01

    Full Text Available The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure to strong respiratory irritant with chlorinized water in two subjects with no past history of asthma or atopy. We conclude that airway hyperresponsiveness can develop or increase after chronic inhalation of high concentrations of irritants such as chlorinized water an indoor irritant factor and that these changes may be prolonged. [TAF Prev Med Bull. 2008; 7(1: 87-90

  6. Attacks of Asthma due to Chlorinized Water: Case Report

    Directory of Open Access Journals (Sweden)

    Murat Eyup Berdan

    2008-02-01

    Full Text Available The presence of a high prevalence of bronchial hyperresponsiveness and asthma-like symptoms in swimmers has been reported. But, attacks of asthma which is related to chlorinized water is rare. Chlorine, a strong oxidizing agent, is an important toxic gas that the swimmer can breath during swimming and a worker can exposed to chlorine while he or she was using water with chlorine at home. We describe a persistent increase in nonspecific bronchial hyperresponsiveness following chronic exposure to strong respiratory irritant with chlorinized water in two subjects with no past history of asthma or atopy. We conclude that airway hyperresponsiveness can develop or increase after chronic inhalation of high concentrations of irritants such as chlorinized water an indoor irritant factor and that these changes may be prolonged. [TAF Prev Med Bull 2008; 7(1.000: 87-90

  7. Electric plasma discharge combustion synthesis of chlorine dioxide

    International Nuclear Information System (INIS)

    A process for the production of chlorine dioxide comprises feeding an inert gas to a reaction zone and applying an electrical discharge to the inert gas to produce a high temperature plasma. Chlorine gas and oxygen gas are supplied simultaneously to the reaction zone and reacted in the plasma to produce a gaseous mixture comprised of chlorine dioxide, chlorine, oxygen and inert gas, the molar ratio of oxygen to chlorine in the reaction zone being at least about 2.5;1. The gaseous mixture is recovered from the reaction zone. Chlorine dioxide, which may be recovered as a gas or reacted to produce an alkali metal chlorite, is employed as a bleaching agent and a water treatment agent

  8. Calcium binding by dietary fibre

    International Nuclear Information System (INIS)

    Dietary fibre from plants low in phytate bound calcium in proportion to its uronic-acid content. This binding by the non-cellulosic fraction of fibre reduces the availability of calcium for small-intestinal absorption, but the colonic microbial digestion of uronic acids liberates the calcium. Thus the ability to maintain calcium balance on high-fibre diets may depend on the adaptive capacity on the colon for calcium. (author)

  9. Some kinetics aspects of chlorine-solids reactions

    OpenAIRE

    Kanari, N.; Mishra, D.; Mochón, J.; Verdeja, L. F.; Diot, F.; Allain, E.

    2011-01-01

    The present paper describes detailed kinetics investigations on some selected chlorine-solid reactions through thermogravimetric measurements. The solids studied in this article include chemical pure oxides and sulfides as well as their natural bearing materials. The chlorinating agents employed are gaseous mixtures of Cl2+N2 (chlorination), Cl2+O2 (oxychlorination), and Cl2+CO (...

  10. The removal of phenols from oily wastewater by chlorine dioxide

    OpenAIRE

    Hsu, Chung-Jung

    1988-01-01

    Treatability studies were performed on oily wastewaters produced by petroleum and canning industries. Chlorine dioxide was used for the removal of phenolic compounds from these oily wastewaters. Most of phenolic compounds can be destroyed by chlorine dioxide within 15 minutes if CI02-to-phenol ratios of higher than 5.0 are provided. Factors such as pH, temperature, and COD have little effect on phenol removal. The effectiveness of chlorine dioxide treatment depends critic...

  11. Palau’chlor: A Practical and Reactive Chlorinating Reagent

    OpenAIRE

    Rodriguez, Rodrigo A.; Pan, Chung-Mao; Yabe, Yuki; Kawamata, Yu; Eastgate, Martin D.; Baran, Phil S.

    2014-01-01

    Unlike its other halogen atom siblings, the utility of chlorinated arenes and (hetero)arenes are twofold: they are useful in tuning electronic structure as well as acting as points for diversification via cross-coupling. Herein we report the invention of a new guanidine-based chlorinating reagent, CBMG or “Palau’chlor”, inspired by a key chlorospirocyclization en route to pyrrole imidazole alkaloids. This direct, mild, operationally simple, and safe chlorinating method is compatible with a ra...

  12. Blends of caprolactam/caprolactone copolymers and chlorinated polymers

    OpenAIRE

    Alberda van Ekenstein, G.O.R.; Deuring, H.; ten Brinke, G.; Ellis, T. S.

    1997-01-01

    The phase behaviour of blends of chlorinated polyethylene, polyvinyl chloride (PVC) and chlorinated PVC with random copolymers of caprolactone and caprolactam has been investigated and the results correlated with a binary interaction model. The known miscibility of polycaprolactone in the chlorinated polymers is not compromised until a relatively high lactam content in the copolymer is attained. The incorporation of segmental interaction parameters, derived from separate studies involving pol...

  13. Cytohistochemical techniques for calcium localization and their application to diseased plants.

    Science.gov (United States)

    Stockwell, V; Hanchey, P

    1982-07-01

    Lesion delimitation and resistance of old bean (Phaselous vulgaris L., cv. Red Kidney) plants to Rhizoctonia solani Kühn have been suggested to result from increased calcium pectate formation in walls. Ultrastructural histochemistry was used to determine the site of calcium in tissues adjacent to lesions and in older bean hypocotyls. Hypocotyl lesion tissue and uninoculated control tissue were treated with ammonium oxalate or potassium pyroantimonate during fixation. Treatment with potassium pyroantimonate, but not with oxalate, resulted in granular deposits in cell walls of healthy and lesion tissue. Granules also occurred on the plasma membrane of cells adjacent to lesions and in organelles of damaged cells, but wall granule density was not increased. Cell walls from healthy 24-day-old plants had a greater granule density than those for 8-day-old plants. Wall granules were removed from thin sections with ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. Energy dispersive analysis of x-rays also suggested that potassium pyroantimonate localized calcium. Chemical analyses showed that some calcium was retained in tissues after fixation. The results suggest that there are different mechanisms for lesion delimitation and age-induced resistance. PMID:16662455

  14. [Calcium suppletion for patients who use gastric acid inhibitors: calcium citrate or calcium carbonate?].

    NARCIS (Netherlands)

    Jonge, H.J. de; Gans, R.O.; Huls, G.A.

    2012-01-01

    Various calcium supplements are available for patients who have an indication for calcium suppletion. American guidelines and UpToDate recommend prescribing calcium citrate to patients who use antacids The rationale for this advice is that water-insoluble calcium carbonate needs acid for adequate ab

  15. Transverse thermal magnetoresistance of potassium

    International Nuclear Information System (INIS)

    Results are presented of extensive thermal magnetoresistance measurements on single-crystal and polycrystalline specimens of potassium having residual resistance ratios (RRR) ranging from 1100 to 5300. Measurements were made between 2 and 90K for magnetic fields up to 1.8 T. The observed thermal magnetoresistance cannot be understood on the basis of either semiclassical theories or from the electrical magnetoresistance and the Wiedemann-Franz law. A number of relationships are observed between the thermal and electrical magnetoresistances, many of which are not immediately obvious when comparing direct experimental observations. The thermal magnetoresistance W(T,H) is given reasonably well by W(T,H)T = W(T,0)T + AH + BH2, where both A and B are temperature-dependent coefficients. Results show that A = A0 + A1T3, while B(T) cannot be expressed as any simple power law. A0 is dependent on the RRR, while A1 is independent of the RRR. Two relationships are found between corresponding coefficients in the electrical and thermal magnetoresistance: (i) the Wiedmann--Franz law relates A0 to the Kohler slope of the electrical magnetoresistance and (ii) the temperature-dependent portions of the electrical and thermal Kohler slopes are both proportional to the electron--phonon scattering contribution to the corresponding zero-field resistance. The latter provides evidence that inelastic scattering is very important in determining the temperature-dependent linear magnetoresistances. Part, but by no means all, of the quadratic thermal resistance is accounted for by lattice thermal conduction. It is concluded that at least a portion of the anomalous electrical and thermal magnetoresistances is due to intrinsic causes and not inhomogeneities or other macroscopic defects

  16. Mechanism of electromechanical coupling in voltage-gated potassium channels

    Directory of Open Access Journals (Sweden)

    RikardBlunck

    2012-09-01

    Full Text Available Voltage-gated ion channels play a central role in the generation of action potentials in the nervous system. They are selective for one type of ion – sodium, calcium or potassium. Voltage-gated ion channels are composed of a central pore that allows ions to pass through the membrane and four peripheral voltage sensing domains that respond to changes in the membrane potential. Upon depolarization, voltage sensors in voltage-gated potassium channels (Kv undergo conformational changes driven by positive charges in the S4 segment and aided by pairwise electrostatic interactions with the surrounding voltage sensor. Structure-function relations of Kv channels have been investigated in detail, and the resulting models on the movement of the voltage sensors now converge to a consensus; the S4 segment undergoes a combined movement of rotation, tilt and vertical displacement in order to bring 3-4 e+ each through the electric field focused in this region. Nevertheless, the mechanism by which the voltage sensor movement leads to pore opening, the electromechanical coupling, is still not fully understood. Thus, recently, electromechanical coupling in different Kv channels has been investigated with a multitude of techniques including electrophysiology, 3D crystal structures, fluorescence spectroscopy and molecular dynamics simulations. Evidently, the S4-S5 linker, the covalent link between the voltage sensor and pore, plays a crucial role. The linker transfers the energy from the voltage sensor movement to the pore domain via an interaction with the S6 C-termini, which are pulled open during gating. In addition, other contact regions have been proposed. This review aims to provide (i an in-depth comparison of the molecular mechanisms of electromechanical coupling in different Kv channels; (ii insight as to how the voltage sensor and pore domain influence one another; and (iii theoretical predictions on the movement of the cytosolic face of the KV channels

  17. Mechanisms of inactivation of poliovirus by chlorine dioxide and iodine.

    OpenAIRE

    Alvarez, M E; O'Brien, R T

    1982-01-01

    Chlorine dioxide and iodine inactivated poliovirus more efficiently at pH 10.0 than at pH 6.0. Sedimentation analyses of viruses inactivated by chlorine dioxide and iodine at pH 10.9 showed that viral RNA separated from the capsids, resulting in the conversion of virions from 156S structures to 80S particles. The RNAs release from both chlorine dioxide- and iodine-inactivated viruses cosedimented with intact 35S viral RNA. Both chlorine dioxide and iodine reacted with the capsid proteins of p...

  18. Water splitting processes of the iron-chlorine family

    International Nuclear Information System (INIS)

    Multi-step processes for thermal water splitting comprise individual chemical reactions which, as far as the iron-chlorine family is concerned, may be generalized: hydrolysis, chlorination, dechlorination, reduction, regeneration of chlorinating agent. These categories comprise series of chemical equations which can be combined to water splitting cycles in different configurations. A systematic estimation of the chemical equations of the five categories is given instead of treating several hundred water-splitting processes of the iron-chlorine family. The individual chemical equations are estimated from published data, by laboratory experiments, and by operating conditions of technical processes. (author)

  19. Stimulatory effects of maitotoxin on insulin release in insulinoma HIT cells: Role of calcium uptake and phosphoinositide breakdown

    International Nuclear Information System (INIS)

    In hamster insulinoma (HIT) cells, maitotoxin (MTX) induces a time-dependent and concentration-dependent release of insulin that requires the presence of extracellular calcium. The response is nearly completely blocked by cinnarizine and cadmium, but is not inhibited by the L-type calcium channel blocker nifedipine or by manganese. MTX induces 45Ca+ uptake in these cells in a dose-dependent mode, and the uptake is blocked with cinnarizine, nifedipine and cadmium, and is partially inhibited by manganese. MTX induces phosphoinositide breakdown in HIT cells, and the response is partially blocked by cadmium, but is not affected by nifedipine, cinnarizine or manganese. High concentrations of potassium ions also induce insulin release and calcium uptake in HIT cells. Both effects of potassium are blocked partially by nifedipine, cadmium and cinnarizine. High concentrations of potassium do not induce phosphoinositide breakdown in HIT cells. The results suggest that MTX-elicited release of insulin is attained by two mechanisms: (1) a nifedipine-sensitive action, which results from MTX-induced activation of L-type calcium channels, which can be mimicked with high potassium concentrations; and (2) a nifedipine-insensitive action, which may be initiated by the activation of phosphoinositide breakdown by MTX. Such an activation of phospholipase C would result in the formation of 1,4,5-inositol trisphosphate, a release of intracellular calcium and then release of insulin to the extracellular space. Cinnarizine is proposed to block both MTX-elicited mechanisms, the first by blockade of calcium channels and the second by blocking 1,4,5-inositol trisphosphate-induced release of internal calcium. Either mechanism alone appears capable of eliciting release of insulin

  20. Calcium in plant cells

    Directory of Open Access Journals (Sweden)

    V. V. Schwartau

    2014-04-01

    Full Text Available The paper gives the review on the role of calcium in many physiological processes of plant organisms, including growth and development, protection from pathogenic influences, response to changing environmental factors, and many other aspects of plant physiology. Initial intake of calcium ions is carried out by Ca2+-channels of plasma membrane and they are further transported by the xylem owing to auxins’ attractive ability. The level of intake and selectivity of calcium transport to ove-ground parts of the plant is controlled by a symplast. Ca2+enters to the cytoplasm of endoderm cells through calcium channels on the cortical side of Kaspary bands, and is redistributed inside the stele by the symplast, with the use of Ca2+-АТPases and Ca2+/Н+-antiports. Owing to regulated expression and activity of these calcium transporters, calclum can be selectively delivered to the xylem. Important role in supporting calcium homeostasis is given to the vacuole which is the largest depo of calcium. Regulated quantity of calcium movement through the tonoplast is provided by a number of potential-, ligand-gated active transporters and channels, like Ca2+-ATPase and Ca2+/H+ exchanger. They are actively involved in the inactivation of the calcium signal by pumping Ca2+ to the depo of cells. Calcium ATPases are high affinity pumps that efficiently transfer calcium ions against the concentration gradient in their presence in the solution in nanomolar concentrations. Calcium exchangers are low affinity, high capacity Ca2+ transporters that are effectively transporting calcium after raising its concentration in the cell cytosol through the use of protons gradients. Maintaining constant concentration and participation in the response to stimuli of different types also involves EPR, plastids, mitochondria, and cell wall. Calcium binding proteins contain several conserved sequences that provide sensitivity to changes in the concentration of Ca2+ and when you

  1. A histochemical and X-ray microanalysis study of calcium changes in insect flight muscle degeneration in Solenopsis, the queen fire ant

    Energy Technology Data Exchange (ETDEWEB)

    Jones, R.G.; Davis, W.L.; Vinson, S.B.

    1982-04-01

    Potassium pyroantimonate histochemistry, coupled with ethyleneglycoltetraacetic acid (EGTA)-chelation and X-ray microprobe analysis, was employed to localize intracellular calcium binding sites in the normal and degenerating flight musculature in queens of Solenopsis, the fire ant. In normal animals, calcium distribution was light to moderate within myofibrils and mitochondria. In the early contracture stages of the insemination-induced degeneration, both myofilament and mitochondrial calcium loading was markedly increased. In the terminal stages of myofibril breakdown, only Z-lines (isolated or in clusters) with an associated filamentous residue persisted. These complexes were also intensely calcium positive. This study further documents the presence of increased sarcoplasmic calcium during muscle necrosis. Surface membrane defects, mitochondrial calcium overload, and calcium-activated proteases may all be involved in this ''normal'' breakdown process.

  2. A histochemical and X-ray microanalysis study of calcium changes in insect flight muscle degeneration in Solenopsis, the queen fire ant

    International Nuclear Information System (INIS)

    Potassium pyroantimonate histochemistry, coupled with ethyleneglycoltetraacetic acid (EGTA)-chelation and X-ray microprobe analysis, was employed to localize intracellular calcium binding sites in the normal and degenerating flight musculature in queens of Solenopsis, the fire ant. In normal animals, calcium distribution was light to moderate within myofibrils and mitochondria. In the early contracture stages of the insemination-induced degeneration, both myofilament and mitochondrial calcium loading was markedly increased. In the terminal stages of myofibril breakdown, only Z-lines (isolated or in clusters) with an associated filamentous residue persisted. These complexes were also intensely calcium positive. This study further documents the presence of increased sarcoplasmic calcium during muscle necrosis. Surface membrane defects, mitochondrial calcium overload, and calcium-activated proteases may all be involved in this ''normal'' breakdown process

  3. Effect of potassium oxalate on liver function and kidney tissue of dogs (beagles

    Directory of Open Access Journals (Sweden)

    Mohamaden Walaa

    2013-01-01

    Full Text Available Calcium oxalate crystalluria is a problem of growing concern in dogs. A few reports have discussed acute kidney injury by oxalates in dogs, describing ultrastructural findings in particular. We evaluated the possibility of deposition of calcium oxalate crystals in renal tissue and its probable consequences. Six dogs were intravenously injected with 0.5 M potassium oxalate (KOx for seven consecutive days. By the end of the experiment, ultrasonography revealed a significant increase in the renal mass and renal parenchymal echogenicity. Serum creatinine and blood urea nitrogen levels were gradually increased. The histopathological features of the kidneys were assessed by both light and electron microscopy, which showed CaOx crystal deposition accompanied by morphological changes in the renal tissue of KOx injected dogs. Canine renal oxalosis provides a good model to study the biological and pathological changes induced upon damage of renal tissue by KOx injection.

  4. Potassium acetate and potassium lactate enhance the microbiological and physical properties of marinated catfish fillets

    Science.gov (United States)

    Sodium or potassium salts such as lactate and acetate can be used to inhibit the growth of spoilage bacteria and food-borne pathogens, and thereby prolong the shelf-life of refrigerated seafood. However, minimal information is available regarding the combined effects of potassium salts (acetate and ...

  5. Mutagenic activity associated with by-products of drinking water disinfection by chlorine, chlorine dioxide, ozone and UV-irradiation.

    OpenAIRE

    Zoeteman, B C; Hrubec, J.; De Greef, E; Kool, H J

    1982-01-01

    A retrospective epidemiological study in The Netherlands showed a statistical association between chlorination by-products in drinking water and cancer of the esophagus and stomach for males. A pilot-plant study with alternative disinfectants was carried out with stored water of the Rivers Rhine and Meuse. It was demonstrated that the increase of direct acting mutagens after treatment with chlorine dioxide is similar to the effect of chlorination. Ozonation of Rhine water reduced the mutageni...

  6. Synthesis of carbon-11 labelled calcium channel antagonists

    International Nuclear Information System (INIS)

    A useful synthetic approach to carbon-11 labelled 1,4-dihydropyridines is described. Carbon-11 labelled calcium channel antagonists 11C-Nifedipine, 11C-Nisoldipine, 11C-nitrendipine and 11C-CF3-Nifedipine were synthesized by a modified Hantzsch method using protected carboxy functions. Deprotection of the carboxylic acids by alkaline hydrolysis followed by conversion into the corresponding potassium salts and subsequent methylation with 11CH3I produced the labelled compounds in very good chemical and radiochemical yields (94%). (author)

  7. Development of potassium ion conducting hollow glass fibers. [potassium sulfur battery

    Science.gov (United States)

    Tsang, F. Y.

    1974-01-01

    Potassium ion conducting glasses, chemically resistant to potassium, potassium sulfide and sulfur, were made and their possible utility as the membrane material for a potassium/sulfur battery was evaluated. At least one satisfactory candidate was found. It possesses an electrical resistance which makes it usable as a membrane in the form of a fine hollow fiber. It's chemical and electrochemical resistances are excellent. The other aspects of the possible potassium sulfur battery utilizing such fine hollow fibers, including the header (or tube sheet) and a cathode current collector were studied. Several cathode materials were found to be satisfactory. None of the tube sheet materials studied possessed all the desired properties. Multi-fiber cells had very limited life-time due to physical failure of fibers at the fiber/tube sheet junctions.

  8. Scenarios Evaluation Tool for Chlorinated Solvent MNA

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, Karen; Michael J. Truex; Charles J. Newell; Brian Looney

    2007-02-28

    Over the past three decades, much progress has been made in the remediation of chlorinated solvents from the subsurface. Yet these pervasive contaminants continue to present a significant challenge to the U.S. Department of Energy (DOE), other federal agencies, and other public and private organizations. The physical and chemical properties of chlorinated solvents make it difficult to rapidly reach the low concentrations typically set as regulatory limits. These technical challenges often result in high costs and long remediation time frames. In 2003, the DOE through the Office of Environmental Management funded a science-based technical project that uses the U.S. Environmental Protection Agency's technical protocol (EPA, 1998) and directives (EPA, 1999) on Monitored Natural Attenuation (MNA) as the foundation on which to introduce supporting concepts and new scientific developments that will support remediation of chlorinated solvents based on natural attenuation processes. This project supports the direction in which many site owners want to move to complete the remediation of their site(s), that being to complete the active treatment portion of the remedial effort and transition into MNA. The overarching objective of the effort was to examine environmental remedies that are based on natural processes--remedies such as Monitored Natural Attenuation (MNA) or Enhanced Attenuation (EA). The research program did identify several specific opportunities for advances based on: (1) mass balance as the central framework for attenuation based remedies, (2) scientific advancements and achievements during the past ten years, (3) regulatory and policy development and real-world experience using MNA, and (4) exploration of various ideas for integrating attenuation remedies into a systematic set of ''combined remedies'' for contaminated sites. These opportunities are summarized herein and are addressed in more detail in referenced project documents and

  9. Role of potassium-40 in evolutionary mutagenesis

    International Nuclear Information System (INIS)

    The radioactive isotope 40k is the largest source of natural radioactivity within living cells. Although 40K occurs naturally in low abundance (0.01% of all potassium), it represents approximately 40% of the internal radiation dose in man. It has been suggested that decay of 40K by electron capture has played a significant role in gene mutation and evolution. The authors examined cell growth and mutagenicity in several strains of E. coli grown in Tris medium containing natural potassium or potassium greatly depleted in 40K. Doubling times were the same in both media. In glucose limited chemostat cultures containing natural potassium or depleted potassium, there was no significant difference in mutation rate to bacteriophage T5 resistance, within standard errors of about 15%. In all cases, the mutation rate to T5 resistance was approximately 3 x 10-8 mutants cell-1 generation-1. The authors conclude that for mutation to T5 resistance, there was no measurable contribution of naturally occurring 40K to the spontaneous mutation rate

  10. Electrical properties of the potassium polytitanate compacts

    International Nuclear Information System (INIS)

    Highlights: • Quasi-static permittivity of potassium polytitanates compacts achieves 104–105. • Observed Maxwell–Wagner polarization attributes to layered structure of polytitanates. • The conductivity varies from 5 × 10−2 to 10−6–10−7 Sm/m in a wide range of temperatures. - Abstract: Titanates of alkali metals are widely applied materials as they are relatively low in cost and might be easily synthesized. They are utilized as adsorbents, catalysts, solid state electrolytes, superconductors. Here we report our results on electrical properties of the compacted amorphous potassium polytitanates powders. The electrical properties of the compacts were studied by means of complex impedance spectroscopy in a wide range of frequencies at different temperatures using two-electrode configuration. The frequency dependences of conductivity for the investigated potassium polytitanates compacts varies in the range from 5 × 10−2 Sm/m (high frequencies, ion conductivity) up to 10−6–10−7 Sm/m (low frequencies, electron conductivity) for a wide range of temperatures (19–150 °C). According to the results, at low frequencies quasi-static permittivity of the stabilized PPT compacts achieves high values of 104–105. This might be explained by Maxwell–Wagner polarization attributed to the layered structure of the potassium polytitanates particles containing potassium and hydronium ions together with crystallization water in the interlayer and is very promising for solid state electrolyte applications for moderate temperatures

  11. Potassium leakage and maize seed physiological potential

    Directory of Open Access Journals (Sweden)

    Miguel Mariane Victorio de Carvalho

    2002-01-01

    Full Text Available Seed production usually requires fast decisions to improve the efficacy of seed handling during harvesting, processing and storage. Seed technologists have focused on the development or improvement of procedures which allow rapid and consistent identification of higher quality seed lots. This research verified the effectiveness of the potassium leachate test on the evaluation of the physiological potential of maize seeds in comparison to recommended seed vigor tests. Five seed lots of the hybrid Avant were submitted to the potassium leachate, standard germination, first count, accelerated aging, electrical conductivity, field emergence and cold tests. The amount of potassium leachate was determined after seed imbibition for 30, 60, 90, 120, 150 and 180 minutes, at 25°C; a flame photometer adjusted to 50 mug K+ mL-1 pattern and reading 50 was used to determine the amount of leached potassium. The potassium leachate test consistently ranked the seed lots according to their physiological quality in comparison to other tests, and is a new alternative test for maize seed quality control programs.

  12. Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.

    Science.gov (United States)

    Henrickson, Charles H.; Robinson, Paul R.

    1979-01-01

    The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)

  13. Hydration of calcium sulfoaluminate cements - Experimental findings and thermodynamic modelling

    International Nuclear Information System (INIS)

    Calcium sulfoaluminate cements (CSA) are a promising low-CO2 alternative to ordinary Portland cements and are as well of interest concerning their use as binder for waste encapsulation. In this study, the hydration of two CSA cements has been investigated experimentally and by thermodynamic modelling between 1 h and 28 days at w/c ratios of 0.72 and 0.80, respectively. The main hydration product of CSA is ettringite, which precipitates together with amorphous Al(OH)3 until the calcium sulfate is consumed after around 1-2 days of hydration. Afterwards, monosulfate is formed. In the presence of belite, straetlingite occurs as an additional hydration product. The pore solution analysis reveals that straetlingite can bind a part of the potassium ions, which are released by the clinker minerals. The microstructure of both cements is quite dense even after 16 h of hydration, with not much pore space available at a sample age of 28 days. The pore solution of both cements is dominated during the first hours of hydration by potassium, sodium, calcium, aluminium and sulfate; the pH is around 10-11. When the calcium sulfate is depleted, the sulfate concentration drops by a factor of 10. This increases pH to around 12.5-12.8. Based on the experimental data, a thermodynamic hydration model for CSA cements based on cement composition, hydration kinetics of clinker phases and calculations of thermodynamic equilibria by geochemical speciation has been established. The modelled phase development with ongoing hydration agrees well with the experimental findings.

  14. Constant change: dynamic regulation of membrane transport by calcium signalling networks keeps plants in tune with their environment.

    Science.gov (United States)

    Kleist, Thomas J; Luan, Sheng

    2016-03-01

    Despite substantial variation and irregularities in their environment, plants must conform to spatiotemporal demands on the molecular composition of their cytosol. Cell membranes are the major interface between organisms and their environment and the basis for controlling the contents and intracellular organization of the cell. Membrane transport proteins (MTPs) govern the flow of molecules across membranes, and their activities are closely monitored and regulated by cell signalling networks. By continuously adjusting MTP activities, plants can mitigate the effects of environmental perturbations, but effective implementation of this strategy is reliant on precise coordination among transport systems that reside in distinct cell types and membranes. Here, we examine the role of calcium signalling in the coordination of membrane transport, with an emphasis on potassium transport. Potassium is an exceptionally abundant and mobile ion in plants, and plant potassium transport has been intensively studied for decades. Classic and recent studies have underscored the importance of calcium in plant environmental responses and membrane transport regulation. In reviewing recent advances in our understanding of the coding and decoding of calcium signals, we highlight established and emerging roles of calcium signalling in coordinating membrane transport among multiple subcellular locations and distinct transport systems in plants, drawing examples from the CBL-CIPK signalling network. By synthesizing classical studies and recent findings, we aim to provide timely insights on the role of calcium signalling networks in the modulation of membrane transport and its importance in plant environmental responses. PMID:26139029

  15. Application of electrophoresis of chlorine in the treatment of plantar fasciitis (prominent heel.

    Directory of Open Access Journals (Sweden)

    Filatova E.V.

    2014-12-01

    Full Text Available Aim: to determine the effectiveness of electrophoresis of chlorine in the treatment of patients with plantar fasciitis. Material and methods. Survey and treatment of 40 patients in out-patient treatment at a private medical clinic OOO «ЛЭЙТОНС» ("LEYTONS, LLC" of 45-65 years with "heel spur" (4 men and 36 women. Age of the disease varied from 6 months to several years. All patients' diagnosis was confirmed radiographically. Before and after the treatment there were tests: Visual analogue scale (VAS (scale from 0 to 100 points and dynamic test WAM, defines psychological component of pathology. Results: patients were divided into 3 groups according to type of therapy. In 1-St group was held on the heels of hydrocortisone phonophoresis, in the 2nd group of shock wave therapy; in 3rd group held electrophoresis 5% solution of calcium chloride on the heel with the cathode. In the 1st group pain after the treatment group stopped at 80% of the patients; in the group 2, with 83%; in the group 377% of the patients. Conclusion. Our study showed that the chlorine electrophoresis in patients with plantar fasciitis can be a choice in complex rehabilitation. Identification of adverse effects of therapy confirms the need for an integrated approach to treating patients with this pathology.

  16. Potassium permanganate ingestion as a suicide attempt

    Directory of Open Access Journals (Sweden)

    Tuba Cimilli Ozturk

    2012-01-01

    Full Text Available Potassium permanganate is a highly corrosive, water-soluble oxidizing antiseptic. A 68- year-old female patient was admitted to our Emergency Department after ingestion of 3 tablets of 250 mg potassium permanganate as a suicide attempt. The physical exam revealed brown stained lesions in the oropharynx. Emergency endoscopy was performed by the gastroenterologist after the third hour of ingestion. Emergency endoscopy revealed multiple superficial (Grade I-II lesions on the esophagus and cardia, which were considered secondary to the caustic substance. The mainstay in the treatment of potassium permanganate is supportive and the immediate priority is to secure the airway. Emergency endoscopy is an important tool used to evaluate the location and severity of injury to the esophagus, stomach and duodenum after caustic ingestion. Patients with signs and symptoms of intentional ingestion should undergo endoscopy within 12 to 24 h to define the extent of the disease.

  17. Emission infrared spectra of molten potassium heptafluoroniobate

    Energy Technology Data Exchange (ETDEWEB)

    Agulyanskij, A.I.; Bessonova, V.A. (AN SSSR, Apatity. Kol' skij Filial)

    1984-01-01

    Emission infrared spectra of potassium heptafluoroniobate molten in the air, vacuum and inert gas atmosphere are obtained. The analysis of different sections of the in got as well as potassium heptafluoroniobate condensate obtained upon long remelting in the air has shown that the investigated phases have complex composition. Along with the heptafluoroniobate potassium oxyfluoroniobate, mainly K/sub 2/NbOF/sub 5/ is present in them, in case of condensate-KNbOF/sub 4/. The pyrohydrolysis process consists of two-mutually compensating each other stages, that is parallel to the oxyfluoroniobate production the process of their destruction and partial removal from the melting surface takes place. It is shown that hydrogen fluoride produced as a result of KNbF/sub 5/ pyrohydrolysis can affect to considerable extent the ion structure of the melt.

  18. Potassium Permanganate Poisoning: A Nonfatal Outcome.

    Science.gov (United States)

    Eteiwi, Suzan M; Al-Eyadah, Abdallah A; Al-Sarihin, Khaldon K; Al-Omari, Ahmad A; Al-Asaad, Rania A; Haddad, Fares H

    2015-07-01

    Acute poisoning by potassium permanganate is a rare condition with high morbidity and mortality. Diagnosis of the condition relies on a history of exposure or ingestion and a high degree of clinical suspicion. Oxygen desaturation and the presence of methemoglobin are also helpful indicators. Since no specific antidote is available, treatment is mainly supportive. Few cases have been reported in the literature following potassium permanganate ingestion, whether intentional or accidental, and most of the patients in these cases had unfavorable outcomes, which was not the case in our patient. Our patient, a 73-year-old male, purchased potassium permanganate over the counter mistaking it for magnesium salt, which he frequently used as a laxative. Several hours after he ingested it, he was admitted to the endocrine department at King Hussein Medical Center, Jordan, with acute rapidly evolving shortness of breath. During hospitalization, his liver function tests deteriorated. Since he was diagnosed early and managed promptly he had a favorable outcome. PMID:26366264

  19. Some kinetics aspects of chlorine-solids reactions

    Energy Technology Data Exchange (ETDEWEB)

    Kanari, N.; Mishra, D.; Mochon, J.; Verdeja, L. F.; Diot, F.; Allain, E.

    2010-07-01

    The present paper describes detailed kinetics investigations on some selected chlorine-solid reactions through thermogravimetric measurements. The solids studied in this article include chemical pure oxides and sulfides as well as their natural bearing materials. The chlorinating agents employed are gaseous mixtures of Cl{sub 2}+N{sub 2} (chlorination), Cl{sub 2}+O{sub 2} (oxy chlorination), and Cl{sub 2}+CO (carbochlorination). Results are presented as effects of various parameters on the reaction rate of these solids with these chlorinating agents. It was observed that the reactivity of these solids towards different chlorinating agents varied widely. Sulfides could be chlorinated at room temperature, while carbochlorination of chromium (III) oxide was possible only above 500 degree centigrade. The variation of the chlorination rate of these complex materials with respect to gas velocity, composition and temperature enabled us to focus some light on the plausible reaction mechanisms and stoichiometries. The obtained results were used for selective removal of iron from chromite concentrates, extraction of valuable metals from sulfide materials, purification of MgO samples, etc.. (Author) 12 refs.

  20. Chlorine-heavy metals interaction on toxicity and metal accumulation

    International Nuclear Information System (INIS)

    The primary objectives of this study with rainbow trout (Salmo gairdneri) were: to determine whether acute toxic interaction of chlorine, nickel, and temperature is additive, synergistic, antagonistic, or if no interaction occurs; to provide a biological explanation of the mechanisms of the toxic interactions; and to develop a mortality model of the toxic interaction. Twenty chlorine-nickel toxicity tests and a bioaccumulation study, both with and without chlorine, were conducted to accomplish these objectives. Studies using 63Ni were conducted to monitor the effects of chlorine on nickel accumulation in the tissues of trout under conditions similar to those of multiple toxicant studies. The presence of 0.018 ppM TRC (total residual chlorine) increased nickel accumulation in tissues from fish exposed to chlorine and 63Ni. This may be due to an increase in the permeability of the gill to nickel during chlorine exposure. Chlorine and nickel had a synergistic toxic interaction. Mortality in these groups was significantly higher. Temperature did not influence toxicity as strongly

  1. Chlorine Dioxide Induced Multiple Chemical Sensitivity: MMPI Validity Problems.

    Science.gov (United States)

    Tentoni, Stuart C.

    This paper discusses Minnesota Multiphasic Personality Inventory (MMPI) data obtained from individuals exposed to chlorine dioxide in the workplace who developed Multiple Chemical Sensitivity Syndrome. The paper explores current research on chlorine dioxide exposed persons who were misdiagnosed on the basis of MMPI interpretations. Difficulties…

  2. UASB reactor effluent disinfection by ozone and chlorine

    NARCIS (Netherlands)

    Ribeiro da Silvia, G.H.; Bruning, H.; Gerrity, D.; Daniel, L.A.

    2015-01-01

    This research studied the sequential ozone and chlorine process with respect to, the inactivation of indicator bacteria and the formation of ozone disinfection byproducts in sanitary wastewater effluent. The applied ozone doses were 5, 8 and 10 mg.O3.L-1, followed by chlorine doses of 10, 20 and 30

  3. Chlorine-containing natural compounds in higher plants

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1986-01-01

    More than 130 chlorine-containing compounds have been isolated from higher plants and ferns; about half are polyacetylenes, thiophenes and sesquiterpene lactones from the Asteraceae. A chlorinated chlorophyll may be an important part of photosystem 1. High biological activity is found in 4...

  4. 78 FR 66767 - Chlorinated Isocyanurates From China and Japan

    Science.gov (United States)

    2013-11-06

    ... publishing the notice in the Federal Register of September 10, 2013 (78 FR 55293). The conference was held in... COMMISSION Chlorinated Isocyanurates From China and Japan Determinations On the basis of the record \\1... injured by reason of imports from China and Japan of chlorinated isocyanurates, provided for...

  5. CALCIUM SOAP LUBRICANTS

    OpenAIRE

    Alaz, Izer; Tugce, Nefise; Devrim, Balköse

    2014-01-01

    The article studies the properties of calcium stearate (CaSt2) and lubricants produced on its basis. These lubricants were prepared using sodium stearate and calcium chloride by subsidence from aqueous solutions. The CaSt2 and the light fraction of crude oil were mixed together to obtain lubricating substances. The article shows that CaSt2 had the melting temperature of 142.8 C that is higher than the melting temperature of crude oil (128 C). The compositions of obtained lubricants were stu...

  6. Biodegradability of Chlorinated Anilines in Waters

    Institute of Scientific and Technical Information of China (English)

    CHAO WANG; GUAN-GHUA LU; YAN-JIE ZHOU

    2007-01-01

    Objective To identify the bacteria tolerating chlorinated anilines and to study the biodegradability of o-chloroaniline and its coexistent compounds. Methods Microbial community of complex bacteria was identified by plate culture observation techniques and Gram stain method. Bacterial growth inhibition test was used to determine the tolerance of complex bacteria to toxicant. Biodegradability of chlorinated anilines was determined using domesticated complex bacteria as an inoculum by shaking-flask test. Results The complex bacteria were identified, consisting of Xanthomonas, Bacillus alcaligenes,Acinetobacter, Pseudomonas, and Actinomycetaceae nocardia. The obtained complex bacteria were more tolerant to o-chloroaniline than mixture bacteria in natural river waters. The effects of exposure concentration and inoculum size on the biodegradability of o-chloroaniline were analyzed, and the biodegradation characteristics of single o-chloroaniline and 2,4-dichloroaniline were compared with the coexistent compounds. Conclusion The biodegradation rates can be improved by decreasing concentration of compounds and increasing inoculum size of complex bacteria. When o-chloroaniline coexists with aniline, the latter is biodegraded prior to the former, and as a consequence the metabolic efficiency of o-chloroaniline is improved with the increase of aniline concentration. Meanwhile, when o-chloroaniline coexists with 2,4-dichloroaniline, the metabolic efficiency of 2,4-dichloroaniline is markedly improved.

  7. New infrared spectroscopic database for chlorine nitrate

    International Nuclear Information System (INIS)

    Fourier transform infrared measurements of chlorine nitrate have been performed in the spectral region 500-1330 cm-1 at 0.002-0.008 cm-1 spectral resolution. Absorption cross sections were derived from 23 spectra covering the temperature range from 190 to 296 K and air pressure range from 0 to 150 hPa. For line-by-line analysis, further spectra were recorded at 0.00094 cm-1 spectral resolution at 190 and 296 K. The sample was synthesized from N2O5 and Cl2O. Number densities in the absorption cell were derived from pressure measurements of the purified sample. Quality assurance included measurements with different sample pressures, spectroscopic purity check of the sample, comparison of integrated absorption cross sections over entire band systems, and assessment of residuals from remote-sensing retrievals. Multiplicative and additive errors were considered giving an overall uncertainty of +2.5/-3.5%. Further data reduction was achieved with an interpolation scheme based on two-dimensional polynomials in ln(pressure) and temperature. The worst-case error for the interpolated data is +4.5/-5.5%. The database is well-suited for remote-sensing application and should reduce the atmospheric chlorine nitrate error budget substantially

  8. Studies of potassium-promoted nickel catalysts for methane steam reforming: Effect of surface potassium location

    Science.gov (United States)

    Borowiecki, Tadeusz; Denis, Andrzej; Rawski, Michał; Gołębiowski, Andrzej; Stołecki, Kazimierz; Dmytrzyk, Jaromir; Kotarba, Andrzej

    2014-05-01

    The effect of potassium addition to the Ni/Al2O3 steam reforming catalyst has been investigated on several model systems, including K/Al2O3 with various amounts of alkali promoters (1-4 wt% of K2O), a model catalyst 90%NiO-10%Al2O3 promoted with potassium and a commercial catalyst. The potassium surface state and stability were investigated by means of the Species Resolved Thermal Alkali Desorption method (SR-TAD). The activity of the catalysts in the steam reforming of methane and their coking-resistance were also evaluated. The results reveal that the beneficial effect of potassium addition is strongly related to its location in the catalysts. The catalyst surface should be promoted with potassium in order to obtain high coking-resistant catalysts. Moreover, the catalyst preparation procedure should ensure a direct interaction of potassium with the Al2O3 support surface. Due to the low stability of potassium on θ-Al2O3 this phase is undesirable during the preparation of a stable steam reforming catalyst.

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

    Science.gov (United States)

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

  10. Release of chlorine from biomass at gasification conditions

    International Nuclear Information System (INIS)

    The objective of the project was to investigate the influence of different gasifying atmospheres on the release of chlorine from biomass during gasification conditions. Furthermore, the purpose was also to try and identify the formed chloro compounds. The results showed that O2, H2O and CO2 had negligible effect on the chlorine release at temperatures under 700 deg C. At temperatures above 800 deg C the reactivity towards CO2 increased and could be seen as higher chlorine release and less solid residue. No chloro organic compounds (aliphatic one to six carbons or aromatic one to two rings) could be detected in the tar or the fuel gas produced during pyrolysis/gasifying. On the other hand, comparable amounts of chlorinated benzenes were found in the cooling section during combustion of lucerne and of synthetic waste, indicating that oxygen is essential for chlorination reactions. 11 refs, 4 figs, 1 tab

  11. Effect of Pomegranate Juice on Bone Calcium Content and Body Weight of

    OpenAIRE

    Fatemeh Parvin; Malihezaman Monsefi; Tahereh Talaei-Khozani

    2014-01-01

    Background: Pomegranate juice has several antioxidant components such as flavenoids and mineral materials such as sodium and potassium. In this study the effects of pomegranate juice on bone calcium content and body weight of adult mice were survived. Materials and Methods: In this applied study two doses (3.3 and 6.6 ml/kg) of pomegranate juice (PJ) were gavaged to female mice for 30 days. Animals were weighed at days of 0, 5, 10, 15, 20, 25 and 30. Bone calcium contents were measured by ...

  12. Minerals to dairy cows with focus on calcium and magnesium balance

    OpenAIRE

    Kronqvist, Cecilia

    2011-01-01

    Both clinical and subclinical deficiency of calcium and magnesium may cause problems in dairy cows. Clinical hypocalcaemia most commonly occurs at calving and onset of lactation and is associated with milk fever, while clinical hypomagnesaemia occurs under certain dietary conditions. Factors affecting the calcium and magnesium status in dairy cows were examined in this thesis. The effect of dietary magnesium (0.19 and 0.43 % of dry matter) and potassium (1.9, 2.8, and 3.7 % of dry matter)...

  13. Separation of plutonium from sulphate bearing analytical waste by co-precipitation with calcium oxalate

    International Nuclear Information System (INIS)

    A simple approach for separation of Plutonium from sulfate bearing Analytical waste is presented here. The analytical waste is generated during analysis of plutonium using the Drummond-Grand potentiometric method mainly contains sulphate ions. The removal and recovery of plutonium from this waste is important due to radio toxicity associated with it as well as its strategic importance. Plutonium is co-precipitated with calcium oxalate by calcium nitrate and potassium oxalate mixture. The recovery is almost complete (99.96%). This method is adapted for routine use in our laboratory. (author)

  14. Molecular Interactions between Tarantula Toxins and Low-Voltage-Activated Calcium Channels

    OpenAIRE

    Autoosa Salari; Benjamin S. Vega; Milescu, Lorin S.; Mirela Milescu

    2016-01-01

    Few gating-modifier toxins have been reported to target low-voltage-activated (LVA) calcium channels, and the structural basis of toxin sensitivity remains incompletely understood. Studies of voltage-gated potassium (Kv) channels have identified the S3b–S4 “paddle motif,” which moves at the protein-lipid interface to drive channel opening, as the target for these amphipathic neurotoxins. Voltage-gated calcium (Cav) channels contain four homologous voltage sensor domains, suggesting multiple t...

  15. Calcium silicate hydrates: Solid and liquid phase composition

    International Nuclear Information System (INIS)

    This paper presents a review on the relationship between the composition, the structure and the solution in which calcium silicate hydrate (C–S–H) is equilibrated. The silica chain length in C–S–H increases with the silicon concentration and the calcium content in the interlayer space with the calcium concentrations. Sodium and potassium are taken up in the interlayer space, preferentially at low calcium concentrations and thus by low Ca/Si C–S–H. Aluminium uptake in C–S–H increases strongly at higher aluminium concentrations in the solution. At low Ca/Si, aluminium substitutes silica in the bridging position, at Ca/Si > 1 aluminium is bound in TAH. Recently developed thermodynamic models are closely related to the structure of C–S–H and tobermorite, and able to model not only the solubility and the chemical composition of the C–S–H, but also to predict the mean silica chain length and the uptake of aluminium

  16. Calcium silicate hydrates: Solid and liquid phase composition

    Energy Technology Data Exchange (ETDEWEB)

    Lothenbach, Barbara, E-mail: Barbara.lothenbach@empa.ch [Laboratory Concrete & Construction Chemistry, Empa (Switzerland); Nonat, André [ICB, UMR CNRS 6303 CNRS-Université de Bourgogne, Faculté des Sciences et Techniques, BP47870, 21078 Dijon Cedex (France)

    2015-12-15

    This paper presents a review on the relationship between the composition, the structure and the solution in which calcium silicate hydrate (C–S–H) is equilibrated. The silica chain length in C–S–H increases with the silicon concentration and the calcium content in the interlayer space with the calcium concentrations. Sodium and potassium are taken up in the interlayer space, preferentially at low calcium concentrations and thus by low Ca/Si C–S–H. Aluminium uptake in C–S–H increases strongly at higher aluminium concentrations in the solution. At low Ca/Si, aluminium substitutes silica in the bridging position, at Ca/Si > 1 aluminium is bound in TAH. Recently developed thermodynamic models are closely related to the structure of C–S–H and tobermorite, and able to model not only the solubility and the chemical composition of the C–S–H, but also to predict the mean silica chain length and the uptake of aluminium.

  17. Potassium fertilization for pineapple: effects on soil chemical properties and plant nutrition

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Junqueira Teixeira

    2011-06-01

    Full Text Available A field experiment was carried out on an Ultisol located at the city of Agudos (22º30'S; 49º03'W, in the state of São Paulo, Brazil, in order to determine the effects of rates and sources of potassium fertilizer on nutritional status of 'Smooth Cayenne' pineapple and on some soil chemical properties. The experiment was a complete factorial design with four rates (0, 175, 350, and 700 kg ha-1 of K2O and three combinations of K sources (100% KCl, 100% K2SO4 and 40% K2SO4 + 60% KCl. Soil samples were taken from the depths 0-20 cm, 20-40 cm and 40-60 cm at planting and 14 months after. Nutritional status of pineapple plants was assessed by means of tissue analysis. Soil K availability increased with application of K fertilizer, regardless of K sources. Soil chlorine and Cl concentration in pineapple leaves increased with application of KCl or K2SO4+KCl. Plant uptake of potassium was shaped by soil K availability and by the application rates of K fertilizer, independently of K sources.

  18. Phase-transfer catalysis applied to the oxidation of nonaqueous phase trichloroethylene by potassium permanganate

    Science.gov (United States)

    Seol, Yongkoo; Schwartz, Franklin W.

    2000-07-01

    The use of potassium permanganate to oxidize chlorinated solvents has been demonstrated as an effective process for treating nonaqueous phase liquids in ground-water systems. This study evaluates the effectiveness of phase-transfer catalysts (PTCs) in enhancing the degradation rate. PTCs work by transferring permanganate ion into the nonaqueous phase where it initiates oxidative decomposition. We studied the oxidation of trichloroethylene (TCE) by potassium permanganate, conducting kinetic batch experiments in conjunction with three PTCs that varied in terms of their extraction constants and molecular structures. Using the same batch technique, we examined whether PTCs could enhance the aqueous solubility of TCE. Solubilization could also increase oxidation rates in the aqueous phase. Rates of TCE oxidation in solutions containing the PTCs and a blank were estimated separately by measuring chloride concentration and UV-Vis absorbance in the aqueous phase. The enhanced rate of TCE destruction by the PTCs was reflected by an increase in the rate of consumption of permanganate ion and production of chloride ion. There was no tendency for the PTCs, however, to solubilize TCE in the aqueous phase. Therefore, the PTCs increased the rate of TCE decomposition by catalyzing permanganate oxidation in the organic phase. This study suggests that there is significant potential for testing this scheme under field conditions.

  19. A sensor for calcium uptake

    OpenAIRE

    Collins, Sean; Meyer, Tobias

    2010-01-01

    Mitochondria — the cell’s power plants — increase their energy production in response to calcium signals in the cytoplasm. A regulator of the elusive mitochondrial calcium channel has now been identified.

  20. Children's Bone Health and Calcium

    Science.gov (United States)

    ... Trials Resources and Publications Children's Bone Health and Calcium: Condition Information Skip sharing on social media links ... straight, walk, run, and lead an active life. Calcium is one of the key dietary building blocks ...

  1. Effects of chlorine or chlorine dioxide during immersion chilling on recovery of bacteria from broiler carcasses and chiller water

    Science.gov (United States)

    A study was conducted to determine the microbiological impact of immersion chilling broiler carcasses with chlorine or chlorine dioxide. Eviscerated, pre-chill commercial broiler carcasses were cut into left and right halves along the keel bone, and each half was rinsed (HCR) in 100 mL of 0.1% pept...

  2. Calcium ion channel and epilepsy

    Institute of Scientific and Technical Information of China (English)

    Yudan Lü; Weihong Lin; Dihui Ma

    2006-01-01

    OBJECTIVE: To review the relationship between calcium ion channel and epilepsy for well investigating the pathogenesis of epilepsy and probing into the new therapeutic pathway of epilepsy.DATA SOURCES: A computer-based online research Calcium ion channel and epilepsy related articles published between January 1994 and December 2006 in the CKNI and Wanfang database with the key words of "calcium influxion, epilepsy, calcium-channel blocker". The language was limited to Chinese. At the same time,related articles published between January 1993 and December 2006 in Pubmed were searched for on online with the key words of "calcium influxion, epilepsy" in English.STUDY SELECTION: The materials were selected firstly. Inclusive criteria: ① Studies related to calcium ion channel and the pat1hogenesis of epilepsy. ② Studies on the application of calcium ion channel blocker in the treatment of epilepsy. Exclusive criteria: repetitive or irrelated studies.DATA EXTRACTION: According to the criteria, 123 articles were retrieved and 93 were excluded due to repetitive or irrelated studies. Altogether 30 articles met the inclusive criteria, 11 of them were about the structure and characters of calcium ion channel, 10 about calcium ion channel and the pathogenesis of epilepsy and 9 about calcium blocker and the treatment of epilepsy.DATA SYNTHESIS: Calcium ion channels mainly consist of voltage dependent calcium channel and receptor operated calcium channel. Depolarization caused by voltage gating channel-induced influxion is the pathological basis of epileptic attack, and it is found in many studies that many anti-epileptic drugs have potential and direct effect to rivalizing voltage-dependent calcium ion channel.CONCLUSION: Calcium influxion plays an important role in the seizure of epilepsy. Some calcium antagonists seen commonly are being tried in the clinical therapy of epilepsy that is being explored, not applied in clinical practice. If there are enough evidences to

  3. Synergetic Inactivation of Microorganisms in Drinking Water by Short-term Free Chlorination and Subsequent Monochloramination

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To introduce synergetic inactivation of microorganisms in drinking water by short-term free chlorination for less than 15 minutes followed by monochloramination. Methods Indicator microorganisms such as Escherichia coli,Staphylococcus aureus, Candida albicans, and spores of Bacillus subtilis were used to assess the efficiency of sequential chlorination and free chlorination. Results The sequential chlorination was more efficient in inactivating these microorganisms than free chlorination, indicating that synergy was provided by free chlorine and monochloramine. Ammonia addition time, temperature and pH had influences on this synergy. Conclusion The possible mechanism of this synergy might involve three aspects: free chlorine causing sublethal injury to microorganisms and monochloramine further inactivating them; different ability of free chlorine and monochloramine to penetrate and inactivate microorganism congeries; and higher concentration of residual chlorine in sequential chlorination than in free chlorination.

  4. Solar Imagery - Chromosphere - Calcium

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of full-disk images of the sun in Calcium (Ca) II K wavelength (393.4 nm). Ca II K imagery reveal magnetic structures of the sun from about...

  5. Voltage-dependent calcium channels in skeletal muscle transverse tubules. Measurements of calcium efflux in membrane vesicles

    International Nuclear Information System (INIS)

    Transverse tubule membranes isolated from rabbit skeletal muscle consist mainly of sealed vesicles that are oriented primarily inside out. These membranes contain a high density of binding sites for 1,4-dihydropyridine calcium channel antagonists. The presence of functional voltage-dependent calcium channels in these membranes has been demonstrated by their ability to mediate 45Ca2+ efflux in response to changes in membrane potential. Fluorescence changes of the voltage-sensitive dye, 3,3'-dipropyl-2,2'-thiadicarbocyanine, have shown that transverse tubule vesicles may generate and maintain membrane potentials in response to establishing potassium gradients across the membrane in the presence of valinomycin. A two-step procedure has been developed to measure voltage-dependent calcium fluxes. Vesicles loaded with 45Ca2+ are first diluted into a buffer designed to generate a membrane potential mimicking the resting state of the cell and to reduce the extravesicular Ca2+ to sub-micromolar levels. 45Ca2+ efflux is then measured upon subsequent depolarization. Flux responses are modulated with appropriate pharmacological specificity by 1,4-dihydropyridines and are inhibited by other calcium channel antagonists such as lanthanum and verapamil

  6. Impregnating Coal With Calcium Carbonate

    Science.gov (United States)

    Sharma, Pramod K.; Voecks, Gerald E.; Gavalas, George R.

    1991-01-01

    Relatively inexpensive process proposed for impregnating coal with calcium carbonate to increase rates of gasification and combustion of coal and to reduce emission of sulfur by trapping sulfur in calcium sulfide. Process involves aqueous-phase reactions between carbon dioxide (contained within pore network of coal) and calcium acetate. Coal impregnated with CO2 by exposing it to CO2 at high pressure.

  7. Acidosis and Urinary Calcium Excretion

    DEFF Research Database (Denmark)

    Alexander, R Todd; Cordat, Emmanuelle; Chambrey, Régine;

    2016-01-01

    Metabolic acidosis is associated with increased urinary calcium excretion and related sequelae, including nephrocalcinosis and nephrolithiasis. The increased urinary calcium excretion induced by metabolic acidosis predominantly results from increased mobilization of calcium out of bone and...... renal tubule and then discuss why not all gene defects that cause renal tubular acidosis are associated with hypercalciuria and nephrocalcinosis....

  8. Human immune interferon: induction in lymphoid cells by a calcium ionophore.

    OpenAIRE

    Dianzani, F; Monahan, T. M.; Georgiades, J; Alperin, J B

    1980-01-01

    Human lymphocyte cultures produced interferon after treatment with the calcium ionophore A23187, but not after treatment with potassium ionophore nonactin. Interferon production was detectable between 3 and 6 h after ionophore treatment and reached the maximum level between 12 and 24 h. Ionophore-induced interferon appeared to be immune interferon on the basis of acid lability, lack of neutralization by antibody to leukocyte interferon, slow kinetics of activation of the antiviral state, and ...

  9. Pharmacologic study of calcium influx pathways in rabbit aortic smooth muscle

    International Nuclear Information System (INIS)

    Functional characteristics and pharmacologic domains of receptor-operated and potential-sensitive calcium (Ca2+) channels (ROCs and PSCs, respectively) were derived via measurements of 45Ca2+ influx (M/sup Ca/) during activation by the neurotransmitters norepinephrine (NE), histamine (HS), and serotonin (5-HT) and by elevated extracellular potassium (K+) in the individual or combined presence of organic Ca2+ channel antagonists (CAts), calmodulin antagonists (Calm-ants), lanthanum (La3+), and agents that increase intracellular levels of cyclic AMP

  10. PCDD/F formation in an iron/potassium-catalyzed diesel particle filter.

    Science.gov (United States)

    Heeb, Norbert V; Zennegg, Markus; Haag, Regula; Wichser, Adrian; Schmid, Peter; Seiler, Cornelia; Ulrich, Andrea; Honegger, Peter; Zeyer, Kerstin; Emmenegger, Lukas; Bonsack, Peter; Zimmerli, Yan; Czerwinski, Jan; Kasper, Markus; Mayer, Andreas

    2013-06-18

    Catalytic diesel particle filters (DPFs) have evolved to a powerful environmental technology. Several metal-based, fuel soluble catalysts, so-called fuel-borne catalysts (FBCs), were developed to catalyze soot combustion and support filter regeneration. Mainly iron- and cerium-based FBCs have been commercialized for passenger cars and heavy-duty vehicle applications. We investigated a new iron/potassium-based FBC used in combination with an uncoated silicon carbide filter and report effects on emissions of polychlorinated dibenzodioxins/furans (PCDD/Fs). The PCDD/F formation potential was assessed under best and worst case conditions, as required for filter approval under the VERT protocol. TEQ-weighted PCDD/F emissions remained low when using the Fe/K catalyst (37/7.5 μg/g) with the filter and commercial, low-sulfur fuel. The addition of chlorine (10 μg/g) immediately led to an intense PCDD/F formation in the Fe/K-DPF. TEQ-based emissions increased 51-fold from engine-out levels of 95 to 4800 pg I-TEQ/L after the DPF. Emissions of 2,3,7,8-TCDD, the most toxic congener (TEF = 1.0), increased 320-fold, those of 2,3,7,8-TCDF (TEF = 0.1) even 540-fold. Remarkable pattern changes were noticed, indicating a preferential formation of tetrachlorinated dibenzofurans. It has been shown that potassium acts as a structural promoter inducing the formation of magnetite (Fe3O4) rather than hematite (Fe2O3). This may alter the catalytic properties of iron. But the chemical nature of this new catalyst is yet unknown, and we are far from an established mechanism for this new pathway to PCDD/Fs. In conclusion, the iron/potassium-catalyzed DPF has a high PCDD/F formation potential, similar to the ones of copper-catalyzed filters, the latter are prohibited by Swiss legislation. PMID:23713673

  11. Appraisal of chlorine contact tank modelling practices.

    Science.gov (United States)

    Rauen, William B; Angeloudis, Athanasios; Falconer, Roger A

    2012-11-15

    With new water directives imposing strict regulations to reduce the footprint of treatment operations and contaminant levels, a performance review of water treatment facilities, including Chlorine Contact Tanks (CCTs) is required. This paper includes a critical appraisal of the international literature on CCT modelling practices to date, aiming to assist the identification of areas requiring further development, in particular, relating to the computational modelling capability and availability of tools to assist hydraulic design and optimisation studies of CCTs. It notes that the hydraulic optimisation practice of poorly designed tanks commenced with experimental studies undertaken in the 1960s and 1970s, which involved mainly two types of studies, namely in situ tracer tests and laboratory physical modelling. The former has traditionally been conducted to diagnose the hydraulic performance of existing CCTs, typically based on results such as Residence Time Distribution (RTD) curves and values of the Hydraulic Efficiency Indicators (HEIs). The latter has been useful in trial and error testing of the impact of certain design modifications on those results, with suggestions for later improvements of the field scale unit. In the 1980s mathematical and numerical modelling studies started to be used to assist CCT investigations, offering a greater level of detail in a more cost-effective manner than equivalent experimentally based investigations. With the growth of computing power and the popularisation of computational models, the 1990s saw the development and application of Computational Fluid Dynamics (CFD) tools to simulate the hydraulic performance of CCTs, sometimes independently of experimentation, other than by using available data to calibrate and validate modelling predictions. This has led to the current scenario of CFD models being invaluable assistive tools in optimisation studies of CCTs, with the experimentation practice continuing to allow for specific

  12. Chlorine Isotopes: As a Possible Tracer of Fluid/Bio-Activities on Mars and a Progress Report on Chlorine Isotope Analysis by TIMs

    Science.gov (United States)

    Nakamura, N.; Nyquist, L.E.; Reese, Y.; Shih, C-Y.; Numata, M.; Fujitani, T.; Okano, O.

    2009-01-01

    Significantly large mass fractionations between chlorine isotopes (Cl-35, Cl-37) have been reported for terrestrial materials including both geological samples and laboratory materials. Also, the chlorine isotopic composition can be used as a tracer for early solar system processes. Moreover, chlorine is ubiquitous on the Martian surface. Typical chlorine abundances in Gusev soils are approx.0.5 %. The global surface average chlorine abundance also is approx.0.5 %. Striking variations among outcrop rocks at Meridiani were reported with some chlorine abundances as high as approx.2%. Characterizing conditions under which chlorine isotopic fractionation may occur is clearly of interest to planetary science. Thus, we have initiated development of a chlorine isotopic analysis technique using TIMS at NASA-JSC. We present here a progress report on the current status of development at JSC and discuss the possible application of chlorine isotopic analysis to Martian meteorites in a search for fluid- and possibly biological activity on Mars.

  13. Activation of KCNN3/SK3/KCa2.3 channels attenuates enhanced calcium influx and inflammatory cytokine production in activated microglia

    OpenAIRE

    Dolga, Amalia M.; Letsche, Till; Gold, Maike; Doti, Nunzianna; Bacher, Michael; Chiamvimonvat, Nipavan; Dodel, Richard; Culmsee, Carsten

    2012-01-01

    In neurons, small-conductance calcium activated potassium (KCNN/SK/KCa2) channels maintain calcium homeostasis after NMDA receptor activation, thereby preventing excitotoxic neuronal death. So far, little is known about the function of KCNN/SK/KCa2 channels in non-neuronal cells, such as microglial cells. In this study, we addressed the question whether KCNN/SK/KCa2 channels activation affected inflammatory responses of primary mouse microglial cells upon lipopolysaccharide (LPS) stimulation....

  14. Astrocytic Potassium Channels in CNS Disorders

    Czech Academy of Sciences Publication Activity Database

    Anděrová, Miroslava; Pivoňková, Helena

    New York : Nova Science Publishers, 2012 - (González-Pérez, O.), s. 17-36 ISBN 978-1-62081-585-4 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z50390703 Keywords : astroglia * potassium ion channels * CNS pathology Subject RIV: FH - Neurology

  15. Potassium - Multiple Languages: MedlinePlus

    Science.gov (United States)

    ... Chinese - Simplified (简体中文) Chinese - Traditional (繁體中文) Spanish (español) Chinese - Simplified (简体中文) Potassium Content of Common Foods (High) English 含高量钾质的食品(每份所含钾质多过200毫克) - 简体中文 (Chinese - Simplified) PDF ...

  16. Nutritional potassium requirement for laying Japanese quails

    Directory of Open Access Journals (Sweden)

    Fernando Guilherme Perazzo Costa

    2011-12-01

    Full Text Available The objective of this study was to evaluate the potassium requirement for laying Japanese quails. Two hundred and forty quails were distributed in a randomized block design, with five treatments and six replicates, with eight birds each. The treatments consisted of a basal diet deficient in potassium (K (2.50 g/kg, supplemented with potassium carbonate, to replace the inert, to reach levels of 2.50, 3.50, 4.50, 5.50 and 6.50 (g/kg of K in the diet. There was a quadratic effect of K levels on feed intake, egg production, egg mass and feed conversion per egg mass and per egg dozen, estimating the requirements of 4.26, 4.41, 4.38, 4.43 and 4.48 (g/kg of K diet, respectively. There was no significant effect on the levels of K in the diet on egg weight, albumen weight, percentage of yolk or shell and yolk color. However, yolk and shell weights reduced and the albumen percentage increased linearly with increasing levels of K in the diet. Despite the reduction of shell weight, the increased levels of K did not influence the specific gravity and shell thickness. The use of 4.41 g/kg of potassium is recommended in the diet for laying Japanese quails.

  17. Spectrophotometric Determination of Losartan Potassium in Tablets

    Directory of Open Access Journals (Sweden)

    Arianne Diane A. Aniñon

    2014-06-01

    Full Text Available In the quality control of pharmaceutical products, it is of utmost importance that validated analytical methods are used to ensure the credibility of the results generated. At the time of the study, official monographs from the United States Pharmacopeia and National Formulary (USP-NF for the quantification of Losartan potassium in tablets were unavailable, denoting the need for a validated analytical procedure for the analysis of the drug. The study adapted direct and first-derivative UV spectrophotometry methods proposed by Bonfilio and others (2010 for the assay of Losartan potassium in Losartan 50 mg. capsules, then modified and validated the said procedures for the assay of Losartan potassium in Losartan 100 mg. tablets following the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines on method validation for accuracy, precision, specificity, linearity, limit of detection, and limit of quantitation. Results demonstrated that all the performance characteristics of both methods were highly satisfactory and confirmed the possible application of the methods in routine analysis of Losartan potassium tablets.

  18. Hg(0) absorption in potassium persulfate solution.

    Science.gov (United States)

    Ye, Qun-feng; Wang, Cheng-yun; Wang, Da-hui; Sun, Guan; Xu, Xin-hua

    2006-05-01

    The aqueous phase oxidation of gaseous elemental mercury (Hg(0)) by potassium persulfate (KPS) catalyzed by Ag(+) was investigated using a glass bubble column reactor. Concentration of gaseous mercury and potassium persulfate were measured by cold vapor atom absorption (CVAA) and ion chromatograph (IC), respectively. The effects of pH value, concentration of potassium persulfate and silver nitrate (SN), temperature, Hg(0) concentration in the reactor inlet and tertiary butanol (TBA), free radical scavenger, on the removal efficiency of Hg(0) were studied. The results showed that the removal efficiency of Hg(0) increased with increasing concentration of potassium persulfate and silver nitrate, while temperature and TBA were negatively effective. Furthermore, the removal efficiency of Hg(0) was much better in neutral solution than in both acidic and alkaline solution. But the influence of pH was almost eliminated by adding AgNO(3). High Hg(0) concentration has positive effect. The possible reaction mechanism of gaseous mercury was also discussed. PMID:16615172

  19. 21 CFR 184.1635 - Potassium iodate.

    Science.gov (United States)

    2010-04-01

    ...) The ingredient meets the specifications of the “Food Chemicals Codex,” 3d Ed. (1981), pp. 245-246... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodate. 184.1635 Section 184.1635 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

  20. 21 CFR 184.1625 - Potassium citrate.

    Science.gov (United States)

    2010-04-01

    .... (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d ed. (1981), p. 242, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium citrate. 184.1625 Section 184.1625...