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1

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

E-print Network

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

Tas, A. Cuneyt

2

The crystal growth kinetics of alpha calcium sulfate hemihydrate in concentrated CaCl2-HCl solutions  

NASA Astrophysics Data System (ADS)

The crystal growth kinetics of calcium sulfate ?-hemihydrate (?-HH) in nearly constant supersaturated HCl-CaCl2 solutions were investigated. Two types of solutions were used, the first had a low HCl (1.4 mol/L) and high CaCl2 (2.8 mol/L) concentration and the second had a high HCl (5.6 mol/L) and low CaCl2 (0.7 mol/L) concentration. These conditions were chosen to represent the first and last stage of a newly developed stage-wise HCl regeneration process. The seeded growth experiments were carried out in a stirred, temperature controlled semi-batch reactor in which supersaturation was kept constant by simultaneous addition of CaCl2 and Na2SO4 solutions. The influence of the following parameters on ?-HH crystal growth was studied: temperature (70-95 °C), specific power input of stirring (0.02-1.29 W/kg) and equimolar inflow rate of CaCl2 and Na2SO4 (0-0.6 mol/h). The crystal growth rate was derived from particle size distribution measurements made with the laser light diffraction technique. It was found that the surface area normalized crystal growth rate increased linearly with the molar inflow rate up to 0.3 mol/h, at higher inflow rates no further increase of the growth rate was observed. Temperature and specific power input, within the investigated ranges, did not show a marked effect on the growth rate, attributable to a diffusion/adsorption controlled growth process. An interesting finding of the present research is the establishment of a positive relationship between the narrowing of the width of the particle size distribution with increasing crystal growth rate. The results show that the resulting particle size distribution is positively related to the reagent inflow rate, a finding that can be applied to the industrial design and scale-up of the ?-HH crystallization/HCl regeneration process.

Feldmann, Thomas; Demopoulos, George P.

2012-07-01

3

Influence of calcium chloride and ammonium thiosulfate on bermudagrass uptake of urea nitrogen  

Microsoft Academic Search

Calcium chloride (CaCl2) and ammonium thiosulfate (ATS) have demonstrated an ability to inhibit urea hydrolysis and NH3 volatilization. The objective of this experiment was to determine the effect of rainfall and soil drying on the ability of CaCl2 and ATS to increase bermudagrass nitrogen (N) uptake from surface?applied urea. Urea fertilizer, labeled with N and amended with CaCl2 or ATS,

J. J. Sloan; W. B. Anderson

1998-01-01

4

Start-Timing for Calcium Chloride Spray Programs Influences Fruit Calcium and Bitter Pit in ‘Braeburn’ and ‘Honeycrisp’ Apples  

Microsoft Academic Search

Early-season sprays of calcium chloride (CaCl2) have been reported to sometimes be more effective than later-season sprays for controlling bitter pit in apple (Malus × domestica Borkh.). We conducted a two-year study examining the influence of start-timing of CaCl2 spray programs on fruit Ca concentrations and at-harvest bitter pit incidence in ‘Braeburn’ and ‘Honeycrisp’ apples in Washington State, USA. Six

Frank J. Peryea; Gerry H. Neilsen; Dana Faubion

2007-01-01

5

Calcium chloride electron injection/extraction layers in organic electronic devices  

NASA Astrophysics Data System (ADS)

Nontoxic calcium chloride (CaCl2) was introduced into organic electronic devices as cathode buffer layer (CBL). The turn-on voltage and maximum luminance of organic light-emitting diode (OLED) with 1.5 nm CaCl2 was 3.5 V and 21 960 cd/m2, respectively. OLED with 1.5 nm CaCl2 possessed comparable electroluminescent characteristics to that of the commonly used LiF. Moreover, the performance of the organic photovoltaic device with 0.5 nm CaCl2 was comparable to that of the control device with LiF. Therefore, CaCl2 has the potential to be used as the CBL for organic electronic devices.

Qu, Bo; Gao, Zhi; Yang, Hongsheng; Xiao, Lixin; Chen, Zhijian; Gong, Qihuang

2014-01-01

6

The effects of HCl and CaCl(2) injections on intracellular calcium and pH in voltage-clamped snail (Helix aspersa) neurons.  

PubMed

To investigate the mechanisms by which low intracellular pH influences calcium signaling, I have injected HCl, and in some experiments CaCl(2), into snail neurons while recording intracellular pH (pH(i)) and calcium concentration ([Ca(2+)](i)) with ion-sensitive microelectrodes. Unlike fluorescent indicators, these do not increase buffering. Slow injections of HCl (changing pH(i) by 0.1-0.2 pH units min(-1)) first decreased [Ca(2+)](i) while pH(i) was still close to normal, but then increased [Ca(2+)](i) when pH(i) fell below 6.8-7. As pH(i) recovered after such an injection, [Ca(2+)](i) started to fall but then increased transiently before returning to its preinjection level. Both the acid-induced decrease and the recovery-induced increase in [Ca(2+)](i) were abolished by cyclopiazonic acid, which empties calcium stores. Caffeine with or without ryanodine lowered [Ca(2+)](i) and converted the acid-induced fall in [Ca(2+)](i) to an increase. Injection of ortho-vanadate increased steady-state [Ca(2+)](i) and its response to acidification, which was again blocked by CPA. The normal initial response to 10 mM caffeine, a transient increase in [Ca(2+)](i), did not occur with pH(i) below 7.1. When HCl was injected during a series of short CaCl(2) injections, the [Ca(2+)](i) transients (recorded as changes in the potential (V(Ca)) of the Ca(2+)-sensitive microelectrode), were reduced by only 20% for a 1 pH unit acidification, as was the rate of recovery after each injection. Calcium transients induced by brief depolarizations, however, were reduced by 60% by a similar acidification. These results suggest that low pH(i) has little effect on the plasma membrane calcium pump (PMCA) but important effects on the calcium stores, including blocking their response to caffeine. Acidosis inhibits spontaneous calcium release via the RYR, and leads to increased store content which is unloaded when pH(i) returns to normal. Spontaneous release is enhanced by the rise in [Ca(2+)](i) caused by inhibiting the PMCA. PMID:12356857

Thomas, Roger C

2002-10-01

7

Calcium chloride and ammonium thiosulfate as ammonia volatilization inhibitors for urea fertilizers  

Microsoft Academic Search

Surface?applied urea fertilizers are susceptible to hydrolysis and loss of nitrogen (N) through ammonium (NH3) volatilization when conditions favorable for these processes exist. Calcium chloride (CaCl2) and ammonium thiosulfate (ATS) may inhibit urease activity and reduce NH3 volatilization when mixed with urea fertilizers. The objective of this study was to evaluate the effectiveness of CaCl2 and ATS as urea?N loss

J. J. Sloan; W. B. Anderson

1995-01-01

8

Hydroxyapatite Mineralization on the Calcium Chloride Blended Polyurethane Nanofiber via Biomimetic Method  

Microsoft Academic Search

Polyurethane nanofibers containing calcium chloride (CaCl2) were prepared via an electrospinning technique for the biomedical applications. Polyurethane nanofibers with different concentration of CaCl2 were electrospun, and their bioactivity evaluation was conducted by incubating in biomimetic simulated body fluid (SBF) solution. The morphology, structure and thermal properties of the polyurethane\\/CaCl2 composite nanofibers were characterized by means of scanning electron microscopy (SEM),

R. Nirmala; Ki Taek Nam; R. Navamathavan; Soo-Jin Park; Hak Yong Kim

2011-01-01

9

Effects of binder and CaCl 2 contents on the strength of calcium carbide residue-fly ash concrete  

Microsoft Academic Search

This paper presents a concrete that utilizes a calcium carbide residue and fly ash mixture as the concrete binder instead of Portland cement. The ground calcium carbide residue (CR) was mixed with classified fly ash (FA) at a ratio of 30:70 (CR:FA) by weight and used as a binder to cast CR-FA concrete specimens. The effects of binder content, water

Nattapong Makaratat; Chai Jaturapitakkul; Charin Namarak; Vanchai Sata

2011-01-01

10

Electrochemical characteristics of uranium ions in calcium chloride hydrate melts  

NASA Astrophysics Data System (ADS)

Redox reactions of tetravalent uranium ion in calcium chloride hexahydrate CaCl2·6H2O melt ([CaCl2] = 6.9 M) were studied electrochemically and spectrophotometrically. Cyclic voltammograms in CaCl2·6H2O melt containing UCl4 were measured with a pyro-graphite carbon working electrode. A cathodic peak corresponding to the reduction of U4+ to U3+ was observed, and it was found to be controlled by the diffusion of U4+ in the melt. Although the concentration of H+ in the melt was negligible, the redox reaction of U4+ was observed without the disturbance of hydrolysis. The formal potential of the U4+|U3+ couple was determined to be -0.483 ± 0.005 V vs. NHE. The diffusion coefficient of U4+ in CaCl2·6H2O melt was determined to be 1.5 × 10-7 cm2 s-1 at 300 K. The anodic peak in the voltammogram was attributable to the oxidation of U4+ to UO22+, which was identified by using a technique based on the combination of electrolysis and spectrophotometry. Influences of the water content on chemical status of uranium ions in CaCl2 hydrate melts were studied.

Uehara, A.; Fujii, T.; Nagai, T.; Shirai, O.; Sato, N.; Yamana, H.

2010-03-01

11

AMELIORATIVE EFFECT OF CALCIUM CHLORIDE ON GROWTH, ANTIOXIDANT ENZYMES, PROTEIN PATTERNS AND SOME METABOLIC ACTIVITIES OF CANOLA (BRASSICA NAPUS L.) UNDER SEAWATER STRESS  

Microsoft Academic Search

The effect of calcium chloride (CaCl2) as an ameliorating agent on seawater stress was studied in canola (Brassica napus L.). Plants were raised in pots and exposed to seawater stress (30%) with or without 200 ppm CaCl2. Seawater-stressed plants showed decreased growth, water content, leaf area, photosynthetic pigments, total sugars, potassium (K), calcium (Ca), K\\/ sodium (Na) ratio and ascorbate

Arafat Abdel Hamed Abdel Latef

2011-01-01

12

Raman spectroscopic studies of chemical speciation in calcium chloride melts  

SciTech Connect

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

Windisch, Charles F.; Lavender, Curt A.

2005-02-01

13

Dose-dependent Response to an Intratesticular Injection of Calcium Chloride for Induction of Chemosterilization in Adult Albino Rats  

Microsoft Academic Search

This study concerned the minimum and optimum effective doses of calcium chloride needed for induction of chemosterilization in male albino rats, 30 days after a single intratesticular injection of calcium chloride (CaCl2.2H2O) solution at 2.5, 5, 10 or 20 mg per 100 g body weight per testis. There was a significant diminution in the relative wet weight of the sex

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

2002-01-01

14

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

Microsoft Academic Search

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

John J. Sloan; Warren B. Anderson

2001-01-01

15

Hydroxyapatite Mineralization on the Calcium Chloride Blended Polyurethane Nanofiber via Biomimetic Method.  

PubMed

Polyurethane nanofibers containing calcium chloride (CaCl2) were prepared via an electrospinning technique for the biomedical applications. Polyurethane nanofibers with different concentration of CaCl2 were electrospun, and their bioactivity evaluation was conducted by incubating in biomimetic simulated body fluid (SBF) solution. The morphology, structure and thermal properties of the polyurethane/CaCl2 composite nanofibers were characterized by means of scanning electron microscopy (SEM), field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetry. SEM images revealed that the CaCl2 salt incorporated homogeneously to form well-oriented nanofibers with smooth surface and uniform diameters along their lengths. The SBF incubation test confirmed the formation of apatite-like materials, exhibiting enhanced bioactive behavior of the polyurethane/CaCl2 composite nanofibers. This study demonstrated that the electrospun polyurethane containing CaCl2 composite nanofibers enhanced the in vitro bioactivity and supports the growth of apatite-like materials. PMID:21711574

Nirmala, R; Nam, Ki Taek; Navamathavan, R; Park, Soo-Jin; Kim, Hak Yong

2010-01-01

16

Human osteoblast cytotoxicity study of electrospun polyurethane/calcium chloride ultrafine nanofibers.  

PubMed

This work was focused on preparation and characterization of the polyurethane nanofibers containing calcium chloride (CaCl2) prepared via electrospinning process for the bionanotechnological applications. The morphological, structural characterizations and thermal properties of the polyurethane/CaCl2 nanofibers were determined by using scanning electron microscopy (SEM), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform-infrared (FT-IR) spectroscopy and thermogravimetry (TGA). SEM images revealed that these composite nanofibers were well-oriented and had good incorporation of CaCl2. The morphological feature of the cells attached on polyurethane/CaCl2 nanofibers scaffold was confirmed by SEM. The in vitro cell compatibility of the polyurethane/CaCl2 composite nanofibers was studied. This study demonstrated the non-toxic effect of electrospun polyurethane/CaCl2 composite nanofibers. Based on this, we propose a mechanism for the cell attachment. PMID:21770101

Nirmala, R; Kang, Hyung-Sub; El-Newehy, Mohamed H; Navamathavan, R; Park, Hye-Min; Kim, Hak Yong

2011-06-01

17

21 CFR 172.330 - Calcium pantothenate, calcium chloride double salt.  

...Calcium pantothenate, calcium chloride double salt. 172.330 Section 172.330 Food and...Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium pantothenate may be safely...

2014-04-01

18

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

Microsoft Academic Search

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

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

2005-01-01

19

Calcium/thionyl chloride battery technology  

NASA Astrophysics Data System (ADS)

This program is structured to develop both active and reserve configuration calcium-thionyl chloride electrochemical cells. The active configuration has required extensive work toward the storability on the calcium-anode in electrolyte solution. A variety of electrolyte salts have been screened in an effort to improve storage characteristics. The reserve configuration could lend itself to high temperature operation since calcium has such a high melting point when compared to lithium. Emphasis has been on the development of a high discharge rate cathode structure.

Higgins, R. I.; Potts, I.

1985-01-01

20

Development of a Novel Rabbit Model of Abdominal Aortic Aneurysm via a Combination of Periaortic Calcium Chloride and Elastase Incubation  

PubMed Central

Background The purpose of this study was to introduce a novel, simple and effective technique for creating a reliable rabbit model of abdominal aortic aneurysm (AAA) via a combination of periaortic calcium chloride (CaCl2) and elastase incubation. Methods Forty-eight New Zealand white rabbits were divided into four groups. The AAA model was developed via a 20-minute periaortic incubation of CaCl2 (0.5 mol/L) and elastase (1 Unit/µL) in a 1.5-cm aortic segment (Group CE). A single incubation of CaCl2 (Group C) or elastase (Group E) and a sham operation group (Sham Group) were used for the controls. Diameter was measured by serial digital subtraction angiography imaging on days 5, 15 and 30. Animals were sacrificed on day 5 and day 30 for histopathological and immunohistochemical studies. Results All animals in Group CE developed aneurysm, with an average dilation ratio of 65.3%±8.9% on day 5, 86.5%±28.7% on day 15 and 203.6%±39.1% on day 30. No aneurysm was found in Group C, and only one aneurysm was seen on day 5 in Group E. Group CE exhibited less intima-media thickness, endothelial recovery, elastin and smooth muscle cell (SMC) content, but stronger expression of matrix metalloproteinase-2, matrix metalloproteinase-9 and RAM11 compared to the controls. Conclusions The novel rabbit model of AAA created by using a combination of periaortic CaCl2 and elastase incubation is simple and effective to perform and is valuable for elucidating AAA mechanisms and therapeutic interventions in experimental studies. PMID:23844207

Xu, Ke; Zhang, Zhen; Qi, Xun; Xia, Yonghui; Ren, Ling

2013-01-01

21

Calcium/thionyl chloride battery technology  

NASA Astrophysics Data System (ADS)

This final report documents the development efforts conducted by the Lithium Batteries Group of the Couples Department of Eagle-Picher Industries. The objective of the project was to develop calcium-thionyl chloride cell technology. The original project was divided into two main tasks. Task One was to consist of component optimization and stability studies. Once sufficiently advanced, the ongoing results of Task One were to be integrated with Task Two. Task Two was to consist of demonstration of an optimized primary cell. In July, 1983, the program was redirected. Task Two was split, with effort to be directed toward both the original primary cell and toward a high discharge rate reserve configuration cell. Additional electrolyte salts were to be evaluated as a means of improving the storability of the active calcium-thionyl chloride cell.

Counts, T.

1985-12-01

22

CHLORIDE, IN CALCIUM, IN pH ARSENIC, IN  

E-print Network

CHLORIDE, IN CALCIUM, IN pH ARSENIC, IN MILLIGRAMS PER LITER MILLIGRAMS PER LITER MICROGRAMS PER concentrations, calcium concentrations, arsenic concentrations and pH after 100,000 years of simulated groundH ARSENIC, IN MILLIGRAMS PER LITER MILLIGRAMS PER LITER MICROGRAMS PER LITER #12;PHAST--A Program

23

The influence of magnetic fields on calcium carbonate precipitation  

Microsoft Academic Search

Laboratory experiments were undertaken to assess the effects of magnetic treatment on calcium carbonate precipitate. Static test solutions of calcium chloride, calcium sulphate and sodium carbonate were placed in a magnetic field. After magnetic treatment the solutions CaCl2\\/Na2CO3 and CaSO4\\/Na2CO3 were mixed and changes in precipitation recorded and compared with non-magnetised solutions. The results of this study support earlier work

Rebecca A Barrett; Simon A Parsons

1998-01-01

24

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

E-print Network

On-going research at Texas A&M University indicated that soil stabilization using calcium chloride filter cake along with Class F fly ash generates high strength. Previous studies were conducted with samples containing calcium chloride filter cake...

Choi, Hyung Jun

2006-10-30

25

New uses for calcium chloride solution as a mounting medium.  

PubMed

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

Herr, J M

1992-01-01

26

Dose-dependent response to an intratesticular injection of calcium chloride for induction of chemosterilization in adult albino rats.  

PubMed

This study concerned the minimum and optimum effective doses of calcium chloride needed for induction of chemosterilization in male albino rats, 30 days after a single intratesticular injection of calcium chloride (CaCl2.2H2O) solution at 2.5, 5, 10 or 20 mg per 100 g body weight per testis. There was a significant diminution in the relative wet weight of the sex organs (p<0.01), epididymal sperm count (p<0.001), plasma concentration of testosterone (p<0.01), testicular activities of delta5,3beta-hydroxy steroid dehydrogenase (delta5,3beta-HSD), 17beta-hydroxy steroid dehydrogenase (17beta-HSD) (p<0.01), glutathione S-transferase (GST) (p<0.01), superoxide dismutase (SOD) (p<0.01), and peroxidase (p<0.01), significant elevations in testicular content of malondialdehyde (MDA) and conjugated dienes (p<0.01), along with derangement of seminiferous tubular architecture and degeneration of the Leydig cells in the testis and elevations in the concentrations in the plasma of LH and FSH (p<0.01), commencing at a dose of 5 mg, with the greatest effects at a dose of 20 mg. No significant alterations in these factors occurred at the dose of 2.5 mg in comparison to the control that received only the vehicle. There was no significant alteration in the plasma concentrations of prolactin (p>0.05), corticosterone (p>0.05) or fasting blood glucose or in the rectal temperature (p>0.05) at any of the doses relative to the control group, suggesting that this chemosterilizing procedure did not exert any chronic stress on the experimental animals. From these observations, it may be suggested that 5 mg should be considered as the minimum dose, and 10 mg or 20 mg as the optimum dose, whereas 2.5 mg was ineffective for induction of chemosterilization. There would seem to be little point in using more than 20 mg of calcium chloride for this purpose. Intratesticular injection of calcium chloride at an effective dose may be considered as an alternative to surgical castration. PMID:12507039

Jana, K; Samanta, P K; Ghosh, D

2002-12-01

27

Calcium phosphate stabilization of fly ash with chloride extraction.  

PubMed

Municipal solid waste incinerator by products include fly ash and air pollution control residues. In order to transform these incinerator wastes into reusable mineral species, soluble alkali chlorides must be separated and toxic trace elements must be stabilized in insoluble form. We show that alkali chlorides can be extracted efficiently in an aqueous extraction step combining a calcium phosphate gel precipitation. In such a process, sodium and potassium chlorides are obtained free from calcium salts, and the trace metal ions are immobilized in the calcium phosphate matrix. Moderate calcination of the chemically treated fly ash leads to the formation of cristalline hydroxylapatite. Fly ash spiked with copper ions and treated by this process shows improved stability of metal ions. Leaching tests with water or EDTA reveal a significant drop in metal ion dissolution. Hydroxylapatite may trap toxic metals and also prevent their evaporation during thermal treatments. Incinerator fly ash together with air pollution control residues, treated by the combined chloride extraction and hydroxylapatite formation process may be considered safe to use as a mineral filler in value added products such as road base or cement blocks. PMID:12003153

Nzihou, Ange; Sharrock, Patrick

2002-01-01

28

Antioxidant status affects color stability and tenderness of calcium chloride-injected beef.  

PubMed

The objectives of this study were to determine whether vitamin E supplementation influences color and tenderness of beef injected with calcium chloride. Market heifers (n = 12) were fed a standard finishing diet with minimal levels of vitamin E (NE group). Another 12 market heifers were fed the NE diet with the inclusion of 1,000 IU/d of DL-alpha-tocopherol per animal for the last 125 d on feed (E group). Animals were slaughtered after 125 d on the diets and upon reaching an ultrasound backfat thickness > 10 mm. Half of the longissimus muscles from each treatment group (NE and E) were pumped to 10% over the original weight with 250 mM CaCl2 (Ca) at 24 h postmortem. Remaining muscles (NE and E) were pumped to 10% over the original weight with water (NC) at 24 h postmortem. After equilibrating overnight, steaks (2.54 cm) were overwrapped with O2-permeable film and stored for 7 d after injection. Hunter "L," "a," and "b" values were obtained each day of storage. Trained panelists evaluated color on d 1, 4, and 7 after injection. 2-Thiobarbituric acid-reactive substances (TBARS) values were measured on d 1 and 7 after injection. Warner-Bratzler (W-B) shear force values and trained sensory panel evaluations at 1, 3, and 7 d after injection were obtained. Immunoblotting techniques were used to monitor the 30-kDa degradation product of troponin-T at 1, 3, and 7 d after injection. At 4 d after injection, E/Ca steaks were the least discolored (P < 0.05). The E/Ca steak TBARS values were not significantly different from values for NE/NC steaks at 7 d after injection, whereas NE/Ca steaks had greater (P < 0.05) TBARS values after 7 d following injection compared with all other groups. Treatment with Ca resulted in higher off-flavor scores (P < 0.05). The E/Ca samples had the most rapid tenderization and proteolysis of all treatment groups. Warner-Bratzler shear values were lower in the E/Ca samples than in the E/NC samples at 1, 3, and 7 d after injection (P < 0.05). No difference in shear force was noted between NE/Ca and NE/NC samples at any time point. No difference in sensory tenderness was noted between NE/Ca and NE/NC samples at 1 d after injection. However, Ca-injected samples (NE/Ca and E/Ca) were rated as being significantly more tender than their uninjected counterparts (NE/NC and E/NC) at 3 and 7 d after injection. Injection of CaCl2 may result in more rapid and immediate tenderization if beef from animals supplemented with vitamin E is used. Vitamin E incorporation into muscle tissue may potentiate the action of exogenously added calcium by protecting the calpains from oxidation. PMID:11263827

Harris, S E; Huff-Lonergan, E; Lonergan, S M; Jones, W R; Rankins, D

2001-03-01

29

Effects of calcium hydroxide and calcium chloride addition to bentonite in iron ore pelletization.  

PubMed

Pyrite ash is created as waste from the roasting of pyrite ores during the production of sulphuric acid. These processes generate great amounts of pyrite ash waste that is generally land filled. This creates serious environmental pollution due to the release of acids and toxic substances. Pyrite ash waste can be utilized in the iron production industry as a blast furnace feed to process this waste and prevent environmental pollution. The essential parameters affecting the pelletization process of pyrite ash were studied using bentonite as a binder. Experiments were then carried out using bentonite and a mixture of bentonite with calcium hydroxide and calcium chloride in order to make the bentonite more effective. The metallurgical properties of pyrite ash, bentonite, calcium hydroxide, calcium chloride, a mixture of these and sintered pellets were studied using X-ray analysis. The crushing strength tests were carried out to investigate the strength of pyrite ash waste pellets. The results of these analyses showed that pyrite ash can be agglomerated to pellets and used in the iron production industry as a blast furnace feed. The crushing strength of the pellets containing calcium hydroxide and calcium chloride in addition to bentonite was better than the strength of pellets prepared using only bentonite binder. PMID:17121116

Tugrul, Nurcan; Derun, Emek Moroydor; Pi?kin, Mehmet

2006-10-01

30

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

E-print Network

deficiency could be reduced by calcium spraying (Kader, 2002). However, there are few re- ports about effectsEffect of pre-harvest calcium chloride applications on fruit calcium level and post October 2013 Keywords: Papaya Anthracnose Calcium Disease incidence Disease severity a b s t r a c

Biggs, Alan R.

31

Uptake of chloride and carbonate ions by calcium monosulfoaluminate hydrate  

SciTech Connect

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

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

2012-08-15

32

Effects of postmortem calcium chloride injection on meat palatability traits of strip loin steaks from cattle supplemented with or without zilpaterol hydrochloride.  

PubMed

An experiment was conducted to determine the effects of zilpaterol hydrochloride mM supplementation (ZH; 8.3 mg/kg on a DM basis for 20 d) and calcium chloride injection [CaCl(2), 200 at 5% (wt/wt) at 72 h postmortem] on palatability traits of beef (Bos taurus) strip loin steaks. Select (USDA) strip loins were obtained from control (no ZH = 19) and ZH-supplemented carcasses (n = 20). Right and left sides were selected alternatively to serve as a control (no INJ) or CaCl(2)-injected (INJ) and stored at 4°C. Before injecting the subprimals (72 h postmortem), 2 steaks were cut for proximate, sarcomere length, and myofibrillar fragmentation index (MFI) analyses. At 7 d postmortem each strip loin was portioned into steaks, vacuum packaged, and aged for the appropriate period for Warner-Bratzler shear force (WBSF; 7, 14, 21, and 28 d postmortem), trained sensory analysis (14 and 21 d postmortem), purge loss (7 d), and MFI (3, 7, 14, 21, and 28 d postmortem). Results indicated steaks from both ZH supplementation and INJ had reduced WBSF values as days of postmortem aging increased. The WBSF values of ZH steaks were greater (P < 0.05) than no ZH steaks at each postmortem aging period. The INJ steaks had lower WBSF values (P < 0.05) than non-injected steaks. A greater percentage (91 vs. 71%) of steaks had WBSF values < 4.6 kg from steers with no ZH supplementation at 7 d postmortem, but the percentage did not differ (P > 0.05) due to ZH at 14, 21, or 28 d or due to INJ at any aging period. Trained panelists rated tenderness less in ZH steaks than steaks with no ZH at 14 d and 21 d. However, INJ improved (P < 0.05) the tenderness ratings and flavor intensity of the trained panelists, compared with their non-injected cohorts at 21 d. Zilpaterol hydrochloride supplementation reduced (P < 0.05) MFI values, but INJ resulted in greater (P < 0.05) MFI values compared with no INJ. Subprimals from ZH and INJ showed greater purge loss (P < 0.05). Although no interactions were found with ZH and CaCl(2), injecting USDA Select strip loins from ZH-fed cattle can help reduce the normal WBSF variation as it does in steaks from non-ZH-fed cattle. PMID:22851240

Rodas-González, A; Pflanzer, S B; Garmyn, A J; Martin, J N; Brooks, J C; Knobel, S M; Johnson, B J; Starkey, J D; Rathmann, R J; de Felicio, P E; Streeter, M N; Yates, D A; Hodgen, J M; Hutcheson, J P; Miller, M F

2012-10-01

33

Mineral Trioxide Aggregate Mixed with Normal Saline, Calcium Chloride or KY Jelly as Apical Plug in Simulated Open Apices: An In vitro Microleakage Study  

PubMed Central

Introduction: Mineral trioxide aggregate (MTA) mixed with normal saline has short working time, delayed setting time, and poor consistency when used as an apical plug. A preliminary study suggested that substituting normal saline with KY Jelly or 5% calcium chloride (CaCl2) as a vehicle expedites the setting time of MTA. The present in vitro study compared the microleakage of ProRoot MTA mixed with normal saline (MS) to that of ProRoot MTA mixed with KY Jelly and/or 5% CaCl2 in simulated canals with open apices. Materials and methods: Thirty six single-rooted extracted human teeth were cleaned and shaped with ProTaper rotary system to make 36 standardized artificially created open apices. Teeth were randomly divided into three experimental groups (n=10) and two control groups (n=3). In group 1, MTA was mixed with normal saline (MS) and placed into the canals to form 4 to 5 mm apical plugs. In group 2, MTA was mixed with 5% CaCl2 (MC) and in group 3, MTA was mixed with KY Jelly (MK). The other two groups served as positive and negative controls. The remaining canal spaces in the experimental groups were backfilled with thermoplasticized gutta-percha without sealer. Dye penetration and clearing was used to evaluate the sealing ability of each group. The samples were then examined under stereomicroscope to measure the microleakage of different MTA mixtures in mm. Data were statistically analyzed using One-Sample Kolmogorov-Smirnov test for determination of normal distribution and then by one-way ANOVA and Tukey’s tests to detect any significance. Results: Positive and negative controls responded as expected. The MS group showed the least mean dye penetration value. There was a significant difference between MS with other groups (P<0.05) but no difference was found between MC and MK groups. Conclusion: Within the limitations of this in vitro study, we can conclude that among these three vehicles, normal saline mixed with ProRoot MTA has the least amount of microleakage in canals with open apices. PMID:24396375

Mehrvarzfar, Payman; Akhavan, Hengameh; Ghasemi, Sara; Khodaei, Fatemeh; Tour Savadkouhi, Sohrab; Dianat, Omid

2014-01-01

34

Production of Titanium Powder by Sodiothermic Reduction in CaCl2 Molten Salts  

NASA Astrophysics Data System (ADS)

A new sodiothermic reduction process of TiO2 in CaCl2 melt was proposed aimed at fine Ti powder preparation. The chemical analysis and direct potentiometric methods were used to investigate the reaction pathway of sodiothermic reduction in CaCl2 melt. The as-prepared samples were characterized by X-ray diffraction and scanning electron microscopy. It was found that when reductant of Na was added into the CaCl2 melt, Ca2+ was reduced to Ca by Na and Ca dissolved in the CaCl2 melt. The whole melt would have the reducing power with dissolved Ca. Using this melt as a reaction medium, fine and uniform Ti powder with a purity of around 99 mass pct was successfully produced at 1173 K (900 °C). In addition, as the CaCl2 melt could dissolve about 20 mol pct CaO, it was found that the molar ratio of TiO2 and CaCl2 should be 1:20 to eliminate the by-product CaO from the reaction interface within the experimental period to continue the reduction.

Du, Chao; Wang, Zheng; Hou, Jungang; Jiao, Shuqiang; Zhu, Hongmin

2014-09-01

35

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

PubMed

This study describes the induction of chemosterilization in three groups each of six adult male Black Bengal goats at 30 days after a single bilateral intratesticular injection of a calcium chloride (CaCl(2), 2H(2)O) solution at the doses of 10, 20 or 40 mg/kg body weight/testis, always in a 2 ml volume of normal saline. Another one group of animals received only 2 ml of normal saline per testis as a control. The induction of chemosterilization was measured using relative testicular weight as well as histomorphological parameters including seminiferous tubular architecture and germ cell association in seminiferous tubules along with morphology of the interstitial space. Biochemical markers included activities of testicular Delta(5), 3beta-hydroxysteroid dehydrogenase (Delta(5), 3beta-HSD), 17beta-hydroxysteroid dehydrogenase (17beta-HSD), catalase, glutathione peroxidase (GPx), glutathione S-transferase (GST) and superoxide dismutase (SOD) as well as monitoring the level of testicular thiobarbituric acid reactive substances (TBARS), conjugated dienes and reduced glutathione (GSH) content along with plasma concentrations of testosterone, LH and FSH. Histomorphological measures of testes showed total necrosis of testicular tissue at 30 days after an injection of either 20 or 40 mg CaCl(2) along with fibrosis in seminiferous tubules and interstitial spaces. Infiltration of leucocytes was observed with the 40 mg dose. Disintegration of germ cell arrangement in seminiferous tubules and washing out of germ cells from the tubules were noted with the 10mg dose. Relative organ weights, plasma concentrations of testosterone, testicular activities of Delta(5), 3beta-HSD, 17beta-HSD, catalase, GPx, GST, and SOD and testicular contents of GSH all were declined. Increases occurred in testicular TBARS, conjugated dienes and plasma concentrations of LH and FSH with each of the treatments by comparison with the control group. Plasma concentrations of cortisol and fasting blood sugar level as well as packed cell volume (PCV) and total plasma protein were recorded to monitor the changes of chronic stress in the experimental animals. Changes in these parameters were not significant. An intratesticular injection of calcium chloride at specified doses could be a suitable method of sterilization in preference to surgical castration of goats. PMID:15721661

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

2005-03-01

36

Calcium Chloride in Neonatal Parenteral Nutrition: Compatibility Studies Using Laser Methodology  

PubMed Central

Introduction We have previously reported results of precipitation studies for neonatal parenteral nutrition solutions containing calcium chloride and sodium phosphate using visual methods to determine compatibility. The purpose of this study was to do further testing of compatibility for solutions containing calcium chloride using more sensitive methods. Methods Solutions of Trophamine (Braun Medical Inc, Irvine, CA) and Premasol (Baxter Pharmaceuticals, Deerfield, IL) were compounded with calcium chloride and potassium phosphate. Controls contained no calcium or phosphate. After incubation at 37° for 24 hours solutions without visual precipitation were analyzed to determine mean particle size using dynamic light scattering from a laser light source. Results Particle sizes were similar for control solutions and those without visual precipitation and a mean particle size <1000 nm. Compatible solutions were defined as those with added calcium and phosphate with no visual evidence of precipitation and mean particle size <1000 nm. In solutions containing 2.5–3% amino acids and 10 mmol/L of calcium chloride the maximum amount of potassium phosphate that was compatible was 7.5 mmol/L. Conclusion Maximum amounts of phosphate that could be added to parenteral nutrition solutions containing Trophamine and calcium chloride were about 7.5–10 mmol/L less for a given concentration of calcium based upon laser methodology compared to visual techniques to determine compatibility. There were minor differences in compatibility when adding calcium chloride and potassium phosphate to Premasol versus Trophamine. PMID:25192060

Huston, Robert K.; Christensen, J. Mark; Karnpracha, Chanida; Rosa, Jill E.; Clark, Sara M.; Migaki, Evelyn A.; Wu, YingXing

2014-01-01

37

Comparative proteomic and metabolomic analyses reveal mechanisms of improved cold stress tolerance in bermudagrass (Cynodon dactylon (L.) Pers.) by exogenous calcium.  

PubMed

As an important second messenger, calcium is involved in plant cold stress response, including chilling (<20?°C) and freezing (<0?°C). In this study, exogenous application of calcium chloride (CaCl2 ) improved both chilling and freezing stress tolerances, while ethylene glycol-bis-(?-aminoethyl) ether-N,N,N,N-tetraacetic acid (EGTA) reversed CaCl2 effects in bermudagrass (Cynodon dactylon (L.) Pers.). Physiological analyses showed that CaCl2 treatment alleviated the reactive oxygen species (ROS) burst and cell damage triggered by chilling stress, via activating antioxidant enzymes, non-enzymatic glutathione antioxidant pool, while EGTA treatment had the opposite effects. Additionally, comparative proteomic analysis identified 51 differentially expressed proteins that were enriched in redox, tricarboxylicacid cycle, glycolysis, photosynthesis, oxidative pentose phosphate pathway, and amino acid metabolisms. Consistently, 42 metabolites including amino acids, organic acids, sugars, and sugar alcohols were regulated by CaCl2 treatment under control and cold stress conditions, further confirming the common modulation of CaCl2 treatment in carbon metabolites and amino acid metabolism. Taken together, this study reported first evidence of the essential and protective roles of endogenous and exogenous calcium in bermudagrass response to cold stress, partially via activation of the antioxidants and modulation of several differentially expressed proteins and metabolic homeostasis in the process of cold acclimation. PMID:24428341

Shi, Haitao; Ye, Tiantian; Zhong, Bao; Liu, Xun; Chan, Zhulong

2014-11-01

38

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

Microsoft Academic Search

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

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

2006-01-01

39

Structure of wood extract colloids and effect of CaCl2 on the molecular mobility  

E-print Network

-layered model for the colloid structure for both pinus and spruce wood extracts has been proposed (Qin et alStructure of wood extract colloids and effect of CaCl2 on the molecular mobility Roland Lee, Karen J. Turro KEYWORDS: Wood resin, Pitch, Colloid structure, Electron paramagnetic resonance

Turro, Nicholas J.

40

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

NASA Astrophysics Data System (ADS)

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

Offenhartz, P. O.

1982-03-01

41

Effect of 1-methylcyclopropene and calcium chloride treatments on quality maintenance of 'Lingwu Long' Jujube fruit.  

PubMed

'Lingwu Long' jujube (Zizyphus jujuba cv. Mill) fruits were harvested at mature-green stages and then treated with 1.0 ?L L(-1) 1-methylcyclopropene (1-MCP), 1.0% CaCl2 or their combination. All treatments were stored at room temperature (22?±?1 °C) and 80-90% relative humidity (RH) up for 15 days. Results indicated that 1.0 ?L L(-1) 1-MCP, 1.0% CaCl2 or their combination were effective in terms of senescence inhibition, and the storage life was extended by 6, 4 and 9 days, respectively. 1-MCP and CaCl2 treatment had a synergic effect on the inhibition of ethylene production and microbial population of 'Lingwu Long' jujube fruit. The combination of 1-MCP and CaCl2 significantly reduced polygalacturonase (PG) and polyphenoloxidase (PPO) activities. It also maintained higher concentrations of titratable acid and ascorbic acid. PMID:24741163

Li, Li; Ban, Zhaojun; Li, Xihong; Xue, Ting

2014-04-01

42

Adsorption of Mercuric Chloride Vapours from Incinerator Flue Gases on Calcium Hydroxide Particles  

Microsoft Academic Search

The adsorption of mercuric chloride vapours on a fixed bed of calcium hydroxide fine particles has been experimentally studied. The study has been conducted at laboratory scale using simulated flue gases, constituted of mercuric chloride vapours in nitrogen, which have been in contact with a Ca(OH)2 fixed bed. The effect of the bed temperature, the inlet HgCl2 concentration, and the

A. LANCIA; D. MUSMARRA; G. Volpicelli; Francesco Pepe

1993-01-01

43

Exogenously applied calcium alleviates cadmium toxicity in Matricaria chamomilla L. plants.  

PubMed

Cadmium (Cd) toxicity in plants leads to serious disturbances of physiological processes, such as inhibition of chlorophyll synthesis, oxidative injury to the plant cells and water and nutrient uptake. Response of Matricaria chamomilla L. to calcium chloride (CaCl(2)) enrichment in growth medium for reducing Cd toxicity were studied in this study. Hydroponically cultured seedlings were treated with 0, 0.1, 1, and 5 mM CaCl(2), under 0, 120, and 180 ?M CdCl(2) conditions, respectively. The study included measurements pertaining to physiological attributes such as growth parameters, Cd concentration and translocation, oxidative stress, and accumulation of phenolics. Addition of CaCl(2) to growth media decreased the Cd concentration, activity of antioxidant enzymes, and reactive oxygen species accumulation in the plants treated with different CdCl(2), but increased the growth parameters. Malondialdehyde and total phenolics in shoots and roots were not much affected when plants were treated only with different CaCl(2) levels, but it showed a rapid increase when the plants were exposed to 120 and 180 CdCl(2) levels. CaCl(2) amendment also ameliorated the CdCl(2)-induced stress by reducing oxidative injury. The beneficial effects of CaCl(2) in ameliorating CdCl(2) toxicity can be attributed to the Ca-induced reduction of Cd concentration, by reducing the cell-surface negativity and competing for Cd(2+) ion influx, activity enhancement of antioxidant enzymes, and biomass accumulation. PMID:22968674

Farzadfar, Soudeh; Zarinkamar, Fatemeh; Modarres-Sanavy, Seyed Ali Mohammad; Hojati, Mostafa

2013-03-01

44

CaCl2 -type high-pressure phase of magnesium hydride predicted by ab initio phonon calculations  

NASA Astrophysics Data System (ADS)

A pressure-induced transition in magnesium hydride (MgH2) from the tetragonal rutile phase to an orthorhombic CaCl2 phase is predicted by ab initio phonon calculations. The phase transition is identified as a second-order nature, driven by the softening of the Raman active B1g phonon mode, weakly coupling with the elastic shear modulus Cs . The newly predicted CaCl2 phase is dynamically stable, and the calculated equation of states shows good agreement with the available experimental data. Analysis of the calculated results of Gibbs free energies and Raman active phonons for both rutile and CaCl2 phase, and the spontaneous strains for CaCl2 phase, further supports the existence of this new phase.

Zhang, Lijun; Wang, Yanchao; Cui, Tian; Li, Yan; Li, Yinwei; He, Zhi; Ma, Yanming; Zou, Guangtian

2007-04-01

45

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

PubMed

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

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

2014-01-01

46

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

PubMed Central

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

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

2014-01-01

47

A study of the oral toxicity of calcium chloride in dairy cows.  

PubMed

The effects of oral administration of calcium chloride solutions to dairy cows were studied. When a 0.3 per cent solution was given ad libitum, and as the sole source of water for a period of 75 days, we observed no significant changes in feed consumption, body weight or milk production. The average daily water intake was increased by approximately 20 per cent, and signs of slight gastro-intestinal irritation were seen. No major changes in blood hemoglobin levels, hematocrits, total and differential white cell counts or thrombocyte numbers could be attributed to the treatment. We observed no significant effect on the serum calcium, chloride, magnesium, potassium, or sodium content. The level of inorganic phosphate in the serum rose to higher, but still normal values. During the entire experiment the urine pH was abnormally acid for dairy cows. Electrocardiograms were taken after 45 days of calcium chloride administration, and they appeared normal. When 0.1 and 0.2 per cent solutions were given as the sole source of water for a period of 81 days, the cows remained in good condition, and we observed no changes in appetite, body weight or milk production. In general, dairy cows will refuse to drink calcium chloride solutions when the concentration exceeds 0.5 per cent, even when they have been deprived of water for 18-24 hours. On the other hand, since the administration of lower concentrations for periods of 75 and 81 days did not cause any clinical sign of disease, it seems that on farms where more than one source of water are usually available, poisoning of dairy cattle by calcium chloride in solution is quite unlikely. PMID:4223697

Mathieu, L G; Pelletier, R P

1966-02-01

48

Electrochemical Behavior of Titanium(II) Ion in a Purified Calcium Chloride Melt  

NASA Astrophysics Data System (ADS)

Cyclic voltammetry, chronopotentiometry, and square wave voltammetry were used to investigate electrochemical behavior of Ti(II) ion in a purified CaCl2 melt at a temperature of 1173 K (900 °C). The result indicated that the cathodic reduction of Ti(II) ion in the melt was a one-step quasi-reversible process controlled by the diffusion. The diffusion coefficient was determined in a CaCl2-TiCl(0.5 mol/dm3) at 1173 K (900 °C). The work also demonstrated the feasibility of producing metallic titanium in the as-prepared CaCl2-TiCl2 melts through galvanostatic electrolysis.

Kang, Min Ho; Song, Jianxun; Zhu, Hongmin; Jiao, Shuqiang

2014-09-01

49

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

PubMed Central

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

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

2014-01-01

50

Critical behavior of thermal phase transitions of iota-carrageenan in CaCl 2 solution  

NASA Astrophysics Data System (ADS)

In situ photon transmission method was applied to study thermal phase transitions of ?-carrageenan in CaCl 2 solution. Coil-to-helix (c-h) and helix-to-dimer (h-d) transitions were detected upon cooling. An extra dimer-to-dimer (d-d) transition was observed as well during cooling at low-temperature region. Upon heating only dimer-to-helix (d-h) and helix-to-coil (h-c) transitions were detected. Photon transmission intensity, Itr was monitored against temperature to determine several phase transitions and transition temperatures. It was observed that the c-h transition in ?-carrageenan-CaCl 2 system performs a crossover between 3D percolation to classical theory. Upon heating, the specific heat exponent over the d-h transition was extracted from the transmitted intensity data and was found to be 0.045.

Özbek, Haluk; Pekcan, Önder

2006-07-01

51

Formation condition of monohydrocalcite from CaCl2-MgCl2-Na2CO3 solutions  

NASA Astrophysics Data System (ADS)

Monohydrocalcite (MHC: CaCO3·H2O) is a rare mineral in geological settings. Its rare occurrence indicates that MHC forms in unique environmental conditions in nature. Both laboratory studies and natural observations have indicated that the formation of MHC requires magnesium in the solution in spite of the incompatibility of magnesium into the MHC structure. In this study, systematic syntheses from CaCl2-MgCl2-Na2CO3 solutions were conducted to elucidate MHC formation conditions and to clarify the role of magnesium in MHC formation. For this study, MHC was formed from mixing solutions of which the ratio of the total carbonate to calcium was higher than 1 in the presence of a certain amount of magnesium. The pH of the reacted solutions after the MHC formation was 9.8-11.0. The solid-phase magnesium contents in the formed precipitates were widely varied. MHC exhibits low crystallinity and small particle size when the ratio of magnesium to calcium in the solid was higher than 0.4. After MHC formation, ion activity products of the reacted solutions with respect to MgCO3·xH2O stoichiometry took almost constant values. The ion activity products were significantly higher than the solubility product of anhydrous MgCO3, but they were close to the solubility of nesquehonite, which indicates that MHC formation of requires paragenesis of the hydrous magnesium carbonate. To produce the hydrous magnesium carbonate simultaneously with MHC, the initial solution must contain magnesium and more CO32- than Ca2+, which is consistent with the formation conditions of MHC from the initial solution compositions. Magnesium ion possesses a high hydration energy. The hydrous magnesium carbonates surrounding MHC probably play a protective role for MHC in preventing its dehydration to anhydrous calcium carbonate. The solution chemistries of saline lakes of which the MHC formation was observed in nature are also at equilibrium or are oversaturated with respect to hydrous magnesium carbonates and MHC. Rare occurrences of MHC in nature are explainable by the paragenesis requirements of hydrous magnesium carbonates and by the metastability of MHC.

Nishiyama, Risa; Munemoto, Takashi; Fukushi, Keisuke

2013-01-01

52

A calcium- and voltage-dependent chloride current in developing chick skeletal muscle.  

PubMed Central

1. Depolarization of embryonic chick myotubes from negative potentials elicits a rapid spike followed by a long-duration after-potential. The ionic basis of the long-duration after-potential was examined by making intracellular recordings from cultured myotubes, and by making whole-cell patch-clamp recordings from myoblasts and myoballs. 2. The peak potential of the long-duration after-potential varied with the chloride gradient, suggesting that a conductance increase to chloride is involved in generating the after-potential. However, a calcium current was also implicated, since lowering the extracellular calcium or replacing extracellular calcium with cobalt abolished the after-potential. 3. When extracellular calcium was replaced with strontium or barium, short-duration spikes similar to calcium spikes were observed, but only strontium was able to support activation of long-duration after-potentials. Intracellular injection of calcium or strontium into myotubes bathed in calcium-free extracellular solutions restored the ability of depolarization to evoke an after-potential. Intracellular injection of magnesium, barium, nickel or cobalt did not restore this ability. These experiments strongly suggested that the long-duration after-potential was due to a calcium- and voltage-activated chloride current. 4. Whole-cell voltage-clamp recordings from myoballs and myoblasts showed that a large chloride conductance could be activated by depolarization when the internal free calcium concentration was buffered at levels greater than 10(-7) M. At 2.5 x 10(-7) M-calcium, the voltage dependence of activation was steepest in the range of -30 to -20 mV and the activation kinetics varied with the membrane potential. The time to half-maximal activation ranged from 0.1 s at positive potentials to greater than 1 s at more negative potentials. The time constant for deactivation was approximately 1 s at -50 mV. No inactivation was observed. 5. The selectivity of the chloride current was measured by substituting other anions for chloride. The following permeability series was found: I- greater than NO3- greater than Br- greater than Cl- greater than acetate greater than F- greater than SO4- = glucuronate. Thus anion permeability decreased as the hydration radius increased. 6. Measurements of the resting potential of developing myoblasts and myotubes under 'physiological' conditions (37 degrees C, bicarbonate buffer) suggest that the after-potential acts to depolarize these cells 10-20 mV above their resting potential (approximately -60 mV) for several seconds. 7. We discuss the possibility that the long-duration after-potential may be involved in triggering myoblast fusion and in the generation of bursts of spontaneous contractions in developing myotubes. PMID:2482883

Hume, R I; Thomas, S A

1989-01-01

53

Firmness and cell wall characteristics of pasteurized jalapeno pepper rings affected by acetic acid, calcium chloride and preheating  

E-print Network

pasteurization and storage, especially when high acid brines are used. Development of treatments to retard softening may result in a higher quality product. This study was undertaken to investigate the effects of calcium chloride (CaCI2), acetic acid...

Burma, Prashanthi V

2012-06-07

54

Influence of lactose on the diffusion of calcium ions at physiological temperature.  

PubMed

Mutual diffusion coefficients for calcium chloride (0.100 mol dm(-3)) in aqueous solutions containing lactose at various concentrations (from 0.005 to 0.200 mol dm(-3)) have been measured at 37°C (physiological temperature), by using a conductimetric cell coupled to an automatic system to follow the diffusion. This cell uses an open-ended capillary method based on the measurement of the electrical resistance of a solution placed inside the capillaries at recorded times. The analysis of the CaCl2 diffusion coefficient values obtained suggests the presence of some CaCl2/lactose aggregates in the media, which are influenced by the temperature. PMID:24912727

Verissimo, Luis M P; Ribeiro, Vânia C M; Ribeiro, Ana C F; Melia Rodrigo, M; Esteso, Miguel A

2014-11-15

55

A study of the effects of nickel chloride and calcium chloride on hydration of Portland cement  

SciTech Connect

Portland cement samples containing amounts of CaCl[sub 2] and NiCl[sub 2] ranging from approximately 1% to 20% by weight have been examined by [sup 29]Si and [sup 27]Al solid-state MAS NMR as a function of time, and some of the mature pastes have been characterized by X-ray diffraction. Changes in physical properties that had been previously observed as a function of amounts of salt added are clearly traceable to differences in the silicate matrices. Low concentrations of both salts promote Q[sup 1] formation, but high concentrations result in formation of much more Q[sup 2] at the expense of Q[sup 1]. Both salts accelerate both aluminate and silicate hydration, and the effects appear to be almost entirely due to chloride. Minor variations in hydration rates at high Ni concentrations may be the result of nickel salt precipitation.

Akhter, H.; Cartledge, F.K.; Roy, A.; Tittlebaum, M.E. (Louisiana State Univ., Baton Rouge (United States). Department of Chemistry and Institute for Recyclable Materials)

1993-07-01

56

Selective water sorbents for multiple applications, 1. CaCl 2 confined in mesopores of silica gel: Sorption properties  

Microsoft Academic Search

This paper presents sorption properties of a selective water sorbent based on mesoporous KSKG silica gel as a host matrix and calcium chloride as a hygroscopic salt. Sorption isobars, isochores and isotherms at T=20–150°C and vapor partial pressures of 8–133 mbar clearly showed two types of water sorption: 1) the formation of solid crystal hydrates at low amounts N of

Yu. I. Aristov; M. M. Tokarev; G. Cacciola; G. Restuccia

1996-01-01

57

The effect of sodium chloride on the dissolution of calcium silicate hydrate gels  

SciTech Connect

The use of cement based materials will be widespread in the long-term management of radioactive materials in the United Kingdom. One of the applications could be the Nirex reference vault backfill (NRVB) as an engineered barrier within a deep geological repository. NRVB confers alkaline conditions, which would provide a robust chemical barrier through the control of the solubility of some key radionuclides, enhanced sorption and minimised corrosion of steel containers. An understanding of the dissolution of C-S-H gels in cement under the appropriate conditions (e.g., saline groundwaters) is necessary to demonstrate the expected evolution of the chemistry over time and to provide sufficient cement to buffer the porewater conditions for the required time. A programme of experimental work has been undertaken to investigate C-S-H gel dissolution behaviour in sodium chloride solutions and the effect of calcium/silicon ratio (C/S), temperature and cation type on this behaviour. Reductions in calcium concentration and pH values were observed with samples equilibrated at 45 deg. C compared to those prepared at 25 deg. C. The effect of salt cation type on salt-concentration dependence of the dissolution of C-S-H gels was investigated by the addition of lithium or potassium chloride in place of sodium chloride for gels with a C/S of 1.0 and 1.8. With a C/S of 1.0, similar increases in dissolved calcium concentration with increasing ionic strength were recorded for the different salts. However, at a C/S of 1.8, anomalously high calcium concentrations were observed in the presence of lithium.

Hill, J. [UK Nirex Limited, Curie Avenue, Harwell, Didcot Oxfordshire, OX11 0RH (United Kingdom)]. E-mail: joanne.hill@nirex.co.uk; Harris, A.W. [UK Nirex Limited, Curie Avenue, Harwell, Didcot Oxfordshire, OX11 0RH (United Kingdom); Manning, M. [Formerly AEA Technology, Building 220, Harwell, Didcot Oxfordshire, OX11 0RA (United Kingdom); Chambers, A. [Serco Assurance, Building 150, Harwell International Business Centre, Didcot, Oxfordshire, OX11 0RA (United Kingdom); Swanton, S.W. [Serco Assurance, Building 150, Harwell International Business Centre, Didcot, Oxfordshire, OX11 0RA (United Kingdom)

2006-07-01

58

Osmotic dehydration of apple slices with CaCl2 and sucrose limits decay caused by Penicillium expansum, Colletotrichum acutatum, and Botrytis cinerea and does not promote Listeria monocytogenes or total aerobic population growth.  

PubMed

The interaction of Penicillium expansum Link, Colletotrichum acutatum, and Botrytis cinerea Pers.:Fr. with Listeria monocytogenes on osmotically dehydrated apple slices was evaluated. In mineral analyses of the slices, the calcium content of the peel and flesh tissues increased by 4- and 11-fold, respectively, when processed in 2% CaCl2. These slices also exhibited less decay by P. expansum, C. acutatum, and B. cinerea. Inoculation of slices with P. expansum resulted in a decrease in the pH of the flesh tissue at the infection site, while the pHs of slices infected with C. acutatum and B. cinerea increased and remained stable, respectively. Total mold population increased in wounds inoculated with P. expansum or C. acutatum. The presence of L. monocytogenes in the wounds did not significantly affect mold growth. The association of P. expansum and L. monocytogenes on apple slices resulted in a decrease in the bacterial population, whereas L. monocytogenes survived when slices were inoculated with C. acutatum. When associated with B. cinerea, there was a fourfold decrease in the L. monocytogenes population when slices were treated with 2% CaCl2. The total aerobic population was not significantly affected by the type of microorganism added to the wounds or by the osmotic treatment. These data show that osmotic dehydration with 2% CaCl2 combined with 20% sucrose limits decay of apple slices and does not promote bacterial or total aerobic population growth. PMID:11808790

Chardonnet, Catherine O; Sams, Carl E; Conway, William S; Draughon, Frances A; Mount, John R

2002-01-01

59

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

PubMed

In this work, we developed a new method to prepare porous PA6 with different morphologic feature and crystalline forms via the decomplexation of PA6/CaCl2 composite. The structures and morphology of thus obtained materials were characterized by vibrational spectroscopy (FT-IR and Raman) and scanning electron microscope (SEM) method. When amorphous PA6/CaCl2 composite films were treated in water at room temperature, PA6 re-arranges into ? form. However, decomplexation of the PA6/CaCl2 composite in boiling water produces PA6 in ? crystalline form. If the PA6/CaCl2 composite is soaked in methanol, part of PA6 is dissolved or swollen in methanol/metal salt solutions. As a result, a dissolve/precipitation process occurred during the decomplexation process, which led to the formation of PA6 in ? crystalline form. Further investigation demonstrates that the morphologies of the porous PA6 could be adjusted by using different solvents and/or different decomplexation conditions. PMID:23892342

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

2013-11-01

60

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

PubMed Central

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

Huang, Fen; Wong, Xiuming

2012-01-01

61

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

PubMed Central

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

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

2013-01-01

62

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

PubMed

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

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

2013-01-01

63

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

PubMed Central

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

2011-01-01

64

Annexin A4 induces platinum resistance in a chloride-and calcium-dependent manner  

PubMed Central

Platinum resistance has long been a major issue in the treatment of various cancers. We previously reported that enhanced annexin A4 (ANXA4) expression, a Ca2+-regulated phospholipid-binding protein, induces chemoresistance to platinum-based drugs. In this study, we investigated the role of annexin repeats, a conserved structure of all the annexin family, responsible for platinum-resistance as well as the effect of knockdown of ANXA4. ANXA4 knockdown increased sensitivity to platinum-based drugs both in vitro and in vivo. To identify the domain responsible for chemoresistance, ANXA4 deletion mutants were constructed by deleting annexin repeats one by one from the C terminus. Platinum resistance was induced both in vitro and in vivo in cells expressing either full-length ANXA4 or the deletion mutants, containing at least one intact annexin repeat. However, cells expressing the mutant without any calcium-binding sites in the annexin repeated sequence, which is essential for ANXA4 translocation from the cytosol to plasma membrane, failed to acquire platinum resistance. After cisplatin treatment, the intracellular chloride ion concentration, whose channel is partly regulated by ANXA4, significantly increased in the platinum-resistant cells. These findings indicate that the calcium-binding site in the annexin repeat induces chemoresistance to the platinum-based drug by elevating the intracellular chloride concentration. PMID:25277200

Morimoto, Akiko; Serada, Satoshi; Enomoto, Takayuki; Kim, Ayako; Matsuzaki, Shinya; Takahashi, Tsuyoshi; Ueda, Yutaka; Yoshino, Kiyoshi; Fujita, Masami; Fujimoto, Minoru; Kimura, Tadashi; Naka, Tetsuji

2014-01-01

65

Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intratesticular Injection of Calcium Chloride  

Microsoft Academic Search

Background  Calcium chloride solution is an established injectable sterilant in dogs and other mammals. With cat populations a continuing\\u000a problem, we sought to explore its first use in cats. Six cats per group were injected with 5%, 10% or 20% calcium chloride\\u000a dihydrate in saline solution with lignocaine hydrochloride, a local anaesthetic.\\u000a \\u000a \\u000a \\u000a \\u000a Results  At the 60th day post-injection, cat testes were collected

Kuladip Jana; Prabhat K Samanta

2011-01-01

66

Performance optimization of coagulation/flocculation in the treatment of wastewater from a polyvinyl chloride plant.  

PubMed

This paper presents results of an experimental study of coagulation/flocculation process of wastewater generated from a polyvinyl chloride (PVC) plant. The wastewater contains fine chlorine-based solid materials (i.e. latex). Experiments were carried out using a model wastewater which is chemically identical to the actual plant but is more consistent. Inorganic ions (Al2(SO4)3, FeCl3 and CaCl2) and a water soluble commercial polyelectrolyte (PE) were added to the wastewater sample. Coagulation efficiency was determined by measuring both the turbidity of the supernatants and the relative settlement of the flocs in the jar test. It was found that aluminum and ferric ions were more efficient than calcium ions as coagulants. The addition of polyelectrolyte was found to improve substantially the coagulation/flocculation process. It was found that the (Al2(SO4)3) combined with the polyelectrolyte at certain pH and agitation speed gave the best results compared to calcium chloride or ferric chloride when combined with the same concentration of polyelectrolyte. Only 0.0375g of a solution of (0.5% Al2(SO4)3) was required to coagulate the model wastewater. Ferric chloride (2.5% FeCl3) combined with the polyelectrolyte, on the other hand, required 0.1g while the optimum turbidity is almost the same. As for calcium chloride (2.5% CaCl2) it was found to be the least effective. The coagulation/flocculation process was found to be dependent on both pH and the agitation speed. PMID:18471966

Almubaddal, F; Alrumaihi, K; Ajbar, A

2009-01-15

67

The effect of calcium on gill potentials and on sodium and chloride fluxes in the goldfish, Carassius auratus  

Microsoft Academic Search

Measurements of electric potential and of sodium and chloride effluxes were carried out on a freshwater fish, the goldfishCarassius auratus. The potential was affected by a number of inorganic ion species but that with the most significant influence on transepithelial potential was calcium. The potential was about 10 mV negative in the absence of calcium and about 10 mV positive

F. B. Eddy

1975-01-01

68

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

PubMed

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

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

2014-10-01

69

Relationship between ph measured in water and calcium chloride for soils of Southwestern Australia  

Microsoft Academic Search

Soil pH in southwestern Australia (WA) is usually measured either in water (pHw) or 0.01M CaCl2 (pHCa). There are no published relationships to convert one pH to the other. This has been done in this paper for 236 WA soils: pHCa=0.918 pHw?0.3556, r=0.9401. It is, therefore, concluded that, for the majority of soils within WA, it is likely that the

R. F. Brennan; M. D. A. Bolland

1998-01-01

70

Aluminum diffusion in Oxisols as influenced by soil water matric potential, ph, lime, gypsum, potassium chloride, and calcium phosphate  

Microsoft Academic Search

Plant root exposure to soil aluminum (Al) depends on the soil solution Al concentration and transport to the root by diffusion. Changes in Al diffusive flux for two Oxisols was measured under laboratory conditions as a function of pH, water matric potential, and applications of gypsum, potassium chloride, and calcium phosphate. Double?faced cation exchange resin sheets served as sinks for

F. H. T. Oliveira; R. F. Novais; T. J. Smyth; J. C. L. Neves

2000-01-01

71

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

PubMed

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

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

2014-03-01

72

The release behavior of brilliant blue from calcium–alginate gel beads coated by chitosan: the preparation method effect  

Microsoft Academic Search

The aim of this study is to reveal how the release behavior of a model drug (brilliant blue, BB) from chitosan coating calcium–alginate gel beads (CCAGB) was influenced by the preparation methods. The CCAGB were prepared by dropping alginate solution into CaCl2\\/chitosan solution (method 1(a)), or into chitosan solution then gelled by CaCl2 (method 1(b)), or into CaCl2 solution then

X. Z Shu; K. J Zhu

2002-01-01

73

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

74

Novel 5-substituted benzyloxy-2-arylbenzofuran-3-carboxylic acids as calcium activated chloride channel inhibitors.  

PubMed

Transmembrane protein 16A (TMEM16A) channels are recently discovered membrane proteins that functions as a calcium activated chloride channel (CaCC). CaCCs are major regulators of various physiological processes, such as sensory transduction, epithelial secretion, smooth muscle contraction and oocyte fertilization. Thirty novel 5-substituted benzyloxy-2-arylbenzofuran-3-carboxylic acids (B01-B30) were synthesized and evaluated for their TMEM16A inhibitory activity by using short circuit current measurements in Fischer rat thyroid (FRT) cells expressing human TMEM16A. IC(50) values were calculated using YFP fluorescence plate reader assay. Final compounds, having free carboxylic group displayed significant inhibition. Eight of the novel compounds B02, B13, B21, B23, B25, B27, B28, B29 exhibit excellent CaCCs inhibition with IC(50) value <6 ?M, with compound B25 exhibiting the lowest IC(50) value of 2.8 ± 1.3 ?M. None of the tested ester analogs of final benzofuran derivatives displayed TMEM16A/CaCCs inhibition. PMID:22739085

Kumar, Satish; Namkung, Wan; Verkman, A S; Sharma, Pawan K

2012-07-15

75

Long-term uncoupling of chloride secretion from intracellular calcium levels by lns(3,4,5,6)P4  

Microsoft Academic Search

OSMOREGULATION, inhibitory neurotransmission and pH balance depend on chloride ion (Cl-) flux. In intestinal epithelial cells, apical Cl- channels control salt and fluid secretion and are, in turn, regulated by agonists acting through cyclic nucleotides and internal calcium ion concentration ([Ca2 +]i)1-3. Recently, we found that muscarinic pretreatment prevents [Ca2 +]i increases from eliciting Cl- secretion in T84 colonic epithelial

Mana Vajanaphanich; Carsten Schultz; Marco T. Rudolf; Matthew Wasserman; Péter Enyedi; Andrew Craxton; Stephen B. Shears; Roger Y. Tsien; Kim E. Barrett; Alexis Traynor-Kaplan

1994-01-01

76

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

...MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LEASING OF SOLID MINERALS OTHER THAN COAL AND OIL SHALE Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive...

2014-10-01

77

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

Code of Federal Regulations, 2012 CFR

...MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LEASING OF SOLID MINERALS OTHER THAN COAL AND OIL SHALE Lease Terms and Conditions § 3511.11 If I am mining calcium chloride, may I obtain a noncompetitive...

2012-10-01

78

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

PubMed Central

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

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

2011-01-01

79

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

SciTech Connect

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

Vijay Sethi; M.P. Sharma

2009-02-28

80

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

PubMed

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

Lau, L-C; Adaikan, P G

2014-01-01

81

Calorimetric investigation on zeolites, AlPO 4's and CaCl 2 impregnated attapulgite for thermochemical storage of heat  

Microsoft Academic Search

The sorption properties of water in potential thermochemical storage materials such as low silica X zeolites, microporous aluminophosphates, SAPO-34 and CaCl2 accommodated in the pores of attapulgite were investigated by thermogravimetry, differential scanning calorimetry, sorption isotherms and microcalorimetry.Because of decreasing differential molar heats of sorption from LiLSX (100–70kJ\\/mol) to SAPO-34 (90–65kJ\\/mol) and to supported CaCl2 (70–50kJ\\/mol) the isotherms are shifted

J. Jänchen; D. Ackermann; E. Weiler; H. Stach; W. Brösicke

2005-01-01

82

Phase transition and optical properties of CaCl2 under high pressure by ab initio pseudopotential plane-wave calculations  

NASA Astrophysics Data System (ADS)

We present a detailed investigation of CaCl2 under high pressure in CaCl2 (Pnnm,Z = 2) and ?-PbO2 (Pbcn, Z = 4) phases, respectively. Theoretical calculations are performed by using the ab initio pseudopotential plane-wave method based on the density functional method. We estimate the transition pressure between the two phases by the crossing point of their enthalpies, which are equivalent to the Gibbs free energy at zero temperature, after optimizing the structures under high pressure. Our results show that the transition happens at about 2.9 GPa, which is in agreement with the experimental data. We calculate the structural parameters, charge transfers, bond structures, density of states and optical properties. The calculated results show that there are no charge transfers in CaCl2 structure under high pressure. It is found that the transitions from the Cl 3p to Ca 4s and Cl 3s to Ca 3p orbitals contribute mainly to the dielectric function. The optical properties of CaCl2 (Pnnm, Z = 2) do not vary much under pressure. However, some of the dispersion curves of optical constants in the ?-PbO2 (Pbcn, Z = 4) phase are changed significantly under pressure.

Liu, Y. H.; Ma, Y. M.; He, Z.; Cui, T.; Liu, B. B.; Zou, G. T.

2007-10-01

83

Quasielastic neutron scattering study of dynamics of CaCl2 aqueous solution confined in Vycor glass.  

PubMed

Quasielastic neutron scattering was used to probe the diffusion of water molecules in 2.3 molal CaCl(2) solution confined in 100% hydrated Vycor glass in the temperature range of 220 to 260 K. We observed a gradual transition from the restricted diffusion regime at lower temperatures to unrestricted diffusion regime at higher temperatures. The diffusion parameters were compared with the data on pure water confined in Vycor available in the literature. We found that the effect of dissolved ions onto the diffusion dynamics of the water molecules in the solution was amplified by confinement by at least an order of magnitude compared to bulk form, even though the dissolved ions were found to have little effect on the spatial characteristics of the restricted diffusion process of water molecules. At 260 K, the local diffusion coefficient of water molecules in the H(2)O-CaCl(2) confined in Vycor was only 6% of the value reported for pure water confined in Vycor. PMID:17066181

Mamontov, E; Cole, D R

2006-11-14

84

Calcium-Activated Chloride Channels (CaCCs) Regulate Action Potential and Synaptic Response in Hippocampal Neurons  

PubMed Central

SUMMARY Central neurons respond to synaptic inputs from other neurons by generating synaptic potentials. Once the summated synaptic potentials reach threshold for action potential firing, the signal propagates leading to transmitter release at the synapse. The calcium influx accompanying such signaling opens calcium-activated ion channels for feedback regulation. Here we report a novel mechanism for modulating hippocampal neuronal signaling that involves calcium-activated chloride channels (CaCCs). We present the first evidence that CaCCs reside in hippocampal neurons and are in close proximity of calcium channels and NMDA receptors to shorten action potential duration, dampen excitatory synaptic potentials, impede temporal summation, and raise the threshold for action potential generation by synaptic potential. Having recently identified TMEM16A and TMEM16B as CaCCs, we further show that TMEM16B but not TMEM16A is important for hippocampal CaCC, laying the groundwork for deciphering the dynamic CaCC modulation of neuronal signaling in neurons important for learning and memory. PMID:22500639

Huang, Wendy C.; Xiao, Shaohua; Huang, Fen; Harfe, Brian D.; Jan, Yuh Nung; Jan, Lily Yeh

2012-01-01

85

Host-pathogen-biocontrol agent interaction as affected by sequential application of Na2CO3 and CaCl2.  

PubMed

Among the alternatives to synthetic postharvest fungicides encouraging results have been reported with biocontrol agents, and on Citrus fruits, their efficacy was improved when co-applied with GRAS compounds or with physical means. Still, the reason for this increased efficacy has not been explained and therefore a study was performed using orange fruit (Citrus sinensis Osbec. cv 'Washington navel') as host, P. digitatum as the pathogen, a yeast (Pichia guiliermondii, isolate 5A) as the biocontrol agent, white 2% Na2CO3 (SC) and 1% CaCl2 were employed as GRAS compounds. When treatments were combined salts were applied sequentially, and SC preceded CaCl2 followed by the yeast. As a result of large scale trait with inoculated and un-inoculated fruit a clear beneficial interaction occurred when treatments were combined. SC exerted a direct fungistatic activity and an indirect one by inducing scoparone in host tissue. Also the isolate A5 induced the phytoalexin accumulation and when combined with SC a greater accumulation occurred within the first 7 days post-treatment. The application of CaCl2 alone had no effect on pathogenesis, while when combined with SC or with the yeast, decay was towered. The yeast growth on an amended medium was negatively affected by the addition of SC; while in vivo this effect was missing. The antagonist growth in vivo was enhanced when applied together with 1% CaCl2 also when applied with SC. The results reported improve our knowledge on the complex interactions among host, pathogen and the antagonist as affected by SC and CaCl2. PMID:20222553

Molinu, G M; Arras, G; Dore, A; Venditti, T; Petretto, A; D'Hallewin, G

2009-01-01

86

Calcium  

MedlinePLUS

... when taken with food. Some over-the-counter antacid products, such as Tums® and Rolaids®, contain calcium ... calcium excretion and thereby lower blood calcium levels. Antacids containing aluminum or magnesium increase calcium loss in ...

87

Calcium  

MedlinePLUS

... lead levels. Calcium carbonate is used as an antacid for “heartburn.” Calcium carbonate and calcium acetate are ... when given intravenously (by IV). Use as an antacid as calcium carbonate. Reducing phosphate levels in people ...

88

In vitro fertilization in inbred BALB/c mice I: isotonic osmolarity and increased calcium-enhanced sperm penetration through the zona pellucida and male pronuclear formation.  

PubMed

To optimize IVF conditions for BALB/c mice, which are known to have poor in vitro fertilizability, the requirements for sperm-ova interaction were studied by use of modified simplex optimization medium (mKSOM) as a basic medium. Modified human tubal fluid (mHTF) was used for sperm preincubation and acted as a positive control. When the two media were compared, neither capacitation nor fertilization was supported in mKSOM. Increasing the calcium concentration in mKSOM to 5 mM or more during sperm: ova coincubation improved zona penetration but not male pronuclear (MPN) formation to the same level as those cells incubated in mHTF. When medium osmolarity was varied from 230-305 mOsmol by NaCl at 5 mM CaCl2, MPN formation improved at 280 mOsmol or higher osmolarity to the same level as that found when using mHTF. When NaCl equivalent to 25-75 mOsmol was substituted with trehalose, no significant reduction in fertilization was observed. Substitution of NaCl equivalent to 75 mOsmol with other osmotic reagents (sucrose, choline chloride and sorbitol) resulted in similar levels of fertilization as found with mHTF, except for sorbitol, which reduced fertilization significantly caused by its detrimental effect on sperm viability. At isotonic osmolarity (305 mOsmol), maximum fertilization was observed at 5 mM CaCl2; lower or higher concentrations of CaCl2 resulted in reduced fertilization. Calcium and osmolarity, therefore, are important for sperm : ova interaction in BALB/c mice and the increases in calcium to 5 mM and osmolarity to 305 mOsmol are optimal for BALB/c sperm to penetrate through the zona and to form MPN. PMID:18578944

Kito, Seiji; Ohta, Yuki

2008-08-01

89

Effect of calcium source on structure and properties of sol-gel derived bioactive glasses.  

PubMed

The aim was to determine the most effective calcium precursor for synthesis of sol-gel hybrids and for improving homogeneity of sol-gel bioactive glasses. Sol-gel derived bioactive calcium silicate glasses are one of the most promising materials for bone regeneration. Inorganic/organic hybrid materials, which are synthesized by incorporating a polymer into the sol-gel process, have also recently been produced to improve toughness. Calcium nitrate is conventionally used as the calcium source, but it has several disadvantages. Calcium nitrate causes inhomogeneity by forming calcium-rich regions, and it requires high temperature treatment (>400 °C) for calcium to be incorporated into the silicate network. Nitrates are also toxic and need to be burnt off. Calcium nitrate therefore cannot be used in the synthesis of hybrids as the highest temperature used in the process is typically 40-60 °C. Therefore, a different precursor is needed that can incorporate calcium into the silica network and enhance the homogeneity of the glasses at low (room) temperature. In this work, calcium methoxyethoxide (CME) was used to synthesize sol-gel bioactive glasses with a range of final processing temperatures from 60 to 800 °C. Comparison is made between the use of CME and calcium chloride and calcium nitrate. Using advanced probe techniques, the temperature at which Ca is incorporated into the network was identified for 70S30C (70 mol % SiO(2), 30 mol % CaO) for each of the calcium precursors. When CaCl(2) was used, the Ca did not seem to enter the network at any of the temperatures used. In contrast, Ca from CME entered the silica network at room temperature, as confirmed by X-ray diffraction, (29)Si magic angle spinning nuclear magnetic resonance spectroscopy, and dissolution studies. CME should be used in preference to calcium salts for hybrid synthesis and may improve homogeneity of sol-gel glasses. PMID:23171477

Yu, Bobo; Turdean-Ionescu, Claudia A; Martin, Richard A; Newport, Robert J; Hanna, John V; Smith, Mark E; Jones, Julian R

2012-12-18

90

Crystal Screen Lite -Scoring Sheet 1. 15% MPD, 0.1 M Na Acetate pH 4.6, 0.02 M Calcium Chloride  

E-print Network

.2 M Magnesium Chloride 7. 0.7 M Sodium Acetate, 0.1 M Na Cacodylate pH 6.5 8. 15% iso-Propanol, 0.1 M.2 M Sodium Acetate 23. 15% PEG 400, 0.1 M Na Hepes pH 7.5, 0.2 M Magnesium Chloride 24. 10% iso-Propanol, 0.1 M Na Acetate pH 4.6, 0.2 M Calcium Chloride 25. 0.5 M Sodium Acetate, 0.1 M Imidazole pH 6.5 26

Hill, Chris

91

Crystal Screen HT -Scoring Sheet A1. 30% MPD, 0.1 M Na Acetate pH 4.6, 0.02 M Calcium Chloride  

E-print Network

.2 M Magnesium Chloride A7. 1.4 M Sodium Acetate, 0.1 M Na Cacodylate pH 6.5 A8. 30% iso-Propanol, 0H 8.5, 0.2 M Sodium Acetate B11. 30% PEG 400, 0.1 M Na Hepes pH 7.5, 0.2 M Magnesium Chloride B12. 20% iso-Propanol, 0.1 M Na Acetate pH 4.6, 0.2 M Calcium Chloride C1. 1.0 M Sodium Acetate, 0.1 M

Hill, Chris

92

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

93

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

PubMed

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

Larkindale, Jane; Huang, Bingru

2004-04-01

94

Chloride-induced release of actively loaded calcium from light and heavy sarcoplasmic reticulum vesicles  

Microsoft Academic Search

Summary Light and heavy sarcoplasmic reticulum vesicles (LSR, HSR) isolated from rabbit leg muscle have been used in a study of chloride-induced Ca2+ release. The biochemical and morphological data indicate that LSR is derived from the longitudinal reticulum and HSR is derived from the terminal cisternae of the sarcoplasmic reticulum. LSR and HSR were both able to accumulate Ca2+ in

Kevin P. Campbellê; Adil E. Shamooêê

1980-01-01

95

Elastic properties of stishovite and the CaCl2-type silica at the mantle temperature and pressure: An ab initio investigation  

NASA Astrophysics Data System (ADS)

The elastic constant tensors of stishovite and the CaCl2-type silica at the Earth's mantle temperature and pressure were determined using first-principles calculations with local density approximation. The elastic properties of stishovite show not only strong pressure dependence but also temperature dependence. By increasing temperature, the shear instability of stishovite is shifted to an elevated pressure with a slope of ?5.4±1.4 MPa/K. The softening of the shear modulus and the positive Clapeyron slope result in crossing of the sound velocities at different temperatures, which leads to the unusual positive temperature dependence of the sound velocities around the phase boundary. The transition from stishovite to the CaCl2-type silica at the lower mantle's temperature occurs at a depth far deeper than 1200 km and is accompanied by a velocity jump of ?0.98±0.08 km/s in S wave velocity (VS) and ?0.45±0.15 km/s in P wave velocity (VP). This transition is likely related to the seismic discontinuity at the depth of ?1670 km in the vicinity of Mariana Island. The unusual positive temperature dependence of VS of stishovite and strong anisotropy of stishovite and the CaCl2-type silica around the phase boundary provide potential ways to identify the origin of the seismic discontinuity.

Yang, Rui; Wu, Zhongqing

2014-10-01

96

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

National Technical Information Service (NTIS)

In conditions where tight crevices exist in hot chloride containing solutions Alloy 22 may suffer crevice corrosion. The occurrence (or not) of crevice corrosion in a given environment (e.g. salt concentration and temperature), is governed by the values o...

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

2006-01-01

97

In vitro fertilization in inbred BALB/c mice II: effects of lactate, osmolarity and calcium on in vitro capacitation.  

PubMed

To elucidate requirements for in vitro sperm capacitation in inbred BALB/c mice, osmolarity, calcium and lactate were optimized using modified simplex optimization medium (mKSOM). Modified human tubal fluid (mHTF), a capacitation-supporting medium, was used as a control. In the first series of experiments, the effects of calcium and osmolarity were studied in the presence of lactate. Although preincubation with >or=5 mM CaCl2 improved fertilization after insemination significantly, it was still significantly lower than incubation with mHTF. To obtain fertilization at the equivalent levels to that of mHTF, isotonic osmolarity (305 mOsmol) was required. Trehalose, an osmotic reagent, could substitute for NaCl partially. In the second series of experiments, the effects of lactate were examined using a concentration of 5 mM calcium and isotonic osmolarity. Preincubation with 75%), as well as the percentages of B (capacitated) pattern sperm (>or=40%) in chlortetracycline (CTC) staining, as compared with incubation in mHTF (46% and 28%, respectively; p<0.05). In the third series of experiments, the effects of osmolarity and calcium in the absence of lactate were examined. An increase in osmolarity during sperm preincubation increased both fertilization and B-pattern sperm significantly in a dose-dependent manner. Trehalose, sucrose and choline chloride could substitute for NaCl. An increase in CaCl2 concentration during preincubation had no effect on fertilization, but this increase reduced the percentages of B-pattern sperm. In vitro capacitation of inbred BALB/c mice is sensitive to lactate and osmolarity, but that sensitivity for calcium varies depending on the presence or absence of lactate. PMID:18578945

Kito, Seiji; Ohta, Yuki

2008-08-01

98

Response of dog parathyroid glands to short-term alterations of serum calcium  

Microsoft Academic Search

Parathyroid (PT) glands of dogs were exposed to low or high serum calcium by infusion of either EGTA or CaCl2. Infusion of EGTA resulted in an increase of parathyroid hormone (PTH) and infusion of CaCl2, in a decrease of this hormone. The PT glands excised either at the beginning or at the end of the infusions were examined by electron

P. Wild; M. Becker

1980-01-01

99

Effect of NaCl and CaCl 2 on the antioxidant mechanism of leaves and stems of the rootstock CAB6P ( Prunus cerasus L.) under in vitro conditions  

Microsoft Academic Search

The effect of salinity on the non-enzymic and enzymic antioxidant activity, shoot proliferation and nutrient accumulation\\u000a was studied in in vitro cultures of the rootstock CAB-6P (Prunus cerasus L.). Three concentrations (0, 30 and 60 mM) of NaCl or CaCl2 were added to a modified MS medium. Between the two salt treatments used, only the explants treated with CaCl2 presented significant

C. Chatzissavvidis; G. Veneti; I. Papadakis; I. Therios

2008-01-01

100

Thermal stability of plasticized poly(vinyl chloride) compounds stabilized with pre-heated mixtures of calcium and\\/or zinc stearates  

Microsoft Academic Search

Processing and post-processing thermal stability of poly(vinyl chloride) compounds, plasticized with di(ethyl hexyl) phthalate (DEHP) and epoxidized soybean oil (ESO), using several ratios of calcium\\/zinc stearates are reported here. Two series of compounds were prepared, varying the DEHP or ESO concentrations. The compounds were prepared as follows: (1) preheating stearates, (2) dry-blending the compound components, (3) pelletizing the dry-blend and

Luis J. González-Ortiz; Martín Arellano; Carlos F. Jasso; Eduardo Mendizábal; M. Judith Sánchez-Peña

2005-01-01

101

Improved fertility in gilts and sows after artificial insemination of frozen-thawed boar semen by supplementation of semen extender with caffeine and CaCl2.  

PubMed

Supplementation of semen extender with caffeine and CaCl(2) for artificial insemination (AI) of fresh spermatozoa has been demonstrated to reduce recruitment of uterine polymorphonuclear leukocytes (PMNs) and the activity of phagocytosis. Here, we determined if addition of caffeine and CaCl(2) to semen extender improves the fertility of frozen-thawed boar semen. In experiment 1, gilts were cervically inseminated twice with frozen-thawed boar spermatozoa (25 x 10(8) cells per dose) suspended in Modena solution (n=7) or modified Beltsville Thawing Solution supplemented with caffeine and CaCl(2) (BCC, n=7). The gilts were slaughtered 4 h later, and their oviducts and uterine horns plus the body of the uterus were flushed to recover PMNs and non-phagocytosed spermatozoa. There was no difference in the total number of uterine PMNs between gilts inseminated with Modena solution and those inseminated with BCC (3.8 x 10(8) vs. 1.5 x 10(8) cells, respectively); however, the total number of uterine spermatozoa was higher when gilts were inseminated with BCC (40.6 x 10(6) cells) compared with those inseminated with Modena solution (1.4 x 10(6) cells, P<0.05). In experiment 2, gilts and sows were subjected to intrauterine insemination twice with frozen-thawed spermatozoa suspended (25 x 10(8) sperm per dose) in Modena (n=21) or BCC (n=21). The overall pregnancy and farrowing rates were higher in females inseminated with BCC (71.4 and 61.9%, respectively) compared with those inseminated with Modena solution (38.1 and 28.6%, respectively, P<0.05). However, no significant difference in litter size of piglets was observed between treatments (7.2 +/- 1.6 piglets for Modena solution vs. 8.2 +/- 0.9 piglets for BCC solution). In conclusion, we demonstrated that use of BCC solution for frozen-thawed boar semen produced better pregnancy and farrowing rates following AI than Modena solution, probably by reducing the phagocytosis of spermatozoa. PMID:19734696

Yamaguchi, Shoichiro; Funahashi, Hiroaki; Murakami, Tetsuya

2009-12-01

102

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

PubMed

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

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

2014-07-29

103

Bile acids stimulate chloride secretion through CFTR and calcium-activated Cl- channels in Calu-3 airway epithelial cells.  

PubMed

Bile acids resulting from the aspiration of gastroesophageal refluxate are often present in the lower airways of people with cystic fibrosis and other respiratory distress diseases. Surprisingly, there is little or no information on the modulation of airway epithelial ion transport by bile acids. The secretory effect of a variety of conjugated and unconjugated secondary bile acids was investigated in Calu-3 airway epithelial cells grown under an air-liquid interface and mounted in Ussing chambers. Electrogenic transepithelial ion transport was measured as short-circuit current (Isc). The taurine-conjugated secondary bile acid, taurodeoxycholic acid (TDCA), was found to be the most potent modulator of basal ion transport. Acute treatment (5 min) of Calu-3 cells with TDCA (25 ?M) on the basolateral side caused a stimulation of Isc, and removal of extracellular Cl(-) abolished this response. TDCA produced an increase in the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent current that was abolished by pretreatment with the CFTR inhibitor CFTRinh172. TDCA treatment also increased Cl(-) secretion through calcium-activated chloride (CaCC) channels and increased the Na(+)/K(+) pump current. Acute treatment with TDCA resulted in a rapid cellular influx of Ca(2+) and increased cAMP levels in Calu-3 cells. Bile acid receptor-selective activation with INT-777 revealed TGR5 localized at the basolateral membrane as the receptor involved in TDCA-induced Cl(-) secretion. In summary, we demonstrate for the first time that low concentrations of bile acids can modulate Cl(-) secretion in airway epithelial cells, and this effect is dependent on both the duration and sidedness of exposure to the bile acid. PMID:24993131

Hendrick, Siobhán M; Mroz, Magdalena S; Greene, Catherine M; Keely, Stephen J; Harvey, Brian J

2014-09-01

104

Calcium  

MedlinePLUS

... it from: Dairy products. Low-fat milk, yogurt, cheese, and cottage cheese are good sources of calcium. Veggies. You'll ... burritos or wraps. Fill them with eggs and cheese for breakfast; turkey, cheese, lettuce, tomato, and light ...

105

Shape-controlled production of biodegradable calcium alginate gel microparticles using a novel microfluidic device.  

PubMed

In this paper we describe a novel method of manufacturing shape-controlled calcium alginate gel microparticles in a microfluidic device. Both manufacturing shape-controlled microparticles and synthesizing hydrogel microparticles could be performed simultaneously in the microfluidic device. The novel microfluidic device comprised of two individual flow-focusing channels and a synthesizing channel was successfully applied as a continuous microfluidic reactor to synthesize gel microparticles with size and shape control. By passive control based on the microchannel geometric confinement and liquid-phase flow rates, we succeeded in producing monodisperse sodium alginate microparticles with diverse shapes (such as plugs, disks, microspheres, rods, and threads) in the flow-focusing channels of the microfluidic device. The shape and size of the sodium alginate microparticles could be tuned by adjusting the flow rates of the various streams. Further stages of the chemical reaction could be initiated by mixing sodium alginate microparticles and calcium chloride (CaCl2) solution in the synthesizing channel. The shapes of the sodium alginate microparticles could be permanently preserved by the synthesis of calcium alginate gel microparticles. The preparation conditions of size- and shape-controlled calcium alginate microparticles and influence factors were studied. PMID:17042568

Liu, Kan; Ding, Hui-Jiang; Liu, Jing; Chen, Yong; Zhao, Xing-Zhong

2006-10-24

106

Calcium-induced tertiary structure modifications of endo-?-1,3-glucanase from Pyrococcus furiosus in 7.9 M guanidinium chloride  

PubMed Central

The family 16 endo-?-1,3 glucanase from the extremophilic archaeon Pyrococcus furiosus is a laminarinase, which in 7.9 M GdmCl (guanidinium chloride) maintains a significant amount of tertiary structure without any change of secondary structure. The addition of calcium to the enzyme in 7.9 M GdmCl causes significant changes to the near-UV CD and fluorescence spectra, suggesting a notable increase in the tertiary structure which leads to a state comparable, but not identical, to the native state. The capability to interact with calcium in 7.9 M GdmCl with a consistent recovery of native tertiary structure is a unique property of this extremely stable endo-?-1,3 glucanase. The effect of calcium on the thermodynamic parameters relative to the GdmCl-induced equilibrium unfolding has been analysed by CD and fluorescence spectroscopy. The interaction of calcium with the native form of the enzyme is studied by Fourier-transform infrared spectroscopy in the absorption region of carboxylate groups and by titration in the presence of a chromophoric chelator. A homology-based model of the enzyme is generated and used to predict the putative binding site(s) for calcium and the structural interactions potentially responsible for the unusual stability of this protein, in comparison with other family 16 glycoside hydrolases. PMID:15482259

2004-01-01

107

Effect of Oat Bran Muffins on Calcium Absorption and Calcium, Phosphorus, Magnesium and Zinc Balance in Men1»2  

Microsoft Academic Search

Metabolic balance studies were conducted in adult human males to investigate the effect of oat bran on the nitrogen, calcium, phosphorus, magnesium and zinc balance, on the intestinal absorption of calcium and on the endogenous fecal calcium, using 47CaCl2as the tracer. A 40-d control period preceded a 32-d experi mental period in which subjects consumed four oat bran muffins dairy

HERTA SPENCER; CLEMONTAIN MORRIS; JEANINE DERLER; DACE OSIS

108

Forty mouse strain survey of voluntary calcium intake, blood calcium, and bone mineral content  

PubMed Central

We measured voluntary calcium intake, blood calcium, and bone mineral content of male and female mice from 40 inbred strains. Calcium intakes were assessed using 48-h two-bottle tests with a choice between water and one of the following: water, 7.5, 25, and 75 mM CaCl2, then 7.5, 25, and 75 mM calcium lactate (CaLa). Intakes were affected by strain, sex, anion, and concentration. In 11 strains females consumed more calcium than did males and in the remaining 29 strains there were no sex differences. Nine strains drank more CaLa than CaCl2 whereas only one strain (JF1/Ms) drank more CaCl2 than CaLa. Some strains had consistently high calcium intakes and preferred all calcium solutions relative to water (e.g., PWK/PhJ, BTBR T+tf/J, JF1/Ms). Others had consistently low calcium intakes and avoided all calcium solutions relative to water (e.g., KK/H1J, C57BL/10J, CE/J, C58/J). After behavioral tests, blood was sampled and assayed for pH, ionized calcium concentration, and plasma total calcium concentration. Bone mineral density and content were assessed by DEXA. There were no significant correlations between any of these physiological measures and calcium intake. However, strains of mice that had the highest calcium intakes generally fell at the extremes of the physiological distributions. We conclude that the avidity for calcium is determined by different genetic architecture and thus different physiological mechanisms in different strains. PMID:17493644

Tordoff, Michael G.; Bachmanov, Alexander A.; Reed, Danielle R.

2007-01-01

109

A glass-encapsulated calcium phosphate wasteform for the immobilization of actinide-, fluoride-, and chloride-containing radioactive wastes from the pyrochemical reprocessing of plutonium metal  

NASA Astrophysics Data System (ADS)

Chloride-containing radioactive wastes are generated during the pyrochemical reprocessing of Pu metal. Immobilization of these wastes in borosilicate glass or Synroc-type ceramics is not feasible due to the very low solubility of chlorides in these hosts. Alternative candidates have therefore been sought including phosphate-based glasses, crystalline ceramics and hybrid glass/ceramic systems. These studies have shown that high losses of chloride or evolution of chlorine gas from the melt make vitrification an unacceptable solution unless suitable off-gas treatment facilities capable of dealing with these corrosive by-products are available. On the other hand, both sodium aluminosilicate and calcium phosphate ceramics are capable of retaining chloride in stable mineral phases, which include sodalite, Na 8(AlSiO 4) 6Cl 2, chlorapatite, Ca 5(PO 4) 3Cl, and spodiosite, Ca 2(PO 4)Cl. The immobilization process developed in this study involves a solid state process in which waste and precursor powders are mixed and reacted in air at temperatures in the range 700-800 °C. The ceramic products are non-hygroscopic free-flowing powders that only require encapsulation in a relatively low melting temperature phosphate-based glass to produce a monolithic wasteform suitable for storage and ultimate disposal.

Donald, I. W.; Metcalfe, B. L.; Fong, S. K.; Gerrard, L. A.; Strachan, D. M.; Scheele, R. D.

2007-03-01

110

The roles of calcium-sensing receptor and calcium channel in osteogenic differentiation of undifferentiated periodontal ligament cells.  

PubMed

Elevated extracellular calcium has been shown to promote the differentiation of osteoblasts. However, the way that calcium affects the osteogenic differentiation of human periodontal ligament stem/progenitor cells (PDLSCs) remains unclear. Our aim has been to investigate the proliferation and osteogenic differentiation of a calcium-exposed human PDLSC line (cell line 1-17) that we have recently established and to elucidate the roles of the calcium-sensing receptor (CaSR) and L-type voltage-dependent calcium channel (L-VDCC) in this process. Proliferation activity was investigated by WST-1 assay, and gene and protein expression was examined by quantitative reverse transcriptase plus the polymerase chain reaction and immunostaining, respectively. Calcification assay was performed by von Kossa and Alizarin red staining. Treatment with 5 mM CaCl2 significantly induced proliferation, bone-related gene expression, and calcification in cell line 1-17. During culture with 5 mM CaCl2, this cell line up-regulated the gene expression of CaSR, which was reduced after 7 days. Simultaneous treatment with NPS2143, a CaSR inhibitor, and calcium significantly further increased bone-related gene expression and calcification as compared with CaCl2 exposure alone. The L-VDCC inhibitor, nifedipine, significantly suppressed osteogenic differentiation of cell line 1-17 treated with 5 mM CaCl2 and promoted the expression of CaSR, as compared with calcium treatment alone. Thus, elevated extracellular calcium promotes the proliferation and osteogenic differentiation of a PDLSC line. Antagonizing CaSR further enhances the effect of calcium on osteogenic differentiation, with CaSR expression being regulated by L-VDCC under extracellular calcium. Extracellular calcium might therefore modulate the osteogenic differentiation of PDLSCs through reciprocal adjustments of CaSR and L-VDCC. PMID:24842051

Koori, Katsuaki; Maeda, Hidefumi; Fujii, Shinsuke; Tomokiyo, Atsushi; Kawachi, Giichiro; Hasegawa, Daigaku; Hamano, Sayuri; Sugii, Hideki; Wada, Naohisa; Akamine, Akifumi

2014-09-01

111

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

SciTech Connect

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

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

1999-01-01

112

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

SciTech Connect

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

Prabhat K. Tripathy; Derek J. Fray

2011-11-01

113

Angiotensin II modulates mouse skeletal muscle resting conductance to chloride and potassium ions and calcium homeostasis via the AT1 receptor and NADPH oxidase.  

PubMed

Angiotensin II (ANG II) plays a role in muscle wasting and remodeling; however, little evidence shows its direct effects on specific muscle functions. We presently investigated the acute in vitro effects of ANG II on resting ionic conductance and calcium homeostasis of mouse extensor digitorum longus (EDL) muscle fibers, based on previous findings that in vivo inhibition of ANG II counteracts the impairment of macroscopic ClC-1 chloride channel conductance (gCl) in the mdx mouse model of muscular dystrophy. By means of intracellular microelectrode recordings we found that ANG II reduced gCl in the nanomolar range and in a concentration-dependent manner (EC50 = 0.06 ?M) meanwhile increasing potassium conductance (gK). Both effects were inhibited by the ANG II receptors type 1 (AT1)-receptor antagonist losartan and the protein kinase C inhibitor chelerythrine; no antagonism was observed with the AT2 antagonist PD123,319. The scavenger of reactive oxygen species (ROS) N-acetyl cysteine and the NADPH-oxidase (NOX) inhibitor apocynin also antagonized ANG II effects on resting ionic conductances; the ANG II-dependent gK increase was blocked by iberiotoxin, an inhibitor of calcium-activated potassium channels. ANG II also lowered the threshold for myofiber and muscle contraction. Both ANG II and the AT1 agonist L162,313 increased the intracellular calcium transients, measured by fura-2, with a two-step pattern. These latter effects were not observed in the presence of losartan and of the phospholipase C inhibitor U73122 and the in absence of extracellular calcium, disclosing a Gq-mediated calcium entry mechanism. The data show for the first time that the AT1-mediated ANG II pathway, also involving NOX and ROS, directly modulates ion channels and calcium homeostasis in adult myofibers. PMID:25080489

Cozzoli, Anna; Liantonio, Antonella; Conte, Elena; Cannone, Maria; Massari, Ada Maria; Giustino, Arcangela; Scaramuzzi, Antonia; Pierno, Sabata; Mantuano, Paola; Capogrosso, Roberta Francesca; Camerino, Giulia Maria; De Luca, Annamaria

2014-10-01

114

Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.  

ERIC Educational Resources Information Center

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)

Henrickson, Charles H.; Robinson, Paul R.

1979-01-01

115

Quality Attributes of Halva by Utilization of Proteins, Non-hydrogenated Palm Oil, Emulsifiers, Gum Arabic, Sucrose, and Calcium Chloride  

Microsoft Academic Search

Emulsion stability (oil separation) in halva is a major problem that affects quality upon storage. Emulsion instability results in toughness, oil separation, and oil contamination on packaging materials. The objective of this study was to evaluate the effectiveness of improving halva quality by incorporating non-hydrogenated palm oil, glycerol, soy protein concentrate, gelatin, lecithin, pectin, gum Arabic, sugar powder, and calcium

K. I. Ereifej; T. M. Rababah; M. A. Al-Rababah

2005-01-01

116

The effect of CaCl 2 on growth rate, wood decay and oxalic acid accumulation in Serpula lacrymans and related brown-rot fungi  

Microsoft Academic Search

The dry rot fungus, Serpula lacrymans, is one of the most destructive copper-tolerant fungi causing timber decay in buildings in temperate regions. Calcium and oxalic acid have been shown to play important roles in the mecha­ nism of wood decay. The effect of calcium on growth and decay was evaluated for 12 strains of S. lacrymans and compared to five

Anne Christine Steenkjær Hastrup; Bo Jensen; Carol Clausen; Frederick Green III

2006-01-01

117

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

Microsoft Academic Search

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

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

2008-01-01

118

Enzyme-catalysed synthesis of calcium phosphates  

Microsoft Academic Search

A biomimetic method is described for the precipitation of nanosized calcium phosphates using the alkaline phosphatase (EC\\u000a 3.1.3.1), which is responsible for hydrolysis of organic and inorganic phosphates in vivo. Buffered solutions containing glycerol-2-phosphate\\u000a and CaCl2 in addition to MgCl2 and the respective enzyme were prepared for calcium phosphate precipitation. The phosphate group of glycerol-2-phosphate\\u000a was cleaved through enzymatic hydrolysis. The

Christiane Hoffmann; Cordt Zollfrank; Günter Ziegler

2008-01-01

119

[Influence of rhizobial (Rhizobium leguminosarum) inoculation and calcium ions on the NADPH oxidase activity in roots of etiolated pea (Pisum sativum L.) seedlings].  

PubMed

Changes in the functional activity of the NADPH oxidase in the microsomal fraction of roots of etiolated pea seedlings, caused by rhizobial inoculation and calcium ions (Ca2+), are shown. The enzyme activity in a medium with an exogenous source of Ca2+ (CaCl2, 100 microM) fluctuated, increasing 5 to 20 min and decreasing 10 and 30 min after addition. A calcium chelator (ethylene glycol tetraacetic acid (EDTA), 100 microM) potentiated the decrease in the enzyme activity in the presence of exogenous calcium. Rhizobial inoculation caused a 3.9-fold increase in the enzyme activity 5 min after inoculation compared to the control (without inoculation). The Ca(2+)-channel activator (amiodarone, 300 microM) and the Ca(2+)-channel blocker (lanthanum chloride, 400 microM) reduced the NADPH oxidase activity after rhizobial inoculation compared to the control level (without inoculation). It is concluded that Ca2+ and reactive oxygen species are involved in the regulation of the membrane NADPH oxidase activity in roots of pea seedlings. PMID:23882941

Glian'ko, A K; Ishchenko, A A

2013-01-01

120

The Porcine Chloride Channel Calcium-Activated Family Member pCLCA4a Mirrors Lung Expression of the Human hCLCA4  

PubMed Central

Pig models of cystic fibrosis (CF) have recently been established that are expected to mimic the human disease closer than mouse models do. The human CLCA (originally named chloride channels, calcium-activated) member hCLCA4 is considered a potential modifier of disease severity in CF, but its murine ortholog, mCLCA6, is not expressed in the mouse lung. Here, we have characterized the genomic structure, protein processing, and tissue expression patterns of the porcine ortholog to hCLCA4, pCLCA4a. The genomic structure and cellular protein processing of pCLCA4a were found to closely mirror those of hCLCA4 and mCLCA6. Similar to human lung, pCLCA4a mRNA was strongly expressed in porcine lungs, and the pCLCA4a protein was immunohistochemically detected on the apical membranes of tracheal and bronchial epithelial cells. This stands in sharp contrast to mouse mCLCA6, which has been detected exclusively in intestinal epithelia but not the murine lung. The results may add to the understanding of species-specific differences in the CF phenotype and support the notion that the CF pig model may be more suitable than murine models to study the role of hCLCA4. PMID:22205680

Plog, Stephanie; Grötzsch, Tanja; Klymiuk, Nikolai; Kobalz, Ursula; Gruber, Achim D.

2012-01-01

121

Internal pressures and molecular dimensions in aqueous solutions of some chlorides  

NASA Technical Reports Server (NTRS)

On the basis of measurements of the velocity of ultrasounds in aqueous solutions of some alkaline-earth chlorides (MgCl2, CaCl2, BaCl2) the concentration and temperature dependences of the internal pressure were determined. Using these results, as well as surface tension measurements, the mean diameters of the molecular species as a function of concentration and temperature, were determined.

Auslaender, D.; Lenart, I.; Rus, E.; Ciupe, A.

1974-01-01

122

Electrochemistry of lithium\\/metal sulfide and calcium\\/metal sulfide cells using molten salt electrolytes  

Microsoft Academic Search

The electrochemical properties of lithium\\/LiCl-KCl\\/metal sulfide and calcium\\/LiCl-KCl CaCl2\\/metal sulfide cells are described. These cells, which operate at about 700 K, employ intermetallic compounds (rather than elemental lithium or calcium) as their negative electrodes; the positive electrodes are usually iron sulfides, but a variety of other transition metal sulfides have also been tested in lithium cells. The cells with the

R. K. Steunenberg; M. F. Roche

1977-01-01

123

The microsporidian spore invasion tube. II. Role of calcium in the activation of invasion tube discharge  

PubMed Central

A swelling response by the polaroplast organelle initiated microsporidian invasion tube extrusions by Glugea hertwigi spores. The tumescence was induced by the displacement of internal calcium. Sodium citrate, phosphate, and the calcium ionophore A23187 were effective in initiating polaroplast swelling and spore discharge; however, the addition of external CaCl2 switched the expanded polaroplasts to a contracted state and blocked spore discharge. Unlike CaCl2, equivalent concentrations of KCl, NaCl, MgCl2, and BaCl2 did not induced polaroplast contraction, and spore discharge was not blocked. 45CaCl2 readily incorporated into spores with expanded polaroplasts; however, little calcium uptake was apparent in spores with contracted polaroplasts. Metallochromic arsenazo III yielded a color spectrum characteristic of the dye-Ca++ complex in the polaroplast region; furthermore, a membrane association with calcium was indicated by strong chlorotetracycline fluorescence within the polaroplast; this fluorescence was extinguished by pretreating spores with ionophore A23187. An association of the membrane with calcium was also indicated by a potassium ferrocyanide-osmium tetroxide technique. All evidence indicates that an internal calcium displacement is an important initial step in the swelling response of the polaroplast organelle. PMID:6811603

1982-01-01

124

Similar vasoconstrictor responses to calcium in normotensive and esssential hypertensive men.  

PubMed

To study limb vascular responses in man to elevations in plasma calcium concentrations, we infused test isosmolar solutions of CaCl2 (0.115, 0.230, and 0.460 meq calcium/min) and NaCl and control isosmolar solutions of NaCl into the brachial arteries of 10 normotensive men and eight men with essential hypertension of mild to moderate severity. Limb blood pressures were monitored, limb blood flow was measured by indicator-dilution, and limb vascular resistance was calculated as mm Hg/ml flow/min/100 cm3 limb volume. Measured concentration of calcium in limb venous plasma during infusion of 0.460 meq calcium/min was 11.5 +/- 0.8 meq/liter (mean +/- SEM) with individual values ranging up to 20 meq/liter. Changes in limb venous serum sodium, potassium, magnesium, and osmolality were similar during control and CaCl2 infusions. Decreases in limb venous blood hematocrit during CaCl2 infusions were the same or greater than those during control infusions. The infusions did not significantly change systemic blood calcium concentration or blood pressures. Limb blood flow decreased and resistance increased in response to CaCl2. Increments averaging as little as 2.2 meq/liter elevated limb resistance by about 45%. Log dose-response curves were linear. Responses did not differ in normotensives and hypertensives (P greater than 0.8). We conclude that the vascular response to acute elevation of plasma calcium concentrations up to 20 meq/liter in the limb oman is an impressive vasoconstriction. We found no evidence for abnormal vascular responses to calcium in essential hypertensive men. PMID:1098055

Overbeck, H W; Pamnani, M B; Derifield, R S

1975-06-01

125

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

Microsoft Academic Search

Leaf-sheath pulvini of excised segments from oat (Avena sativa L.) were induced to grow by treatment with 10 ?M indole-3-acetic acid (IAA), gravistimulation, or both, and the effects of\\u000a calcium, EGTA, and calcium channel blockers on growth were evaluated. Unilaterally applied calcium (10 mM CaCl2) significantly inhibited IAA-induced growth in upright pulvini but had no effect on growth induced by

Thomas G. Brock; James Burg; Najati S. Ghosheh; Peter B. Kaufman

1992-01-01

126

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

PubMed

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

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

2014-01-01

127

Experimental determination of REE fractionation between liquid and vapour in the systems NaCl-H2O and CaCl2-H2O up to 450 °C  

NASA Astrophysics Data System (ADS)

Fractionation of selected REE between brine and vapour was experimentally determined using a large-volume rocking Ti-autoclave that allowed quasi-isobaric sampling of liquid-vapour pairs. Samples were extracted along the 350, 400 and 450 °C-isotherms of the H2O-NaCl system, and along the 400 °C isotherm of the CaCl2 system. Total salt concentrations were either 6.6 and 10 wt% NaCl or CaCl2, respectively, and total REE concentrations were about 2 ppm of each REE. Starting pH at room temperature was 1.8, added as HCl. In another series of experiments, REEs were added in amounts of 312 ppm. Here, the starting pH at room temperature was 0.5, added as HNO3:HCl=1:2. Liquid-vapour pairs (L-V) were analysed for REE by ICP-MS methods. L-V-partitioning of REE along a particular isotherm follows broadly the partitioning of the main salt components, NaCl or CaCl2. DREE=REEV/REEL decrease rapidly from the critical point with decreasing pressure (equivalent to increasing salinity of the liquid) as the solvus opens. This is independent of the total amount of the added REE. Log DREE values show approximately linear correlations with decreasing pressure from the critical point to salt-saturated conditions where the L-V curve meets the liquid + vapour + solid boundary. At given P and T, we found a systematic variation of DREE along the La-Lu suite. HREE are enriched in the vapour phase relative to LREE. Fractionation coefficients KD=(HREEV/HREEL)/(LREEV/LREEL) increase linearly with ?P=Pcrit-P along a particular isotherm. At the 450 °C isotherm, KD (Lu/La) at the critical point (425 bar and 10 wt% NaCl) is 1; about 2.5 at 350 bar (33 wt% NaCl in the liquid); and about 5 if extrapolated to salt-saturation (250 bar and 52 wt% NaCl in the liquid). The REE fractionation behaviour is similar along the CaCl2-H2O solvus boundaries. Existing equations of state and thermodynamic databases of REE species cannot predict this behaviour at L-V-equilibrium conditions. That HREE are preferentially fractionated over LREE into the vapour phase has important petrogenetic consequences. In boiling hydrothermal systems, brines will be depleted in HREE relative to LREE. Isobaric cooling is ineffective for fractionation because the solvus closes and the system eventually shifts into the one-phase field. Fractionation is most effective in systems undergoing isothermal or adiabatic decompression. In an open system, where vapour may escape through cavities, fractionation is probably controlled by a Rayleigh fractionation process, resulting in larger overall fractionation effects. Similar fractionations probably occur during magma degassing at very shallow intrusion levels.

Shmulovich, Kirill; Heinrich, Wilhelm; Möller, Peter; Dulski, Peter

2002-09-01

128

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

PubMed

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

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

2012-06-01

129

Effect of different pre-treatments and dehydration methods on quality characteristics and storage stability of tomato powder  

Microsoft Academic Search

Dehydration process was carried out for tomato slices of var. Avinash after giving different pre-treatments such as calcium chloride (CaCl2), potassium metabisulphite (KMS), calcium chloride and potassium metabisulphite (CaCl2+KMS), and sodium chloride (NaCl). Untreated samples served as control. Solar drier and continuous conveyor (tunnel) drier were used for dehydration. Quality characteristics of tomato slices viz. moisture content, sugar, titratable acidity,

Mehdi Ghiafeh Davoodi; P. Vijayanand; S. G. Kulkarni; K. V. R. Ramana

2007-01-01

130

21 CFR 184.1191 - Calcium carbonate.  

Code of Federal Regulations, 2010 CFR

...chloride in the “Calcium chloride process”. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 46, which is incorporated by reference. Copies are available from the National Academy Press,...

2010-04-01

131

Two-dimensional electrophoretic analyses of cod (Gadus morhua, L.) whole muscle proteins, water-soluble fraction and surimi. Effect of the addition of CaCl2 and MgCl2 during the washing procedure.  

PubMed

Samples from pre- and post-rigor cod mince, surimi (a concentrate of fish myofibrillar proteins obtained after washing and dewatering the fish mince) and water from the first wash in the surimi manufacture, processed with and without the addition of 7.5 mM CaCl2 and 15 mM MgCl2, were analyzed by two-dimensional electrophoresis. The results showed that the main myofibrillar proteins, including myosin, actin and tropomyosin, remained in the surimi. Several other proteins were selectively removed during the washing procedure. Some additional major spots were detected in the two-dimensional gels containing samples of the wash water and surimi processed with the addition of Ca2+ and Mg2+ salts. These spots were either absent or present in minor amounts in the samples of post-rigor cod mince, wash water and surimi processed without Ca2+ and Mg2+ salts and in all the pre-rigor samples. This induced us to suggest that the new additional spots may constitute fragments of proteins originated by increased proteolytic activity during the surimi manufacture upon the addition of the Ca2+ and Mg2+ salts. Two-dimensional electrophoresis has proved to be a valuable tool to quickly and easily assess the effect of different processing conditions on the protein content of the products. PMID:1567921

Martinez, I; Solberg, C; Lauritzen, K; Ofstad, R

1992-01-01

132

Aqueous phase catalytic conversion of agarose to 5-hydroxymethylfurfural by metal chlorides  

SciTech Connect

Abstract: 5-HMF is a key intermediate for producing chemicals and fuels that can substitute for today’s petroleum-derived feedstocks. A series of metal chlorides, including NaCl, CaCl2, MgCl2, ZnCl2, CuCl2, FeCl3, and CrCl3, were comparatively investigated to catalyze agarose degradation for production of 5-HMF at temperature 180 oC, 200 oC, and 220 oC for 30 min, with catalyst concentration of 0.5% (w/w), 1% (w/w) and 5% (w/w), and substrate concentration of 2% (w/w). Our results revealed that alkali metal chlorides and alkali earth metal chlorides such as NaCl, CaCl2 and MgCl2 gave better 5-HMF yield compared with transition metal chlorides including ZnCl2, CrCl3, CuCl2 and FeCl3. 1% (w/w) MgCl2 was the more favorable catalyst for 5-HMF production from agarose, and resulted in 40.7% 5-HMF yield but no levulinic acid or lactic acid at 200 oC, 35 min. The reaction pathways of agarose degradation catalyzed by MgCl2 were also discussed.

Yan, Lishi; Laskar, Dhrubojyoti D.; Lee, Suh-Jane; Yang, Bin

2013-12-14

133

Preparation, mass diffusion, and biocompatibility analysis of porous-channel controlled calcium-alginate-gelatin hybrid microbeads for in vitro culture of NSCs.  

PubMed

The Ca-alginate/gelatin (CAG) microbeads were prepared and evaluated through assays for their mechanical strength, permeability, and the feasibility as a cell carrier for in vitro culture of neural stem cells. The effects of different concentrations of sodium alginate, gelatin, and calcium chloride on the mechanical strength of CAG microbeads were determined using a self-made puncture force tester. Following this, the microbeads were immersed in DMEM media for a specified period to test its decay resistance. A diffusion model including a calculation formula of diffusion coefficient was built to investigate the diffusion of glucose and bovine serum albumin (BSA) through the wall of the microbeads. Furthermore, the feasibility of the microbeads for in vitro culture was identified using neural stem cells from Kunming mouse. Through a systematic approach and comprehensive analysis, the optimal gelatin conditions for microbead preparation were determined; the final combination of parameters of 1.5 % (wt%) sodium alginate (SA), 0.5 % (wt%) gelatin, and 4 % (wt%) CaCl2 were the best conditions for NSC cultures. This experiment demonstrated that CAG microbeads had good cytocompatibility that made it suitable for the culture and successfully maintained stemness of neural stem cells. PMID:24728762

Song, Kedong; Li, Liying; Li, Ruipeng; Lim, Mayasari; Liu, Peng; Liu, Tianqing

2014-06-01

134

Secondary calcium solid electrolyte high temperature battery  

NASA Astrophysics Data System (ADS)

The application of polycrystalline Ca(2+) conducting beta-double prime alumina solid electrolytes to a new type of high temperature battery is investigated, experimentally. The negative electrode in the battery consisted of a calcium-silicon alloy whose redox electrochemistry was mediated by the solid electrolyte via molten salt eutectic CaCl2 (51.4 m/o), and CaI2 (mp 550 C). The molten salt and the calcium alloy material were separated from the positive active material via the Ca2 Ca(2+) conducting polycrystalline electrolyte. The positive electrode consisted of a solid-state matrix having related crystallographic structure. The electrochemical reversibility of the cells was measured at 580 C. The charge-discharge characteristics of the cells are plotted vs. time in a graph.

Sammells, A. F.; Schumacher, B.

1986-01-01

135

Cesium Chloride  

MedlinePLUS

... tachycardia after alternative treatment with cesium chloride for brain cancer. Mayo Clin Proc . 2004:79(8);1065-1069. ... Zero efficacy with cesium chloride self-treatment for brain cancer. Mayo Clin Proc. 2004;79:1588. Sartori HE. ...

136

Synthesis and thermal properties of strontium and calcium peroxides  

NASA Technical Reports Server (NTRS)

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

Philipp, Warren H.; Kraft, Patricia A.

1989-01-01

137

Influence of Calcium(II) and Chloride on the Oxidative Reactivity of a Manganese(II) Complex of a Cross-Bridged Cyclen Ligand.  

PubMed

Available data from different laboratories have confirmed that both Ca(2+) and Cl(-) are crucial for water oxidation in Photosystem II. However, their roles are still elusive. Using a manganese(II) complex having a cross-bridged cyclen ligand as a model, the influence of Ca(2+) on the oxidative reactivity of the manganese(II) complex and its corresponding manganese(IV) analogue were investigated. It has been found that adding Ca(2+) can significantly improve the oxygenation efficiency of the manganese(II) complex in sulfide oxidation and further accelerate the oxidation of sulfoxide to sulfone. Similar improvements have also been observed for Mg(2+), Sr(2+), and Ba(2+). A new monomeric manganese(IV) complex having two cis-hydroxide ligands has also been isolated through oxidation of the corresponding manganese(II) complex with H2O2 in the presence of NH4PF6. This rare cis-dihydroxomanganese(IV) species has been well characterized by X-ray crystallography, electrochemistry, electron paramagnetic resonance, and UV-vis spectroscopy. Notably, using the manganese(IV) complex as a catalyst demonstrates higher activity than the corresponding manganese(II) complex, and adding Ca(2+) further improves its catalytic efficiency. However, adding Cl(-) decreases its catalytic activity. In electrochemical studies of manganese(IV) complexes with no chloride ligand present, adding Ca(2+) positively shifted the redox potential of the Mn(IV)/Mn(III) couple but negatively shifted its Mn(V)/Mn(IV) couple. In the manganese(II) complex having a chloride ligand, adding Ca(2+) shifted both the Mn(IV)/Mn(III) and Mn(V)/Mn(IV) couples in the negative direction. The revealed oxidative reactivity and redox properties of the manganese species affected by Ca(2+) and Cl(-) may provide new clues to understanding their roles in the water oxidation process of Photosystem II. PMID:25375413

Zhang, Zhan; Coats, Katherine L; Chen, Zhuqi; Hubin, Timothy J; Yin, Guochuan

2014-11-17

138

Immobilization of ?-galactosidase by bioaffinity adsorption on concanavalin A layered calcium alginate–starch hybrid beads for the hydrolysis of lactose from whey\\/milk  

Microsoft Academic Search

Aspergillus oryzae ?-galactosidase was immobilized on the surface of a novel bioaffinity support: concanavalin A layered calcium alginate–starch beads. The maximum activity of the immobilized ?-galactosidase was obtained at 60°C, approximately 10 degrees higher than that of the free enzyme. The immobilized ?-galactosidase exhibited significantly higher stability to heat, urea, MgCl2, and CaCl2 than the free enzyme. An enhancement of

Toshiba Haider; Qayyum Husain

2009-01-01

139

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

PubMed

Calcium supplementation is a widely recognized strategy for achieving adequate calcium intake. We designed this blinded, randomized, crossover interventional trial to compare the bioavailability of a new stable synthetic amorphous calcium carbonate (ACC) with that of crystalline calcium carbonate (CCC) using the dual stable isotope technique. The study was conducted in the Unit of Clinical Nutrition, Tel Aviv Sourasky Medical Center, Israel. The study population included 15 early postmenopausal women aged 54.9?±?2.8 (mean?±?SD) years with no history of major medical illness or metabolic bone disorder, excess calcium intake, or vitamin D deficiency. Standardized breakfast was followed by randomly provided CCC or ACC capsules containing 192?mg elemental calcium labeled with (44) Ca at intervals of at least 3 weeks. After swallowing the capsules, intravenous CaCl2 labeled with (42) Ca on was administered on each occasion. Fractional calcium absorption (FCA) of ACC and CCC was calculated from the 24-hour urine collection following calcium administration. The results indicated that FCA of ACC was doubled (±?0.96 SD) on average compared to that of CCC (p?calcium supplementation. © 2014 American Society for Bone and Mineral Research. PMID:24753014

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

2014-10-01

140

EDTA-insoluble, calcium-binding proteoglycan in bovine bone  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

141

Calcium channel antagonism by pizotifen  

Microsoft Academic Search

Pizotifen is a clinically effective anti-migraine agent with potent anti-serotonin and anti-histamine properties. Pizotifen is equipotent in blocking contractions of the canine basilar artery induced by serotonin, norepinephrine or calcium chloride. As a result, the primary action of pizotifen in the canine basilar artery system appears to be calcium channel blockade and not selective antagonism of serotonin or norepinephrine. Calcium

S J Peroutka; S B Banghart; G S Allen

1985-01-01

142

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

Microsoft Academic Search

There are few data on the effects of mercury exposure on tissue concentrations of essential minerals. Male Sprague-Dawley rats were exposed to mercuric chloride and methylmercury chloride administered via the drinking water. Subsequently, the kidneys, spleen, liver, and brain were analyzed for mercury, calcium, copper, magnesium, manganese, iron, and zinc by atomic absorption spectrophotometry. Significant differences from controls were found

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

1980-01-01

143

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

E-print Network

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

Abdel-wahab, Ahmed Ibraheem Ali

2004-09-30

144

Calcium supplements  

MedlinePLUS

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

145

Effect of 14-deoxyandrographolide on calcium-mediated rat uterine smooth muscle contractility.  

PubMed

In this study, the effect of 14-deoxyandrographolide (14-DAP) on calcium channel-dependent rat uterine smooth muscle contraction was evaluated. Using a tissue bath preparation, 14-DAP was able to reduce the contractile response to 0.3 and 3.0 mm of CaCl(2), with an IC(50) of 1.24 +/- 0.23 x 10(-5) m and 5.94 +/- 0.29 x 10(-5) m, respectively. 14-DAP shifted the CaCl(2) cumulative dose response curve to the right, increasing the EC(50) from 2.08 +/- 0.20 x 10(-4) m to 4.22 +/- 0.22 x 10(-4) m (5 micrometer 14-DAP) and 2.5 +/- 1.0 x 10(-3) m (50 micrometer 14-DAP). In order to determine if 14-DAP had any effect on intracellular calcium, the relaxant response to 14-DAP following contraction by oxytocin, PGF(2alpha) and vanadate in Ca(+2)-free solution was compared with that of isoproterenol and phenylbutazone. While isoproterenol and phenylbutazone relaxed the smooth muscle in a dose-dependent manner, 14-DAP did not have any effect on either the oxytocin, PGF(2alpha) or vanadate-induced smooth muscle contraction. Based on these data, it appears that 14-DAP is an uterine smooth muscle relaxant which produces a selective blockade of voltage operated calcium channels. PMID:14595578

Burgos, Rafael A; Loyola, Mario; Hidalgo, María A; Labranche, Timothy P; Hancke, Juan L

2003-11-01

146

Influence of calcium sources on microbially induced calcium carbonate precipitation by Bacillus sp. CR2.  

PubMed

Stimulation of microbially induced calcium carbonate precipitation (MICCP) is likely to be influenced by calcium sources. In order to study such influences, we performed MICCP using Bacillus sp. CR2 in nutrient broth containing urea, supplemented with different calcium sources (calcium chloride, calcium oxide, calcium acetate and calcium nitrate). The experiment lasted 7 days, during which bacterial growth, urease activity, calcite production and pH were measured. Our results showed that calcium chloride is the better calcium source for MICCP process, since it provides higher urease activity and more calcite production. The influences of calcium sources on MICCP were further studied using Fourier transform-infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. These analyses confirmed that the precipitate formed was CaCO3 and composed of predominantly calcite crystals with a little amount of aragonite and vaterite crystals. The maximum yield of calcite precipitation was achievable with calcium chloride followed by calcium nitrate as a calcium source. The results of present study may be applicable to media preparation during efficient MICCP process. PMID:24643454

Achal, Varenyam; Pan, Xiangliang

2014-05-01

147

21 CFR 184.1193 - Calcium chloride.  

Code of Federal Regulations, 2010 CFR

...this chapter and for processed fruit and fruit juices as defined in § 170.3(n)(35) of this chapter; 0.32 percent for coffee and tea as defined in § 170.3(n)(7) of this chapter; 0.4 percent for condiments and relishes as defined in §...

2010-04-01

148

21 CFR 184.1193 - Calcium chloride.  

...this chapter and for processed fruit and fruit juices as defined in § 170.3(n)(35) of this chapter; 0.32 percent for coffee and tea as defined in § 170.3(n)(7) of this chapter; 0.4 percent for condiments and relishes as defined in §...

2014-04-01

149

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

PubMed

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

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

2013-12-01

150

Reduction of K+-stimulated 45Ca2+ influx in synaptosomes with age involves inactivating and noninactivating calcium channels and is correlated with temporal modifications in protein dephosphorylation.  

PubMed

The voltage-dependent calcium uptake in rat brain synaptosomes was measured under conditions in which [Ca2+]o/[Na+]i exchange was minimized to characterize the voltage-sensitive calcium channels from rats of different ages. In solutions of CaCl2 concentrations of less than 500 microM, the initial (5-s) calcium uptake declined by approximately 20-50% in 12- and 24-month-old rats relative to 3-month-old adults. Depolarization of synaptosomes from 3-month-old rats in a calcium-free medium or in the presence of 0.5 mM CaCl2 led to an exponential decline of the calcium uptake rate after 20 s (voltage- or voltage-and-calcium-dependent inactivation) to approximately 66 and 34% of the initial value with a t1/2 of 1.6 or 0.7 s, respectively. The presence of 1 microM nifedipine resulted in a 15-25% reduction of 45Ca2+ uptake rates, which appeared to affect noninactivating calcium channels, but addition of the calcium channel agonist Bay K 8644 was without effect. In 24-month-old rats, inactivation of 45Ca2+ uptake in calcium-free media was nondetectable, and in the presence of 0.5 mM CaCl2, the rate and extent of inactivation were also much lower than in 3-month-old animals (the t1/2 was 0.9 s, and the calcium uptake rate at 20 s was 55% of its initial value). Moreover, the presence of 1 microM nifedipine was without effect on initial calcium uptake or inactivation in synaptosomes from 24-month-old rats. These results indicate that the decrease in calcium channel-mediated 45Ca2+ uptake involves an inhibition or block of both dihydropyridine-resistant and -sensitive calcium channels.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2463338

Martínez-Serrano, A; Bogónez, E; Vitórica, J; Satrústegui, J

1989-02-01

151

[Calcium--essential for everybody].  

PubMed

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

Cichosz, Grazyna; Czeczot, Hanna

2014-06-01

152

Preparation and Sustained-Release Property of Triblock Copolymer/Calcium Phosphate Nanocomposite as Nanocarrier for Hydrophobic Drug  

NASA Astrophysics Data System (ADS)

The P123/ACP nanocomposite with sizes less than 100 nm consisting of triblock copolymer P123 and amorphous calcium phosphate (ACP) has been prepared by using an aqueous solution containing CaCl2, (NH4)3PO4, and P123 at room temperature. The P123/ACP nanocomposite is used as the nanocarrier for hydrophobic drug ibuprofen, based on the combined advantages of both amphiphilic block copolymer and calcium phosphate delivery system. The P123/ACP nanocomposite has a much higher ibuprofen loading capacity (148 mg/g) than the single-phase calcium phosphate nanostructures. The drug release percentage of the P123/ACP nanocomposite in simulated body fluid reaches about 100% in a period of 156 h, which is much slower than that of single-phase calcium phosphate nanostructures. It is expected that the P123/ACP nanocomposite is promising for the application in the controlled delivery of hydrophobic drugs.

Cao, Shao-Wen; Zhu, Ying-Jie; Wu, Jin; Wang, Ke-Wei; Tang, Qi-Li

2010-04-01

153

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

PubMed

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

Kizuki, Takashi; Matsushita, Tomiharu; Kokubo, Tadashi

2014-07-01

154

Furnace System Testing to Support Lower-Temperature Stabilization of High Chloride Plutonium Oxide Items at the Hanford Plutonium Finishing Plant  

SciTech Connect

High chloride content plutonium (HCP) oxides are impure plutonium oxide scrap which contains NaCl, KCl, MgCl2 and/or CaCl2 salts at potentially high concentrations and must be stabilized at 950 C per the DOE Standard, DOE-STD-3013-2000. The chlorides pose challenges to stabilization because volatile chloride salts and decomposition products can corrode furnace heating elements and downstream ventilation components. Thermal stabilization of HCP items at 750 C (without water washing) is being investigated as an alternative method for meeting the intent of DOE STD 3013-2000. This report presents the results from a series of furnace tests conducted to develop material balance and system operability data for supporting the evaluation of lower-temperature thermal stabilization.

Schmidt, Andrew J.; Gerber, Mark A.; Fischer, Christopher M.; Elmore, Monte R.

2003-04-16

155

Modulation of calcification of vascular smooth muscle cells in culture by calcium antagonists, statins, and their combination  

Microsoft Academic Search

Background Vascular calcification is an organized process in which vascular smooth muscle cells (VSMCs) are implicated primarily. The\\u000a purpose of the present study was to assess the effects of calcium antagonists and statins on VSMC calcification in vitro.\\u000a Methods VSMC calcification was stimulated by incubation in growth medium supplemented with 10 mmol\\/l ?-glycerophosphate, 8 mmol\\/l\\u000a CaCl2, 10 mmol\\/l sodium pyruvate, 1 ?mol\\/l insulin, 50 ?g\\/ml ascorbic

Astrid Trion; Cindy Schutte-Bart; Wilhelmina H. Bax; J. Wouter Jukema; Arnoud van der Laarse

2008-01-01

156

Germination of Bacterial Endospores with Calcium and Dipicolinic Acid  

Microsoft Academic Search

Aerobic and anaerobic bacterial endospores can be germinated if calcium chloride and dipicolinic acid are added to well-washed suspensions. Maximum germination is obtained when the calcium and acid are present in a molar ratio of one or more. This suggests that the 1:1 chelate of calcium and dipicolinic acid is the agent that induces germination.

Hans Riemann; Z. John Ordal

1961-01-01

157

Mechanistic characterization of chloride interferences in electrothermal atomization systems  

USGS Publications Warehouse

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

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

1988-01-01

158

Analytical models of calcium binding in a calcium channel  

NASA Astrophysics Data System (ADS)

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

Liu, Jinn-Liang; Eisenberg, Bob

2014-08-01

159

Identification of Quantitative Trait Loci Controlling High Calcium Response in Arabidopsis thaliana  

PubMed Central

Natural variation for primary root growth response to high Ca stress in Arabidopsis thaliana was studied by screening a series of accessions (ecotypes) under high Calcium (40 mM CaCl2 ) conditions. The genetic basis of this variation was further investigated by QTL analysis using recombinant inbred lines from Landsberg erecta (Ler)×Cape Verde Islands (Cvi) cross. Four QTLs were identified in chromosome 1, 2 and 5,and named response to high Calcium (RHCA) 1–4. The three QTLs (RHCA1, RHCA2 and RHCA4) were further confirmed by analysis of near isogenic lines harboring Cvi introgression fragments in Ler background. Real-time PCR analysis showed that several genes associated with high Ca response including SMT1 and XHT25 have changed expression pattern between Ler and near isogenic lines. These results were useful for detecting molecular mechanisms of plants for high Ca adaption. PMID:25401959

Li, Wenlong; Duan, Huikun; Chen, Fengying; Wang, Zhi; Huang, Xueqing; Deng, Xin; Liu, Yongxiu

2014-01-01

160

Inhibition of vascular calcium-gated chloride currents by blockers of KCa1.1, but not by modulators of KCa2.1 or KCa2.3 channels  

PubMed Central

Background and purpose: Recent pharmacological studies have proposed there is a high degree of similarity between calcium-activated Cl? channels (CaCCs) and large conductance, calcium-gated K+ channels (KCa1.1). The goal of the present study was to ascertain whether blockers of KCa1.1 inhibited calcium-activated Cl? currents (IClCa) and if the pharmacological overlap between KCa1.1 and CaCCs extends to intermediate and small conductance, calcium-activated K+ channels. Experimental approaches: Whole-cell Cl? and K+ currents were recorded from murine portal vein myocytes using the whole-cell variant of the patch clamp technique. CaCC currents were evoked by pipette solutions containing 500 nM free [Ca2+]. Key results: The selective KCa1.1 blocker paxilline (1 µM) inhibited IClCa by ?90%, whereas penitrem A (1 µM) and iberiotoxin (100 and 300 nM) reduced the amplitude of IClCa by ?20%, as well as slowing channel deactivation. Paxilline also abolished the stimulatory effect of niflumic acid on the CaCC. In contrast, an antibody against the Ca2+-binding domain of murine KCa1.1 had no effect on IClCa while inhibiting spontaneous KCa1.1 currents. Structurally different modulators of small and intermediate conductance calcium-activated K+ channels (KCa2.1 and KCa2.3), namely 1-EBIO, (100 µM); NS309, (1 µM); TRAM-34, (10 µM); UCL 1684, (1 µM) had no effect on IClCa. Conclusions and implications: These data show that the selective KCa1.1 blockers also reduce IClCa considerably. However, the pharmacological overlap that exists between CaCCs and KCa1.1 does not extend to the calcium-binding domain or to other calcium-gated K+ channels. PMID:19645713

Sones, WR; Leblanc, N; Greenwood, IA

2009-01-01

161

Calcium Carbonate  

MedlinePLUS

... heart. Calcium carbonate also is used as an antacid to relieve heartburn, acid indigestion, and upset stomach. ... use.Do not take calcium carbonate as an antacid for more than 2 weeks unless your doctor ...

162

Comparison of intrinsic and extrinsic tracer methods for estimating calcium bioavailability to rats from dairy foods  

SciTech Connect

Dairy products doubly labeled with 45Ca and 47Ca were used to evaluate an extrinsic labeling procedure for calcium bioavailability determination. Nonfat milk, yogurt, and fresh cheese curd were prepared from caprine milk that was intrinsically labeled with 45Ca. The products were then labeled extrinsically with 47Ca and administered to rats by gavage. The 47Ca to 45Ca ratio in bone and teeth averaged about 1.00 with either milk, yogurt, or CaCl2, but the ratio was about 1.04 when dosed with cheese curd. Ca absorption, determined by whole-body counting of 47Ca, was lower (P less than 0.05) in cheese curd (59%) than in either milk (69%), yogurt (72%), or CaCl2 (72%). Expressed as percent of dose, the absorption of 47Ca was highly correlated with bone 47Ca (r = 0.973) and with bone 45Ca (r = 0.946). Correlation between tibia 47Ca and tibia 45Ca was r = 0.923. For the dairy products tested, our results indicated that extrinsic 47Ca was absorbed similarly to intrinsic 45Ca. Moreover, the percent of radioactive dose retained in bone appears to be a valid indicator of relative bioavailability of food Ca.

Buchowski, M.S.; Sowizral, K.C.; Lengemann, F.W.; Van Campen, D.; Miller, D.D.

1989-02-01

163

Delay of Membrane Lipid Degradation by Calcium Treatment during Cabbage Leaf Senescence 1  

PubMed Central

Cabbage leaf discs (Brassica oleracea L., Capitata group) were floated adaxial side up in 0, 0.05, or 0.25 m CaCl2 solutions at 15°C for 14 d in the dark. To assess whether the delay of senescence by calcium treatment involved protection of membrane lipids, chlorophyll and protein content and the lipid composition of the membranes were determined during incubation. Chlorophyll and protein content decreased with time, in correlation with a reduction in the amount of phospholipids. The degree of unsaturation of phospholipids and free fatty acids decreased, whereas the ratio of sterol to phospholipid increased. The proportions of phospholipid classes did not change during senescence. The catabolism of phospholipids was delayed by 0.05 m calcium, but accelerated by 0.25 m, as compared to the untreated control. Based on the levels of the lipid intermediates, phospholipase D, phosphatidic acid phosphatase, lipolytic acyl hydrolase, and lipoxygenase appeared to be involved in the breakdown of phospholipids during senescence. Phospholipase D and phosphatidic acid phosphatase may be directly influenced by calcium. The calcium treatment apparently did not affect the activity of acyl hydrolase. Lipoxygenase, responsible for the peroxidation of the polyunsaturated fatty acids, was probably indirectly influenced by calcium. We conclude that the delay of senescence of cabbage leaf discs by calcium treatment involved protection of membrane lipids from degradation. PMID:16653181

Cheour, Foued; Arul, Joseph; Makhlouf, Joseph; Willemot, Claude

1992-01-01

164

Growth Performance, Carcass Characteristics and Plasma Mineral Chemistry as Affected by Dietary Chloride and Chloride Salts Fed to Broiler Chickens Reared under Phase Feeding System.  

PubMed

Requirements of dietary chloride (dCl) and chloride salts were determined by using 4×2 factorial arrangement under four phase feeding program. Four levels (0.31, 0.45, 0.59 and 0.73%) and two sources (NH4Cl and CaCl2) of the dCl were allocated to 1,472 chicks in eight dietary treatments in which each treatment was replicated four times with 46 birds per replicate. The four phase feeding program was comprised of four dietary phases: Prestarter (d 1 to 10), Starter (d 11 to 20), Grower (d 21 to 33) and Finisher (d 34 to 42); and diets were separately prepared for each phase. The cations, anions, pH, dissolved oxygen (DO), temperature, electrical conductivity (EC), total dissolved solids (TDS) and salinity were analyzed in drinking water and were not affected by dietary treatments. BW gain (BWG; p?0.009) and feed:gain (FG; p?0.03) were improved in CaCl2 supplemented diets during d 1 to 10. The maximum response of BWG and FG was observed at 0.38% and 0.42% dCl, respectively, for d 34 to 42. However, the level of dCl for BWG during d 21 to 33 (p?0.04) and d 34 to 42 (p?0.009) was optimized at 0.60% and 0.42%, respectively. The level of dCl for optimized feed intake (FI; p?0.006), FG (p?0.007) and litter moisture (LM; p?0.001) was observed at 0.60%, 0.38% and 0.73%, respectively, for d 1 to 42. Water intake (DWI) was not affected by increasing dCl supplementation (p>0.05); however, the ratio between DWI and FI (DWI:FI) was found highest at 0.73% dCl during d 1 to 10 (p?0.05) and d 21 to 33 (p?0.009). Except for d 34 to 42 (p?0.006), the increasing level of dCl did not result in a significant difference in mortality during any phase. Blood pH and glucose, and breast and thigh weights (percentage of dressed weight) were improved while dressing percentage (DP) and gastrointestinal health were exacerbated with NH4Cl as compared to CaCl2 supplemented diets (p?0.001). Higher plasma Na(+) and HCO3 (-) and lower Cl(-) and Ca(++) were observed in NH4Cl supplemented diets (p?0.001). Increasing supplementation of dCl increased plasma Cl(-) (p?0.04; quadratically) and linearly reduced plasma K(+) (p?0.001), Ca(++) (p?0.003), HCO3 (-) (p?0.001), and Na(+) (p?0.001; quadratically). Consequently, higher requirements of dietary chloride are suggested for feed intake; nevertheless, lower levels of dietary chloride are sufficient to support optimal BWG and FG with increasing age. The NH4Cl supplemented diets ameliorate breast and thigh meat yield along with overall energy balance (glucose). PMID:25049859

Mushtaq, M M H; Pasha, T N; Akram, M; Mushtaq, T; Parvin, R; Choi, H C; Hwangbo, J; Kim, J H

2013-06-01

165

Growth Performance, Carcass Characteristics and Plasma Mineral Chemistry as Affected by Dietary Chloride and Chloride Salts Fed to Broiler Chickens Reared under Phase Feeding System  

PubMed Central

Requirements of dietary chloride (dCl) and chloride salts were determined by using 4×2 factorial arrangement under four phase feeding program. Four levels (0.31, 0.45, 0.59 and 0.73%) and two sources (NH4Cl and CaCl2) of the dCl were allocated to 1,472 chicks in eight dietary treatments in which each treatment was replicated four times with 46 birds per replicate. The four phase feeding program was comprised of four dietary phases: Prestarter (d 1 to 10), Starter (d 11 to 20), Grower (d 21 to 33) and Finisher (d 34 to 42); and diets were separately prepared for each phase. The cations, anions, pH, dissolved oxygen (DO), temperature, electrical conductivity (EC), total dissolved solids (TDS) and salinity were analyzed in drinking water and were not affected by dietary treatments. BW gain (BWG; p?0.009) and feed:gain (FG; p?0.03) were improved in CaCl2 supplemented diets during d 1 to 10. The maximum response of BWG and FG was observed at 0.38% and 0.42% dCl, respectively, for d 34 to 42. However, the level of dCl for BWG during d 21 to 33 (p?0.04) and d 34 to 42 (p?0.009) was optimized at 0.60% and 0.42%, respectively. The level of dCl for optimized feed intake (FI; p?0.006), FG (p?0.007) and litter moisture (LM; p?0.001) was observed at 0.60%, 0.38% and 0.73%, respectively, for d 1 to 42. Water intake (DWI) was not affected by increasing dCl supplementation (p>0.05); however, the ratio between DWI and FI (DWI:FI) was found highest at 0.73% dCl during d 1 to 10 (p?0.05) and d 21 to 33 (p?0.009). Except for d 34 to 42 (p?0.006), the increasing level of dCl did not result in a significant difference in mortality during any phase. Blood pH and glucose, and breast and thigh weights (percentage of dressed weight) were improved while dressing percentage (DP) and gastrointestinal health were exacerbated with NH4Cl as compared to CaCl2 supplemented diets (p?0.001). Higher plasma Na+ and HCO3? and lower Cl? and Ca++ were observed in NH4Cl supplemented diets (p?0.001). Increasing supplementation of dCl increased plasma Cl? (p?0.04; quadratically) and linearly reduced plasma K+ (p?0.001), Ca++ (p?0.003), HCO3? (p?0.001), and Na+ (p?0.001; quadratically). Consequently, higher requirements of dietary chloride are suggested for feed intake; nevertheless, lower levels of dietary chloride are sufficient to support optimal BWG and FG with increasing age. The NH4Cl supplemented diets ameliorate breast and thigh meat yield along with overall energy balance (glucose). PMID:25049859

Mushtaq, M. M. H.; Pasha, T. N.; Akram, M.; Mushtaq, T.; Parvin, R.; Choi, H. C.; Hwangbo, J.; Kim, J. H.

2013-01-01

166

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

NASA Astrophysics Data System (ADS)

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

Sharp, Stephen R.

167

Mercuric chloride poisoning  

MedlinePLUS

Mercuric chloride is a very poisonous form of mercury. It is a type of mercury salt. There are ... mercury poisonings . This article discusses poisoning from swallowing mercuric chloride. This is for information only and not for ...

168

Relative bioavailability of calcium from calcium formate, calcium citrate, and calcium carbonate  

E-print Network

of calcium from calcium formate, a new experimental dietary calcium supplement, to that of calcium citrate and calcium carbonate. In a four-way crossover study, either a placebo or 1200 mg of calcium as calcium carbonate, calcium citrate, or calcium formate...

Hanzlik, Robert P.; Fowler, S. C.; Fisher, D. H.

2005-06-01

169

The binding of chloride ions by sulphate resistant portland cement  

Microsoft Academic Search

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

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

1995-01-01

170

The kinetics of the reaction of hydrogen chloride with fresh and spent Ca-based desulfurization sorbents  

Microsoft Academic Search

The absorption of hydrogen chloride by spent desulfurization sorbents containing calcium carbonate, calcium oxide and calcium hydroxide was investigated. The experiments were carried out in a fixed-bed reactor in two temperature ranges: 423–523 K for slaked lime and 673–873 K for limestone and quicklime. The spent Ca-based sorbents can still react with hydrogen chloride, and after calcining and slaking they

Wuyin Wang; Zhicheng Ye; Ingemar Bjerle

1996-01-01

171

Irrigation Water Quality Salinity Management  

E-print Network

Small Potassium sulfate K2SO4 Small Sodium bicarbonate NaHCO3 Small Calcium carbonate CaCO3 Very Small concentration as related to the concentration of calcium and magnesium, and 3 Irrigation Water Quality Standards Na2SO4 Moderate to large Calcium chloride CaCl2 Moderate Calcium sulfate (gypsum) CaSO4 2H2O Moderate

172

A study of the role of calcium and magnesium in casein micellar structure in human milk  

E-print Network

. , Texas ASM University; M. S. , Texas ASM University Chair of Advisory Committee: Dr. C. W. Dill The effects of EDTA, phosphatase hydrolysis, calcium chloride, and magnesium chloride on human casein micelles were observed using electron microscopy.... An increasing concentration of EDTA in the casein system dispersed more casein material, Phosphatase hydrolysis dispersed casein micellar material to a greater extent than the EDTA treatments alone. Calcium chloride reaggregated dispersed casein material...

Gallaway, Sheila Ann

2012-06-07

173

The calcium and the oxygen paradox: non-existent on the cellular level.  

PubMed

Ca2+-tolerant isolated adult heart cells can be exposed to 1 mM EGTA and then again to 1 mM CaCl2 without developing irreversible hypercontracture. Thus, they are not subject to the calcium paradox, even though they apparently become more permeable to Na+ during Ca2+-free incubation. When these cells are incubated anoxically without substrate they slowly lose their energetic reserves. The process resembles that of the arrested anoxic myocardium. The appearance of irreversibly hypercontracted cells is neither accompanied by a parallel increase in enzyme release nor by an aggravation of the anoxia-induced damage by reoxygenation. Thus these cells are not subject to the oxygen paradox. It is suggested that the differences between the myocytes' behaviour in tissue and in the isolated state are due to the fact that the isolated cells are free from mechanical interactions with adjacent cells. PMID:4062829

Piper, H M; Spahr, R; Hütter, J F; Spieckermann, P G

1985-01-01

174

Effect of calcium ion on Hydrilla verticillata thylakoid membrane O2 evolution.  

PubMed

Calcium ion-dependent reactivation of O2 evolution activity has been investigated in Hydrilla verticillata thylakoid preparations. Washing the thylakoids in calcium-free buffer or calcium-free buffer containing 1.5 M NaCl or 1.5 M NaCl plus 20% methanol, reversibly inhibited O2 evolution activity. The activity was restored on addition of calcium as calcium chloride and partially by strontium chloride. Immobilization of thylakoids with glutaraldehyde (GA) arrested the loss in O2 evolution activity caused by calcium-free high salt washing. However, calcium sensitivity was discernible in GA immobilized thylakoids subjected to calcium-free high salt washing. Since glutaraldehyde checks the loss of extrinsic thylakoid polypeptides due to washing, it is assumed that the calcium ion has regulatory functions in the photosynthetic electron transport, besides its interaction with thylakoid proteins. PMID:7642207

Mishra, S R; Sabat, S C

1995-04-01

175

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

NASA Technical Reports Server (NTRS)

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

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

2003-01-01

176

Improved Complexometric Determination of Calcium in Cheese  

Microsoft Academic Search

Accuracy and repeatability of com- plexometric methods for measuring cal- cium in cheese are limited by titration endpoints that are difficult to recognize. Much of this difficulty results from tur- bidity during titration. An alternative procedure is described in which 2 to 3 g of cheese are ashed, dissolved in dilute acid, and added calcium chloride is back titrated with

P. S. Kindstedt; F. V. Kosikowski

1985-01-01

177

Calcium orthophosphates  

PubMed Central

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

Dorozhkin, Sergey V.

2011-01-01

178

R u t c o r R e p o r t  

E-print Network

, RUTCOR and Department of Management Science and Information Systems, 94 Rockefeller Rd., Piscataway, NJ 08854 d Rutgers University, RUTCOR and Department of Management Science and Information Systems, 94) is a leading manufacturer and sup- plier in the global market of soda ash and calcium chloride (CaCl 2

179

Nanoindentation and storage of teeth  

Microsoft Academic Search

This study determined changes in nanomechanical properties of dentin and enamel during storage in deionized water, calcium chloride buffered saline solution and Hank's balanced salts solution (HBSS). Atomic force microscopy based nanoindentation showed that storing teeth in deionized water or CaCl2-solution resulted in a large decrease in elastic modulus and hardness. At 1 day a decrease in the mechanical properties

Stefan Habelitz; Grayson W. Marshall Jr.; Mehdi Balooch; Sally J. Marshall

2002-01-01

180

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

E-print Network

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

Minnesota, University of

181

Calcium antagonistic activity of Bacopa monniera in guinea-pig trachea  

PubMed Central

Objective: To demonstrate the calcium antagonistic property of ethanol extract of Bacopa monniera in guinea-pig trachea. Materials and Methods: The dose response curves of CaCl2 (1 × 10-5 to 1 × 10-1 M) were constructed in the absence and presence of ethanol extract of Bacopa monniera (100, 500 and 700 ?g/ml) or nifedipine (1 × 10-6 M) in guinea-pig trachea in calcium free high K+-MOPS-PSS (3-(N-morpholino)-propanesulphonic acid physiological salt solution). The data was analyzed by ANOVA followed by least significant difference test or by Student's ‘t’ test for unequal variance when appropriate. A probability of at least P < 0.05 was considered statistically significant. Results: The plant extract (500 and 700 ?g/ml) significantly (P < 0.05) depressed and shifted the calcium concentration-response curves (1 × 10-3- 1 × 10-1 M) to rightward similar to that of nifedipine. Conclusions: Bacopa monniera extract exhibited calcium channel blocking activity in guinea-pig tracheal smooth muscles that may rationalize its relaxant action on guinea-pig trachea and its traditional use in respiratory disorders. PMID:23087517

Channa, Shabana; Dar, Ahsana

2012-01-01

182

Strontium-89 Chloride  

MedlinePLUS

Your doctor has ordered the drug strontium-89 chloride to help treat your illness. The drug is given by injection into a vein or a catheter that ... Strontium-89 chloride is in a class of drugs known as radioisotopes. It delivers radiation to cancer ...

183

Rapid degradation of cyclooxygenase-1 and hematopoietic prostaglandin D synthase through ubiquitin-proteasome system in response to intracellular calcium level  

PubMed Central

Cyclooxygenase (COX)-1 and hematopoietic prostaglandin (PG) D synthase (H-PGDS) proteins, which are both involved in the arachidonate cascade, were stable in human megakaryocytic MEG-01 cells. In contrast, once the intracellular calcium level was increased by treatment with a calcium ionophore, both protein levels rapidly decreased with a half-life of less than 30 and 120 min for COX-1 and H-PGDS, respectively. In the presence of a proteasome inhibitor, COX-1 and H-PGDS proteins accumulated within 10 and 30 min, respectively, and concurrently appeared as the high-molecular-mass ubiquitinated proteins within 30 and 60 min, respectively, after an increase in the intracellular calcium level. The ubiquitination of these proteins was also observed when ADP, instead of a calcium ionophore, was used as an inducer to elevate the intracellular calcium level. When the entry of calcium ion into the cells was inhibited by ethylene glycol tetraacetic acid (EGTA), the ubiquitination of COX-1 and H-PGDS was clearly suppressed; and the addition of CaCl2 to the medium cleared the EGTA-mediated suppression of the ubiquitination. These results indicate that COX-1 and H-PGDS were rapidly ubiquitinated and degraded through the ubiquitin–proteasome system in response to the elevation of the intracellular calcium level. PMID:22049022

Yazaki, Misato; Kashiwagi, Kaori; Aritake, Kosuke; Urade, Yoshihiro; Fujimori, Ko

2012-01-01

184

Project Calcium  

SciTech Connect

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

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

1992-09-01

185

Rosuvastatin calcium  

Microsoft Academic Search

Rosuvastatin calcium (Crestor; AstraZeneca), the seventh drug in the statin class, was approved by the US FDA in August 2003 for the reduction of cholesterol levels in patients with hypercholesterolaemia. Billed as the most potent statin available, can it overcome initial setbacks and make a significant impact in the multi-billion-dollar market for cholesterol-lowering drugs?

Mark Thornton; Peter Kirkpatrick; Jeremy Quirk

2003-01-01

186

Regulation of Chloride Channels by Protein Kinase C in Normal and Cystic Fibrosis Airway Epithelia  

NASA Astrophysics Data System (ADS)

Apical membrane chloride channels control chloride secretion by airway epithelial cells. Defective regulation of these channels is a prominent characteristic of cystic fibrosis. In normal intact cells, activation of protein kinase C (PKC) by phorbol ester either stimulated or inhibited chloride secretion, depending on the physiological status of the cell. In cell-free membrane patches, PKC also had a dual effect: at a high calcium concentration, PKC inactivated chloride channels; at a low calcium concentration, PKC activated chloride channels. In cystic fibrosis cells, PKC-dependent channel inactivation was normal, but activation was defective. Thus it appears that PKC phosphorylates and regulates two different sites on the channel or on an associated membrane protein, one of which is defective in cystic fibrosis.

Li, Ming; McCann, John D.; Anderson, Matthew P.; Clancy, John P.; Liedtke, Carole M.; Nairn, Angus C.; Greengard, Paul; Welsh, Michael J.

1989-06-01

187

A dominant trifluoperazine resistance gene from Saccharomyces cerevisiae has homology with F0F1 ATP synthase and confers calcium-sensitive growth.  

PubMed Central

The antipsychotic drug trifluoperazine has been long considered a calmodulin inhibitor from in vitro studies but may function in vivo as a more general inhibitor by disturbing ion fluxes and altering the membrane potential. Resistance to trifluoperazine can arise in Saccharomyces cerevisiae cells by alterations in at least three distinct genetic loci. One locus, defined by a spontaneous dominant trifluoperazine resistance mutation (TFP1-408), was isolated and sequenced. The sequence of the TFP1-408 gene revealed a large open reading frame coding for a large protein of 1,031 amino acids with predicted hydrophobic transmembrane domains. A search of existing amino acid sequences revealed a significant homology with F0F1 ATP synthase. Mutant TFP1-408 cells did not grow efficiently in the presence of 50 mM CaCl2, whereas wild-type cells did. Wild-type cells became resistant to trifluoperazine in the presence of 50 mM CaCl2 or 50 mM MgCl2. Mutant cells showed a higher rate of calcium transport relative to wild-type cells. These data suggest that the TFP1 gene product codes for a transmembrane ATPase-like enzyme possibly involved in Ca2+ transport or in generating a transmembrane ion gradient between two cellular compartments. Images PMID:2905423

Shih, C K; Wagner, R; Feinstein, S; Kanik-Ennulat, C; Neff, N

1988-01-01

188

Mechanochemical destruction of Dechlorane Plus with calcium oxide.  

PubMed

Dechlorane Plus (DP) was co-ground with calcium oxide (CaO) powder in a planetary ball mill at room temperature. A mechanochemical reaction was induced, resulting in the decomposition of DP through dechlorination. The influences of both the charge ratio and content of CaO were investigated. The co-ground samples were characterized and analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, gas chromatography/mass spectrometry (GC/MS), and ion chromatography (IC). With the increase in grinding time, the remained DP decreased and finally was completely destroyed after 4h grinding time in the mixture with a CaO/DP ratio of 25:1 and a charge ratio of 36:1. At the same time, the water-soluble amount of chlorine increased correspondingly and reached 88.6%, demonstrating that dechlorination is the major degradation mechanism. The main degradation products in the final reaction were carbon and CaCl(2), beside the excess CaO. The first carbon structure appeared after grinding treatment was graphite, while the second was amorphous carbon. PMID:20728200

Zhang, Wang; Huang, Jun; Yu, Gang; Deng, Shubo; Zhu, Wanpeng

2010-09-01

189

Rapid screening of mineralization capacity of biomaterials by means of quantification of enzymatically deposited calcium phosphate.  

PubMed

The current study focused on the development of a rapid, straightforward quantification method based on the use of enzymatic decomposition of urea using urease to assess the mineralization capacity of a wide range of biomaterials for bone regeneration. Urea-containing mineralizing solutions (MSs) (containing: Na2HPO4, CaCl2, and NaCl at 37°C and pH 6.0) were used in the mineralization experiments. Urease was added to these solutions to induce enzymatic decomposition of urea resulting in increased pH and deposition of calcium phosphate. By optimizing the ionic and urease concentrations in these MSs, it was shown that the proposed system could mineralize titanium substrates with six different pretreatments, as opposed to normal simulated body fluid that mineralized only two of them. It was possible to rank the mineralization capacity of these substrates by measuring the amount of calcium deposited. Furthermore, the ranking of (i) various polymeric substrates and (ii) hydrogels with and without functionalization with calcium-binding bisphosphonate groups was also possible. These results confirm that the proposed testing system has a broad applicability in the field of biomaterials due to its inherent versatility and discriminative power. PMID:24650236

Nijhuis, Arnold W G; Takemoto, Shinji; Nejadnik, M Reza; Li, Yubao; Yang, Xia; Ossipov, Dmitri A; Hilborn, Jons; Mikos, Antonios G; Yoshinari, Masao; Jansen, John A; Leeuwenburgh, Sander C G

2014-10-01

190

Preparation of coagulant from red mud and semi-product of polyaluminum chloride for removal of phosphate from water  

Microsoft Academic Search

Traditionally, calcium aluminate, caustic soda, lime or aluminum slag was employed as alkali for basicity adjustment in the production of polyaluminum chloride (PACl). In this work, red mud (RM), a highly alkaline waste from alumina industry, was utilized instead of the traditional alkali. A composite coagulant (RMPACl) was prepared from RM and the semi-product of polyaluminum chloride (ACl). Important factors

Fan Ni; Xianjia Peng; Ying Zhao; Jinsong He; Yiran Li; Zhaokun Luan

2012-01-01

191

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

PubMed Central

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

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

2013-01-01

192

Chloride removal from vitrification offgas  

SciTech Connect

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

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

1995-06-01

193

Molecular Structure of Barium Chloride  

NSDL National Science Digital Library

Barium Chloride was the byproduct of the discovery of radium by Madame Curie. When refining radium, the final separation resulted in barium chloride and radium chloride. Electrophoresis of barium chloride produces small-scale amounts of barium atom. This can be used for obtaining barium for commercial uses. Applications of barium chloride include stimulating the heart and other muscles for medicinal purposes, and also for softening water. Other uses of barium chloride include the manufacturing of barium salts, as pesticide, pigments, boiler detergent, in purifying sugar, as mordant in dyeing and printing textiles, and in the manufacture of caustic soda, polymers, and stabilizers.

2002-08-15

194

Osmotic dehydration of apple slices using a sucrose/CaCl2 combination to control spoilage caused by Botrytis cinerea, Colletotrichum acutatum, and Penicillium expansum.  

PubMed

The efficacy of sucrose combined with CaCl2 during osmotic dehydration (OD) was tested for the control of Botrytis cinerea, Colletotrichum acutatum, and Penicillium expansum growth on lightly processed apple slices. The objective of this work was to determine whether the addition of CaCl2 in the osmotic solutions would limit the proliferation of fungal decay organisms. Slices were submitted to OD for 1 h at 25 degrees C in solutions containing 5 to 65% sucrose. Calcium chloride was added to a similar set of sucrose solutions at 0 to 8%. Control slices were made of untreated slices, and slices were processed in water. The mass ratio of the slices did not vary when fruit pieces were processed in solutions containing 5 to 65% sucrose. These slices showed a high susceptibility to spoilage compared to the control slices not submitted to OD: a significant twofold and 60% increase in decay area caused by B. cinerea and P. expansum, respectively, was observed when slices were processed in 50% sucrose/0% CaCl2; C. acutatum showed a significant 50% increase in decay area when slices were processed in 20% sucrose/0% CaCl2. Calcium uptake was significantly increased when slices were processed in CaCl2 solutions, and the highest Ca content was observed when processed in 8% CaCl2, reaching 40 times that of the control slices processed in water. Calcium-treated slices were less susceptible to spoilage by all three pathogens, and the most effective combination in reducing apple slice spoilage was 20 to 30% sucrose combined with 2% CaCl2. PMID:11563522

Chardonnet, C O; Sams, C E; Conway, W S; Mount, J R; Draughon, F A

2001-09-01

195

Calcium and osteoporosis  

Microsoft Academic Search

Calcium is an essential nutrient that is involved in most metabolic processes and the phosphate salts of which provide mechanical rigidity to the bones and teeth, where 99% of the body's calcium resides. The calcium in the skeleton has the additional role of acting as a reserve supply of calcium to meet the body's metabolic needs in states of calcium

B. E. Christopher Nordin

1997-01-01

196

Calcium Collage  

NSDL National Science Digital Library

In this activity (on pages 11-14 of PDF), learners cut out pictures from magazines of foods that help make bones strong and glue the pictures to a paper bone. The lesson plan includes information about various activities - including physical exercise as well as diet - that lead to healthy bones. It also includes a list of foods that provide calcium to strengthen bones, including dairy products, spinach, and tofu. The paper bones can be cut out of construction paper prior to the activity.

Omsi

2004-01-01

197

Evidence of changes in membrane pore characteristics due to filtration of dye bath liquors  

Microsoft Academic Search

This study was carried out to investigate the treatment of various salt solutions and synthetic dye bath liquors by nanofiltration using Nanomax-50 membrane in a stirred cell with 150 mL working volume. Donnan exclusion was compared by filtering salts with monovalent and divalent cations and anions. This was done by comparing three salts including sodium chloride (NaCl), calcium chloride (CaCl2)

P. Denyer; L. Shu; V. Jegatheesan

2007-01-01

198

SOURCE ASSESSMENT: POLYVINYL CHLORIDE  

EPA Science Inventory

This report summarizes data on air emissions from the polyvinyl chloride (PVC) industry. PVC is manufactured by 20 companies at 35 plants. Each plant uses one or more of four possible polymerization processes: (1) suspension polymerization, (2) emulsion polymerization, (3) bulk p...

199

Moxifloxacinium chloride monohydrate  

PubMed Central

The title compound {systematic name: 7-[(1S,6S)-8-aza-2-azonia­bicyclo­[4.3.0]non-8-yl]-1-cyclo­propyl-6-fluoro-8-meth­oxy-4-oxo-1,4-dihydro­quinoline-3-carb­oxy­lic acid chloride monohydrate}, C21H25FN3O4 +·Cl?·H2O, crystallizes with two moxi­floxa­cinium cations, two chloride ions and two uncoordinated water mol­ecules in the unit cell. The crystal structure has a pseudo-inversion center except for the chloride ions. In both moxi­floxa­cinium cations, the quinoline rings are approximately planar, the maximum atomic deviations being 0.107?(3) and 0.118?(3)?Å. The piperidine rings adopt a chair conformation while the pyrrolidine rings display a half-chair conformation. In the crystal, the carboxyl groups, the protonated piperidyl groups, the uncoordinated water mol­ecule and chloride anions participate in O—H?O, O—H?Cl and N—H?Cl hydrogen bonding; weak inter­molecular C—H?O and C—H?Cl hydrogen bonding is also present in the crystal structure. PMID:22058817

Qian, Jing-Jing; Gu, Jian-Ming; Shen, Jin; Hu, Xiu-Rong; Wu, Su-Xiang

2011-01-01

200

PHOTOOXIDATION OF ALLYL CHLORIDE  

EPA Science Inventory

The photooxidation of allyl chloride was studied by irradiation either in 100-L Teflon bags or in a 22.7-cu m Teflon smog chamber in the presence of added NOx. In the absence of added hydrocarbons, the reaction involves a Cl atom chain, which leads to a highly reactive system. A ...

201

The Involvement of the Mid1/Cch1/Yvc1 Calcium Channels in Aspergillus fumigatus Virulence  

PubMed Central

Aspergillus fumigatus is a major opportunistic pathogen and allergen of mammals. Calcium homeostasis and signaling is essential for numerous biological processes and also influences A. fumigatus pathogenicity. The presented study characterized the function of the A. fumigatus homologues of three Saccharomyces cerevisiae calcium channels, voltage-gated Cch1, stretch-activated Mid1 and vacuolar Yvc1. The A. fumigatus calcium channels cchA, midA and yvcA were regulated at transcriptional level by increased calcium levels. The YvcA::GFP fusion protein localized to the vacuoles. Both ?cchA and ?midA mutant strains showed reduced radial growth rate in nutrient-poor minimal media. Interestingly, this growth defect in the ?cchA strain was rescued by the exogenous addition of CaCl2. The ?cchA, ?midA, and ?cchA ?midA strains were also sensitive to the oxidative stress inducer, paraquat. Restriction of external Ca2+ through the addition of the Ca2+-chelator EGTA impacted upon the growth of the ?cchA and ?midA strains. All the A. fumigatus ?cchA, ?midA, and ?yvcA strains demonstrated attenuated virulence in a neutropenic murine model of invasive pulmonary aspergillosis. Infection with the parental strain resulted in a 100% mortality rate at 15 days post-infection, while the mortality rate of the ?cchA, ?midA, and ?yvcA strains after 15 days post-infection was only 25%. Collectively, this investigation strongly indicates that CchA, MidA, and YvcA play a role in A. fumigatus calcium homeostasis and virulence. PMID:25083783

de Castro, Patricia Alves; Chiaratto, Jessica; Winkelstroter, Lizziane K.; Bom, Vinicius Leite Pedro; Ramalho, Leandra Naira Zambelli; Goldman, Maria Helena S.; Brown, Neil Andrew; Goldman, Gustavo H.

2014-01-01

202

Calcium source (image)  

MedlinePLUS

... kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also effects the heart and circulatory system, as well as the secretion of essential hormones. There are many ways to supplement calcium, including a growing number of fortified foods.

203

Chloride ATPase Pumps in Epithelia  

Microsoft Academic Search

\\u000a Five widely documented mechanisms for chloride transport across biological membranes are known: anion-coupled antiport, Na+ and H(+)-coupled symport, Cl? channels and an electrochemical coupling process. These transport processes for chloride are either secondarily active or\\u000a are driven by the electrochemical gradient for chloride. Until recently, the evidence in favour of a primary active transport\\u000a mechanism for chloride has been inconclusive

George A. Gerencser

204

Impairment of ?1-adrenoceptor-mediated calcium influx in contralateral carotids following balloon injury: beneficial effect of superoxide anions.  

PubMed

There are many evidences indicating a compensatory mechanism in contralateral carotids following balloon injury. Previously it was observed ?1-adrenoceptor-mediated hyper-reactivity and impairment of calcium influx in contralateral carotids 4 days after injury. At a later stage, ?1-adrenoceptor-mediated contraction is similar to the control and we hypothesized that downstream signaling was normal. In the present study, we aimed to evaluate ?1-adrenoceptor-mediated calcium influx in contralateral carotids 15 days after balloon injury. Concentration-response curves for CaCl2 in presence of the ?1-adrenoceptor agonist (phenylephrine), measurement of the intracellular calcium transient and the levels of reactive oxygen species using fluorescent dyes were performed in control and contralateral carotids. Phenylephrine-induced intracellular calcium mobilization in contralateral carotids was not altered, while phenylephrine-induced calcium influx was reduced in the contralateral artery. Nitric oxide synthase inhibitors, L-NAME or L-NNA, restored this response, but nitrite and nitrate levels were decreased in contralateral carotids. Additionally, a rise in oxygen free radicals was observed in contralateral carotids. Furthermore, Tiron, a superoxide anion scavenger, restored ?1-adrenoceptor-mediated calcium influx in contralateral carotids to the control level. Similar results were observed with the selective potassium channels blockers 4-aminopyridine and charybdotoxin. In conclusion, data showed that balloon catheter injury resulted in increased superoxide anions levels, activation of potassium channels (Kv and BKCa), inhibition of calcium channels (Cav) and preservation of ?1-adrenoceptor-mediated contraction at a later stage after injury. PMID:24216248

Pereira, Aline C; Olivon, Vania C; Pernomian, Larissa; de Oliveira, Ana M

2014-01-15

205

Permeant Anions Control Gating of Calcium-dependent Chloride Channels  

Microsoft Academic Search

The effects of external anions (SCN?, NO3?, I?, Br?, F?, glutamate, and aspartate) on gating of Ca2+-dependent Cl? channels from rat parotid acinar cells were studied using the whole-cell configuration of the patch-clamp technique. Shifts in the reversal potential of the current induced by replacement of external Cl? with foreign anions, gave the following selectivity sequence based on permeability ratios

P. Perez-Cornejo; J. A. De Santiago; J. Arreola

2004-01-01

206

Electrochemical studies of calcium chloride-based molten salt systems  

SciTech Connect

Conductance and EMF studies of CaCl{sub 2}-based melts were performed in the temperature range 790--990 C. Conductivity data collected using magnesia tubes and capillaries showed deviations from the data recommended by the National Bureau of Standards. These deviations are attributed to the slow dissolution of magnesia by the CaCl{sub 2}-CaO melt. Conductivity data for molten CaCl{sub 2} using a pyrolytic boron nitride capillary were in reasonable agreement with the recommended data; however, undissolved CaO in CaCl{sub 2} may have caused blockage of the pyrolytic boron nitride capillary, resulting in fluctuations in the measured resistance. The utility of the AgCl/Ag reference electrode in CaCl{sub 2}-AgCl and CaCl{sub 2}-CaO-AgCl melts, using asbestos diaphragms and Vycor glass as reference half-cell membranes, was also investigated. Nernstian behavior was observed using both types of reference half-cell membranes in CaCl{sub 2}-AgCl melts. The AgCl/Ag reference electrode also exhibited Nernstian behavior in CaCl{sub 2}-CaO-AgCl melts using a Vycor reference half-cell membrane and a magnesia crucible. The use of CaCl{sub 2} as a solvent is of interest since it is used in plutonium metal purification, as well as various other commercial applications. 97 refs., 33 figs., 13 tabs.

Blanchard, T.P. Jr.

1992-12-01

207

Nephrocalcinosis in chloride depleted rats  

Microsoft Academic Search

The ultrastructural features of the nephrocalcinosis associated with chloride depletion in the rat are described. The extent of calcification appeared to depend on the degree of chloride restriction. Within 3 days of chloride deprivation electron-dense granules were deposited on the brush border of proximal tubules in a concentric manner. Coalescence of satellite deposits formed large, lobulated liths with laminations, which

K. Sarkar; G. Tolnai; D. Z. Levine

1973-01-01

208

Sodium Chloride (Catheter Flush) Injection  

MedlinePLUS

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

209

Effect of chloride ion concentration on the galvanic corrosion of ? phase brass by eccrine sweat.  

PubMed

Inductively coupled plasma mass spectrometry measurement of the relative concentration of sodium, chloride, calcium, and potassium ions in eccrine sweat deposits from 40 donors revealed positive correlations between chloride and sodium (? = 0.684, p < 0.01) and chloride and calcium ions (? = 0.91, p < 0.01). Correlations between ion concentration and the corrosion of ? phase brass by the donated sweat were investigated by visual grading of the degree of corrosion, by measuring the copper/zinc ratio using energy-dispersive X-ray spectroscopy, and from a measurement of the potential difference between corroded and uncorroded brass when a large potential was applied to the uncorroded brass. An increasing copper/zinc ratio (indicative of dezincification) was found to correlate positively to both chloride ion concentration and visual grading of corrosion, while visual grading gave correlations with potential difference measurements that were indicative of the preferential surface oxidation of zinc rather than copper. PMID:22329398

Meekins, Andrew; Bond, John W; Chaloner, Penelope

2012-07-01

210

Chloride-Induced Stress Corrosion Cracking of Powder Metallurgy Duplex Stainless Steels  

Microsoft Academic Search

The chloride-induced stress corrosion cracking (SCC) resistance of nitrogen-alloyed, powder metallurgically (P\\/M) produced and hot isostatically pressed (HIP) duplex stainless steels (DSS) was investigated and compared to the SCC resistance of two commercial wrought (forged) DSS. Constant-strain (deflection) SCC tests with four-point, loaded-bend specimens were performed in aerated 50 wt% calcium chloride solution at 100 C with pH = 6.5

A. Laitinen; H. Haenninen

1996-01-01

211

Acute and chronic effects of lithium chloride on physiological and psychological measures in normals  

Microsoft Academic Search

In the acute experiment six healthy volunteers were given orally two doses of lithium chloride, 16 and 32 mmol, and placebo sodium chloride 32 mmol in a double-blind standardized procedure, with a 1-week interval between treatments. Compared to sodium, lithium produced a decrease in subjective well-being, decrease of skin conductance fluctuations, and increase in plasma calcium concentrations. Dose-related effects were

I. G. Karniol; J. Dalton; M. H. Lader

1978-01-01

212

Fabrication of Flexible Porous Calcium-Deficient Apatite -Alginate Composite and Its Evaluation  

NASA Astrophysics Data System (ADS)

The calcium-deficient apatite (Ca9.36(HPO4)0.74(PO4)5.26(OH)1.26·nH2O (Ca/P ratio=1.56): DAp) - alginate (AG) composite was fabricated by the ice crystal sublimation technique. The starting whisker-like calcium-deficient apatite (w-DAp) powder with long-axis length of 62.6 ?m and short-axis length of 2.85 ?m was prepared by the homogeneous precipitation technique. After mixing the w-DAp with AG paste (DAp/AG ratio: 10), the mixture was flash frozen at a temperature between -5 and -196°C. The frozen materials were further lyophilized at -50°C for 24 h under reduced pressure and put into 1 mol-dm-3 CaCl2 solution at room temperature for 24 h The microscopic observation showed that the pore size of w-DAp-AG composite increased from ~20 to ~100 ?m with decreasing concentration of starting AG paste from 7.5 to 2.5 mass% and with decreasing freezing temperature from -196°C down to -5°C. The maximum porosity of w-DAp-AG composite, which was fabricated using 2.5 mass% AG at the freezing temperature of -5°C, attained 92.3%.

Tsukuda, Souichirou; Umeda, Tomohiro; Koda, Seiichiro; Itatani, Kiyoshi

2011-10-01

213

Poly (vinylsulfonic acid) assisted synthesis of aqueous solution stable vaterite calcium carbonate nanoparticles.  

PubMed

Calcium carbonate nanoparticles of the vaterite polymorph were synthesized by combining CaCl2 and Na2CO3 in the presence of poly (vinylsulfonic acid) (PVSA). By studying the important experimental parameters we found that controlling PVSA concentration, reaction temperature, and order of reagent addition the particle size, monodispersity, and surface charge can be controlled. By increasing PVSA concentration or by decreasing temperature CCNPs with an average size from ?150 to 500 nm could be produced. We believe the incorporation of PVSA into the reaction plays a dual role to (1) slow down the nucleation rate by sequestering calcium and to (2) stabilize the resulting CCNPs as the vaterite polymorph, preventing surface calcification or aggregation into microparticles. The obtained vaterite nanoparticles were found to maintain their crystal structure and surface charge after storage in aqueous buffer for at least 5 months. The aqueous stable vaterite nanoparticles could be a useful platform for the encapsulation of a large variety of biomolecules for drug delivery or as a sacrificial template toward capsule formation for biosensor applications. PMID:24461857

Nagaraja, Ashvin T; Pradhan, Sulolit; McShane, Michael J

2014-03-15

214

Highly conductive carbon nanotube matrix accelerates developmental chloride extrusion in central nervous system neurons by increased expression of chloride transporter KCC2.  

PubMed

Exceptional mechanical and electrical properties of carbon nanotubes (CNT) have attracted neuroscientists and neural tissue engineers aiming to develop novel devices that interface with nervous tissues. In the central nervous system (CNS), the perinatal chloride shift represents a dynamic change that forms the basis for physiological actions of ?-aminobutyric acid (GABA) as an inhibitory neurotransmitter, a process of fundamental relevance for normal functioning of the CNS. Low intra-neuronal chloride concentrations are maintained by a chloride-extruding transporter, potassium chloride cotransporter 2 (KCC2). KCC2's increasing developmental expression underlies the chloride shift. In neural injury, repressed KCC2 expression plays a co-contributory role by corrupting inhibitory neurotransmission. Mechanisms of Kcc2 up-regulation are thus pertinent because of their medical relevance, yet they remain elusive. Here, it is shown that primary CNS neurons originating from the cerebral cortex, cultured on highly-conductive few-walled-CNT (fwCNT) have a strikingly accelerated chloride shift caused by increased KCC2 expression. KCC2 upregulation is dependent on neuronal voltage-gated calcium channels (VGCC) and, furthermore, on calcium/calmodulin-dependent kinase II, which is linked to VGCC-mediated calcium-influx. It is also demonstrated that accelerated Kcc2 transcription in brain-slices prepared from genetically-engineered reporter mice, in which Kcc2 promoter drives luciferase, when the cerebral cortex of these mice is exposed to fwCNT-coated devices. Based on these findings, whether fwCNT can enhance neural engineering devices for the benefit of neural injury conditions associated with elevated neuronal intracellular chloride concentration-such as pain, epilepsy, traumatic neural injury and ischemia-can now be addressed. Taken together, our novel insights illustrate how fwCNTs can promote low neuronal chloride in individual neurons and thus inhibitory transmission in neural circuits. PMID:23229576

Liedtke, Wolfgang; Yeo, Michele; Zhang, Hongbo; Wang, Yiding; Gignac, Michelle; Miller, Sara; Berglund, Ken; Liu, Jie

2013-04-01

215

Chloride and Salinity  

NSDL National Science Digital Library

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

2011-07-15

216

Quartz crystal microbalance with dissipation monitoring and surface plasmon resonance studies of carboxymethyl cellulose adsorption onto regenerated cellulose surfaces.  

PubMed

Adsorption of anionic polyelectrolytes, sodium salts of carboxymethyl celluloses (CMCs) with different degrees of substitution (DS = 0.9 and 1.2), from aqueous electrolyte solutions onto regenerated cellulose surfaces was studied using quartz crystal microbalance with dissipation monitoring (QCM-D) and surface plasmon resonance (SPR) experiments. The influence of both calcium chloride (CaCl(2)) and sodium chloride (NaCl) on CMC adsorption was examined. The QCM-D results demonstrated that CaCl(2) (divalent cation) caused significantly greater CMC adsorption onto regenerated cellulose surfaces than NaCl (monovalent cation) at the same ionic strength. The CMC layers adsorbed onto regenerated cellulose surfaces from CaCl(2) solutions exhibited greater stability upon exposure to flowing water than layers adsorbed from NaCl solutions. Both QCM-D and SPR results showed that CMC adsorption onto regenerated cellulose surfaces from CaCl(2) solutions increased with increasing CaCl(2) concentration up to the solubility limit (10 mM). Voigt-based viscoelastic modeling of the QCM-D data indicated that the CMC layers adsorbed onto regenerated cellulose surfaces had shear viscosities of ?(f) ? 10(-3) N·s·m(-2) and elastic shear moduli of ?(f) ? 10(5) N·m(-2). Furthermore, the combination of SPR spectroscopy and QCM-D showed that the CMC layers contained 90-95% water. Adsorption isotherms for CMCs in CaCl(2) solutions were also obtained from QCM-D and were fit by Freundlich isotherms. This study demonstrated that CMC adsorption from CaCl(2) solutions is useful for the modification of cellulose surfaces. PMID:21699205

Liu, Zelin; Choi, Heejun; Gatenholm, Paul; Esker, Alan R

2011-07-19

217

Regulation of calcium influx by second messengers in rat mast cells  

Microsoft Academic Search

Biphasic increases in the free intracellular calcium concentration, consisting of a large initial transient followed by a sustained elevation, are frequently observed in non-excitable cells following stimulation. In rat peritoneal mast cells a cAMP- and Ca-activated chloride current can interact with IP3-dependent calcium influx to provide the sustained elevation of intracellular Ca concentration following transient IP3-induced release of calcium from

Reinhold Penner; Gary Matthews; Erwin Neher

1988-01-01

218

The arrhythmogenic current ITI in the absence of electrogenic sodium-calcium exchange in sheep cardiac Purkinje fibres.  

PubMed Central

Sheep cardiac Purkinje fibres were voltage clamped with a two-microelectrode technique. Under conditions that are known to elevate intracellular calcium (0 mM-external potassium), membrane currents were examined. In the above conditions, a brief depolarizing pulse leads to an oscillatory inward current (ITI) which peaks at about 300 ms after the repolarization. An after-contraction is also observed, the peak of which occurs about 80 ms after the peak of ITI. This result is in accord with the results of Kass, Lederer, Tsien & Weingart (1978a). We replaced external sodium with an isotonic CaCl2 solution to remove the sodium-calcium exchange mechanism as a possible current carrier for ITI. In the steady state under these conditions an oscillatory membrane current and after-contraction are seen following repolarization. This current was identified as ITI on the basis of its temporal relation to both the repolarization step and the after-contraction. In isotonic CaCl2, ITI has a reversal potential of -37 mV. Because of this fact ITI cannot be explained by an electrogenic sodium-calcium exchange mechanism alone. The reversal potential suggests that ITI arises from a channel which is permeable to both potassium and calcium. Fluctuations of membrane current and of tension were recorded in the steady state at different holding potentials. Power spectral analysis showed that the current fluctuations were at a minimum at a holding potential of -37 mV. Tension fluctuations were, however, relatively constant over the range of membrane potentials examined (-17 to -70 mV). The peak power of the current fluctuations occurred at about 1.5 Hz (at a holding potential of -70 mV). This peak shifted towards higher frequencies with increasing depolarization. A similar shift in frequency was observed for the tension fluctuations. Cross-correlations between membrane current and tension were calculated for various steady membrane potentials. This analysis shows that the current fluctuations are associated with the tension fluctuations, each with a principal period of about 0.5 s. This analysis also shows that at potentials more negative than the reversal potential of ITI, increasing tension is associated with increasing inward current and that the tension fluctuations follow current fluctuations by about 70 ms. At potentials positive to the reversal potential of ITI, increasing tension was associated with increasing outward current. This analysis therefore indicates that the fluctuations in membrane current reverse at a potential similar to the reversal potential of ITI.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3746687

Cannell, M B; Lederer, W J

1986-01-01

219

Extracellular calcium is involved in egg yolk-induced head-to-head agglutination of bull sperm.  

PubMed

Head-to-head agglutination of bull sperm occurs when semen is highly diluted in an egg yolk-citrate diluent without streptomycin. The objectives were to investigate causes of sperm agglutination and the underlying mechanism. Aliquots of bull semen were diluted in a base diluent (BD) supplemented with various test components and the percentage of agglutinated sperm (% AggSp) was quantified at 1, 5, 24, 48, and 72 h of incubation. When sperm were incubated at 22 °C, no agglutination was observed in BD for up to 72 h, whereas the % AggSp was 5.0, 41.7, 72.2, 91.1, and 92.8% in BD + 5% egg yolk (BD + EY) at 1, 5, 24, 48 and 72 h, respectively. However, no sperm agglutination was observed in BD + EY if incubation temperature was 37 °C. Addition of 5 or 10 mM ethylenebis (oxyethyleneni-trilo) tetra-acetic acid to BD + EY reduced the % AggSp from 95% to <5% at 72 h (P < 0.001), but addition of 5 mM CaCl(2) to BD failed to induce sperm agglutination in the absence of egg yolk, implicating calcium and other factors in egg yolk. Addition of the citrate-soluble fraction (CSF) of egg yolk to BD induced sperm agglutination similar to whole egg yolk, whereas water- and saline-soluble fractions of egg yolk were ineffective. The sperm-agglutinating efficacy of CSF (the % AggSp = 95% at 72 h) was reduced by dialysis (20%; P < 0.05), partially restored by addition of 5 mM CaCl2 (70%; P < 0.05), but the calcium effect was neutralized by addition of 5 mM ethylenebis (oxyethyleneni-trilo) tetra-acetic acid (1.7%; P < 0.05), again implicating calcium. Addition of 30 ?M of a protein kinase A inhibitor (H-89) to an agglutinating diluent failed to inhibit sperm agglutination, whereas addition of 2 mM of a cAMP analogue, dbcAMP, to a nonagglutinating diluent failed to induce sperm agglutination. Agglutination status had no effect on sperm plasma membrane/acrosome status and mitochondrial membrane potential. In conclusion, calcium and other component(s) in the CSF of egg yolk induced head-to-head agglutination of bull sperm in a time- and temperature-dependent manner. Although the mechanism of agglutination was not determined, the cAMP- protein kinase A signaling pathway was not involved. PMID:22925643

Yang, D H; McMillan, A G; Standley, N T; Shannon, P; Xu, Z Z

2012-10-15

220

Calcium transport in gill cells of Ucides cordatus, a mangrove crab living in variable salinity environments.  

PubMed

Crustaceans show discontinuous growth and have been used as a model system for studying cellular mechanisms of calcium transport, which is the main mineral found in their exoskeleton. Ucides cordatus, a mangrove crab, is naturally exposed to fluctuations in calcium and salinity. To study calcium transport in this species during isosmotic conditions, dissociated gill cells were marked with fluo-3 and intracellular Ca(2+) change was followed by adding extracellular Ca(2+) as CaCl2 (0, 0.1, 0.25, 0.50, 1.0 and 5mM), together with different inhibitors. For control gill cells, Ca(2+) transport followed Michaelis-Menten kinetics with Vmax=0.137±0.001 ?Ca(2+)i (?M×22.10(4)cells(-1)×180s(-1); N=4; r(2)=0.99); Km=0.989±0.027mM. The use of different inhibitors for gill cells showed that amiloride (Na(+)/Ca(2+) exchange inhibitor) inhibited 80% of Ca(2+) transport in gill cells (Vmax). KB-R, an inhibitor of Ca influx in vertebrates, similarly caused a decrease in Ca(2+) transport and verapamil (Ca(2+) channel inhibitor) had no effect on Ca(2+) transport, while nifedipine (another Ca(2+) channel inhibitor) caused a 20% decrease in Ca(2+) affinity compared to control values. Ouabain, on the other hand, caused no change in Ca(2+) transport, while vanadate increased the concentration of intracellular calcium through inhibition of Ca(2+) efflux probably through the plasma membrane Ca(2+)-ATPase. Results show that transport kinetics for Ca(2+) in these crabs under isosmotic conditions is lower compared to a hyper-regulator freshwater crab Dilocarcinus pagei studied earlier using fluorescent Ca(2+) probes. These kinds of studies will help understanding the comparative mechanisms underlying the evolution of Ca transport in crabs living in different environments. PMID:23867752

Leite, V P; Zanotto, F P

2013-10-01

221

Strength, porosity, and chloride resistance of mortar using the combination of two kinds of pozzolanic materials  

NASA Astrophysics Data System (ADS)

This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash (FA), ground rice husk-bark ash (RB), and ground bagasse ash (BA). Ordinary Portland cement (CT) was blended with a single pozzolan and two pozzolans. Strength, porosity, rapid chloride penetration, immersion, and corrosion tests were performed to characterize the mortar. Test results showed that the use of ternary blends of CT, FA, and RB or BA decreased the porosity of the mortar, as compared with binary blended mortar containing CT and RB or BA. The resistance to chloride penetration of the mortar improved substantially with partial replacement of CT with FA, RB, and BA. The use of ternary blends of CT, FA and RB or BA produced the mortar with good strength and resistance to chloride penetration. The resistance to chloride penetration was higher with an increase in the replacement level due to the reduced calcium hydroxide.

Rukzon, Sumrerng; Chindaprasirt, Prinya

2013-08-01

222

Comparison of differences between PWD/PhJ and C57BL/6J mice in calcium solution preferences and chorda tympani nerve responses.  

PubMed

We used the C57BL/6J (B6) and PWD/PhJ (PWD) mouse strains to investigate the controls of calcium intake. Relative to the B6 strain, the PWD strain had higher preferences in two-bottle choice tests for CaCl(2), calcium lactate (CaLa), MgCl(2), citric acid and quinine hydrochloride, but not for sucrose, KCl or NaCl. We also measured taste-evoked chorda tympani (CT) nerve activity in response to oral application of these compounds. Electrophysiological results paralleled the preference test results, with larger responses in PWD than in B6 mice for those compounds that were more highly preferred for the former strain. The strain differences were especially large for tonic, rather than phasic, chorda tympani activity. These data establish the PWD strain as a "calcium-preferring" strain and suggest that differences between B6 and PWD mice in taste transduction or a related peripheral event contributes to the differences between the strains in preferences for calcium solutions. PMID:21219921

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

2011-03-28

223

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

PubMed

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

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

2007-06-01

224

Modeling acid-gas generation from boiling chloride brines  

PubMed Central

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

2009-01-01

225

Molecular Structure of Ferric chloride  

NSDL National Science Digital Library

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

2002-08-27

226

Laboratory study on the high-temperature capture of HCl gas by dry-injection of calcium-based sorbents.  

PubMed

This is a laboratory study on the reduction of combustion-generated hydrochloric acid (HCl) emissions by in-furnace dry-injection of calcium-based sorbents. HCl is a hazardous gaseous pollutant emitted in significant quantities by municipal and hazardous waste incinerators, coal-fired power plants, and other industrial furnaces. Experiments were conducted in a laboratory furnace at gas temperatures of 600-1000 degrees C. HCl gas diluted with N2, and sorbent powders fluidized in a stream of air were introduced into the furnace concurrently. Chlorination of the sorbents occurred in the hot zone of the furnace at gas residence times approximately 1 s. The sorbents chosen for these experiments were calcium formate (CF), calcium magnesium acetate (CMA), calcium propionate (CP), calcium oxide (CX), and calcium carbonate (CC). Upon release of organic volatiles, sorbents calcine to CaO at approximately 700 degrees C, and react with the HCl according to the reaction CaO + 2HCl <=> CaCl2 + H2O. At the lowest temperature case examined herein, 600 degrees C, direct reaction of HCl with CaCO3 may also be expected. The effectiveness of the sorbents to capture HCl was interpreted using the "pore tree" mathematical model for heterogeneous diffusion reactions. Results show that the thin-walled, highly porous cenospheres formed from the pyrolysis and calcination of CF, CMA, and CP exhibited high relative calcium utilization at the upper temperatures of this study. Relative utilizations under these conditions reached 80%. The less costly low-porosity sorbents, calcium carbonate and calcium oxide also performed well. Calcium carbonate reached a relative utilization of 54% in the mid-temperature range, while the calcium oxide reached an 80% relative utilization at the lowest temperature examined. The data matched theoretical predictions of sorbent utilization using the mathematical model, with activation energy and pre-exponential factors for the calcination reaction of 17,000 K and 300,000 (g gas/cm2/s/atm gas), respectively. Thus, the kinetics of the calcination reaction were found to be much faster (approximately 500 times) than those of the sulfation reaction examined previously in this laboratory. PMID:11219704

Shemwell, B; Levendis, Y A; Simons, G A

2001-01-01

227

Comparing polyaluminum chloride and ferric chloride for antimony removal  

Microsoft Academic Search

Antimony has been one of the contaminants required to be regulated, however, only limited information has been collected to date regarding antimony removal by polyaluminium chloride (PACl) and ferric chloride (FC). Accordingly, the possible use of coagulation by PACl or FC for antimony removal was investigated. Jar tests were used to determine the effects of solution pH, coagulant dosage, and

Meea Kang; Tasuku Kamei; Yasumoto Magara

2003-01-01

228

Studies in the development of nateglinide loaded calcium alginate and chitosan coated calcium alginate beads.  

PubMed

Nateglinide loaded alginate-chitosan beads were prepared by ionic gelation method for controlling the drug release by using various combinations of chitosan and Ca2+ as cation and alginate as anion. IR spectrometry, scanning electron microscopy, differential scanning calorimetry and X-ray powder diffractometry were used to investigate the physicochemical characteristics of the drug in the bead formulations. The calcium content in beads was determined by atomic absorption spectroscopy. The swelling ability of the beads in different media (pH 1.2, 4.5, 6.8) has been found to be dependent on the presence of polyelectrolyte complex of the beads and the pH of the media. The ability to release the Nateglinide was examined as a function of chitosan and calcium chloride content in the gelation medium. It is evident that the rate of drug release and its kinetics could be controlled by changing the chitosan and the calcium chloride concentrations. Calcium alginate beads released more than 95% of drug with in 8 h; whereas coated beads sustained the drug release and released only 75-80% of drug. The drug release mechanism analyzed indicates that the release follows either "anomalous transport" or "case-II transport". PMID:18670106

Basu, Sanat Kumar; Rajendran, Adhiyaman

2008-08-01

229

Dilute Solution Properties of Poly(dimethyldiallylammonium chloride) in Aqueous Sodium Chloride Solutions  

E-print Network

Dilute Solution Properties of Poly(dimethyldiallylammonium chloride) in Aqueous Sodium Chloride fractions in sodium chloride solutions by viscosity, size-exclusionchromatography, and light(dimethyldial1ylammonium chloride) (PDMDAAC)were prepared by preparative size-exclusion chromatography

Dubin, Paul D.

230

Molecular Structure of Picryl chloride  

NSDL National Science Digital Library

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

2002-09-20

231

Dissolution of various calcium fluoride preparations in inorganic solutions and in stimulated human saliva.  

PubMed

The aim of the present study was to examine the dissolution of various preparations of calcium fluoride in inorganic solutions and in human saliva. Calcium fluoride was prepared by mixing either 0.25 or 0.02 mol/l calcium chloride with 0.5 or 0.04 mol/l sodium fluoride. After preparation, the salts were washed in 1 mmol/l calcium chloride solution and in distilled water. A commercial product, calcium fluoride Suprapur (Merck), was used for comparison. The solubility of the salts was examined in distilled water, in a 2-mmol/l sodium phosphate solution, and in whole human saliva, produced by chewing paraffin. It was found that the calcium fluoride ion product after suspension for 1-3 h in distilled water ranged closely around 10(-10.7) for all salts. In the phosphate solution, the commercial product dissolved slowly, the ratio between dissolved fluoride and calcium ranged from 4 to 7, in buffered solutions approaching 2. The supernatant was not saturated by the salt. Our two calcium fluoride salts dissolved quickly and made the phosphate-containing solutions supersaturated with respect to fluorapatite, leading to fluorapatite formation, and because of compensating calcium fluoride dissolution, this led to increasing fluoride concentrations in saliva of up to around 85-95 ppm. The results of this study indicate that calcium fluoride of less than Suprapur standard may dissolve quickly in saliva, unless the dissolution is retarded by a physical barrier, like a forming pellicle. PMID:7850849

Larsen, M J; Ravnholt, G

1994-01-01

232

Measurement of ionic calcium, pH, and soluble divalent cations in milk at high temperature.  

PubMed

Dialysis and ultrafiltration were investigated as methods for measuring pH and ionic calcium and partitioning of divalent cations of milk at high temperatures. It was found that ionic calcium, pH, and total soluble divalent cations decreased as temperature increased between 20 and 80 degrees C in both dialysates and ultrafiltration permeates. Between 90 and 110 degrees C, ionic calcium and pH in dialysates continued to decrease as temperature increased, and the relationship between ionic calcium and temperature was linear. The permeabilities of hydrogen and calcium ions through the dialysis tubing were not changed after the tubing was sterilized for 1h at 120 degrees C. There were no significant differences in pH and ionic calcium between dialysates from raw milk and those from a range of heat-treated milks. The effects of calcium chloride addition on pH and ionic calcium were measured in milk at 20 degrees C and in dialysates collected at 110 degrees C. Heat coagulation at 110 degrees C occurred with addition of calcium chloride at 5.4mM, where pH and ionic calcium of the dialysate were 6.00 and 0.43mM, respectively. Corresponding values at 20 degrees C were pH 6.66 and 2.10mM. PMID:20105523

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

2010-02-01

233

Calcium carbonate overdose  

MedlinePLUS

... is an ingredient that is commonly found in antacids (for heartburn) and some dietary supplements. Calcium carbonate ... Products containing calcium carbonate, including Certain antacids ... mineral supplements Note: This list may not be all-inclusive.

234

Calcium absorption and achlorhydria  

Microsoft Academic Search

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

Robert R. Recker

1985-01-01

235

Calcium and Mitosis  

NASA Technical Reports Server (NTRS)

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.

Hepler, P.

1983-01-01

236

Hyperuricosuric calcium oxalate nephrolithiasis  

Microsoft Academic Search

Many investigators have observed that renal calcium stones may be associated with uric acid disorders. Prien and Prien [1] noted that patients with gout who had stone disease frequently passed stones which contained or were composed of calcium oxalate. Gutman [2] also observed a high frequency of calcium oxalate stones in patients who had gout; and he called attention to

Fredric L Coe

1978-01-01

237

Magnesium Chloride As A Road Deicer: A Critical Review  

E-print Network

Problem Statement: During the winter of 2000-2001 it was observed that scaling of concrete surfaces increased approximately 10 times from that of the previous 9 winters in the Idaho Falls Regional Area. A review of concrete making materials from all producers, specifically, cement, sand, gravel, water, and admixtures, revealed that all materials came from the same sources as in previous years, so the logical conclusion is that none of these ingredients was the root cause of the very visible and costly problem. Scaling, as defined by the American Concrete Institute (ACI 302) and the National Ready Mixed Concrete Association in their series of “Concrete In Practice, ” “ is the local flaking or peeling of a finished surface of hardened concrete as a result of freezing and thawing.” A literature review of published scientific papers, principally from university researchers and experienced concrete consultants, reveals that chloride containing deicing materials such as calcium chloride, potassium chloride, and sodium chloride, can exacerbate a scaling problem as concrete goes through freeze-thaw cycles. This is particularly the case if the concrete is relatively new (less than 2 years old). Similar to water expanding in an ice tray, freezing water in saturated concrete exerts tremendous expansive force which consequently leads to the surface of the concrete scaling off if the concrete, especially the surface, is not adequately protected with entrained air. Entrained air provides spaces

G. Snow

238

Polar Calcium Flux in Sunflower Hypocotyl Segments : II. The Effect of Segment Orientation, Growth, and Respiration.  

PubMed

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

de Guzman, C C; Dela Fuente, R K

1986-06-01

239

Calcium Signaling in Live Cells on Elastic Gels under Mechanical Vibration at Subcellular Levels  

PubMed Central

A new device was designed to generate a localized mechanical vibration of flexible gels where human umbilical vein endothelial cells (HUVECs) were cultured to mechanically stimulate these cells at subcellular locations. A Fluorescence Resonance Energy Transfer (FRET)-based calcium biosensor (an improved Cameleon) was used to monitor the spatiotemporal distribution of intracellular calcium concentrations in the cells upon this mechanical stimulation. A clear increase in intracellular calcium concentrations over the whole cell body (global) can be observed in the majority of cells under mechanical stimulation. The chelation of extracellular calcium with EGTA or the blockage of stretch-activated calcium channels on the plasma membrane with streptomycin or gadolinium chloride significantly inhibited the calcium responses upon mechanical stimulation. Thapsigargin, an endoplasmic reticulum (ER) calcium pump inhibitor, or U73122, a phospholipase C (PLC) inhibitor, resulted in mainly local calcium responses occurring at regions close to the stimulation site. The disruption of actin filaments with cytochalasin D or inhibition of actomyosin contractility with ML-7 also inhibited the global calcium responses. Therefore, the global calcium response in HUVEC depends on the influx of calcium through membrane stretch-activated channels, followed by the release of inositol trisphosphate (IP3) via PLC activation to trigger the ER calcium release. Our newly developed mechanical stimulation device can also provide a powerful tool for the study of molecular mechanism by which cells perceive the mechanical cues at subcellular levels. PMID:22053183

Nishitani, Wagner Shin; Saif, Taher A.; Wang, Yingxiao

2011-01-01

240

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

SciTech Connect

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

Papadakis, V.G.

2000-02-01

241

Potassium leaching in undisturbed soil cores following surface applications of gypsum  

Microsoft Academic Search

Displacement studies on leaching of potassium (K+) were conducted under unsaturated steady state flow conditions in nine undisturbed soil columns (15.5 cm in diameter and\\u000a 25 cm long). Pulses of K+ applied to columns of undisturbed soil were leached with distilled water or calcium chloride (CaCl2) at a rate of 18 mm h?1. The movement of K+ in gypsum treated soil leached with distilled

M. Jalali; D. L. Rowell

2009-01-01

242

Contribution of calcium oxalate to soil-exchangeable calcium  

USGS Publications Warehouse

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

Dauer, Jenny M.; Perakis, Steven S.

2013-01-01

243

Actin assembly in electropermeabilized neutrophils: role of intracellular calcium  

PubMed Central

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

1990-01-01

244

Original article Availability of calcium from skim milk, calcium sulfate  

E-print Network

Original article Availability of calcium from skim milk, calcium sulfate and calcium carbonate that the calcium in milk was more efficiently used than that from any other source. Carbonate, gluconate, citrate; accepted 19 November 1999) Abstract --Dairy products provide abundant, accessible calcium for humans, while

Paris-Sud XI, Université de

245

Calcium is incorporated into the calcium carbonate matrix of otoliths  

E-print Network

118 Calcium is incorporated into the calcium carbonate matrix of otoliths and into the calcium). In addition to calcium, trace elements, such as strontium, are also incorporated into the calcified components valence) allow strontium ions to act as replace- ments for calcium during the pro- cess of calcification

246

The role of extracellular calcium in pregnancy-induced attenuation of phenylephrine contraction in rat aorta with functional endothelium.  

PubMed

The effect of pregnancy on the supply of calcium ions for the contractile responses of rat aortic rings to phenylephrine was investigated. The contractility of intact aortic rings from pregnant rats, compared with that of similar rings from non-pregnant rats, to phenylephrine and potassium chloride was significantly decreased. Contractions of rings from non-pregnant rats, pretreated with phenylephrine or potassium chloride, in response to calcium chloride were greater than those of similarly treated rings from pregnant rats. When the concentration of calcium chloride in the medium bathing the rings was reduced to 0.8 mmol.l-1, the contractile response to phenylephrine was significantly (P < 0.005) inhibited in rings from both pregnant and non-pregnant rats but to a greater extent in rings from non-pregnant rats. Contractions of aortic rings from pregnant rats in response to phenylephrine in calcium-free medium were similar to those of rings from non-pregnant rats, suggesting equal dependence on calcium from intracellular stores. The results suggest that pregnancy decreased the response to calcium influx into the aortic smooth muscle cells through both receptor- and voltage-operated calcium entry pathways. Since de-endothelialization reversed the pregnancy-induced diminished contraction to phenylephrine, it is likely that pregnancy interfered with contractions induced by activation of receptors with phenylephrine through enhanced production of endothelium-derived relaxing factor(s). PMID:8014259

Ezimokhai, M; Aloamaka, C P; Cherian, T; Morrison, J

1994-01-01

247

Chloride channel blockade relaxes airway smooth muscle and potentiates relaxation by ?-agonists.  

PubMed

Severe bronchospasm refractory to ?-agonists continues to cause significant morbidity and mortality in asthmatic patients. We questioned whether chloride channels/transporters are novel targets for the relaxation of airway smooth muscle (ASM). We have screened a library of compounds, derivatives of anthranilic and indanyloxyacetic acid, that were originally developed to antagonize chloride channels in the kidney. We hypothesized that members of this library would be novel calcium-activated chloride channel blockers for the airway. The initial screen of this compound library identified 4 of 20 compounds that relaxed a tetraethylammonium chloride-induced contraction in guinea pig tracheal rings. The two most effective compounds, compounds 1 and 13, were further studied for their potential to either prevent the initiation of or relax the maintenance phase of an acetylcholine (ACh)-induced contraction or to potentiate ?-agonist-mediated relaxation. Both relaxed an established ACh-induced contraction in human and guinea pig ex vivo ASM. In contrast, the prevention of an ACh-induced contraction required copretreatment with the sodium-potassium-chloride cotransporter blocker bumetanide. The combination of compound 13 and bumetanide also potentiated relaxation by the ?-agonist isoproterenol in guinea pig tracheal rings. Compounds 1 and 13 hyperpolarized the plasma cell membrane of human ASM cells and blocked spontaneous transient inward currents, a measure of chloride currents in these cells. These functional and electrophysiological data suggest that modulating ASM chloride flux is a novel therapeutic target in asthma and other bronchoconstrictive diseases. PMID:24879056

Danielsson, Jennifer; Yim, Peter; Rinderspacher, Alison; Fu, Xiao Wen; Zhang, Yi; Landry, Donald W; Emala, Charles W

2014-08-01

248

CHLORIDE WASHER PERFORMACE TESTING  

SciTech Connect

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

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

2007-11-30

249

Biomimetic synthesis of calcium-deficient hydroxyapatite in a natural hydrogel  

Microsoft Academic Search

A novel composite material consisting of calcium-deficient hydroxyapatite (CdHAP) biomimetically deposited in a bacterial cellulose hydrogel was synthesized and characterized. Cellulose produced by Gluconacetobacter hansenii was purified and sequentially incubated in solutions of calcium chloride followed by sodium phosphate dibasic. A substantial amount of apatite (50–90% of total dry weight) was homogeneously incorporated throughout the hydrogel after this treatment. X-ray

Stacy A. Hutchens; Roberto S. Benson; Barbara R. Evans; Hugh M. O’Neill; Claudia J. Rawn

2006-01-01

250

Expression and modulation of voltage-gated calcium channels after RNA injection in Xenopus oocytes.  

PubMed

Calcium ions flow into cells through several distinct classes of voltage-dependent calcium-selective channels. Such fluxes play important roles in electrical signaling at the cell membrane and in chemical signaling within cells. Further information about calcium channels was obtained by injecting RNA isolated from rat brain, heart and skeletal muscle into Xenopus oocytes. Macroscopic currents through voltage-operated calcium channels were resolved when the endogenous calcium-dependent chloride current was blocked by replacing external calcium with barium and chloride with methanesulfonate. The resulting barium current was insensitive to tetrodotoxin but was completely blocked by cadmium or cobalt. With both heart and brain RNA at least two distinct types of calcium ion conductance were found, distinguishable by their time course and inactivation properties. In oocytes injected with heart RNA, the slowly inactivating component was selectively blocked by the calcium-channel antagonist nifedipine. Barium ion currents induced by heart RNA were modulated by isoproterenol, cyclic adenosine monophosphate, and acetylcholine. PMID:2418503

Dascal, N; Snutch, T P; Lübbert, H; Davidson, N; Lester, H A

1986-03-01

251

Buffering effects of calcium salts in kimchi: lowering acidity, elevating lactic acid bacterial population and dextransucrase activity.  

PubMed

This study investigates the buffering effects of calcium salts in kimchi on total acidity, microbial population, and dextransucrase activity. Calcium chloride or calcium carbonate was added in dongchimi-kimchi, a watery-radish kimchi, and their effects on various biochemical attributes were analyzed. The addition of 0.1% calcium chloride produced a milder decrease in the pH after 24 days of incubation, which allowed the lactic acid bacteria to survive longer than in the control. In particular, the heterofermentative Leuconostoc genus population was 10-fold higher than that in the control. When sucrose and maltose were also added along with the calcium salts, the dextransucrase activity in the kimchi was elevated and a higher concentration of isomaltooligosaccharides was synthesized when compared with the control. Calcium chloride was determined as a better activator compound of dextransucrase than calcium carbonate, probably because of its higher solubility. Therefore, the results of this study confirm the ability of the proposed approach to modulate the kimchi fermentation process and possibly enhance the quality of kimchi based on the addition of dietary calcium salts. PMID:20075632

Chae, Seo Eun; Moon, Jin Seok; Jung, Jee Yun; Kim, Ji-Sun; Eom, Hyun-Ju; Kim, So-Young; Yoon, Hyang Sik; Han, Nam Soo

2009-12-01

252

Micro Determination of Calcium  

Microsoft Academic Search

Hildebrand and Reilly1 have recently described a complexometric titration method for the determination of calcium: the indicator used, `Calcon', is superior to `Solochrome' black in that calcium can be determined independently of magnesium, and, unlike the murexide method, a sharp end-point is obtained. All three methods employ ethylenediamine tetraacetic acid. The purpose of the present communication is to direct attention

A. B. Gilbert

1959-01-01

253

Evidence for intestinal chloride secretion.  

PubMed

Intestinal fluid secretion is pivotal in the creation of an ideal environment for effective enzymatic digestion, nutrient absorption and stool movement. Since fluid cannot be actively secreted into the gut, this process is dependent on an osmotic gradient, which is mainly created by chloride transport by the enterocyte. A pathological dysbalance between fluid secretion and absorption leads to obstruction or potentially fatal diarrhoea. This article reviews the widely accepted model of intestinal chloride secretion with an emphasis on the molecular players involved in this tightly regulated process. PMID:20233891

Murek, Michael; Kopic, Sascha; Geibel, John

2010-04-01

254

Influence of water hardness and sulfate on the acute toxicity of chloride to sensitive freshwater invertebrates.  

PubMed

Total dissolved solids (TDS) represent the sum of all common ions (e.g., Na, K, Ca, Mg, chloride, sulfate, and bicarbonate) in freshwater. Currently, no federal water quality criteria exist for the protection of aquatic life for TDS, but because the constituents that constitute TDS are variable, the development of aquatic life criteria for specific ions is more practical than development of aquatic life criteria for TDS. Chloride is one such ion for which aquatic life criteria exist; however, the current aquatic life criteria dataset for chloride is more than 20 years old. Therefore, additional toxicity tests were conducted in the current study to confirm the acute toxicity of chloride to several potentially sensitive invertebrates: water flea (Ceriodaphnia dubia), fingernail clams (Sphaerium simile and Musculium transversum), snail (Gyraulus parvus), and worm (Tubifex tubifex), and determine the extent to which hardness and sulfate modify chloride toxicity. The results indicated a significant ameliorating effect of water hardness (calcium and magnesium) on chloride toxicity for all species tested except the snail; for example, the 48-h chloride median lethal concentration (LC50) for C. dubia at 50?mg/L hardness (977?mg Cl(-) /L) was half that at 800?mg/L hardness (1,836?mg Cl(-) /L). Conversely, sulfate over the range of 25 to 600?mg/L exerted a negligible effect on chloride toxicity to C. dubia. Rank order of LC50 values for chloride at a given water hardness was in the order (lowest to highest): S. simile?

Soucek, David J; Linton, Tyler K; Tarr, Christopher D; Dickinson, Amy; Wickramanayake, Nilesh; Delos, Charles G; Cruz, Luis A

2011-04-01

255

Chloride thresholds in marine concrete  

Microsoft Academic Search

This paper reports results from an ongoing study of the performance of fly ash concrete in marine exposure. Reinforced concrete specimens exposed to tidal conditions were retrieved at ages ranging from 1 to 4 years. Steel reinforcement mass losses are compared with chloride contents at the location of the bar for concrete specimens of various strength grades and with a

Michael Thomas

1996-01-01

256

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

USGS Publications Warehouse

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

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

1999-01-01

257

Sequential CaCl 2, polyethylene glycol precipitation for RNase-free plasmid DNA isolation  

Microsoft Academic Search

Functional genomics is facilitated by the ability to express genes in heterologous systems. In some cases function can be assayed by generation of in vitro transcripts of the unknown genes and expressing those transcripts in various expression systems. Plasmids bearing phage promoters are used to generate in vitro transcripts. Therefore, it is important to ensure that the template plasmid DNA

Marie-Laure Sauer; Brett Kollars; Ryan Geraets; Fedora Sutton

2008-01-01

258

Longitudinal changes during the development of hypertension in rats fed excess chloride and sodium.  

PubMed

The effects of supplemental NaCl, KCl, and Na acetate on the blood pressure of weanling rats fed semipurified diets and diets based on naturally high salt products, like cottage cheese, were examined in two studies. Within 2 weeks of initiation of dietary treatments, rats fed supplemental chloride had elevated blood pressure and lowered plasma renin activity, which persisted throughout the 8-week study. The effect of supplemental sodium on blood pressure was not significant until after 6 weeks of dietary treatment. The initial increase in blood pressure preceded the slowed growth observed in rats fed excess chloride or sodium. Urinary volume and urinary excretion of calcium, magnesium, phosphorus, sodium, and chloride were increased when supplemental chloride or sodium was fed, but tissue electrolyte and plasma atrial natriuretic peptide concentrations remained constant. Two changes preceded the rise in blood pressure: rats fed supplemental chloride had enlarged kidneys, and those fed supplemental sodium had elevated hematocrits, suggesting a transient shift among fluid compartments, after only 6 days of treatment. These data suggest that the hypertension induced by ingestion of supplemental (14.6 mg CI/g of diet) chloride is mediated by changes in renal function. Ingestion of excess sodium depressed bone magnesium concentrations in Study 1 and after 24 days in Study 2; the impact of this "relative" magnesium depletion on blood pressure deserves further study. PMID:8516350

Greger, J L; Tseng, E

1993-07-01

259

21 CFR 184.1138 - Ammonium chloride.  

...sodium chloride and an ammonium salt in solution. The less soluble sodium salt...Ammonium chloride is crystallized from the solution. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981),...

2014-04-01

260

29 CFR 1910.1017 - Vinyl chloride.  

Code of Federal Regulations, 2012 CFR

...following hazards are to be addressed: Cancer; central nervous system effects; liver... DANGER VINYL CHLORIDE MAY CAUSE CANCER AUTHORIZED PERSONNEL ONLY (ii... DANGER VINYL CHLORIDE MAY CAUSE CANCER WEAR RESPIRATORY PROTECTION AND...

2012-07-01

261

29 CFR 1910.1017 - Vinyl chloride.  

...following hazards are to be addressed: Cancer; central nervous system effects; liver... DANGER VINYL CHLORIDE MAY CAUSE CANCER AUTHORIZED PERSONNEL ONLY (ii... DANGER VINYL CHLORIDE MAY CAUSE CANCER WEAR RESPIRATORY PROTECTION AND...

2014-07-01

262

29 CFR 1910.1017 - Vinyl chloride.  

Code of Federal Regulations, 2013 CFR

...following hazards are to be addressed: Cancer; central nervous system effects; liver... DANGER VINYL CHLORIDE MAY CAUSE CANCER AUTHORIZED PERSONNEL ONLY (ii... DANGER VINYL CHLORIDE MAY CAUSE CANCER WEAR RESPIRATORY PROTECTION AND...

2013-07-01

263

21 CFR 184.1297 - Ferric chloride.  

Code of Federal Regulations, 2013 CFR

...occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron...Reg. No. 10025-77-1) is readily formed when ferric chloride is exposed to moisture...Prior sanctions for this ingredient different from the uses established in this...

2013-04-01

264

21 CFR 184.1297 - Ferric chloride.  

Code of Federal Regulations, 2012 CFR

...occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron...Reg. No. 10025-77-1) is readily formed when ferric chloride is exposed to moisture...Prior sanctions for this ingredient different from the uses established in this...

2012-04-01

265

21 CFR 184.1297 - Ferric chloride.  

Code of Federal Regulations, 2011 CFR

...occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron...Reg. No. 10025-77-1) is readily formed when ferric chloride is exposed to moisture...Prior sanctions for this ingredient different from the uses established in this...

2011-04-01

266

The sealing ability of MTA apical plugs exposed to a phosphate-buffered saline  

PubMed Central

Objective The aim of this study was to evaluate the influence of exposure of the mineral trioxide aggregate (MTA) - with and without calcium chloride (CaCl2) - to phosphate-buffered saline (PBS) on the apical microleakage using a glucose leakage system. Material and Methods Sixty root segments were randomly divided into 4 experimental groups (n=15). After resecting the apical segments and enlarging the canals with Gates-Glidden drills, the apical cavities were filled with MTA with or without CaCl2 and the root canals were dressed with a moistened cotton pellet or PBS, as follows: 1) MTA/cotton pellet; 2) MTA/PBS; 3) MTA+10%CaCl2/cotton pellet; 4) MTA+10%CaCl2/PBS. All root segments were introduced in floral foams moistened with PBS. After 2 months, all root segments were prepared to evaluate the glucose leakage along the apical plugs. The amount of glucose leakage was measured following an enzymatic reaction and quantified by a spectrophotometer. Four roots were used as controls. The data were analyzed using Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results There were no differences between groups 1 and 2 (p>0.05), and 3 and 4 (p>0.05). The addition of CaCl2 to the MTA significantly decreased its sealing ability (p<0.05). Conclusion The interaction with PBS did not improve the MTA sealing ability. The addition of CaCl2 to the MTA negatively influenced the apical seal. PMID:24037073

de ALMEIDA, Josiane; ALVES, Ana Maria Hecke; de MELO, Roberto Ferreira; FELIPPE, Mara Cristina Santos; BORTOLUZZI, Eduardo Antunes; TEIXEIRA, Cleonice da Silveira; FELIPPE, Wilson Tadeu

2013-01-01

267

Ecological risk assessment of on-site soil washing with iron(III) chloride in cadmium-contaminated paddy field.  

PubMed

On-site soil washing with iron(III) chloride reduces Cd levels in soil, and thus the human health risks caused by Cd in food. However, it may threaten aquatic organisms when soil washing effluent is discharged to open aquatic systems. Therefore, we conducted trial-scale on-site soil washing and ecological risk assessment in Nagano and Niigata prefectures, Japan. The ecological effect of effluent water was investigated by two methods. The first was bioassay using standard aquatic test organisms. Twice-diluted effluent water from the Nagano site and the original effluent water from the Niigata site had no significant effects on green algae, water flea, caddisfly, and fish. The safe dilution rates were estimated as 20 times and 10 times for the Nagano and Niigata sites, respectively, considering an assessment factor of 10. The second method was probabilistic effect analysis using chemical analysis and the species sensitivity distribution concept. The mixture effects of CaCl(2), Al, Zn, and Mn were considered by applying a response additive model. The safe dilution rates, assessed for a potentially affected fraction of species of 5%, were 7.1 times and 23.6 times for the Nagano and Niigata sites, respectively. The actual dilution rates of effluent water by river water at the Nagano and Niigata sites were 2200-67,000 times and 1300-110,000 times, respectively. These are much larger than the safe dilution rates derived from the two approaches. Consequently, the ecological risk to aquatic organisms of soil washing is evaluated as being below the concern level. PMID:22377402

Nagai, Takashi; Horio, Takeshi; Yokoyama, Atsushi; Kamiya, Takashi; Takano, Hiroyuki; Makino, Tomoyuki

2012-06-01

268

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

USGS Publications Warehouse

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

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

1979-01-01

269

Orthophosphate Removal from a Synthetic Wastewater Using Lime, Alum, and Ferric Chloride  

Microsoft Academic Search

Lime, alum, and ferric chloride were evaluated using a series of jar tests to determine their effectiveness in Orthophosphate precipitation from synthetic wastewaters. Calcium phosphate precipitation was most efficient at pH 11.0 and a total carbonate to phosphorus, CT:P, molar ratio of 15.0. For these conditions, a residual total Orthophosphate concentration of 0.12 mg\\/L-P was observed. The Mg:P molar ratio

Lynn Sisk; Larry Benefield; Bruce Reed

1987-01-01

270

Microbial reductive dehalogenation of vinyl chloride  

DOEpatents

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

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

2011-11-22

271

Effects of calcium on biocontrol activity of yeast antagonists against the postharvest fungal pathogen Rhizopus stolonifer  

Microsoft Academic Search

Calcium chloride (2% w\\/v) significantly inhibited the growth of the pathogen Rhizopus stolonifer, but did not affect the colony-forming unit (CFU) of yeasts Candida guilliermondii and Pichia membranefaciens in potato dextrose broth. The concentration of yeast suspension influenced spore germination and germ tube growth of R. stolonifer in vitro, as well as disease incidence and lesion development in fruits. There

S. P. Tian; Q. Fan; Y. Xu; A. L. Jiang

2002-01-01

272

A study on high strength concrete prepared with large volumes of low calcium fly ash  

Microsoft Academic Search

This paper presents the results of a laboratory study on high strength concrete prepared with large volumes of low calcium fly ash. The parameters studied included compressive strength, heat of hydration, chloride diffusivity, degree of hydration, and pore structures of fly ash\\/cement concrete and corresponding pastes. The experimental results showed that concrete with a 28-day compressive strength of 80 MPa

C. S. Poon; L. Lam; Y. L. Wong

2000-01-01

273

21 CFR 184.1297 - Ferric chloride.  

Code of Federal Regulations, 2010 CFR

...from iron and chlorine or from ferric oxide and hydrogen chloride. The pure material occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron (III) chloride hexahydrate, FeC13 . 6H2 0, CAS Reg. No. 10025-77-1)...

2010-04-01

274

21 CFR 184.1297 - Ferric chloride.  

...from iron and chlorine or from ferric oxide and hydrogen chloride. The pure material occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron (III) chloride hexahydrate, FeC13. 6H2 0, CAS Reg. No. 10025-77-1)...

2014-04-01

275

Vinyl Chloride Loss during Laboratory Holding Time  

Microsoft Academic Search

Because vinyl chloride is a potent human carcinogen, it is important that analytical results from groundwater samples accurately reflect levels of exposure to groundwater users. This study investigated the current allowable holding time of 14 days to determine if vinyl chloride is lost from samples during this time. Samples containing an initial concentration of 2 ?g\\/liter of vinyl chloride showed

Richard Soule; Daniel Symonik; David Jones; Doug Turgeon; Betsy Gerbec

1996-01-01

276

The third-order elastic constants of potassium chloride, sodium chloride and lithium fluoride  

Microsoft Academic Search

The complete set of third-order elastic constants of potassium chloride, sodium chloride and lithium fluoride have been measured at room temperature under conditions which eliminate the possibility that plastic deformation occurred during the experiments. A partial check on these values, provided by the pressure derivatives of the elastic constants, shows satisfactory agreement with experiment for potassium chloride and sodium chloride

J. R. Drabble; R. E. B. Strathen

1967-01-01

277

Hormonal Control of Calcium Homeostasis  

Microsoft Academic Search

Calcium homeostasis in the extracellular fluid is tightly controlled and defended physiologically. Hypercalce- mia always represents considerable underlying pathol- ogy and occurs when the hormonal control of calcium homeostasis is overwhelmed. The major hormones that are responsible for normal calcium homeostasis are parathyroid hormone and 1,25-dihydroxyvitamin D; these hormones control extracellular fluid calcium on a chronic basis. Over- or underproduction

Gregory R. Mundy; Theresa A. Guise

1999-01-01

278

Stoichiometry of Calcium Medicines  

ERIC Educational Resources Information Center

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

Pinto, Gabriel

2005-01-01

279

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

SciTech Connect

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

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

1991-03-01

280

The Spectrum of Gold Chloride  

Microsoft Academic Search

The spectrum of gold chloride vapor excited by streaming active nitrogen was photographed. It was found to consist of 43 bands comprising, for each isotope of AuCl, two intermingled systems in the green region. All the bands are shaded toward the red. No other bands were found between lambdalambda7000-2000. The band heads of each system were measured, and equations are

W. F. Ferguson

1928-01-01

281

Chloride flux out of Yellowstone National Park  

USGS Publications Warehouse

Monitoring of the chloride concentration, electrical conductivity, and discharge was carried out for the four major rivers of Yellowstone National Park from September 1982 to January 1984. Chloride flux out of the Park was determined from the measured values of chloride concentration and discharge. The annual chloride flux from the Park was 5.86 ?? 1010 g. Of this amount 45% was from the Madison River drainage basin, 32% from the Yellowstone River basin, 12% from the Snake River basin, and 11% from the Falls River basin. Of the annual chloride flux from the Yellowstone River drainage basin 36% was attributed to the Yellowstone Lake drainage basin. The geothermal contribution to the chloride flux was determined by subtracting the chloride contribution from rock weathering and atmospheric precipitation and is 94% of the total chloride flux. Calculations of the geothermal chloride flux for each river are given and the implications of an additional chloride flux out of the western Park boundary discussed. An anomalous increase in chloride flux out of the Park was observed for several weeks prior to the Mt. Borah earthquake in Central Idaho on October 28, 1983, reaching a peak value shortly thereafter. It is suggested that the rise in flux was a precursor of the earthquake. The information in this paper provides baseline data against which future changes in the hydrothermal systems can be measured. It also provides measurements related to the thermal contributions from the different drainage basins of the Park. ?? 1985.

Norton, D.R.; Friedman, I.

1985-01-01

282

Monitoring calcium concentration in dendritic spines of cultured hippocampal neurons with cameleons  

NASA Astrophysics Data System (ADS)

Transient and substantial elevation of postsynaptic calcium was important for hippocampal long-term potentiation (LTP), so detection of calcium changes in spine was necessary to understand the mechanisms underlying synaptic plasticity. Unfortunately most recent calcium fluorescence indicators severely perturbed calcium transients, and traditional cameleons" poor dynamic ranges prevented detection of changes of calcium. We presented a new method to monitor quantificationally free calcium concentration in dendritic spines with a new yellow cameleon (YC3.60) basing on culture of hippocampal neurons and calcium phosphate transfection technique and confocal microscopy with 458nm laser. In transiently transfected hippocampal neurons, the ratio of YFP to CFP was detected as FRET level. In our study, we got the parameters of YC3.60 excited with 458nm laser. Under control conditions, FRET levels in different dendritic spines of cultured hippocampal neurons were diverse but showed robust increases upon treatment with potassium chloride. FRET levels in different parts of hippocampal neurons were also different, the calcium concentration decreased with the distance from soma. These results suggested that the FRET methodology with YC3.60 could monitor calcium concentration in spines and it might be useful in analyzing mechanisms underlying synaptic plasticity.

Liu, Xiuli; Zhou, Wei; Li, Xiangning; Gong, Hui; Luo, Qingming

2005-03-01

283

[Microbial geochemical calcium cycle].  

PubMed

The participation of microorganisms in the geochemical calcium cycle is the most important factor maintaining neutral conditions on the Earth. This cycle has profound influence on the fate of inorganic carbon, and, thereby, on the removal of CO2 from the atmosphere. The major part of calcium deposits was formed in the Precambrian, when prokaryotic biosphere predominated. After that, calcium recycling based on biogenic deposition by skeletal organisms became the main process. Among prokaryotes, only a few representatives, e.g., cyanobacteria, exhibit a special calcium function. The geochemical calcium cycle is made possible by the universal features of bacteria involved in biologically mediated reactions and is determined by the activities of microbial communities. In the prokaryotic system, the calcium cycle begins with the leaching of igneous rock predominantly through the action of the community of organotrophic organisms. The release of carbon dioxide to the soil air by organotrophic aerobes leads to leaching with carbonic acid and soda salinization. Under anoxic conditions, of major importance is the organic acid production by primary anaerobes (fermentative microorganisms). Calcium carbonate is precipitated by secondary anaerobes (sulfate reducers) and to a smaller degree by methanogens. The role of the cyanobacterial community in carbonate deposition is exposed by stromatolites, which are the most common organo-sedimentary Precambrian structures. Deposition of carbonates in cyanobacterial mats as a consequence of photoassimilation of CO2 does not appear to be a significant process. It is argued that carbonates were deposited at the boundary between the "soda continent", which emerged as a result of subaerial leaching with carbonic acid, and the ocean containing Ca2+. Such ecotones provided favorable conditions for the development of the benthic cyanobacterial community, which was a precursor of stromatolites. PMID:11910807

Zavarzin, G A

2002-01-01

284

Oscillatory chloride current evoked by temperature jumps during muscarinic and serotonergic activation in Xenopus oocyte.  

PubMed

1. Membrane currents were recorded from voltage-clamped oocytes of Xenopus laevis, during temperature jumps imposed by a heating light. Resting oocytes usually showed little response, but large oscillatory membrane currents developed in response to cooling steps applied during activation of 'native' muscarinic receptors. 2. Similar temperature jump (Tjump) currents were seen during activation of oscillatory chloride currents mediated by muscarinic acetylcholine (ACh), serotonin, glutamate and noradrenaline receptors, expressed in the oocyte following injection with messenger ribonucleic acid (mRNA) from rat brain. The Tjump response during muscarinic activation was selectively blocked by atropine, and that during serotonergic activation by methysergide. In contrast, the 'smooth' membrane currents elicited by nicotinic ACh, kainate and gamma-aminobutyric acid (GABA) were not accompanied by Tjump responses. 3. Rapid cooling of the oocyte gave larger Tjump currents than a gradual cooling over a few seconds. The size of the Tjump current elicited by a fixed cooling step increased linearly with the preceding time of warming, becoming maximal at intervals greater than about 100 s. 4. The Tjump current was inward at a clamp potential of -60 mV and reversed direction at about -22 mV, which corresponds to the chloride equilibrium potential in the oocyte. In low-chloride solution the reversal potential was shifted to more positive potentials, but it was almost unchanged by changes in potassium and sodium concentration. The size of the Tjump current decreased as the membrane potential was made more negative than about -40 mV. 5. The period of oscillation of the Tjump current increased with decreasing temperature, following a Q10 of 3.15. Depolarization also caused a small increase in period. 6. The Tjump current was not abolished in calcium-free solution, or by addition of manganese or lanthanum to the bathing solution. However, it was abolished by intracellular injection of the calcium-chelating agent EGTA. 7. Intracellular injection of inositol 1,4,5-trisphosphate evoked an oscillatory membrane current, during which Tjump responses developed similar to those after muscarinic activation. Intracellular injection of calcium evoked a chloride current, but this was not accompanied by Tjump responses. 8. We conclude that the oscillatory currents evoked by temperature jumps arise from chloride channels activated by intracellular calcium. This calcium is probably mobilized from intracellular stores by inositol trisphosphate which is liberated as a result of activation of muscarinic receptors, and also receptors for serotonin and glutamate.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2821235

Miledi, R; Parker, I; Sumikawa, K

1987-02-01

285

Calcium supplementation during sepsis exacerbates organ failure and mortality via calcium/calmodulin-dependent protein kinase kinase (CaMKK) signaling  

PubMed Central

Background Calcium plays an essential role in nearly all cellular processes. As such, cellular and systemic calcium concentrations are tightly regulated. During sepsis derangements in such tight regulation frequently occur, and treating hypocalcemia with parenteral calcium administration remains the current practice guideline. Objective We investigated whether calcium administration worsens mortality and organ dysfunction using an experimental murine model of sepsis and explored the mechanistic role of the family of calcium/calmodulin-dependent protein kinases in mediating these physiologic effects. To highlight the biological relevance of these observations, we conducted a translational study of the association between calcium administration, organ dysfunction and mortality among a cohort of critically ill septic ICU patients Design Prospective, randomized controlled experimental murine study. Observational clinical cohort analysis. Setting University research laboratory. Eight ICUs at a tertiary care center. Patients 870 septic ICU patients. Subjects C57BL/6 and CaMKK?/? mice. Interventions Mice underwent cecal ligation and puncture polymicrobial sepsis and were administered calcium chloride (0.25 or 0.25 mg/kg) or normal saline. Measurements and Main Results Administering calcium chloride to septic C57BL/6 mice heightened systemic inflammation and vascular leak, exacerbated hepatic and renal dysfunction, and increased mortality. These events were significantly attenuated in CaMKK?/? mice. In a risk–adjusted analysis of septic patients, calcium administration was associated with an increased risk of death, OR 1.92 (95% CI 1.00–3.68, p=0.049), a significant increase in the risk of renal dysfunction, OR 4.74 (95% CI 2.48–9.08, p<0.001), and a significant reduction in ventilator free days, mean decrease 3.29 days (0.50–6.08 days, p=0.02). Conclusions Derangements in calcium homeostasis occur during sepsis that are sensitive to calcium administration. This altered calcium signaling, transduced by the CaMKK cascade, mediates heightened inflammation and vascular leak that culminates in elevated organ dysfunction and mortality. In the clinical management of septic patients calcium supplementation provides no benefit and may impose harm. PMID:23887235

Collage, Richard D.; Howell, Gina M.; Zhang, Xianghong; Stripay, Jennifer L.; Lee, Janet S.; Angus, Derek C.; Rosengart, Matthew R.

2013-01-01

286

Effects of minor constituents in calcium silicate insulation on the corrosion of underground heat distribution systems. Final report  

SciTech Connect

This report presents the results of an investigation of the harmful corrosive effects of minor constituents in calcium silicate insulation on prefabricated steel conduit underground heat distribution systems. The research showed that the leachable chloride concentrations of commercially available calcium silicate insulation can contribute greatly to the corrosion of underground heat distribution systems and that the corrosion is aggravated if leaks in the system continue for long periods of time. Corrective measures are recommended to minimize this type of corrosion.

Segan, E.G.; Blackman, E.W.; March, C.

1984-05-01

287

Suspension of the calcium-sensitive human beta-caseins by human kappa-casein.  

PubMed

The beta-casein (CN) fraction of human milk exists as a single protein entity phosphorylated at various levels from zero to five (beta-CN-0P to beta-CN-5P). Since the beta-CN fraction is precipitated by the calcium ions in milk, a stabilizing protein is needed to form a suspension of casein micelles for ready ingestion by the infant. That stabilization is known to be carried out by kappa-CN but it is also thought possible that the 0P and 1P beta-CN moieties may play a role. To examine the effects of different phosphorylation levels, 10 mM CaCl2 was added to each of the purified proteins phosphorylated (P) at different levels. Without kappa-CN, precipitation of the different beta-CN forms varied from 78 to 99%. Human kappa-CN was then added to each to give kappa/beta molar ratios varying from 0.01 to 0.25. Some stabilization was observed even at the lowest ratio and more than 90% of the protein was suspended in all cases at the highest ratio. Interaction of low levels of kappa-CN with the different forms of beta-CN to create a suspension was somewhat dependent on the phosphorylation level and the possibility of forming intra- or intermolecular Ca2+ bridges or cross-links. Similar ratios of the beta-CN-4P to either the 0P or 1P form and of the 2P to the 1P form showed that neither the 0P nor 1P form had any stabilizing ability. In fact, coprecipitation occurred so that with either the 4P or 2P forms present, higher percentages of the 0P and 1P forms precipitated. PMID:12146463

Sood, S M; Slatter, C W

2002-06-01

288

Calcium revisited: part I  

PubMed Central

In February 2013, the US Preventive Services Task Force (see www.uspreventiveservicestaskforce.org) recommended ‘against daily supplementation with 400?IU or less of vitamin D3 and 1000, mg or less of calcium for the primary prevention of fractures in non institutionalized postmenopausal women', which illustrates the divergence of opinions. This review wants to shed an objective light on the importance of calcium for bone health. It cannot compete with an exhaustive analysis of the literature by an institute. It does not mention all significant references. But it highlights some pivotal studies from the past and it refers to recent studies that opened new views or added essential data to known facts. It also reflects the personal perception of the author. The first part deals mainly with intake, absorption, needs and recommendations; the second part will discuss the effects of calcium and its supplements on bone. PMID:24422133

Burckhardt, Peter

2013-01-01

289

An XAFS Study of Niobium chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride  

SciTech Connect

Niobium chloride was studied with extended X-ray absorption fine structure spectroscopy (EXAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Although anhydrous Nb2Cl10 is more soluble in the basic melt than in the acidic melt, the EXAFS data shows that the coordination shell around the niobium does not change in the different ionic liquids. Both the acidic and basic melts show a coordination of five chlorides in the first shell. This indicates that in this series of ionic liquids, the Nb2Cl10 breaks up into two NbCl5 entities in both the acidic and the basic melts.

D Roeper; K Pandya; G Cheek; W OGrady

2011-12-31

290

Calcium absorption from a new calcium delivery system (CCM)  

Microsoft Academic Search

Absorption of calcium from a highly soluble form of calcium, a mixed calcium citrate-malate* salt (CCM), was tested against calcium carbonate and milk in both rats and humans. The rat method estimated absorption from\\u000a the 6-day retention of an oral tracer, and the human method employed the standard double-isotope procedure. CCM was given\\u000a both as a dry powder and in

Kenneth T. Smith; Robert P. Heaney; Lawrence Flora; Sharilyn M. Hinders

1987-01-01

291

Nuclear calcium signaling.  

PubMed

Calcium is the major intracellular messenger linking synaptic activity in neurons to gene expression to control diverse functions including adaptive responses to synaptic activity as well as survival and death (Bading et al. 1993; Hardingham et al. 1997; Chawla and Bading 2001; West et al. 2001; Zhang et al. 2007; Flavell and Greenberg 2008; Mellstrom et al. 2008; Redmond 2008; Wayman et al. 2008; Bootman et al. 2009; Zhang et al. 2009; Hardingham and Bading 2010). Calcium entry at the synapse acts locally to activate signaling cascades which regulate posttranslational modifications essential for synaptic plasticity, such as the insertion of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) into the postsynaptic membrane (Soderling 2000; Malinow and Malenka 2002; Ehrlich and Malinow 2004). Synaptic activity can also evoke calcium signals in the nucleus which regulate gene pools largely through the phosphorylation of cAMP response element-binding protein (CREB) and its coactivator, CREB-binding protein (CBP) (Bading et al. 1993; Hardingham et al. 1997; Hardingham et al. 1999; Hu et al. 1999; Hardingham et al. 2001b; Impey et al. 2002; Zhang et al. 2009). Distinct mechanisms have been proposed to mediate synaptically generated calcium signals in subcompartments of pyramidal neurons; N-methyl-D -aspartate receptors (NMDARs) and ryanodine receptors have been implicated in the spine, inositol 3,4,5 triphosphate (IP3) receptors in the dendrites, and L-type voltage-gated calcium channels (VGCCs) at the soma and nucleus, although both NMDARs and IP3 receptors can also contribute to somatic and nuclear calcium signals under certain stimulation conditions (Nakamura et al. 1999; Bardo et al. 2006; Raymond and Redman 2006; Watanabe et al. 2006; Hong and Ross 2007; Hagenston et al. 2008; Bengtson et al. 2010). We review here the calcium signaling pathways underlying synaptically activated gene transcription leading to long-lasting changes in synaptic efficacy and memory as well as the physiological mechanisms by which synaptic activity evokes nuclear calcium signals. PMID:22351065

Bengtson, C Peter; Bading, Hilmar

2012-01-01

292

Calcium and olfactory transduction.  

PubMed

1. Inorganic cations, organic calcium antagonists, and calmodulin antagonists were applied to olfactory epithelia of frogs (Rana pipiens) while recording electroolfactogram (EOG) responses. 2. Inorganic cations inhibited EOGs in a rank order, reflecting their calcium channel blocking potency: La3+ greater than Zn2+ greater than Cd2+ greater than Al3+ greater than Ca2+ greater than Sr2+ greater than Co2+ greater than Ba2+ greater than Mg2+. Barium ion significantly enhanced EOGs immediately following application. 3. Diltiazem and verapamil produced dose-dependent EOG inhibition. 4. Calmodulin antagonists inhibited EOGs without correlation to their anti-calmodulin potency. PMID:2904344

Winegar, B D; Rosick, E R; Schafer, R

1988-01-01

293

Calcium carbonate with magnesium overdose  

MedlinePLUS

The combination of calcium carbonate and magnesium is commonly found in antacids, which are medicines that provide heartburn relief. Calcium carbonate with magnesium overdose occurs when someone accidentally or ...

294

Low-chlorides mud limits disposal costs  

Microsoft Academic Search

A low chloride potassium\\/polymer mud has been used to drill water sensitive shales. The fluid contained 3,000 ppm K\\/sup +\\/, and only 300 ppm or less chlorides. The pH was kept below 10.5. The system consisted of an organic potassium source and a high molecular weight polymer. Upon completion, the pit contained only 278 ppm chlorides. Disposal costs were greatly

1986-01-01

295

Metal chloride cathode for a battery  

NASA Technical Reports Server (NTRS)

A method of fabricating a rechargeable battery is disclosed which includes a positive electrode which contains a chloride of a selected metal when the electrode is in its active state. The improvement comprises fabricating the positive electrode by: providing a porous matrix composed of a metal; providing a solution of the chloride of the selected metal; and impregnating the matrix with the chloride from the solution.

Bugga, Ratnakumar V. (inventor); Distefano, Salvador (inventor); Bankston, C. Perry (inventor)

1991-01-01

296

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2011 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2011-04-01

297

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2010 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2010-04-01

298

21 CFR 184.1199 - Calcium gluconate.  

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2014-04-01

299

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2013 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2013-04-01

300

21 CFR 184.1199 - Calcium gluconate.  

Code of Federal Regulations, 2012 CFR

...1199 Calcium gluconate. (a) Calcium gluconate ([CH2 OH(CHOH...Reg. No. 299-28-5) is the calcium salt of gluconic acid which may...neutralization of gluconic acid with lime or calcium carbonate. (b) The...

2012-04-01

301

21 CFR 184.1191 - Calcium carbonate.  

...1) As a byproduct in the “Lime soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the “Carbonation process”; or (3) By precipitation of calcium carbonate from calcium...

2014-04-01

302

Chloride ingress in cement paste and mortar  

SciTech Connect

In this paper chloride ingress in cement paste and mortar is followed by electron probe microanalysis. The influence of several paste and exposure parameters on chloride ingress are examined (e.g., water-cement ratio, silica fume addition, exposure time, and temperature). The measurements are modelled on Fick's law modified by a term for chloride binding. Inclusion of chloride binding significantly improves the profile shape of the modelled ingress profiles. The presence of fine aggregate and formation of interfacial transition zones at paste-aggregate boundaries does not significantly affect diffusion rates.

Jensen, O.M.; Hansen, P.F.; Coats, A.M.; Glasser, F.P.

1999-09-01

303

Fabrication Of Metal Chloride Cathodes By Sintering  

NASA Technical Reports Server (NTRS)

Transition-metal chloride cathodes for use in high-temperature rechargeable sodium batteries prepared by sintering transition-metal powders mixed with sodium chloride. Need for difficult and dangerous chlorination process eliminated. Proportions of transition metal and sodium chloride in mixture adjusted to suit specific requirements. Cathodes integral to sodium/metal-chloride batteries, which have advantages over sodium/sulfur batteries including energy densities, increased safety, reduced material and thermal-management problems, and ease of operation and assembly. Being evaluated for supplying electrical power during peak demand and electric vehicles.

Bugga, Ratnakumar V.; Di Stefano, Salvador; Bankston, C. Perry

1992-01-01

304

Enrofloxacin hydro­chloride dihydrate  

PubMed Central

The asymmetric unit of the title compound, C19H23FN3O3 +·Cl?·2H2O [systematic name: 4-(3-carb­oxy-1-cyclo­propyl-6-fluoro-4-oxo-1,4-di­hydro­quin­o­lin-7-yl)-1-ethyl­piperazin-1-ium chloride dihydrate], consists of two independent monocations of the protonated enrofloxacin, two chloride anions and four water mol­ecules. In the cations, the piperazinium rings adopt chair conformations and the dihedral angles between the cyclo­propyl ring and the 10-membered quinoline ring system are 56.55?(2) and 51.11?(2)°. An intra­molecular O—H?O hydrogen bond is observed in each cation. In the crystal, the components are connected via O—H?Cl, N—H?Cl and O—H?O hydrogen bonds, and a ?–? inter­action between the benzene rings [centroid–centroid distance = 3.6726?(13)?Å], resulting in a three-dimensional array. PMID:24826167

Miranda-Calderón, Jorge E.; Gutiérrez, Lilia; Flores-Alamo, Marcos; García-Gutiérrez, Ponciano; Sumano, Héctor

2014-01-01

305

Calcium silicate insulation structure  

DOEpatents

An insulative structure including a powder-filled evacuated casing utilizes a quantity of finely divided synthetic calcium silicate having a relatively high surface area. The resultant structure-provides superior thermal insulating characteristics over a broad temperature range and is particularly well-suited as a panel for a refrigerator or freezer or the insulative barrier for a cooler or a insulated bottle.

Kollie, Thomas G. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)

1995-01-01

306

The Plasma Membrane Calcium Pump  

NASA Technical Reports Server (NTRS)

Three aspect of cellular calcium metabolism in animal cells was discussed including the importance of the plasma membrane in calcium homeostasis, experiments dealing with the actual mechanism of the calcium pump, and the function of the pump in relationship to the mitochondria and to the function of calmodulin in the intact cell.

Rasmussen, H.

1983-01-01

307

Defoaming effect of calcium soap  

Microsoft Academic Search

The effect of calcium oleate on foam stability was studied for aqueous solutions of two commonly used surfactants (anionic and nonionic) under alkaline conditions in the absence of oil. For the anionic surfactant, defoaming by calcium oleate appears to involve two mechanisms. One is that oleate and calcium ions are presumably incorporated into the surfactant monolayers with a resulting decrease

Hui Zhang; Clarence A. Miller; Peter R. Garrett; Kirk H. Raney

2004-01-01

308

Osteoinduction by calcium phosphate biomaterials  

Microsoft Academic Search

Different materials were implanted in muscles of dogs to study the osteoinduction of calcium phosphate biomaterials. Bone formation was only seen in calcium phosphate biomaterials with micropores, and could be found in hydroxyapatite (HA) ceramic, tricalcium phosphate\\/hydroxyapatite ceramic (BCP), ß-TCP ceramic and calcium phosphate cement. The osteoinductive potential was different in different materials. The results indicate that osteoinduction can be

Huipin Yuan; Zongjian Yang; Yubao Li; Xingdong Zhang; J. D. De Bruijn; K. De Groot

1998-01-01

309

Potentiometric titration of chloride in plant tissue extracts using the chloride ion electrode  

Microsoft Academic Search

Use of the chloride specific ion electrode to determine chloride in plants was evaluted. Direct potentiometric determination of chloride by the electrode resulted in unreproducible and extremely high chloride values. However, use of this electrode to indicate the end point in titration of the tissue?extract mixture with AgNO3 gave results nearly identical to those obtained by the Mohr procedure. The

R. L. LaCroix; D. R. Keeney; L. M. Walsh

1970-01-01

310

Halotolerance is enhanced in carrot callus by sensing hypergravity: influence of calcium modulators and cytochalasin D.  

PubMed

Carrot callus was centrifuged at 10 g and compared to callus growing at 1 g on agar in the presence of increasing sodium chloride concentrations. Growth after 14 days was enhanced in the centrifuged samples versus samples kept at 1 g. This effect was not found when the samples were grown on potassium chloride. At 50 mM NaCl, the calcium ionophore ionomycin was applied to centrifuged and noncentrifuged callus samples. In both experiments, the growth of callus increased with increasing ionomycin concentrations but under 10 g this increase was more enhanced. As inhibitors of calcium influx, lanthanum and gadolinium chloride were chosen in the presence of 50 mM NaCl. Both inhibitors inhibited growth at 1 g at low concentrations of around 2 microM, whereas the centrifuged samples were not or much less so inhibited. We tested an involvement of actin by application of cytochalasin D to callus grown in the presence of 50 mM NaCl. In both types of samples, growth at 1 g and growth at 10 g, cytochalasin D enhanced growth but the effect was clearly stronger at 10 g than at 1 g. As increased halotolerance was only observed in the presence of increased sodium ions, not potassium ions, and as halotolerance is known to be induced by an influx of calcium, the data suggest that a calcium influx induced by hypergravity and possibly modulated by actin caused the observed increase in halotolerance at 10 g. PMID:17180496

Scherer, G F E

2006-12-01

311

A model of propagating calcium-induced calcium release mediated by calcium diffusion  

Microsoft Academic Search

The effect of sudden local fluctuations of the free sarcoplasmic (Ca++)i in cardiac cells on calcium release and calcium uptake by the sarcoplasmic reticulum (SR) was calculated with the aid of a simplified model of SR calcium handling. The model was used to evaluate whether propagation of calcium tran- sients and the range of propagation velocities observed experimentally (0.05-15 mm

PETER H. BACKX; PIETER P. DE TOMBE; JURJEN H. K. VAN DEEN

1989-01-01

312

Chloride Analysis of RFSA Second Campaign Dissolver Solution  

SciTech Connect

The dissolver solution from the second RFSA campaign was analyzed for chloride using the recently-developed turbidimetric method. Prior to chloride removal in head end, the solution contained 1625 ppm chloride. After chloride removal with Hg(I) and prior to feeding to solvent extraction, the solution contained only 75 ppm chloride. This report discusses those analysis results.

Holcomb, H.P.

2001-05-17

313

Inhibitory effects of calmodulin antagonists on urinary enzyme excretion in rats after nephrotoxic doses of mercuric chloride  

SciTech Connect

Prochlorperazine, a phenothiazine antiemetic, has been reported to protect rats against mercuric chloride (HgCl/sub 2/)-induced nephrotoxicity. Mercuric ion and 12 other divalent metal ions of toxicologic importance inhibit the activity of calmodulin, a ubiquitous intracellular calcium receptor and regulatory protein, at physiologically relevant concentrations. Phenothiazines, including prochlorperazine, are reversible calmodulin antagonists, and as such they interact with divalent calcium at the level of calmodulin. It was of interest therefore to evaluate the comparative effects of several phenothiazines on HgCl/sub 2/-induced nephrotoxicity in rats.

Harrison, S.D. Jr.; Cox, J.L.; Giles, R.C. Jr.

1985-03-01

314

Voltage-Gated Calcium Channels  

NASA Astrophysics Data System (ADS)

Voltage Gated Calcium Channels is the first comprehensive book in the calcium channel field, encompassing over thirty years of progress towards our understanding of calcium channel structure, function, regulation, physiology, pharmacology, and genetics. This book balances contributions from many of the leading authorities in the calcium channel field with fresh perspectives from risings stars in the area, taking into account the most recent literature and concepts. This is the only all-encompassing calcium channel book currently available, and is an essential resource for academic researchers at all levels in the areas neuroscience, biophysics, and cardiovascular sciences, as well as to researchers in the drug discovery area.

Zamponi, Gerald Werner

315

A Synthetic Chloride Channel Relaxes Airway Smooth Muscle of the Rat  

PubMed Central

Synthetic ion channels may have potential therapeutic applications, provided they possess appropriate biological activities. The present study was designed to examine the ability of small molecule-based synthetic Cl– channels to modulate airway smooth muscle responsiveness. Changes in isometric tension were measured in rat tracheal rings. Relaxations to the synthetic chloride channel SCC-1 were obtained during sustained contractions to KCl. The anion dependency of the effect of SCC-1 was evaluated by ion substitution experiments. The sensitivity to conventional Cl– transport inhibitors was also tested. SCC-1 caused concentration-dependent relaxations during sustained contractions to potassium chloride. This relaxing effect was dependent on the presence of extracellular Cl– and HCO3?. It was insensitive to conventional Cl– channels/transport inhibitors that blocked the cystic fibrosis transmembrane conductance regulator and calcium-activated Cl– channels. SCC-1 did not inhibit contractions induced by carbachol, endothelin-1, 5-hydroxytryptamine or the calcium ionophore A23187. SCC-1 relaxes airway smooth muscle during contractions evoked by depolarizing solutions. The Cl– conductance conferred by this synthetic compound is distinct from the endogenous transport systems for chloride anions. PMID:23049786

Yau, Kwok-hei; Mak, Judith Choi-wo; Leung, Susan Wai-sum; Yang, Dan; Vanhoutte, Paul M.

2012-01-01

316

Processing of mercurous chloride in reduced gravity  

Microsoft Academic Search

In a joint experiment between the Northrop-Grumman Science and Technology Center and the University of Alabama in Huntsville, Consortium for Materials Development in Space, single crystals of mercurous chloride were grown in the Space Experiment Facility (SEF) transparent furnace that was flown on Spacehab 4 in May 1996. Mercurous chloride is an acousto-optical material with an unusually low acoustic velocity

C. Watson; N. B. Singh; A. Thomas; A. E. Nelson; T. O. Rolin; J. Griffin; G. Haulenbeek; N. Daniel; J. Seaquist; C. Cacioppo; J. Weber; Maria I. Zugrav; R. J. Naumann

1996-01-01

317

STUDIES OF POINT DEFECTS IN SILVER CHLORIDE  

Microsoft Academic Search

Experiments were made on excess point defects introduced into single ; crystals of silver chloride by pulsed elastic extension or by rapid cooling from ; high temperature. Point defects are created by plastic deformation much less ; efficiently in silver chloride than in other substances that have been studied. ; Interstitial silver ions so produced have a lifetime of the

Howard Layer; Lawrence Slifkin

1962-01-01

318

Tri-benzyl-ammonium chloride.  

PubMed

Single crystals of the title salt, C21H21NH(+)·Cl(-), were isolated as a side product from the reaction involving [(C6H5CH2)3NH]2[HPO4] and Sn(CH3)3Cl in ethanol. Both the cation and the anion are situated on a threefold rotation axis. The central N atom in the cation has a slightly distorted tetra-hedral environment, with angles ranging from 107.7 to 111.16?(10)°. In the crystal, the tri-benzyl-ammonium cations and chloride anions are linked through N-H?Cl and C-H?Cl hydrogen bonds, leading to the formation of infinite chains along [001]. The crystal studied was a merohedral twin. PMID:24860409

Diallo, Waly; Diop, Libasse; Plasseraud, Laurent; Cattey, Hélène

2014-05-01

319

Tri-benzyl-ammonium chloride  

PubMed Central

Single crystals of the title salt, C21H21NH+·Cl?, were isolated as a side product from the reaction involving [(C6H5CH2)3NH]2[HPO4] and Sn(CH3)3Cl in ethanol. Both the cation and the anion are situated on a threefold rotation axis. The central N atom in the cation has a slightly distorted tetra­hedral environment, with angles ranging from 107.7 to 111.16?(10)°. In the crystal, the tri­benzyl­ammonium cations and chloride anions are linked through N—H?Cl and C—H?Cl hydrogen bonds, leading to the formation of infinite chains along [001]. The crystal studied was a merohedral twin. PMID:24860409

Diallo, Waly; Diop, Libasse; Plasseraud, Laurent; Cattey, Helene

2014-01-01

320

Sodium-metal chloride batteries  

NASA Technical Reports Server (NTRS)

It was concluded that rapid development in the technology of sodium metal chloride batteries has been achieved in the last decade mainly due to the: expertise available with sodium sulfur system; safety; and flexibility in design and fabrication. Long cycle lives of over 1000 and high energy densities of approx. 100 Wh/kg have been demonstrated in both Na/FeCl2 and Na/NiCl2 cells. Optimization of porous cathode and solid electrolyte geometries are essential for further enhancing the battery performance. Fundamental studies confirm the capabilities of these systems. Nickel dichloride emerges as the candidate cathode material for high power density applications such as electric vehicle and space.

Ratnakumar, B. V.; Attia, A. I.; Halpert, G.

1992-01-01

321

Hydrocracking with molten zinc chloride catalyst containing 2-12% ferrous chloride  

DOEpatents

In a process for hydrocracking heavy aromatic polynuclear carbonaceous feedstocks to produce hydrocarbon fuels boiling below about 475.degree. C. by contacting the feedstocks with hydrogen in the presence of a molten zinc chloride catalyst and thereafter separating at least a major portion of the hydrocarbon fuels from the spent molten zinc chloride catalyst, an improvement comprising: adjusting the FeCl.sub.2 content of the molten zinc chloride to from about 2 to about 12 mol percent based on the mixture of ferrous chloride and molten zinc chloride.

Zielke, Clyde W. (McMurray, PA); Bagshaw, Gary H. (Library, PA)

1981-01-01

322

Stochastic calcium mechanisms cause dendritic calcium spike variability.  

PubMed

Bursts of dendritic calcium spikes play an important role in excitability and synaptic plasticity in many types of neurons. In single Purkinje cells, spontaneous and synaptically evoked dendritic calcium bursts come in a variety of shapes with a variable number of spikes. The mechanisms causing this variability have never been investigated thoroughly. In this study, a detailed computational model using novel simulation routines is applied to identify the roles that stochastic ion channels, spatial arrangements of ion channels, and stochastic intracellular calcium have toward producing calcium burst variability. Consistent with experimental recordings from rats, strong variability in the burst shape is observed in simulations. This variability persists in large model sizes in contrast to models containing only voltage-gated channels, where variability reduces quickly with increase of system size. Phase plane analysis of Hodgkin-Huxley spikes and of calcium bursts identifies fluctuation in phase space around probabilistic phase boundaries as the mechanism determining the dependence of variability on model size. Stochastic calcium dynamics are the main cause of calcium burst fluctuations, specifically the calcium activation of mslo/BK-type and SK2 channels. Local variability of calcium concentration has a significant effect at larger model sizes. Simulations of both spontaneous and synaptically evoked calcium bursts in a reconstructed dendrite show, in addition, strong spatial and temporal variability of voltage and calcium, depending on morphological properties of the dendrite. Our findings suggest that stochastic intracellular calcium mechanisms play a crucial role in dendritic calcium spike generation and are therefore an essential consideration in studies of neuronal excitability and plasticity. PMID:24089492

Anwar, Haroon; Hepburn, Iain; Nedelescu, Hermina; Chen, Weiliang; De Schutter, Erik

2013-10-01

323

Calcium in Plants  

PubMed Central

Calcium is an essential plant nutrient. It is required for various structural roles in the cell wall and membranes, it is a counter?cation for inorganic and organic anions in the vacuole, and the cytosolic Ca2+ concentration ([Ca2+]cyt) is an obligate intracellular messenger coordinating responses to numerous developmental cues and environmental challenges. This article provides an overview of the nutritional requirements of different plants for Ca, and how this impacts on natural flora and the Ca content of crops. It also reviews recent work on (a) the mechanisms of Ca2+ transport across cellular membranes, (b) understanding the origins and specificity of [Ca2+]cyt signals and (c) characterizing the cellular [Ca2+]cyt?sensors (such as calmodulin, calcineurin B?like proteins and calcium?dependent protein kinases) that allow plant cells to respond appropriately to [Ca2+]cyt signals. PMID:12933363

WHITE, PHILIP J.; BROADLEY, MARTIN R.

2003-01-01

324

Complexometric Determination of Calcium  

NASA Astrophysics Data System (ADS)

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

Nielsen, S. Suzanne

325

Chloride regulatory mechanisms and their influence on neuronal excitability.  

E-print Network

??The chloride concentration in neurons is in general established by the precise functional expression of the sodium-potassium-chloride cotransporter one (NKCC1) and the potassium-chloride cotransporter two… (more)

Rinke, Ilka

2010-01-01

326

Complexometric Determination of Calcium  

Microsoft Academic Search

\\u000a Ethylenediaminetetraacetate (EDTA) complexes with numerous mineral ions, including calcium and magnesium. This reaction can\\u000a be used to determine the amount of these minerals in a sample by a complexometric titration. Endpoints in the titration are\\u000a detected using indicators that change color when they complex with mineral ions. Calmagite and eriochrome black T (EBT) are\\u000a such indicators that change from blue

S. Suzanne Nielsen

2010-01-01

327

Calcium signaling in plants  

Microsoft Academic Search

.   Changes in the cytosolic concentration of calcium ions ([Ca2+]i) play a key second messenger role in signal transduction. These changes are visualized by making use of either Ca2+-sensitive fluorescent dyes or the Ca2+-sensitive photoprotein, aequorin. Here we describe the advances made over the last 10 years or so, which have conclusively\\u000a demonstrated a second messenger role for [Ca2+]i in

J. J. Rudd; V. E. Franklin-Tong

1999-01-01

328

Estimating Calcium Requirements  

Microsoft Academic Search

\\u000a Nutrient requirements are used by many groups to determine food choices and meal plans for feeding people across the lifespan.\\u000a They are used to evaluate sources of nutrients and for food labels to educate the consumer. Requirements also provide a guideline\\u000a to determine whether supplements are needed. If calcium requirements are underestimated, inadequate intakes are more likely,\\u000a which may compromise

Connie M. Weaver; Kathleen M. Hill

329

Chloride penetration into concrete structures in the marine atmosphere zone – Relationship between deposition of chlorides on the wet candle and chlorides accumulated into concrete  

Microsoft Academic Search

The relationship between chlorides from marine aerosol and chlorides accumulated into concrete is discussed in this paper. The experimental programme comprised an environmental characterisation, with climatic and chloride deposition data, and a study of chloride penetration into concrete based on natural exposure of specimens in a marine atmosphere zone. Results show that salt concentration in marine aerosol strongly decreases in

G. R. Meira; C. Andrade; I. J. Padaratz; C. Alonso; J BORBAJR

2007-01-01

330

INDUCTION OF CRYSTALLIZATION OF SPECIFIC CALCIUM OXALATE HYDRATES IN MICELLAR SOLUTIONS OF SURFACTANTS  

Microsoft Academic Search

The influence of octaethylene glycol mono-n-hexadecyl ether (C16EO8) and sodium dodecyl sulphate (SDS) on the crystallization of calcium oxalate from 0.3 mol dm sodium chloride solutions has been investigated. The critical micellar concentration (CMC) of C16EO8 in water and 0.3 mol dm NaCl was determined by surface tension measurements (CMCH2O=CMCNaCl = 7.2.10 mol dm). The kinetics of precipitation of calcium oxalate was followed

H. Füredi-Milhofer; R. Bloch; D. Skrtic; N. Filipovic-Vincekovic; N. Garti

1993-01-01

331

The Influence of pH on the Oxygen Isotope Composition of Calcium Carbonate  

NASA Astrophysics Data System (ADS)

Oxygen isotope fractionation between calcium carbonate and water is temperature-dependent and can therefore be used as a paleothermometer. Although oxygen isotope fractionation is expected from principles of equilibrium isotopic partitioning, the temperature-dependence remains uncertain because other factors, such as slow exchange between dissolved inorganic carbon (DIC) species and water, can obscure the temperature signal. Oxygen isotopic equilibrium between aqueous solution and calcium carbonate includes two distinct equilibria: equilibrium of the DIC species in solution (i.e., CO2(aq), H2CO3, HCO3-, and CO32-) with water, and equilibrium between the dissolved inorganic carbon with the precipitated carbonate. To isolate kinetic isotope effects that arise at the mineral-solution interface, isotopic equilibrium among DIC species must be maintained. This can be accomplished by dissolving the enzyme carbonic anhydrase (CA) into the solution, thereby reducing the time required for isotopic equilibration between DIC species by approximately two orders of magnitude between pH 7.7 and 9.3. We conduct calcite growth experiments aimed specifically at measuring the pH-dependence of kinetic oxygen isotope effects during precipitation of calcite. We precipitated calcite from aqueous solution at a constant pH and controlled supersaturation over the pH range 7.7-9.3. For each experiment, a gas mixture of N2 and CO2 is constantly bubbled through a beaker containing ~1300 mL of solution (30 mM CaCl2 + 5 mM NH4Cl + 0.1 mM SrCl2). As CO2 from the gas dissolves into solution, calcite crystals grow on the beaker walls. The pH of the solution is maintained by use of an autotitrator with NaOH as the titrant. We control the temperature, pH, the pCO2 of the gas inflow, and the gas inflow rate, and monitor the total alkalinity, the pCO2 of the gas outflow, and the amount of NaOH added. A constant crystal growth rate of ~1.6 mmol/m2/hr is maintained over all experiments. We will present results from this set of experiments and discuss kinetic oxygen isotope effects in the context of a recently-developed ion-by-ion growth model of calcite.

Hunt, J. D.; Watkins, J. M.; Ryerson, F. J.; DePaolo, D. J.

2013-12-01

332

Methylene chloride poisoning in a cabinet worker.  

PubMed Central

More than a million workers are at risk for methylene chloride exposure. Aerosol sprays and paint stripping may also cause significant nonoccupational exposures. After methylene chloride inhalation, significant amounts of carbon monoxide are formed in vivo as a metabolic by-product. Poisoning predominantly affects the central nervous system and results from both carboxyhemoglobin formation and direct solvent-related narcosis. In this report, we describe a case of methylene chloride intoxication probably complicated by exogenous carbon monoxide exposure. The worker's presentation of intermittent headaches was consistent with both methylene chloride intoxication and carbon monoxide poisoning. The exposures and symptoms were corroborated by elevated carboxyhemoglobin saturations and a workplace inspection that documented significant exposures to both methylene chloride and carbon monoxide. When both carbon monoxide and methylene chloride are inhaled, additional carboxyhemoglobin formation is expected. Preventive efforts should include education, air monitoring, and periodic carboxyhemoglobin determinations. Methylene chloride should never be used in enclosed or poorly ventilated areas because of the well-documented dangers of loss of consciousness and death. Images Figure 1 PMID:10464079

Mahmud, M; Kales, S N

1999-01-01

333

Materials for Conoco zinc chloride hydrocracking process  

SciTech Connect

Use of zinc chloride to augment hydrogenation of coal and yield a high-octane gasoline product is the most significant feature of a coal liquefaction process being developed by Conoco Coal Development Company. The zinc chloride catalyst is regenerated in a fluidized sand bed, where the spent melt is mixed with air and hydrogen chloride at about 1000/sup 0/C. Recovery is completed at 370/sup 0/C in a condenser, where the zinc chloride is collected and the oxygen and sulfur are separated as H/sub 2/O and SO/sub 2/. The economic viability of the entire process is highly dependent on almost complete recovery of the zinc chloride. The severe environmental conditions of this recovery process cause unique materials problems. Although high-temperature oxidation and sulfidation are being studied in related programs, suitable materials to resist their combined effects along with those of chlorides have not yet been specifically addressed. Common engineering materials, such as the austenitic stainless steels and many nickel-base alloys, are unsuitable because of their inability to tolerate the elevated temperatures and sulfidation, respectively. The objectives of this task are to screen various metallic and ceramic materials for resistance to the zinc chloride recovery system environment and to determine the nature of the attack by exposing coupons to the simulated environment in the laboratory.

Baylor, V.B.; Keiser, J.R.; DeVan, J.H.

1980-01-01

334

Deuterium oxide normalizes blood pressure and vascular calcium uptake in Dahl salt-sensitive hypertensive rats  

SciTech Connect

This study examined the effect of 25% deuterium oxide in drinking water on systolic blood pressure, uptakes of calcium, and rubidium 86 by aortas of Dahl salt-sensitive rats on 0.4% (low) and 8% (high) sodium chloride (salt) diet. Twenty-four rats were divided into four groups. Groups I and II were on the low salt diet and groups III and IV on the high salt diet from 6 weeks of age. Additionally, at 10 weeks of age groups I and III were placed on 100% water and groups II and IV on 25% deuterium oxide. At 14 weeks, systolic blood pressure, uptakes of calcium, and rubidium 86 by aortas were significantly higher (p less than 0.01) in rats on the high salt diet as compared with those on the low salt diet. Deuterium oxide intake normalized systolic blood pressure and aortic calcium uptake but not aortic rubidium 86 uptake in hypertensive rats on the high salt diet. Deuterium oxide had no effect on blood pressure or aortic calcium uptake in rats on the low salt diet. The parallel increase in systolic blood pressure and vascular calcium uptake suggests that increased calcium uptake mechanisms are associated with hypertension in salt-sensitive Dahl rats. Furthermore, deuterium oxide appears to normalize elevated blood pressure in salt-sensitive hypertensive rats by normalizing elevated vascular (aortic) calcium uptake.

Vasdev, S.; Prabhakaran, V.; Sampson, C.A. (General Hospital, St. John's, Newfoundland (Canada))

1990-02-01

335

Verapamil protection against mercuric chloride-induced renal glomerular injury in rats.  

PubMed

We have examined the effects of the calcium channel blocker verapamil on the renal glomerular structural damage produced by mercuric chloride in rats. Verapamil (75 micrograms/kg body wt iv) was administered 30 min prior to mercuric chloride injection (HgCl2, 5 mg/kg body wt sc). Verapamil prevented the glomerular proteinuria observed in HgCl2-treated rats. Isolated glomeruli from mercury-treated rats 1 h after injection presented a diminished cross-sectional area as compared with control glomeruli (control [micron2], 26,310 +/- 2545; HgCl2 [micron2], 18,474 +/- 1828) and increased glomerular calcium content (control, 23 +/- 6 nmol/mg protein; HgCl2, 43 +/- 7 nmol/mg protein). Verapamil pretreatment prevented glomerular cross-sectional area (GCSA) diminution and glomerular calcium content rise (GCSA [micron2] Vp + Hg, 28,281 +/- 4654, Ca2+ [nmol/mg protein] Vp + Hg, 18 +/- 5). Renal sections prepared for immunohistochemical detection and histochemical analysis showed increased deposits of fibronectin and lipids and enhanced cellularity in glomerular structures from HgCl2-treated rats. Renal sections from animals pretreated with verapamil showed fibronectin and lipid contents not different from control sections and their histological studies did not show any changes when compared with control. Verapamil pretreatment also protected glomeruli from enhanced leukocyte content (myeloperoxidase activity/mg protein): control, 59 +/- 7; HgCl2, 134 +/- 10; Vp + Hg, 79 +/- 11). HgCl2 also contracts GCSA in vitro; Vp prevented this GCSA diminution. The results described in this study indicate that mercuric chloride nephrotoxicity may be associated not only with changes in renal glomerular haemodynamics, but also with a direct effect on glomerular cells. PMID:9853004

Girardi, G; Elías, M M

1998-10-01

336

APPLICATION OF VACUUM SALT DISTILLATION TECHNOLOGY FOR THE REMOVAL OF FLUORIDE AND CHLORIDE FROM LEGACY FISSILE MATERIALS  

SciTech Connect

Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and the Savannah River Site (SRS) HB-Line Facility designed, developed, tested, and successfully deployed a production-scale system for the distillation of sodium chloride (NaCl) and potassium chloride (KCl) from plutonium oxide (PuO{sub 2}). Subsequent efforts adapted the vacuum salt distillation (VSD) technology for the removal of chloride and fluoride from less-volatile halide salts at the same process temperature and vacuum. Calcium chloride (CaCl{sub 2}), calcium fluoride (CaF{sub 2}), and plutonium fluoride (PuF{sub 3}) were of particular concern. To enable the use of the same operating conditions for the distillation process, SRNL employed in situ exchange reactions to convert the less-volatile halide salts to compounds that facilitated the distillation of halide without removal of plutonium. SRNL demonstrated the removal of halide from CaCl{sub 2}, CaF{sub 2} and PuF{sub 3} below 1000 C using VSD technology.

Pierce, R.; Peters, T.

2011-11-01

337

Effect of modulation of protein kinase C on the cAMP-dependent chloride conductance in T84 cells.  

PubMed

The regulation of chloride conductance was investigated in the T84 human colon carcinoma cell line by the quenching of the fluorescent probe 6-methoxy-N-(3-sulfopropyl)quinolinium. The permeable cAMP analog 8-Br-cAMP (100 microM) and the calcium ionophore ionomycin (1 microM) activate a chloride conductance. A prolonged (4 h) preincubation of cells with phorbol 12-myristate 13-acetate (100 nM) or with the diacylglycerol analog 1-oleoyl-2-acetyl-glycerol (100 microM): (i) down-modulates to almost zero the protein kinase C activity in the membranes; (ii) inhibits the activation of the chloride conductance mediated by 8-Br-cAMP but not by calcium; (iii) reduces the mRNA without changing the expression of the protein product of the cystic fibrosis gene. The data suggest that PKC is essential for the activation of the cAMP-dependent chloride conductance in T84 cells. PMID:1383033

Dechecchi, M C; Rolfini, R; Tamanini, A; Gamberi, C; Berton, G; Cabrini, G

1992-10-12

338

Binary Nucleation of Water and Sodium Chloride  

SciTech Connect

Nucleation processes in the binary water-sodium chloride system are investigated in the sense of the classical nucleation theory (CNT). The CNT is modified to be able to handle the electrolytic nature of the system and is employed to investigate the acceleration of the nucleation process due to the presence of sodium chloride in the steam. This phenomenon, frequently observed in the Wilson zone of steam turbines, is called early condensation. Therefore, the nucleation rates of the water-sodium chloride mixture are of key importance in the power cycle industry.

Nemec, Thomas [Institute of Thermomechanics ASCR, Prague, Czech Republic; Marsik, Frantisek [Institute of Thermomechanics ASCR, Prague, Czech Republic; Palmer, Donald [ORNL

2005-01-01

339

INTEGUMENTARY LOSS OF CALCIUM.: 839  

Microsoft Academic Search

Integumentary calcium loss was studied in 16 healthy young men. The daily loss by the 16 ambulatory but relatively sedentary young men in 52 determinations of 6-day periods each was 8.7 ± 1.9 mgJm2 per day (average 15.8 mg\\/man per day). The amount lost was not influenced by calcium intake (0. 1 to 2.3 g\\/day). In contrast to urinary calcium

Jen-Yih Chu; Sheldon Margen; Doris Calloway; Francoise Costa; James A. Monteleone

1978-01-01

340

Calcium Phosphate Biomaterials: An Overview  

Microsoft Academic Search

Calcium phosphates are used by our body to build bones and are being applied to produce biomaterials for bone repair. It is\\u000a well-known that calcium phosphate biomaterials guide new bone formation, form a tight bond with the newly formed bone, and\\u000a are therefore, by definition, osteoconductive. Besides their osteoconductive property, it was found that calcium phosphate\\u000a biomaterials, only with specific

Huipin Yuan; KLAAS DE GROOT

341

Phenomics of Cardiac Chloride Channels  

PubMed Central

Forward genetic studies have identified several chloride (Cl?) channel genes, including CFTR, ClC-2, ClC-3, CLCA, Bestrophin, and Ano1, in the heart. Recent reverse genetic studies using gene targeting and transgenic techniques to delineate the functional role of cardiac Cl? channels have shown that Cl? channels may contribute to cardiac arrhythmogenesis, myocardial hypertrophy and heart failure, and cardioprotection against ischemia reperfusion. The study of physiological or pathophysiological phenotypes of cardiac Cl? channels, however, is complicated by the compensatory changes in the animals in response to the targeted genetic manipulation. Alternatively, tissue-specific conditional or inducible knockout or knockin animal models may be more valuable in the phenotypic studies of specific Cl? channels by limiting the effect of compensation on the phenotype. The integrated function of Cl? channels may involve multiprotein complexes of the Cl? channel subproteome. Similar phenotypes can be attained from alternative protein pathways within cellular networks, which are influenced by genetic and environmental factors. The phenomics approach, which characterizes phenotypes as a whole phenome and systematically studies the molecular changes that give rise to particular phenotypes achieved by modifying the genotype under the scope of genome/proteome/phenome, may provide more complete understanding of the integrated function of each cardiac Cl? channel in the context of health and disease. PMID:23720326

Duan, Dayue Darrel

2014-01-01

342

Original article Intestinal absorption of calcium  

E-print Network

Original article Intestinal absorption of calcium from yogurt in lactase-deficient subjects-tolerated and efficient source of calcium in subjects with lactase deficiency. calcium absorption / lactase-deficiency absorption of calcium (FACa) was measured using radioactive cal- cium and 200 mg of calcium carrier provided

Paris-Sud XI, Université de

343

High Blood Pressure and Calcium Antagonism  

Microsoft Academic Search

Calcium ions are intimately involved in many aspects of cardiovascular function. Modification of calcium homeostasis therefore represents a key target for pharmacological intervention to achieve therapeutic control of hypertension. The calcium channel blockers (CCBs) act by blocking calcium influx through voltage-dependent L (long-acting) channels without affecting calcium release from the sarcoplasmic reticulum. The effect of blocking these channels is a

José L. Palma-Gámiz

1997-01-01

344

Mechanical signalling, calcium and plant form  

Microsoft Academic Search

Calcium is a dynamic signalling molecule which acts to transduce numerous signals in plant tissues. The basis of calcium signalling is outlined and the necessity for measuring and imaging of calcium indicated. Using plants genetically transformed with a cDNA for the calcium-sensitive luminescent protein, aequorin, we have shown touch and wind signals to immediately increase cytosol calcium. Touch and wind

Anthony Trewavas; Marc Knight

1994-01-01

345

Calcium channel blockers and dementia  

PubMed Central

Degenerative dementia is mainly caused by Alzheimer's disease and/or cerebrovascular abnormalities. Disturbance of the intracellular calcium homeostasis is central to the pathophysiology of neurodegeneration. In Alzheimer's disease, enhanced calcium load may be brought about by extracellular accumulation of amyloid-?. Recent studies suggest that soluble forms facilitate influx through calcium-conducting ion channels in the plasma membrane, leading to excitotoxic neurodegeneration. Calcium channel blockade attenuates amyloid-?-induced neuronal decline in vitro and is neuroprotective in animal models. Vascular dementia, on the other hand, is caused by cerebral hypoperfusion and may benefit from calcium channel blockade due to relaxation of the cerebral vasculature. Several calcium channel blockers have been tested in clinical trials of dementia and the outcome is heterogeneous. Nimodipine as well as nilvadipine prevent cognitive decline in some trials, whereas other calcium channel blockers failed. In trials with a positive outcome, BP reduction did not seem to play a role in preventing dementia, indicating a direct protecting effect on neurons. An optimization of calcium channel blockers for the treatment of dementia may involve an increase of selectivity for presynaptic calcium channels and an improvement of the affinity to the inactivated state. Novel low molecular weight compounds suitable for proof-of-concept studies are now available. PMID:23638877

Nimmrich, V; Eckert, A

2013-01-01

346

Except for the noble gases, all the elements in the Periodic Table form chlorides, often in several oxidation states, and chlorides generally are among the  

E-print Network

Chlorides Except for the noble gases, all the elements in the Periodic Table form chlorides, often of the elements: for chlorides of transition metals, elevated temperatures are usually necessary in dry conditions Most chlorides are soluble in water. Mercury(I) chloride, Hg2Cl2, silver chloride, AgCl, lead chloride

Csonka, Gábor István

347

A study of the uptake of copper ions by nanostructured calcium silicate  

Microsoft Academic Search

Presented is a study of the removal of copper ions from dilute aqueous solutions by nanostructured calcium silicate. Two different copper sources, copper nitrate and copper chloride, at various concentrations ranging from 10 to 5000mgkg?1 copper have been investigated. The uptake of copper ions from aqueous solutions at concentrations below 500mgkg?1 is 97% and higher within 30min at silicate loadings

Mathew J. Cairns; Thomas Borrmann; Wolfgang H. Höll; James H. Johnston

2006-01-01

348

29 CFR 1910.1017 - Vinyl chloride.  

Code of Federal Regulations, 2010 CFR

...with legible signs bearing the legend: Cancer-Suspect Agent Area Authorized Personnel...with legible signs bearing the legend: Cancer-Suspect Agent in This Area Protective... Contaminated With Vinyl Chloride Cancer-Suspect Agent (4) Containers...

2010-07-01

349

Reductive Dechlorination of the Vinyl Chloride Surrogate  

E-print Network

by the plastics industry to produce poly(vinyl chloride) (PVC) and copolymers. In 1995, the U.S. production of VC with PVC manufacturing. In addition, accumulation of VC, a known carcinogen (2), is sometimes observed

Semprini, Lewis

350

Qualitative Determination of Nitrate with Triphenylbenzylphosphonium Chloride.  

ERIC Educational Resources Information Center

Discusses two procedures for the identification of nitrate, the standard test ("Brown Ring" test) and a new procedure using triphenylbenzylphosphonium chloride (TPBPC). Effectiveness of both procedures is compared, with the TPBPC test proving to be more sensitive and accurate. (JM)

Berry, Donna A.; Cole, Jerry J.

1984-01-01

351

21 CFR 184.1426 - Magnesium chloride.  

Code of Federal Regulations, 2010 CFR

...crystallizing out magnesium chloride hexahydrate. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 177, which is incorporated by reference. Copies are available from the National Academy Press,...

2010-04-01

352

75 FR 39025 - Determination That ACTONEL (Risendronate Sodium) Tablets, 75 Milligrams, and ACTONEL WITH CALCIUM...  

Federal Register 2010, 2011, 2012, 2013

...CALCIUM (Risendronate Sodium and Calcium Carbonate (Copackaged)) Tablets, 35...CALCIUM (risendronate sodium and calcium carbonate (copackaged)) Tablets, 35...CALCIUM (risendronate sodium and calcium carbonate (copackaged)) Tablets,...

2010-07-07

353

The oxidation of calcium sulphite by calcium nitrate  

Microsoft Academic Search

Crushed powder mixtures of calcium sulphite and calcium nitrate exhibit an exothermic reaction between 650 and 700K. This rate process has been investigated by dynamic and isothermal DSC experiments, complemented with isothermal rate studies based on gas evolution in a vacuum apparatus, together with some product analyses. It is concluded that the overall reaction is complicated, including several concurrent contributing

Andrew K Galwey; Clodagh Ettarh

1998-01-01

354

Thermally Triggered Calcium Phosphate Formation from Calcium-Loaded Liposomes  

E-print Network

Thermally Triggered Calcium Phosphate Formation from Calcium-Loaded Liposomes Phillip B 15, 1997X A thermally triggered liposome-based mineralization system is described that is metastable liposome suspension whose bulk ionic concentration was highly supersaturated with respect to hydroxyapatite

355

Preparation of Calcium-Loaded Liposomes and Their Use in Calcium Phosphate Formation  

E-print Network

Preparation of Calcium-Loaded Liposomes and Their Use in Calcium Phosphate Formation Phillip B Received October 15, 1997X Liposome encapsulation technology has been used to entrap aqueous calcium salts of unencapsulated calcium by ion exchange resulted in calcium-loaded liposome suspensions with calcium concentration

356

Growth characteristics of selected fungi on polyvinyl chloride film.  

PubMed Central

The objective of this study was to determine if plasticized polyvinyl chloride film would support the growth of any of nine species of fungi. The film was suspended in distilled water with no nutrients or with glucose or ammonium sulfate. Spores of each of the test species were inoculated into the suspension medium, and the mixture was incubated at 30 degrees C for up to 18 weeks. Most species were found to be capable of utilizing the film for carbon or nitrogen when the other nutrient was supplied. Only two species, Aspergillus fischeri and Paecilomyces sp., were found to be capable of utilizing components of the film without added nutrients. Components of the polyvinyl chloride film were then incorporated into mineral salts medium to determine if these components could serve as carbon sources in the presence of ammonium nitrate. The only component found to be utilized by all the fungi as a carbon source was epoxidized oil, a plasticizer-stabilizer. Calcium-zinc stearate was an available carbon source for all except the Penicillium and Verticillium strains. The only other component utilized was a stearamide, which was metabolized solely by the Aspergillus sp. Only the stearamide contained enough nitrogen to serve as a primary source in the film. The compound, however, did not support growth of fungi in the presence of glucose. It was theorized that either the nitrogen of the stearamide was more readily available to the fungi in the whole film due to the presence of trace nutrients or the nitrogen was supplied by exogenous sources. PMID:3707118

Roberts, W T; Davidson, P M

1986-01-01

357

The 5-(4-Ethynylophenoxy) isophthalic chloride  

NASA Technical Reports Server (NTRS)

Sulfone-ester polymers containing pendent ethynyl groups and a direct and multistep process for preparing them are disclosed. The multistep process involves the conversion of a pendent bromo group to the ethynyl group while the direct route involves reating hydroxy-terminated sulfone oligomer or polymers with a stoichiometric amount of 5-(4-ethynylphenoxy) isophthaloyl chloride. The 5-(4-ethynylphenoxy) isophthaloyl chloride and the process for preparing it are also disclosed.

Hergenrother, P. M.; Jensen, B. J. (inventors)

1986-01-01

358

Reaction of Sulfur Chlorides with Metal ?-Diketonates  

Microsoft Academic Search

Metal ß-diketonates react with sulfur dichloride to form sulfenyl chlorides irrespective of ß-substituent. Bulky phenyl and tert-butyl groups do not prevent formation of fully substituted complexes. The possibility of preparing sulfenyl chloride derivatives of rhodium, ruthenium, and vanadium ß-diketonates was demonstrated. A new procedure was suggested for preparing chlorosulfenyl-substituted ß-diketonates. Disulfur dichloride reacts with metal chelates with the substitution of

I. V. Svistunova; N. P. Shapkin; O. V. Nikolaeva

2005-01-01

359

Methyl chloride via oxhydrochlorination of methane  

SciTech Connect

Dow Corning is developing a route from methane to methyl chloride via oxyhydrochlorination (OHC) chemistry with joint support from the Gas Research Institute and the Department of Energy Federal Energy Technology Center. Dow Corning is the world`s largest producer of methyl chloride and uses it as an intermediate in the production of silicone materials. Other uses include production of higher hydrocarbons, methyl cellulose, quaternary ammonium salts and herbicides. The objective of this project is to demonstrate and develop a route to methyl chloride with reduced variable cost by using methane instead of methanol raw materials. Methyl chloride is currently produced from methanol, but U.S. demand is typically higher than available domestic supply, resulting in fluctuating prices. OHC technology utilizes domestic natural gas as a feedstock, which allows a lower-cost source of methyl chloride which is independent of methanol. In addition to other uses of methyl chloride, OHC could be a key step in a gas-to-liquid fuels process. These uses could divert significant methanol demand to methane. A stable and selective catalyst has been developed in the laboratory and evaluated in a purpose-built demonstration unit. Materials of construction issues have been resolved and the unit has been run under a range of conditions to evaluate catalyst performance and stability. Many technological advances have been made, especially in the areas of catalyst development, online FTIR analysis of the product stream, and recovery of methyl chloride product via an absorber/stripper system. Significant technological hurdles still remain including heat transfer, catalysts scaleup, orthogonality in modeling, and scaleable absorption data. Economics of the oxyhydrochlorination process have been evaluated an found to be unfavorable due to high capital and utility costs. Future efforts will focus on improved methane conversion at high methyl chloride selectivity.

Jarvis, R.F. Jr.

1997-12-31

360

Copper chloride cathode for a secondary battery  

NASA Technical Reports Server (NTRS)

Higher energy and power densities are achieved in a secondary battery based on molten sodium and a solid, ceramic separator such as a beta alumina and a molten catholyte such as sodium tetrachloroaluminate and a copper chloride cathode. The higher cell voltage of copper chloride provides higher energy densities and the higher power density results from increased conductivity resulting from formation of copper as discharge proceeds.

Bugga, Ratnakumar V. (inventor); Distefano, Salvador (inventor); Nagasubramanian, Ganesan (inventor); Bankston, Clyde P. (inventor)

1990-01-01

361

The Aspergillus giganteus antifungal protein AFPNN5353 activates the cell wall integrity pathway and perturbs calcium homeostasis  

PubMed Central

Background The antifungal protein AFPNN5353 is a defensin-like protein of Aspergillus giganteus. It belongs to a group of secretory proteins with low molecular mass, cationic character and a high content of cysteine residues. The protein inhibits the germination and growth of filamentous ascomycetes, including important human and plant pathogens and the model organsims Aspergillus nidulans and Aspergillus niger. Results We determined an AFPNN5353 hypersensitive phenotype of non-functional A. nidulans mutants in the protein kinase C (Pkc)/mitogen-activated protein kinase (Mpk) signalling pathway and the induction of the ?-glucan synthase A (agsA) promoter in a transgenic A. niger strain which point at the activation of the cell wall integrity pathway (CWIP) and the remodelling of the cell wall in response to AFPNN5353. The activation of the CWIP by AFPNN5353, however, operates independently from RhoA which is the central regulator of CWIP signal transduction in fungi. Furthermore, we provide evidence that calcium (Ca2+) signalling plays an important role in the mechanistic function of this antifungal protein. AFPNN5353 increased about 2-fold the cytosolic free Ca2+ ([Ca2+]c) of a transgenic A. niger strain expressing codon optimized aequorin. Supplementation of the growth medium with CaCl2 counteracted AFPNN5353 toxicity, ameliorated the perturbation of the [Ca2+]c resting level and prevented protein uptake into Aspergillus sp. cells. Conclusions The present study contributes new insights into the molecular mechanisms of action of the A. giganteus antifungal protein AFPNN5353. We identified its antifungal activity, initiated the investigation of pathways that determine protein toxicity, namely the CWIP and the Ca2+ signalling cascade, and studied in detail the cellular uptake mechanism in sensitive target fungi. This knowledge contributes to define new potential targets for the development of novel antifungal strategies to prevent and combat infections of filamentous fungi which have severe negative impact in medicine and agriculture. PMID:21943024

2011-01-01

362

Structure of complexes between aluminum chloride and other chlorides, 2: Alkali-(chloroaluminates). Gaseous complexes  

NASA Technical Reports Server (NTRS)

The structural chemistry of complexes between aluminum chloride and other metal chlorides is important both for practice and theory. Condensed-phase as well as vapor-phase complexes are of interest. Structural information on such complexes is reviewed. The first emphasis is given to the molten state because of its practical importance. Aluminum chloride forms volatile complexes with other metal chlorides and these vapor-phase complexes are dealt with in the second part. Finally, the variations in molecular shape and geometrical parameters are summarized.

Hargittai, M.

1980-01-01

363

Abnormal passive chloride absorption in cystic fibrosis jejunum functionally opposes the classic chloride secretory defect  

PubMed Central

Due to genetic defects in apical membrane chloride channels, the cystic fibrosis (CF) intestine does not secrete chloride normally. Depressed chloride secretion leaves CF intestinal absorptive processes unopposed, which results in net fluid hyperabsorption, dehydration of intestinal contents, and a propensity to inspissated intestinal obstruction. This theory is based primarily on in vitro studies of jejunal mucosa. To determine if CF patients actually hyperabsorb fluid in vivo, we measured electrolyte and water absorption during steady-state perfusion of the jejunum. As expected, chloride secretion was abnormally low in CF, but surprisingly, there was no net hyperabsorption of sodium or water during perfusion of a balanced electrolyte solution. This suggested that fluid absorption processes are reduced in CF jejunum, and further studies revealed that this was due to a marked depression of passive chloride absorption. Although Na+-glucose cotransport was normal in the CF jejunum, absence of passive chloride absorption completely blocked glucose-stimulated net sodium absorption and reduced glucose-stimulated water absorption 66%. This chloride absorptive abnormality acts in physiological opposition to the classic chloride secretory defect in the CF intestine. By increasing the fluidity of intraluminal contents, absence of passive chloride absorption may reduce the incidence and severity of intestinal disease in patients with CF. PMID:12840066

Russo, Michael A.; Hogenauer, Christoph; Coates, Stephen W.; Santa Ana, Carol A.; Porter, Jack L.; Rosenblatt, Randall L.; Emmett, Michael; Fordtran, John S.

2003-01-01

364

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2012 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2012-04-01

365

CALCIUM CARBONATE DEPOSITION IN GEOTHERMAL WELLBORES  

E-print Network

CALCIUM CARBONATE DEPOSITION IN GEOTHERMAL WELLBORES MIRAVALLES GEOTHERMAL FIELD COSTA RICA CALCIUM CARBONATE DEPOSITION IN GEOTHERMAL WELLBORES MIRAVALLES GEOTHERMAL FIELD COSTA RICA BY Eduardo University. #12;ABSTRACT Calcium carbonate deposition takes place in the wells of the Miravalles geothermal

Stanford University

366

21 CFR 184.1210 - Calcium oxide.  

Code of Federal Regulations, 2013 CFR

...Substances Affirmed as GRAS § 184.1210 Calcium oxide. (a) Calcium oxide (CaO, CAS Reg. No. 1305-78-8...lime, burnt lime, or calx. It is produced from calcium carbonate, limestone, or oyster shells by...

2013-04-01

367

21 CFR 184.1201 - Calcium glycerophosphate.  

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2014-04-01

368

21 CFR 184.1210 - Calcium oxide.  

...Specific Substances Affirmed as GRAS § 184.1210 Calcium oxide. (a) Calcium oxide (CaO, CAS Reg. No. 1305-78-8...lime, burnt lime, or calx. It is produced from calcium carbonate, limestone, or oyster shells by...

2014-04-01

369

21 CFR 184.1210 - Calcium oxide.  

Code of Federal Regulations, 2010 CFR

...Substances Affirmed as GRAS § 184.1210 Calcium oxide. (a) Calcium oxide (CaO, CAS Reg. No. 1305-78-8...lime, burnt lime, or calx. It is produced from calcium carbonate, limestone, or oyster shells by...

2010-04-01

370

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2011 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2011-04-01

371

21 CFR 184.1210 - Calcium oxide.  

Code of Federal Regulations, 2011 CFR

...Substances Affirmed as GRAS § 184.1210 Calcium oxide. (a) Calcium oxide (CaO, CAS Reg. No. 1305-78-8...lime, burnt lime, or calx. It is produced from calcium carbonate, limestone, or oyster shells by...

2011-04-01

372

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2013 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2013-04-01

373

21 CFR 184.1201 - Calcium glycerophosphate.  

Code of Federal Regulations, 2010 CFR

...hygroscopic powder. It is prepared by neutralizing glycerophosphoric acid with calcium hydroxide or calcium carbonate. The commercial product is a mixture of calcium ?-, and D-, and L -?-glycerophosphate. (b) The...

2010-04-01

374

21 CFR 184.1210 - Calcium oxide.  

Code of Federal Regulations, 2012 CFR

...Substances Affirmed as GRAS § 184.1210 Calcium oxide. (a) Calcium oxide (CaO, CAS Reg. No. 1305-78-8...lime, burnt lime, or calx. It is produced from calcium carbonate, limestone, or oyster shells by...

2012-04-01

375

21 CFR 172.720 - Calcium lactobionate.  

Code of Federal Regulations, 2011 CFR

...Calcium lactobionate. The food additive calcium lactobionate may be safely used in food in accordance with the following...conditions: (a) The food additive is the calcium...D-gluconic acid) produced by the oxidation of lactose. (b)...

2011-04-01

376

Vitamin D, Calcium, and Bone Health  

MedlinePLUS

... SITE › Vitamin D, Calcium, and Bone Health Share: Vitamin D, Calcium, and Bone Health March 2012 Download ... also helps keep your bones strong. Why are vitamin D and calcium important to bone health? Vitamin ...

377

RESEARCH ARTICLE Increasing chloride concentrations in Lake Constance  

E-print Network

for the year 2006, we estimated total chloride imports to the catchment at 101 kt year-1 . Road deicing salts Chloride Á Budget Á Road deicing salt Introduction Sodium chloride (NaCl) is used widely and in large streams, Trowbridge et al. (2010) showed that [90% of the chloride originated from road salt. Imported

Wehrli, Bernhard

378

Methylene Chloride Management Plan Review and Approval Authority  

E-print Network

Waste Management, Fire Protection, Radiation Safety, Insurance Services, Hazard Communication, AccidentMETHYLENE CHLORIDE MANAGEMENT PLAN #12;#12;Methylene Chloride Management Plan Review and Approval Date #12;ii Methylene Chloride Management Plan #12;Methylene Chloride Management Plan Table of Contents

Rubloff, Gary W.

379

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

PubMed

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

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

1969-10-01

380

Analysis of the Effects of Calcium or Magnesium on Voltage-Clamp Currents in Perfused Squid Axons Bathed in Solutions of High Potassium  

PubMed Central

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

Rojas, Eduardo; Taylor, Robert E.; Atwater, Illani; Bezanilla, Francisco

1969-01-01

381

Molecular Structure of Calcium Sulfide  

NSDL National Science Digital Library

Calcium sulfide in pure form is white and shaped like cubic crystals, and is slightly soluble in water. This is used as a base for luminescent materials. Calcium sulfide is also known as hepar calcies; sulfurated lime. This substance is used in phosphors and as a direct fungicide on powdery mildews and insecticides.

2003-06-03

382

An Improved Calcium Flame Test.  

ERIC Educational Resources Information Center

Indicates that the true red color of calcium can be obtained (using the procedure described by Sorm and Logowski) if the calcium ion solution is mixed with an equal volume of saturated ammonium bromide solution. Suggestions for flame tests of other elements are also noted. (JN)

Pearson, Robert S.

1985-01-01

383

Calcium Intake: A Lifelong Proposition.  

ERIC Educational Resources Information Center

This article reviews the current problem of low calcium intake in the United States among all age groups, the role of calcium in the formation and maintenance of bone mass, and major factors influencing absorption. Osteoporosis is discussed, and current recommendations for Recommended Dietary allowance are provided. (Author/MT)

Amschler, Denise H.

1985-01-01

384

Calcium intake and serum calcium status in Mongolian children.  

PubMed

Dietary calcium intake in relation to calcium status in Mongolian children was investigated. This survey was a cross-sectional survey. A total of 835 children were randomly selected from 4 economic regions and Ulaanbaatar city. Information on dietary intake was collected from 835 children in the 1-3, 4-7, and 8-14 year old groups by a 24-h recall method. The average daily intake of calcium from diet was calculated for individuals. Blood samples were collected from 104 children. The mean of daily calcium intakes as 273±30.0mg in 1-3-year old children, 309.0±30.0mg in 4-7 year old children, and 317.0±31.0mg in 8-14 year old children, respectively. There were statistically significant differences in calcium intakes between the age groups 1-3 years, 4-7 years, and 1-3 years, 8-14 years of children (p<0.001). Calcium intakes in all studied children of all age groups were lower (39%, 30.9%, and 24.4%) than the recommended level of calcium intakes. In 22.1% of studied children, the serum total calcium concentration levels were below the normal range. Based on the total serum calcium, the prevalence of hypocalcemia was higher among children in the age group 8-14 years (27.6%) than the prevalence among children in the age group <1 year (p<0.05). Based on the corrected serum calcium values, the prevalence of hypocalcemia was higher (52.4%, 63.6%, and 51.1%) among children in the age groups 1-3, 4-7, and 8-14 years. The mean level of corrected serum calcium were low (2.02±0.04, 2.05±0.73, and 1.99±0.64mg) in children in the age groups 1-3, 4-7, and 8-14 years. These findings suggest that low dietary calcium intakes may be reflected by hypocalcemia in Mongolian children. In conclusion, there is a need to improve a consumption of milk, dairy products in Mongolian children. In addition, there is need to use a vitamin D supplementation with a calcium supplementation in children with severe vitamin D deficiency rickets. This article is part of a Special issue entitled "16th Vitamin D Workshop". PMID:24681400

Uush, Tserendolgor

2014-10-01

385

Localization and functional characterization of rat kidney-specific chloride channel, ClC-K1.  

PubMed Central

To investigate the physiological role of a kidney-specific chloride channel (ClC-K1), we sought to determine its exact localization by immunohistochemistry and its functional regulation using Xenopus oocyte expression system. The antiserum specifically recognized a 70-kD protein in SDS-PAGE of membrane protein from rat inner medulla and an in vitro translated ClC-K1 protein. Immunohistochemistry revealed that ClC-K1 was exclusively localized to the thin limb of Henle's loop in rat inner medulla. In comparison with the immunostaining with anti-aquaporin-CHIP antibody that only stains the descending thin limb of Henle's loop (tDL), ClC-K1 was found to be localized only in the ascending limb (tAL) which has the highest chloride permeability among nephron segments. Immunoelectron microscopy confirmed that the staining of ClC-K1 in tAL was observed in the region of both apical and basolateral plasma membranes. Expressed chloride current in Xenopus oocytes by ClC-K1 cRNA was regulated by extracellular pH and extracellular calcium. Furosemide inhibited the expressed current (Ki = 100 microM), whereas N-ethyl-maleimide stimulated the current. These functional characteristics were consistent with the in vitro perfusion studies of chloride transport in tAL. The localization and the functional characteristics described here indicate that ClC-K1 is responsible for the transepithelial chloride transport in tAL. Images PMID:7814604

Uchida, S; Sasaki, S; Nitta, K; Uchida, K; Horita, S; Nihei, H; Marumo, F

1995-01-01

386

Calcium-sensing receptor and calcium kidney stones  

PubMed Central

Calcium nephrolithiasis may be considered as a complex disease having multiple pathogenetic mechanisms and characterized by various clinical manifestations. Both genetic and environmental factors may increase susceptibility to calcium stones; therefore, it is crucial to characterize the patient phenotype to distinguish homogeneous groups of stone formers. Family and twin studies have shown that the stone transmission pattern is not mendelian, but complex and polygenic. In these studies, heritability of calcium stones was calculated around 50% Calcium-sensing receptor (CaSR) is mostly expressed in the parathyroid glands and in renal tubules. It regulates the PTH secretion according to the serum calcium concentration. In the kidney, it modulates electrolyte and water excretion regulating the function of different tubular segments. In particular, CaSR reduces passive and active calcium reabsorption in distal tubules, increases phosphate reabsorption in proximal tubules and stimulates proton and water excretion in collecting ducts. Therefore, it is a candidate gene for calcium nephrolithiasis. In a case-control study we found an association between the normocitraturic stone formers and two SNPs of CaSR, located near the promoters region (rs7652589 and rs1501899). This result was replicated in patients with primary hyperparathyroidism, comparing patients with or without kidney stones. Bioinformatic analysis suggested that the minor alleles at these polymorphisms were able to modify the binding sites of specific transcription factors and, consequently, CaSR expression. Our studies suggest that CaSR is one of the candidate genes explaining individual predisposition to calcium nephrolithiasis. Stone formation may be favored by an altered CaSR expression in kidney medulla involving the normal balance among calcium, phosphate, protons and water excretion. PMID:22107799

2011-01-01

387

Absorption and transfer of light and photoreduction activities of spinach chloroplasts under calcium deficiency: promotion by cerium.  

PubMed

Chloroplasts were isolated from spinach cultured in calcium-deficient, cerium-chloride-administered calcium-present Hoagland's media or that of calcium-deficient Hoagland's media and demonstrated the effects of cerium on distribution of light energy between photosystems II and I and photochemical activities of spinach chloroplast grown in calcium-deficient media. It was observed that calcium deprivation significantly inhibited light absorption, energy transfer from LHCII to photosystemII, excitation energy distribution from PSI to PSII, and transformation from light energy to electron energy and oxygen evolution of chloroplasts. However, cerium treatment to calcium-deficient chloroplasts could obviously improve light absorption and excitation energy distribution from photosystem I to photosystem II and increase activity of whole chain electron transport, photosystems II and I DCPIP photoreduction, and oxygen evolution of chloroplasts. The results suggested that cerium under calcium deficiency condition could substitute for calcium in chloroplasts, maintain the stability of chloroplast membrane, and improve photosynthesis of spinach chloroplast, but the mechanisms still need further study. PMID:18193396

Hao, Huang; Ling, Chen; Xiaoqing, Liu; Chao, Liu; Weiqian, Cao; Yun, Lu; Fashui, Hong

2008-05-01

388

Renal calcium and magnesium excretion during vasopressin administration into sheep with acid or alkaline urine.  

PubMed Central

1. The proposition that changes in renal calcium excretion during vasopressin administration are positively correlated with concurrent changes in urine hydrogen ion concentration was tested by administration of vasopressin into twelve conscious diuresing sheep receiving either alkalinizing or acidifying infusions. 2. Vasopressin-induced antidiuresis in sheep with alkaline urine was associated with significant increases in urinary pH and decreases in the rate of calcium excretion whereas antidiuresis in sheep with acid urine was associated with significant decreases in urinary pH and no consistent effect on calcium excretion. 3. Magnesium excretion increased during vasopressin administration in most experiments regardless of urinary pH changes. 4. Vasopressin administration did not significantly alter the rate of excretion of sodium, potassium, chloride and phosphate or the rates of sodium, potassium, chloride, inulin, para-aminohippurate and osmolal clearance in sheep with either acid or alkaline urine. Potassium excretion and clearance in sheep with alkaline ruine was higher than that of sheep with acid urine during vasopressin infusion. 5. The results support the hypothesis that changes in renal tubular hydrogen ion concentration or bicarbonate concentration caused by water reabsorption from the collecting duct and possibly the late distal tubule could be part of the explanation for changes in renal calcium excretion which occur during vasopressin-induced antidiuresis. PMID:41939

Beal, A M

1979-01-01

389

The relative importance of water hardness and chloride levels in modifying the acute toxicity of silver to rainbow trout (Oncorhynchus mykiss)  

SciTech Connect

Static-renewal 7-d toxicity tests for silver nitrate (AgNO{sub 3}) were performed with juvenile rainbow trout (Oncorhynchus mykiss Walbaum). The relative influences of calcium and chloride concentrations on median lethal time (LT50) were assessed. For both calcium salts, a 100-fold elevation in concentration increased the LT50 approximately 10-fold. However, a 100-fold elevation in KCl ameliorated silver (Ag) toxicity at least 100-fold, while NaCl protected against Ag toxicity even more substantially, demonstrating the much greater protective effect of chloride relative to calcium. In a separate series of bioassays, fish were exposed to 0.92 {micro}M Ag with varying amounts of NaCl titrated into each tank to alter the free [Ag{sup +}]. The 7-d LC50 occurred at a [NaCl] of 2,500 {micro}M. Using MINEQL{sup +}, the predicted free [Ag{sup +}] at this LC50 value is 0.0285 {micro}M. Further bioassays were performed in which [chloride] was maintained at either 50 or 225 {micro}M, while total [Ag] was independently varied from 0.0092 to 0.0694 {micro}M (1.0--7.5 {micro}g/L). The 7-d LC50 value was calculated at 0.0294 {micro}M Ag (3.18 {micro}g/L) at a chloride concentration of 50 {micro}M, very similar to the free [Ag{sup +}] value of 0.031 {micro}M calculated from an earlier LC50 test at a fixed [chloride] of 730 {micro}M. Elevating chloride concentrations from 50 to 225 {micro}M did not alter the accumulation of Ag in the liver. In addition, there were no significant differences in hepatic Ag accumulation between any of the Ag-exposed fish, irrespective of the total Ag concentration used during the exposure.

Galvez, F.; Wood, C.M. [McMaster Univ., Hamilton, Ontario (Canada). Dept. of Biology

1997-11-01

390

Thermoluminescence of ultra-high dilutions of lithium chloride and sodium chloride  

Microsoft Academic Search

Ultra-high dilutions of lithium chloride and sodium chloride (10?30gcm?3) have been irradiated by X- and ?-rays at 77K, then progressively rewarmed to room temperature. During that phase, their thermoluminescence has been studied and it was found that, despite their dilution beyond the Avogadro number, the emitted light was specific of the original salts dissolved initially.

Louis Rey

2003-01-01

391

Study of chloridizing volatilization roasting of cinnabar as a basis for a process to obtain mercuric and mercurous chlorides  

Microsoft Academic Search

This paper presents a study of the chloridizing volatilization reaction of concentrated cinnabar ore from Almadén, Spain in\\u000a an air atmosphere in order to obtain mercuric and mercurous chlorides in a single step. The chloridizing agents used were\\u000a ferric or aluminum chloride 6-hydrates. These chlorides decompose to HC1 at temperatures lower than required to break down\\u000a cinnabar. According to the

A. Roca; M. Cruells; C. Núñez

1990-01-01

392

Mechanism for forming hydrogen chloride and sodium sulfate from sulfur trioxide, water, and sodium chloride  

NASA Technical Reports Server (NTRS)

A molecular orbital study of sodium sulfate and hydrogen chloride formation from sulfur trioxide, water, and sodium chloride shows no activation barrier, in agreement with recent experimental work of Kohl, Fielder, and Stearns. Two overall steps are found for the process. First, gas-phase water reacts with sulfur trioxide along a pathway involving a linear O-H-O transition state yielding closely associated hydroxyl and bisulfite which rearrange to become a hydrogen sulfate molecule. Then the hydrogen sulfate molecule transfers a hydrogen atom to a surface chloride in solid sodium chloride while an electron and a sodium cation simultaneously transfer to yield sodium bisulfate and gas-phase hydrogen chloride. This process repeats. Both of these steps represent well-known reactions for which mechanisms have not been previously determined.

Anderson, A. B.

1984-01-01

393

Mechanism for forming hydrogen chloride and sodium sulfate from sulfur trioxide, water, and sodium chloride  

SciTech Connect

A molecular orbital study of sodium sulfate and hydrogen chloride formation from sulfur trioxide, water, and sodium chloride shows no activation barrier, in agreement with recent experimental work of Kohl, Fielder, and Stearns. Two overall steps are found for the process. First, gas-phase water reacts with sulfur trioxide along a pathway involving a linear O...H...O transition state yielding closely associated hydroxyl and bisulfite which rearrange to become a hydrogen sulfate molecule. Then the hydrogen sulfate molecule transfers a hydrogen atom to a surface chloride in solid sodium chloride while an electron and a sodium cation simultaneously transfer to yield sodium bisulfate and gas-phase hydrogen chloride. This process repeats. Both of these steps represent well-known reactions for which mechanisms have not been previously determined.

Anderson, A.B.

1984-10-17

394

Calcium binding protein-mediated regulation of voltage-gated calcium channels linked to human diseases  

Microsoft Academic Search

Calcium ion entry through voltage-gated calcium channels is essential for cellular signalling in a wide variety of cells and multiple physiological processes. Perturbations of voltage-gated calcium channel function can lead to pathophysiological consequences. Calcium binding proteins serve as calcium sensors and regulate the calcium channel properties via feedback mechanisms. This review highlights the current evidences of calcium binding protein-mediated channel

Nasrin Nejatbakhsh; Zhong-ping Feng

2011-01-01

395

Electrochemical chloride extraction: efficiency and side effects  

SciTech Connect

Some specimens of reinforced concrete cast with an alkali-resistant aggregate, previously maintained in a solution of NaCl, were subjected to an electrochemical chloride extraction (ECE). The chloride profiles before and after treatment were determined. Likewise, alkali ions profiles before and after treatment were determined. After treatment, some specimens were stored in a controlled atmosphere (60 deg. C and 100% RH) in order to accelerate the alkali-silica reaction, if any. Results of chloride content after treatment show that about 40% of the initial chloride is removed within 7 weeks. About one-half of the chloride close to steel was removed, but at the same time, significant amounts of alkali ions were observed around the steel. Microstructural observations by scanning electron microscopy (SEM) showed that after treatment, new cementitious phases containing higher concentrations of sodium, aluminum and potassium were formed. Moreover, alkali-silica gel was observed in the specimens stored at 60 deg. C and 100% RH. It may be possible that the ECE accumulates locally high amounts of alkali ions that stimulate the alkali-silica reaction even though the concrete contained nominally inert siliceous aggregates. The specimen expansions were not recorded, but no cracks were observed.

Orellan, J.C.; Escadeillas, G.; Arliguie, G

2004-02-01

396

Advanced intermediate temperature sodium copper chloride battery  

NASA Astrophysics Data System (ADS)

Sodium metal chloride batteries, also called as ZEBRA batteries, possess many merits such as low cost, high energy density and high safety, but their high operation temperature (270-350 °C) may cause several issues and limit their applications. Therefore, decreasing the operation temperature is of great importance in order to broaden their usage. Using a room temperature ionic liquid (RTIL) catholyte composed of sodium chloride buffered 1-ethyl-3-methylimidazolium chloride-aluminum chloride and a dense ??-aluminates solid electrolyte film with 500 micron thickness, we report an intermediate temperature sodium copper chloride battery which can be operated at only 150 °C, therefore alleviating the corrosion issues, improving the material compatibilities and reducing the operating complexities associated with the conventional ZEBRA batteries. The RTIL presents a high ionic conductivity (0.247 S cm-1) at 150 °C and a wide electrochemical window (-2.6 to 2.18 vs. Al3+/Al). With the discharge plateau at 2.64 V toward sodium and the specific capacity of 285 mAh g-1, this intermediate temperature battery exhibits an energy density (750 mWh g-1) comparable to the conventional ZEBRA batteries (728-785 mWh g-1) and superior to commercialized Li-ion batteries (550-680 mWh g-1), making it very attractive for renewable energy integration and other grid related applications.

Yang, Li-Ping; Liu, Xiao-Min; Zhang, Yi-Wei; Yang, Hui; Shen, Xiao-Dong

2014-12-01

397

Quantitative estimation of carbonation and chloride penetration in reinforced concrete by laser-induced breakdown spectroscopy  

NASA Astrophysics Data System (ADS)

The penetration profile of chlorine in a reinforced concrete (RC) specimen was determined by laser-induced breakdown spectroscopy (LIBS). The concrete core was prepared from RC beams with cracking damage induced by bending load and salt water spraying. LIBS was performed using a specimen that was obtained by splitting the concrete core, and the line scan of laser pulses gave the two-dimensional emission intensity profiles of 100 × 80 mm2 within one hour. The two-dimensional profile of the emission intensity suggests that the presence of the crack had less effect on the emission intensity when the measurement interval was larger than the crack width. The chlorine emission spectrum was measured without using the buffer gas, which is usually used for chlorine measurement, by collinear double-pulse LIBS. The apparent diffusion coefficient, which is one of the most important parameters for chloride penetration in concrete, was estimated using the depth profile of chlorine emission intensity and Fick's law. The carbonation depth was estimated on the basis of the relationship between carbon and calcium emission intensities. When the carbon emission intensity was statistically higher than the calcium emission intensity at the measurement point, we determined that the point was carbonated. The estimation results were consistent with the spraying test results using phenolphthalein solution. These results suggest that the quantitative estimation by LIBS of carbonation depth and chloride penetration can be performed simultaneously.

Eto, Shuzo; Matsuo, Toyofumi; Matsumura, Takuro; Fujii, Takashi; Tanaka, Masayoshi Y.

2014-11-01

398

Articles Lead in Calcium Supplements  

E-print Network

Intercalibrated measurements of lead in calcium supplements indicate the importance of rigorous analytical techniques to accurately quantify contaminant exposures in complex matrices. Without such techniques, measurements of lead concentrations in calcium supplements may be either erroneously low, by as much as 50%, or below the detection limit needed for new public health criteria. In this study, we determined the lead content of 136 brands of supplements that were purchased in 1996. The calcium in the products was derived from natural sources (bonemeal, dolomite, or oyster shell) or was synthesized and/or refined (chelated and nonchelated calcium). The dried products were acid digested and analyzed for lead by high resolution-inductively coupled plasma-mass spectrometry. The method’s limit of quantitation averaged 0.06 µg/g, with a coefficient of variation of 1.7 % and a 90–100 % lead recovery of a bonemeal standard reference material. Two-thirds of those calcium supplements failed to meet the 1999 California criteria for acceptable lead levels (1.5 µg/daily dose of calcium) in consumer products. The nonchelated synthesized and/or refined calcium products, specifically antacids and infant formulas, had the lowest lead concentrations, ranging from nondetectable to 2.9 µg Pb/g calcium, and had the largest proportion of brands meeting the new criteria (85 % of the antacids and 100 % of the infant formulas). Key words: antacids, bonemeal, calcium supplements, dolomite, inductively coupled plasma-mass spectrometry (ICP-MS), infant formulas, lead, nutritional supplements, oyster shell, vitamins. Environ Health Perspect 108:309–313 (2000). [Online 21 February 2000

Genine M. Scelfo; A. Russell Flegal

399

Calcium carbonate and calcium sulfate in Martian meteorite EETA79001  

NASA Technical Reports Server (NTRS)

Chips of glassy Lithology C of EETA79001 were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy to determine the mineralogy and petrogenesis of the glass that was shown by others to contain trapped Mars-like gases. Calcium carbonite was identified as massive to acicular crystals for which Ca, C, and O were the major elements. Calcium sulfate was identified as prismatic-acicular crystals with Ca and S as the major elements.

Gooding, J. L.; Wentworth, S. J.

1987-01-01

400

Influence of dietary calcium on bone calcium utilization  

SciTech Connect

In Experiment 1, 10 microCi /sup 45/Ca/day were administered to 125 hens for 10 days. Hens were then allocated to five treatments with calcium levels ranging from .08 to 3.75% of the diet. In Experiment 2, hens with morning oviposition times were randomly allocated to 11 treatments that were periods of time postoviposition ranging from 6 hr to 24 hr, in 2-hr increments (Experiment 2). At the end of each 2-hr period, eggs from 25 hens were removed from the uterus. The 18-, 20-, and 22-hr treatments were replicated three times. In Experiment 3, hens were fed either ad libitum or feed was withheld the last 5 or 6 hr before oviposition. In Experiment 4, hens were fed 10 microCi of /sup 45/Ca for 15 days to label skeletal calcium. Hens were divided into two groups and fed a .08 or 3.75% calcium diet for 2 days. On the second day, 25 hens fed the 3.75% calcium diet were intubated with 7 g of the same diet containing .5 g calcium at 1700, 2100, 0100, 0500, and 0700 hr. The measurements used were egg weight, shell weight, and /sup 45/Ca content of the egg shell. Results indicated a significant linear or quadratic regression of dietary calcium levels on /sup 45/Ca accumulation in eggshells and eggshell weight (Experiment 1). As the calcium level of the diet increased, eggshell weight increased and /sup 45/Ca recovery decreased. Utilization of skeletal calcium for shell formation ranged from 28 to 96%. In Experiment 2, the rate of shell calcification was not constant throughout the calcification process but varied significantly.

Farmer, M.; Roland, D.A. Sr.; Clark, A.J.

1986-02-01

401

A transient calcium-dependent chloride current in the immature Xenopus oocyte.  

PubMed Central

Ionic currents were studied in immature full-grown Xenopus oocytes using the two-micro-electrode voltage-clamp technique. Recordings of total membrane current showed a transient outward peak during depolarizations from the approximate resting voltage (-70 or -80 mV) to voltages more positive than -20 mV. The current-voltage relation for peak outward current was U-shaped, with a maximum at about 0 mV. Replacement of external Cl with methanesulphonate reversed this transient outward current to a transient inward current. Current relaxations recorded after the membrane potential was stepped to different voltages at the time of the peak showed a component that inverted at about -25 to -30 mV. This value was close to ECl as determined by measurement of the intracellular Cl ion concentration. The reversal potential for these current relaxations changed with the external Cl concentration as predicted by the Nernst relation. Replacement of external Ca with Mg, Sr or Ba, or addition of low concentrations of Ni in the presence of Ca, eliminated the transient outward current. Increasing the external Ca concentration increased the amplitude of the transient outward current without affecting the amplitude of the steady-state current. It was concluded that the outward peak in records of total membrane current represented the contribution of a transient outward current carried by Cl ions which was dependent on the entry of external Ca. It will be noted as ICl(Ca). Decay of ICl(Ca) could be described at the normal Ca concentration by a single exponential function whose time constant showed a shallow U-shaped voltage dependence. ICl(Ca) was maximally activatable by depolarizations from a holding potential of about -100 mV, but could not be activated by depolarizations from -40 mV. The amplitude of ICl(Ca) showed a large temperature dependence as compared to the steady-state current, suggesting complex control of its activation. PMID:6313909

Barish, M E

1983-01-01

402

and precipitation of the supernatant with a mixture of alginic acid and calcium chloride.  

E-print Network

heated at moderate temperature (PLH). Food intake was determined every other day and body weight diet for 10 days and finally the WL diet for 10 days. Food intake level was measured every 2 days modification of food intake. With the young rats, the duration of the feeding period did not influence the mean

Paris-Sud XI, Université de

403

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

E-print Network

(Fenn and Kissel, 1973). Ammonia exiting the soil chainber with the air-flow was captured in a boric acid indicator trap containing 40 mL of boric acid indicator solution. The boric acid indicator traps were changed every 24 h and titrated... of the air-flow through the remaining flasks was increased to 95 to 100% by replacing the concentrated HzSO4 with distilled water. As soon as NHs volatilization resumed, as indicated by the boric acid indicator solution, a soil flask was removed from each...

Sloan, John J.

2012-06-07

404

Calcium-dependent chloride conductance in epithelia: is there a contribution by Bestrophin?  

Microsoft Academic Search

Although known for more than 20 years, the molecular identity of epithelial Ca2+-activated Cl? channels remains obscure. Previous candidate proteins did not hold initial promises, and thus, new hope is put into the recently\\u000a identified family of bestrophin proteins, as they reflect many of the properties found for native channels. Mutations in the\\u000a bestrophin gene cause an autosomal form of macular

Karl Kunzelmann; Vladimir M. Milenkovic; Melanie Spitzner; René Barro Soria; Rainer Schreiber

2007-01-01

405

Direct electrochemical reduction of titanium dioxide to titanium in molten calcium chloride  

NASA Astrophysics Data System (ADS)

Many reactive metals are difficult to prepare in pure form without complicated and expensive procedures. Although titanium has many desirable properties (it is light, strong and corrosion-resistant), its use has been restricted because of its high processing cost. In the current pyrometallurgical process-the Kroll process-the titanium minerals rutile and ilmenite are carbo-chlorinated to remove oxygen, iron and other impurities, producing a TiCl4 vapour. This is then reduced to titanium metal by magnesium metal; the by-product MgCl2 is removed by vacuum distillation. The prediction that this process would be replaced by an electrochemical route has not been fulfilled; attempts involving the electro-deposition of titanium from ionic solutions have been hampered by difficulties in eliminating the redox cycling of multivalent titanium ions and in handling very reactive dendritic products. Here we report an electrochemical method for the direct reduction of solid TiO2, in which the oxygen is ionized, dissolved in a molten salt and discharged at the anode, leaving pure titanium at the cathode. The simplicity and rapidity of this process compared to conventional routes should result in reduced production costs and the approach should be applicable to a wide range of metal oxides.

Chen, George Zheng; Fray, Derek J.; Farthing, Tom W.

2000-09-01

406

Channel properties of the splicing isoforms of the olfactory calcium-activated chloride channel Anoctamin 2  

PubMed Central

Anoctamin (ANO)2 (or TMEM16B) forms a cell membrane Ca2+-activated Cl? channel that is present in cilia of olfactory receptor neurons, vomeronasal microvilli, and photoreceptor synaptic terminals. Alternative splicing of Ano2 transcripts generates multiple variants with the olfactory variants skipping exon 14 and having alternative splicing of exon 4. In the present study, 5? rapid amplification of cDNA ends analysis was conducted to characterize the 5? end of olfactory Ano2 transcripts, which showed that the most abundant Ano2 transcripts in the olfactory epithelium contain a novel starting exon that encodes a translation initiation site, whereas transcripts of the publically available sequence variant, which has an alternative and longer 5? end, were present in lower abundance. With two alternative starting exons and alternative splicing of exon 4, four olfactory ANO2 isoforms are thus possible. Patch-clamp experiments in transfected HEK293T cells expressing these isoforms showed that N-terminal sequences affect Ca2+ sensitivity and that the exon 4–encoded sequence is required to form functional channels. Coexpression of the two predominant isoforms, one with and one without the exon 4 sequence, as well as coexpression of the two rarer isoforms showed alterations in channel properties, indicating that different isoforms interact with each other. Furthermore, channel properties observed from the coexpression of the predominant isoforms better recapitulated the native channel properties, suggesting that the native channel may be composed of two or more splicing isoforms acting as subunits that together shape the channel properties. PMID:23669718

Ponissery Saidu, Samsudeen; Stephan, Aaron B.; Talaga, Anna K.

2013-01-01

407

Activation of calcium-dependent chloride channels causes post-tetanic depolarization in rabbit parasympathetic neurons  

Microsoft Academic Search

Intracellular recordings were made from neurons in rabbit and feline vesical parasympathetic ganglia in vitro. In response to cathodal current injection (0.1–1 nA for 2–20 ms) the majority of rabbit neurons (229 out of 250) exhibited a single action potential that was followed by a fast and slow after-hyperpolarization (sAHP neuron). The remainder of the cells exhibited an action potential

Toshihiko Nishimura

1995-01-01

408

New optically active poly(amide–imide)s from N-trimellitylimido- l-amino acid and 1,2-bis[4-aminophenoxy]ethane in the main chain: Synthesis and characterization  

Microsoft Academic Search

Six new optically active poly(amide–imide)s (PAIs) with good inherent viscosities were synthesized from the direct polycondensation reaction of N-trimellitylimido-l-amino acids with 1,2-bis[4-aminophenoxy]ethane by direct polycondensation in a medium consisting of N-methyl-2-pyrrolidone (NMP)\\/triphenyl phosphite (TPP)\\/calcium chloride (CaCl2)\\/pyridine (py). Diamine was synthesized by using a two-step reaction. At first 1,2-bis[4-nitrophenoxy]ethane was prepared from the reaction of two equimolars 4-nitrophenol and one equimolar

Khalil Faghihi; Mehdi Nourbakhsh; Mohsen Hajibeygi

409

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2010 CFR

...as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6 H10 CaO6 .xH2 O, where...commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient...

2010-04-01

410

21 CFR 184.1207 - Calcium lactate.  

...as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6 H10 CaO6. xH2 O, where...commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient...

2014-04-01

411

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2012 CFR

...as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6 H10 CaO6 .xH2 O, where...commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient...

2012-04-01

412

INTRODUCTION Pedogenic (secondary) calcium carbonate is,  

E-print Network

INTRODUCTION Pedogenic (secondary) calcium carbonate is, by definition, a product of soil processes of calcium for pe- dogenic calcium carbonate (Gile et al., 1979). In regard to the source of the carbonate; Cerling et al., 1989; Quade et al., 1989). Because pedogenic calcium carbonate is read- ily soluble, its

Ahmad, Sajjad

413

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2013 CFR

...as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6 H10 CaO6 .xH2 O, where...commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient...

2013-04-01

414

21 CFR 184.1207 - Calcium lactate.  

Code of Federal Regulations, 2011 CFR

...as GRAS § 184.1207 Calcium lactate. (a) Calcium lactate (C6 H10 CaO6 .xH2 O, where...commercially by the neutralization of lactic acid with calcium carbonate or calcium hydroxide. (b) The ingredient...

2011-04-01

415

Hazards of lithium thionyl chloride batteries  

NASA Technical Reports Server (NTRS)

Two different topics which only relate in that they are pertinent to lithium thionyl chloride battery safety are discussed. The first topic is a hazards analysis of a system (risk assessment), a formal approach that is used in nuclear engineering, predicting oil spills, etc. It is a formalized approach for obtaining assessment of the degree of risk associated with the use of any particular system. The second topic is a small piece of chemistry related to the explosions that can occur with lithium thionyl chloride systems. After the two topics are presented, a discussion is generated among the Workshop participants.

Parry, J. M.

1978-01-01

416

Measuring Sodium Chloride Contents of Aerosols  

NASA Technical Reports Server (NTRS)

Amount of sodium chloride in individual aerosol particles measured in real time by analyzer that includes mass spectrometer. Analyzer used to determine mass distributions of active agents in therapeutic or diagnostic aerosols derived from saline solutions and in analyzing ocean spray. Aerosol particles composed of sodium chloride introduced into oven, where individually vaporized on hot wall. Vapor molecules thermally dissociated, and some of resulting sodium atoms ionized on wall. Ions leave oven in burst and analyzed by spectrometer, which is set to monitor sodium-ion intensity.

Sinha, M. P.; Friedlander, S. K.

1986-01-01

417

Continual Groundwater Monitoring with Inexpensive Chloride Sensors  

NASA Astrophysics Data System (ADS)

A simple chloride sensor technology, using an oxidized silver rod and reference electrode attached to a data logger, can be used as an inexpensive yet effective tool for the continuous measurement of chloride concentration in groundwater. The sensor is seen to be responsive at concentrations from less than 35 mg/l to 35,000 mg/l, with an error of less than 7% after the sensor is corrected for drift. When monitoring changes in groundwater salinity, the sensor has shown to be particularly useful when chloride concentrations are under 100 mg/l; at these lower salinities, conductivity probes become less responsive, whereas the chloride sensor is still able to register the smaller concentration changes. The sensor is particularly useful for continuous monitoring. Calibration and drift adjustment can be accomplished by simply taking a water sample in the beginning and at the end of the monitoring period. This allows the sensor to be adjusted for drift within the signal over the monitoring period. Occasional samples taken during the monitoring period provide control on the drift during the monitoring period. Chloride concentration from the control samples can be accurately and inexpensively calculated through titration methods, and do not need to be sent to an external laboratory for analysis. Tests have shown the sensor to be robust during long-term monitoring. When the sensor has been applied in unconfined aquifers, there has been virtually no observable difference in the responsiveness of the sensors. However, when the sensors are applied in reduced groundwater conditions, gradual fouling of the sensor surface has been seen to reduce the responsiveness of the sensor over time. Thus fouling can be an issue when applying the sensor in reduced conditions. The chloride sensors have shown to be very effective at measuring changes in chloride concentration in groundwater over short time spans. Therefore, the sensors would be particularly useful in monitoring changes in the saltwater - freshwater interface and seawater intrusion, as well as in groundwater tracer tests. In addition, the sensors could be easily applied in monitoring spills from waste disposal sites or well sites conducting hydraulic fracturing, where chloride would be one of the potential leachates to groundwater.

Thorn, P.; Mortensen, J.

2012-12-01

418

Choline chloride-thiourea, a deep eutectic solvent for the production of chitin nanofibers.  

PubMed

Deep eutectic solvents (DESs) consisting of the mixtures of choline halide (chloride/bromide)-urea and choline chloride-thiourea were used as solvents to prepare ?-chitin nanofibers (CNFs). CNFs of diameter 20-30 nm could be obtained using the DESs comprising of the mixture of choline chloride and thiourea (CCT 1:2); however, NFs could not be obtained using the DESs having urea (CCU 1:2) as hydrogen bond donor. The physicochemical properties of thus obtained NFs were compared with those obtained using a couple of imidazolium based ionic liquids namely, 1-butyl-3-methylimidazolium hydrogen sulphate [(Bmim)HSO4] and 1-methylimidazolium hydrogen sulphate [(Hmim)HSO4] as well as choline based bio-ILs namely, choline hydrogen sulphate [(Chol)HSO4] and choline acrylate. The CNFs obtained using the DES as a solvent were used to prepare calcium alginate bio-nanocomposite gel beads having enhanced elasticity in comparison to Ca-alginate beads. The bio-nanocomposite gel beads thus obtained were used to study slow release of 5-fluorouracil, an anticancer drug. PMID:24528755

Mukesh, Chandrakant; Mondal, Dibyendu; Sharma, Mukesh; Prasad, Kamalesh

2014-03-15

419

Occlusion and ion exchange in the molten (lithium chloride+potassium chloride+alkaline-earth chloride) salt+zeolite 4A system with alkaline-earth chlorides of calcium and strontium and in the molten (lithium chloride+potassium chloride+actinide chloride) salt+zeolite 4A system with the actinide chloride of uranium  

Microsoft Academic Search

The interaction between molten salts of the type LiCl-KCl-MeCl\\u000a n\\u000a (Me=Ca, Sr, U; \\u000a $$x_{MeCl_n } $$\\u000a = to 0.45; and x\\u000a KCl\\/x\\u000a LiCl=0.69) and zeolite 4A have been studied at 823 K. The main interactions between these salts and zeolite are molten salt occlusion\\u000a to form salt-loaded zeolite and ion exchange between the molten salt and salt-loaded zeolite. An irreversible

Dusan Lexa

2003-01-01

420

Discovery of the Calcium Isotopes  

E-print Network

Twenty four calcium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

J. L. Gross; M. Thoennessen

2010-04-28

421

Children's Bone Health and Calcium  

MedlinePLUS

... Research Information Clinical Trials Resources and Publications Children's Bone Health and Calcium: Condition Information Skip sharing on ... media links Share this: Page Content What is bone health and how do you build strong bones? ...

422

The structural consequences of calcium crystal deposition.  

PubMed

Calcium pyrophosphate dihydrate and basic calcium phosphate (BCP) crystals are the most common calcium-containing crystals associated with rheumatic disease. Clinical manifestations of calcium crystal deposition include acute or chronic inflammatory and degenerative arthritides and certain forms of periarthritis. The intra-articular presence of BCP crystals correlates with the degree of radiographic degeneration. Calcium crystal deposition contributes directly to joint degeneration. Vascular calcification is caused by the deposition of calcium hydroxyapatite crystals in the arterial intima. These deposits may contribute to local inflammation and promote further calcification, thus aggravating the atherosclerotic process. Calcium crystal deposition results in substantial structural consequence in humans. PMID:24703349

Durcan, Laura; Bolster, Ferdia; Kavanagh, Eoin C; McCarthy, Geraldine M

2014-05-01

423

Calcium dynamics in vascular smooth muscle  

PubMed Central

Smooth muscle cells are ultimately responsible for determining vascular luminal diameter and blood flow. Dynamic changes in intracellular calcium are a critical mechanism regulating vascular smooth muscle contractility. Processes influencing intracellular calcium are therefore important regulators of vascular function with physiological and pathophysiological consequences. In this review we discuss the major dynamic calcium signals identified and characterized in vascular smooth muscle cells. These signals vary with respect to their mechanisms of generation, temporal properties, and spatial distributions. The calcium signals discussed include calcium waves, junctional calcium transients, calcium sparks, calcium puffs, and L-type calcium channel sparklets. For each calcium signal we address underlying mechanisms, general properties, physiological importance, and regulation. PMID:23384444

Amberg, Gregory C.; Navedo, Manuel F.

2013-01-01

424

Calcium, vitamin D and cancer.  

PubMed

A low vitamin D status and inadequate calcium intake are important risk factors for various types of cancer. Ecological studies using solar UV-B exposure as an index of vitamin D3 photoproduction in the skin found a highly significant inverse association between UV-B and mortality in fifteen types of cancer. Of these, colon, rectal, breast, gastric, endometrial, renal and ovarian cancer exhibit a significant inverse relationship between incidence and oral intake of calcium. In addition, lung and endometrial cancer as well as multiple myeloma are considered calcium and vitamin D sensitive. Studies on tissue-specific expression of the CYP27B1-encoded 25-hdroxyvitamin D-1alpha-hydroxylase and of the extracellular calcium-sensing receptor (CaR) have led to an understanding how locally produced 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and extracellular Ca2+ act jointly as key regulators of cellular proliferation, differentiation and function. Thus, impairment of antimitogenic, proapoptotic and prodifferentiating signaling from the 1,25(OH)2D3-activated vitamin D receptor (VDR) and from the CaR in vitamin D and calcium insufficiency has been implicated in the pathogenesis of the aforementioned types of cancer. 1,25(OH)2D3 and calcium interact in modulating cell growth in different ways: (i) Signaling pathways from the VDR and the CaR converge on the same downstream elements, e.g. of the canonical Wnt pathway; (ii) high extracellular calcium modulates extrarenal vitamin D metabolism in favor of higher local steady-state concentrations of 1,25(OH)2D3; (iii) 1,25(OH)2D3 may up-regulate expression of the CaR and thus augment CaR-mediated antiproliferative responses to high extracellular Ca2+. This can explain why combined supplementation is required for optimal chemoprevention of cancer by calcium and vitamin D. PMID:19667166

Peterlik, Meinrad; Grant, William B; Cross, Heide S

2009-09-01

425

Medical therapy, calcium oxalate urolithiasis  

NASA Technical Reports Server (NTRS)

The development of diagnostic protocols that identify specific risk factors for calcium oxalate nephrolithiasis has led to the formulation of directed medical regimens that are aimed at correcting the underlying metabolic disturbances. Initiation of these treatment programs has reduced markedly the rate of stone formation in the majority of patients who form stones. This article discusses the rationale that underlies the choice of medical therapy for the various pathophysiologic causes of calcium oxalate nephrolithiasis and the appropriate use of available medications.

Ruml, L. A.; Pearle, M. S.; Pak, C. Y.

1997-01-01

426

CASE REPORT Calcium Oxalate Precipitates  

E-print Network

We report a case of calcium oxalate deposition in a renomedullary interstitial cell tumor (RICT) in a patient dying of full-blown AIDS. The precipitates showed birefringence using a partially polaris ed light and were stained black in Yasue’s silver nit rate-rubeanic acid method. The combination of calcium oxalosis and RICT has not been reported before and might possibly be due to systemic biochemical alterations of the glycosaminoglycans as a result of profound metabolic disturbances in AIDS

Irene Pecorella; Sebastian B Lucas; Antonio Ciardi; Lorenzo Memeo; Robert F Miller

427

Calcium Intake and Body Weight  

Microsoft Academic Search

ABSTRACT Five clinical studies of calcium intake, designed with a primary skeletal end point, were reevaluated to explore associations be- tween calcium intake and body weight. All subjects were women, clustered in three main age groups: 3rd, 5th, and 8th decades. Total sample,size was,780. Four of the studies,were,observational;,two were cross-sectional, in which body mass index was regressed against entry level

K. Michael Davies; Robert P. Heaney; Robert R. Recker; Joan M. Lappe; M. Janet Barger-lux; Karen Rafferty; Sharilyn Hinders

2000-01-01

428

Bioactivity in silica/poly(?-glutamic acid) sol-gel hybrids through calcium chelation.  

PubMed

Bioactive glasses and inorganic/organic hybrids have great potential as biomedical implant materials. Sol-gel hybrids with interpenetrating networks of silica and biodegradable polymers can combine the bioactive properties of a glass with the toughness of a polymer. However, traditional calcium sources such as calcium nitrate and calcium chloride are unsuitable for hybrids. In this study calcium was incorporated by chelation to the polymer component. The calcium salt form of poly(?-glutamic acid) (?CaPGA) was synthesized for use as both a calcium source and as the biodegradable toughening component of the hybrids. Hybrids of 40wt.% ?CaPGA were successfully formed and had fine scale integration of Ca and Si ions, according to secondary ion mass spectrometry imaging, indicating a homogeneous distribution of organic and inorganic components. (29)Si magic angle spinning nuclear magnetic resonance data demonstrated that the network connectivity was unaltered with changing polymer molecular weight, as there was no perturbation to the overall Si speciation and silica network formation. Upon immersion in simulated body fluid a hydroxycarbonate apatite surface layer formed on the hybrids within 1week. The polymer molecular weight (Mw 30-120kDa) affected the mechanical properties of the resulting hybrids, but all hybrids had large strains to failure, >26%, and compressive strengths, in excess of 300MPa. The large strain to failure values showed that ?CaPGA hybrids exhibited non-brittle behaviour whilst also incorporating calcium. Thus calcium incorporation by chelation to the polymer component is justified as a novel approach in hybrids for biomedical materials. PMID:23632373

Valliant, Esther M; Romer, Frederik; Wang, Daming; McPhail, David S; Smith, Mark E; Hanna, John V; Jones, Julian R

2013-08-01

429

IP3 Receptor-Operated Calcium Entry  

NSDL National Science Digital Library

This Perspective by Mikoshiba and Hattori is the third in a series on cellular calcium release mechanisms. The authors describe the regulated release of calcium from intracellular stores by the inositol 1,4,5 trisphosphate receptor (IP3R) and the relationship of this release mechanism to calcium influx from the extracellular milieu through store-operated calcium channels. They discuss a model proposing that intracellular and plasma membrane calcium channels are functionally and physically coupled.

Katsuhiko Mikoshiba (Japan;University of Tokyo and the Laboratory for Developmental Neurobiology REV); Mitsuharu Hattori (Japan;University of Tokyo and the Laboratory for Developmental Neurobiology REV)

2000-09-26

430

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.  

Code of Federal Regulations, 2011 CFR

...prepared from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with acrylonitrile, methyl...units derived from vinyldene chloride. (c) Optional adjuvant...desired properties may include sodium...

2011-04-01

431

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.  

Code of Federal Regulations, 2011 CFR

...units derived from vinylidene chloride. The finished coating produced from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with methyl methacrylate...desired properties may include sodium...

2011-04-01

432

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.  

Code of Federal Regulations, 2013 CFR

...prepared from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with acrylonitrile, methyl...units derived from vinyldene chloride. (c) Optional adjuvant...desired properties may include sodium...

2013-04-01

433

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.  

...prepared from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with acrylonitrile, methyl...units derived from vinyldene chloride. (c) Optional adjuvant...desired properties may include sodium...

2014-04-01

434

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.  

Code of Federal Regulations, 2010 CFR

...prepared from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with acrylonitrile, methyl...units derived from vinyldene chloride. (c) Optional adjuvant...desired properties may include sodium...

2010-04-01

435

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.  

Code of Federal Regulations, 2012 CFR

...units derived from vinylidene chloride. The finished coating produced from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with methyl methacrylate...desired properties may include sodium...

2012-04-01

436

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.  

Code of Federal Regulations, 2010 CFR

...units derived from vinylidene chloride. The finished coating produced from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with methyl methacrylate...desired properties may include sodium...

2010-04-01

437

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.  

Code of Federal Regulations, 2013 CFR

...units derived from vinylidene chloride. The finished coating produced from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with methyl methacrylate...desired properties may include sodium...

2013-04-01

438

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.  

...units derived from vinylidene chloride. The finished coating produced from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with methyl methacrylate...desired properties may include sodium...

2014-04-01

439

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.  

Code of Federal Regulations, 2012 CFR

...prepared from vinylidene chloride copolymers produced by copolymerizing vinylidene chloride with acrylonitrile, methyl...units derived from vinyldene chloride. (c) Optional adjuvant...desired properties may include sodium...

2012-04-01

440

40 CFR 415.10 - Applicability; description of the aluminum chloride production subcategory.  

Code of Federal Regulations, 2012 CFR

... Applicability; description of the aluminum chloride production subcategory. 415...MANUFACTURING POINT SOURCE CATEGORY Aluminum Chloride Production Subcategory § 415.10 Applicability; description of the aluminum chloride production...

2012-07-01

441

Management of life-threatening calcium channel blocker overdose with continuous veno-venous hemodiafiltration with charcoal hemoperfusion.  

PubMed

Cases of calcium channel blocker overdose reported from India are few, and although rare, they are associated with high mortality. Management includes fluids, vasopressors, calcium gluconate or chloride, glucagon infusion, and hyperinsulinemia-euglycemia therapy along with some rescue therapies tried in anecdotal reports. We report here a case of life-threatening overdose of amlodipine with shock, refractory to conventional therapies. Salvage therapy with continuous veno-venous hemodiafiltration using charcoal hemoperfusion with prior infusion of intravenous lipid emulsion resulted in a successful outcome. PMID:24987241

Garg, Suneel K; Goyal, Pankaj K; Kumar, Rahul; Juneja, Deven; Bhasin, Alka; Singh, Omender

2014-06-01

442

Management of life-threatening calcium channel blocker overdose with continuous veno-venous hemodiafiltration with charcoal hemoperfusion  

PubMed Central

Cases of calcium channel blocker overdose reported from India are few, and although rare, they are associated with high mortality. Management includes fluids, vasopressors, calcium gluconate or chloride, glucagon infusion, and hyperinsulinemia-euglycemia therapy along with some rescue therapies tried in anecdotal reports. We report here a case of life-threatening overdose of amlodipine with shock, refractory to conventional therapies. Salvage therapy with continuous veno-venous hemodiafiltration using charcoal hemoperfusion with prior infusion of intravenous lipid emulsion resulted in a successful outcome. PMID:24987241

Garg, Suneel K.; Goyal, Pankaj K.; Kumar, Rahul; Juneja, Deven; Bhasin, Alka; Singh, Omender

2014-01-01

443

Clogging and Cementation Caused by Calcium or Iron Biogrouts  

NASA Astrophysics Data System (ADS)

Chemical grouts are often used to reduce the hydraulic conductivity of soil for seepage control purposes. However, chemical grouts can be expensive and environmentally unfriendly. Therefore, two new biogrouts were tested for their bioclogging and biocementation properties. The first was calcium-based biogrout, which contained urease-producing bacteria, calcium chloride and urea for the crystallization of calcite due to enzymatic hydrolysis of urea. The second was iron-based biogrout, which consisted of urease-producing bacteria, ferric chelate, and urea for the precipitation of ferric hydroxide and carbonate due to enzymatic hydrolysis of urea. The permeability of sand (P, 10^-5 m/s), treated with calcium-based biogrout, linearly decreased as a function of the content of precipitated calcium (C, % w/w) according to the following equation: P = 5.1 - 4.0 C. Meanwhile, the permeability of sand treated with iron-based biogrout dropped to 2.7x10^-6 m/s at content of precipitated iron (F, % w/w) about 0.35 % w/w , by the equation: P = 5.1 - 14.6 F , and then slowly decreased to 1.4x10^-7 m/s at content of precipitated iron 1.8% w/w by the following equation: P = 0.36 - 0.23F. Both biogrouts have approximately same efficiency in the reduction of permeability of sand to low values. However, the mechanisms of bioclogging are probably different because the reduction of permeability by calcium-based biogrout was described by linear function of precipitated calcium but the reduction of permeability by iron-based biogrout showed two steps of the clogging. Different functions and mechanisms were related probably to the different type of precipitates. The images of biogrouted sand samples show that calcium-based biogrout produced white amorphous or crystallised calcium carbonate, while iron-based biogrout produced gel-like brown precipitate without visible crystals. The unconfined compressive strengths of the sand treated with different biogrouts (Y, kPa) increased by power function of the precipitated metal content (X, % ww-1) according to the following equations: Y = 14.7X^2 -0.72 X for calcium-based biogrout, and Y = 13.6X^2 + 37.0 X for iron-based biogrout. The strength of wet biocemented sand at the content of precipitated metals below 1.5 % w/w was very low and only at the content of precipitated metal above 3% w/w it was increased to 230 - 240 kPa. Therefore, major geotechnical applications of calcium-based and iron-based biogrouts at the contents of the precipitated metal below 1.5% could be bioclogging of the porous soil rather than its strengthening. This bioclogging could be applicable to the sealing the aquaculture or wastewater treatment ponds, construction of the algal biofuel production ponds, landfill sites, as well as for the plugging of the piping in dams, retaining walls, channels or reservoirs in sandy soil.

Ivanov, V.; Chu, J.; Naeimi, M.

2012-12-01

444

Methyl chloride via oxyhydrochlorination of methane  

SciTech Connect

Work to develop a highly selective methyl chloride synthesis catalyst continued, but no stable catalyst with >80% selectivity at 20% methane exists yet. Effort was made on finalizing the pre- engineering scope definition of the Process Demonstration Unit. Natural gas purification, reactor, reactor effluent and MeCl purification, and anhydrous HCl recovery are discussed.

Naasz, B.

1993-03-04

445

HEALTH ASSESSMENT DOCUMENT FOR DICHLOROMETHANE (METHYLENE CHLORIDE)  

EPA Science Inventory

Dichloromethane (methylene chloride) is known to be metabolized to carbon monoxide in man and animals, primarily by the liver. Because the oxygen content of blood is decreased, depriving the brain and heart of the oxygen they require, serious permanent damage may result. Carboxyh...