WorldWideScience
1

Advancing Age Alters the Contribution of Calcium Release From Smooth Endoplasmic Reticulum Stores in Superior Cervical Ganglion Cells  

UK PubMed Central (United Kingdom)

In superior cervical ganglion (SCG) neurons calcium-induced calcium release (CICR), mediated by ryanodine receptors (RyRs), contributes to stimulation-evoked intracellular calcium ([Ca2+]i)...Full Text Available

2009-01-01

2

Health-hazard evaluation report HETA 85-354-1872, Asarco, Denver, Colorado  

Science.gov (United States)

An evaluation was made of possible hazardous working conditions at the ASARCO Globe facility, Denver, Colorado. The facility was involved in the recovery of cadmium from baghouse dust, a waste byproduct of nonferrous smelters. A medical study of kidney function was conducted in 45 current or former cadmium production workers; results were compared to those for 35 hospital workers. Kidney abnormalities were more common and more severe in the cadmium workers than in the hospital workers. Abnormalities of proximal tubular function included reduced reabsorption of beta-2-microglobulin, retinol binding protein, calcium and phosphate. Glomerular dysfunction was evidenced as elevated serum creatinine. As length of exposure to cadmium increased, changes became more apparent in workers. No reversal of the conditions was noted in workers who had ceased to be exposed to ...

1988-02-01

3

Determination of some minor and trace elements in iron ores by ion exchange chromatography, spectrophotometry and atomic absorption spectrometry  

International Nuclear Information System (INIS)

A method is described for determination of aluminium, cadmium, cobalt, chromium, copper, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, zinc, titanium and vanadium in iron ore. After dissolution, a 1 gram sample of iron ore is applied to a column of AGI-X8 anion exchange resin (chloride form), in 100 ml of 7M HCl. Aluminium, chromium, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, titanium and vanadium are eluted with 7M HCl; iron, copper and cobalt are eluted with 0.5M HCl; cadmium and zinc are eluted with 2M HNO_3. Iron is subsequently removed from copper and cobalt by a solvent extraction with methyl isobutyl ketone. The elements are determined in the eluates by atomic absorption spectrometry, except for titanium and vanadium, which are determined spectrophotometrically.

4

The role of metallothionein IIa in defending lens epithelial cells against cadmium and TBHP induced oxidative stress  

UK PubMed Central (United Kingdom)

PurposeHeavy metals and other forms of oxidative stress have been implicated as key factors in the formation of age-related cataract in humans. Metallothioneins are...Full Text Available

5

The separation and determination of trace elements in iron ore  

International Nuclear Information System (INIS)

The separation, concentration, and determination of trace elements in iron ores are described. After the sample has been dissolved, the iron is separated by liquid-liquid extraction with a liquid cation-exchanger, di-(2-ethylhexyl) phosphoric acid. The trace elements aluminium, cadmium, calcium, chromium, cobalt, copper, lead, magnesium, manganese, mercury, potassium, sodium, vanadium, and zinc are determined in the aqueous phase by atomic-absorption spectrophotometry.

2008-05-01

6

Age-dependent changes in Ca2+ homeostasis in peripheral neurones: implications for changes in function  

UK PubMed Central (United Kingdom)

Calcium ions represent universal second messengers within neuronal cells integrating multiple cellular functions, such as release of neurotransmitters, gene expression, proliferation, excitability,...Full Text Available

2007-06-01

7

Phase diagrams  

International Nuclear Information System (INIS)

The description is presented of binary phase diagrams of titanium alloyed with the following elements: silver, aluminium, arsenic, gold, boron, barium, beryllium, bismuth, carbon, calcium, cadmium, cobalt, chromium, copper, iron, gallium, germanium, hydrogen, hafnium, indium, iridium, potassium, lithium, magnesium, manganese, molybdenum, nitrogen, sodium, niobium, nickel, oxygen, osmium, phosphorus, lead, palladium, platinum, plutonium, rhenium, lanthanium, cerium, preseodymium, neodymium, gadolinium, erbium, terbium, thulium, lutetium, rhodium, ruthenium, scandium, silicon, tin, strontium, tantalum, technetium, thorium, uranium, vanadium, tungsten, yttrium, ytterbium, zinc and zirconium.

8

Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Progress report, January 1, 1979-December 31, 1979  

International Nuclear Information System (INIS)

The mechanism of lead transport is presented, and especially the particular similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined cockerels, raised on a commercial diet or on a specified diet, using in vivo ligated loop procedure. The dose administered into the loop contained 0.5 #mu#Ci "2"0"3Pb (and/or 0.1 #mu#Ci "4"7Ca), and 0.01 mM lead acetate (and/or mM CaCl_2) in 0.5 ml 0.15 M NaCl,pH 6.5. It was shown that lead is rapidly taken up by the mucosal tissue, and slowly transferred into the body, whereas less calcium is retained by the tissue and the transfer of calcium is many times as effective as that for lead. They appear to respond in a similar manner to a low calcium intake and vitamin D treatment. Increasing luminal stable lead concentration significantly reduced the percentage of radiolead significantly reduced the percentage of ...

9

Distribution of blood lead, blood cadmium, urinary cadmium, and urinary arsenic levels in employees of a copper smelter  

Energy Technology Data Exchange (ETDEWEB)

A cross-sectional medical examination of a copper smelter work force included determination of blood lead (Pb-B), zinc protoporphyrin (ZPP), blood cadmium (Cd-B), urinary cadmium (Cd-U), and urinary arsenic (As-U), since it was known that such metal impurities were present in the copper concentrate. A total of 776 copper smelter employees (680 active and 96 retirees and ex-employees) were examined. Another 144 men, never employed in the smelter, but who had worked in copper mines (and sometimes in gold mines) were also examined. Mean Pb-B, ZPP, Cd-B, and As-U were significantly higher in active copper smelter employees than in retirees or miners, indicating exposure and absorption in the copper smelter. Significant correlations between Pb-B and Cd-B, and Cd-U and As-U were present, confirming the common source of absorption. Although there was evidence for an increased lead absorption, this was very moderate, with practically no Pb-B levels in ...

1984-02-01

10

Catalytic desulfurization of organic sulfur compounds over zeolite catalysts  

Energy Technology Data Exchange (ETDEWEB)

In the dehydrodesulfurization of ethanethiol at 400/sup 0/C, the activities of sodium X, Y, and A zeolites decreased in the order given as did the activities of nickel, cobalt, zinc, cadmium, copper, silver, lead, manganese, barium, calcium, sodium, and iron Y zeolite catalysts. A volcano-shape order was observed between the catalytic activity and the electronegativity of the metal ions. The changes in the activity of hydrogen Y zeolite catalyst in ethanethiol dehydrodesulfurization and cumene dealkylation by calcination agreed with the decrease in the Broensted acidity but were independent of Lewis acidity. For hydrodesulfurization of thiophene, the activities of nickel, cobalt, copper, and silver Y zeolite catalysts decreased in the order given and were greater than for a commercial hydrodesulfurization catalyst; reduced and presulfided catalysts showed selective hydrodesulfurization activity. Addition of 5% of nickel or molybdenum oxides to ...

1980-01-01

12

Gastrointestinal absorption of lead (/sup 203/Pb) in chicks: influence of lead, calcium, and age  

Energy Technology Data Exchange (ETDEWEB)

The present study was designed to investigate, in more detail, the mechanism of lead transport by the gastrointestinal tract and particularly the similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined in 3-week-old white Leghorn cockerels, raised on a commercial diet or special diets, using an in vivo ligated loop procedure. The dose administered into the loop usually contained 0.5 ..mu..Ci /sup 203/Pb (and/or 0.1 ..mu..Ci /sup 47/Ca), 0.01 mM lead acetate (and/or 1 mM CaCl/sub 2/) in 0.5 ml of 0.15 M NaCl, pH 6.5. It was shown that lead is rapidly taken up by the intestinal tissue, and only slowly transferred into the circulation whereas calcium, also accumulated rapidly by the tissue, is rapidly released from the tissue in the serosal direction. The absorption processes of these cations show similar responses to various experimental conditions (low calcium ...

1981-10-01

13

Difference in the effects produced by non-radioactive and radioactive calcium  

International Nuclear Information System (INIS)

... aluminum calcium calcium 45 cations citric acid corrosion inhibition radiation

16

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering  

Energy Technology Data Exchange (ETDEWEB)

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or ...

1994-01-01

17

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering  

Energy Technology Data Exchange (ETDEWEB)

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or ...

1994-11-22

18

Trace metal characterization of the U-Al matrix by atomic spectroscopy  

International Nuclear Information System (INIS)

Uranium-aluminum alloys with a significant enrichment of uranium with "2"3"3U or "2"3"5U serve as nuclear fuels in research reactors. The quality assurance of this fuel requires, among other things, precise knowledge that all trace metal constituents that affect neutron economy, fuel integrity, and fuel fabrication process parameters are well within the specification limits. Trace metal characterization of "2"3"5U-Al alloy has been carried out by atomic spectrometry. The trace metal constituents of interest are grouped into common metals (silver, boron, calcium, cadmium, cobalt, chromium, copper, iron, magnesium, manganese, molybdenum, sodium, nickel, lead, silicon, tin, titanium, vanadium, tungsten, and zinc) and lanthanides (cerium, dysprosium, europium, gadolinium, holminium, lutetium, samarium, and terbium). The elements yttrium and zirconium are grouped with the latter in view of the chemical separation procedure used. The alloy samples ...

20

Reduction of cadmium toxicity to green microalga Stichococcus bacillaris by manganese  

Energy Technology Data Exchange (ETDEWEB)

Investigations of cadmium toxicity to microorganisms are now more concerned with the interactions of cadmium with different environmental factors and other metals. The interactions are complex and have not been thoroughly studied yet. Metal interactions may assume the form of synergism characterized by increase in toxicity, but also of antagonism in which one metal reduces the toxicity of another. Apart from cadmium interactions with such toxic metals as mercury and lead, interactions of cadmium with the essential trace elements seem to be very interesting because it has been assumed that algal cells take up cadmium by the system transporting these elements. A previous study showed that cadmium transport into Stichococcus bacillaris cells was inhibited by Mn/sup 2 +/ ions. Thus, it can be supported that there exist some possibilities of using those ions ...

1988-12-01

21

Blood cadmium concentrations in the general population of Umbria, Central Italy  

Energy Technology Data Exchange (ETDEWEB)

The aims of this study were (a) to assess blood cadmium (B-Cd) concentrations and to establish a tentative reference interval; (b) to identify significant determinants of B-Cd, in a population from Umbria, Central Italy, which was not occupationally exposed to cadmium (Cd). Four hundred and thirty-four healthy blood-donors volunteered to answer a questionnaire and provide a blood sample for B-Cd analysis, which was performed by graphite furnace atomic absorption spectrophotometry. Blood Cd concentrations ranged from non-detectable values, i.e. below 0.1 {mu}g/l up to 3.4 {mu}g/l and were not normally distributed. The median values and the 95th percentiles were 0.7 and 2.0 {mu}g/l, respectively. Concentrations of B-Cd were more than double in smokers than in non-smokers, median values being 1.1 {mu}g/l and 0.5 {mu}g/l, respectively. In current smokers, B-Cd values correlated with the number of cigarettes smoked daily (r{sub s}=0.40, P=0.0001) ...

1999-02-02

22

Age sensitivity of juvenile mussels (Utterbackia imbeciles Say) to copper and cadmium exposure  

Energy Technology Data Exchange (ETDEWEB)

In recent years, there has been increased interest in using early life stages of freshwater bivalves to test the toxicity of dissolved constituents in water. The authors have developed laboratory and in situ assays with artificially cultured Utterbackia imbecillis to examine effects of contaminants and existing conditions in embayments and rivers on mortality and reproductive success of unionid mussels. Age sensitivity of U. imbecillis to Cd and Cu was examined using both static acute and 8-day static renewal bioassays. Both aqueous and sediment exposures demonstrated greater sensitivity to Cd than Cu. LC{sub 50}`s for two-day old (2d) and 9d mussels were approximately half the LC{sub 50} calculated for 16d mussels in 48-hr bioassays with Cd. Additionally, acute assays were repeated twice to examine variability in response between different mussel cultures to the two metals. The results of this work reinforce the potential of juvenile U. imbecillis as a standard ...

1994-12-31

23

The quest to beat aging  

CERN Document Server

The quest to beat aging

2000-01-01

25

Augmented behavioral response and enhanced synaptosomal calcium transport induced by repeated cocaine administration are decreased by calcium channel blockers  

UK PubMed Central (United Kingdom)

Recent studies suggest that calcium influx via L-type calcium channels is necessary for psychostimulant-induced behavioral sensitization. In addition, chronic amphetamine upregulates subtype...Full Text Available

2007-07-26

26

The method for iron removal from cadmium in the course of refining process; Sposob usuwania zelaza z kadmu w procesie jego rafinacji  

Energy Technology Data Exchange (ETDEWEB)

The pyrometallurgic method consisting in introduction of refining agent into the liquid cadmium has been presented. The refining agent consisting of silicon nitride, carbon dust and sodium hydroxide has been added in several portion into the liquid cadmium. Iron has been removed from the cadmium surface in the form of floating slag.

1992-10-30

27

Testing of solar cells for communication satellites  

International Nuclear Information System (INIS)

... cadmium sulfides communications electrons performance testing physical

28

Pyrolysis of dichlorodithiourea cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

By means of infrared spectroscopy, x-ray diffraction, and differential thermal analysis, the authors investigate the pyrolysis of dichlorodithiourea cadmium, the vapor phase epitaxy of the cadmium sulfide film, and the composition of the solid and gaseous pyrolysis products. Those products are found to include the thiocyanates of guanidine, ammonium, and hydrogen along with cadmium oxides and sulfates and hydrochloric acid.

1987-02-20

29

Electrochemical Solar Energy Converter  

International Science & Technology Center (ISTC)

Elaboration of Electrochemical Solar Energy Converter Incorporating Cadmium Selenide Semiconductor Developed Electrochemically

31

Carbon tetrachloride-induced release of calcium from isolated hepatocytes  

International Nuclear Information System (INIS)

Studies have shown that CCl_4 administration to rats inhibits endoplasmic reticulum calcium pump activity and reduces the amount of calcium associated with subsequently isolated microsomal subcellular fractions. This report confirms that exposure of isolated hepatocytes to CCl_4 rapidly produces these effects in isolated parenchymal cells and demonstrates that when isolated hepacytes are exposed to CCl_4 calcium is rapidly released from cells. This release can be detected with a calcium ion-selective electrode when cells are incubated in a medium with low extracellular calcium. Calcium released from an intracellular pool(s) may initiate hepatotoxic changes in liver. (author).

32

Isotope fractionations and radiocarbon ages of beach rock samples collected from the Nansei Islands, southwest of Japan  

International Nuclear Information System (INIS)

Beach rocks are observed frequently on the tropical and subtropical sandy beaches where they express thin beds dipping seaward at less than 15 degrees. They consist of beach sediments including fossil shells, fragments of corals, diatoms and other biocarbonates, and are well cemented within the inter-tidal zone with calcium carbonate originated in sea water. Therefore, they are not only good indicators which show the past sea level, but also provide good sample material for radiocarbon dating. The locations of beach rocks give us an optimum condition studying a carbon cycle between land and marine environment by analyzing their isotope fractionations. In order to estimate the origin of calcium carbonate which worked as an adhesive when beach rocks were formed and to estimate the formative ages of beach rocks, a total of 330 fossil corals, fossil shells and calcarenite or calcirdite samples were collected from 128 sites of ...

2004-10-25

33

Crystal Structure of Human Senescence Marker Protein 30: Insights Linking Structural, Enzymatic, and Physiological Functions  

Energy Technology Data Exchange (ETDEWEB)

Human senescence marker protein 30 (SMP30), which functions enzymatically as a lactonase, hydrolyzes various carbohydrate lactones. The penultimate step in vitamin-C biosynthesis is catalyzed by this enzyme in nonprimate mammals. It has also been implicated as an organophosphate hydrolase, with the ability to hydrolyze diisopropyl phosphofluoridate and other nerve agents. SMP30 was originally identified as an aging marker protein, whose expression decreased androgen independently in aging cells. SMP30 is also referred to as regucalcin and has been suggested to have functions in calcium homeostasis. The crystal structure of the human enzyme has been solved from X-ray diffraction data collected to a resolution of 1.4 {angstrom}. The protein has a 6-bladed {beta}-propeller fold, and it contains a single metal ion. Crystal structures have been solved with the metal site bound with either a Ca{sup 2+} or a Zn{sup 2+} atom. The ...

2010-05-25

34

Photocatalytic hydrogen production from solutions of sulfite using platinized cadmium sulfide powder  

Energy Technology Data Exchange (ETDEWEB)

Platinized cadmium sulfide powder suspended in a solution of sodium sulfite produces hydrogen efficiently by visible light. Sulfite ions are oxidized to sulfate and dithionate ions. 4 figures.

1983-09-29

35

Nitrogen nutrient status induces sexual differences in responses to cadmium in Populus yunnanensis  

UK PubMed Central (United Kingdom)

Populus yunnanensis was employed as a model species to detect sexual differences in growth, physiological, biochemical, and ultrastructural responses to cadmium (Cd) stress, nitrogen...Full Text Available

2011-10-01

36

Localization and Toxic Effects of Cadmium, Copper, and Uranium in Azolla1  

UK PubMed Central (United Kingdom)

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis....Full Text Available

1988-09-01

37

Cadmium, Lead, and Other Metals in Relation to Semen Quality: Human Evidence for Molybdenum as a Male Reproductive Toxicant  

UK PubMed Central (United Kingdom)

BackgroundEvidence on human semen quality as it relates to exposure to various metals, both essential (e.g., zinc, copper) and nonessential (e.g., cadmium, lead), is inconsistent....Full Text Available

2008-11-01

38

Analysis of control methods: mercury and cadmium pollution.  

UK PubMed Central (United Kingdom)

Physical system conceptual models are developed to illustrate the various interconnecting pathways of metal flow. Economic use of mercury and cadmium, as representative toxic heavy metals, is inventoried,...Full Text Available

1975-12-01

39

Method of forming solar cells by grid contact isolation  

Energy Technology Data Exchange (ETDEWEB)

A solar cell structure is produced by a method comprising baking the solar cell, containing a gridded top layer of cuprous sulfide formed on a base of cadmium sulfide, for 20 minutes to 10 hours, to produce a copper doped cds electrically insulating region in the cadmium sulfide base near the interface of the cuprous sulfide and the cadmium sulfide; removing the cuprous sulfide, and the copper doped cds insulating region not covered by the grid, to provide a bare cadmium sulfide areas; and then forming a cuprous sulfide layer on the exposed areas not covered by the grid.

1982-03-16

40

Diffusion Zink Planting of Steels  

International Science & Technology Center (ISTC)

Research on Diffusion Zinc Cladding of Structural Steels, as Well as Their Mechanical and Corrosion Properties to Replace Their Cyanic Cadmium Plating

42

Spatiotemporal intracellular calcium dynamics during cardiac alternans  

UK PubMed Central (United Kingdom)

Cellular calcium transient alternans are beat-to-beat alternations in the peak cytosolic calcium concentration exhibited by cardiac cells during rapid electrical stimulation or under pathological conditions....Full Text Available

2009-09-01

43

Sodium/Calcium Exchangers Selectively Regulate Calcium Signaling in Mouse Taste Receptor Cells  

UK PubMed Central (United Kingdom)

Taste cells use multiple signaling mechanisms to generate appropriate cellular responses to discrete taste stimuli. Some taste stimuli activate G protein coupled receptors (GPCRs) that cause calcium...Full Text Available

2010-07-01

44

Role of plasma membrane calcium ATPase 2 in spinal cord pathology  

UK PubMed Central (United Kingdom)

A number of studies have indicated that plasma membrane calcium ATPases (PMCAs) are expressed in the brain and spinal cord and could play important roles not only in the maintenance of cellular calcium...Full Text Available

2010-05-26

45

Hypertrophy and Heart Failure in Mice Overexpressing the Cardiac Sodium-Calcium Exchanger  

UK PubMed Central (United Kingdom)

Background:The cardiac sodium–calcium exchanger (NCX1) is a key sarcolemmal protein for the maintenance of calcium homeostasis in the heart. Since heart failure...Full Text Available

2007-05-01

46

Demographic, Dietary, and Urinary Factors and 24-h Urinary Calcium Excretion  

UK PubMed Central (United Kingdom)

Background and objectives: Higher urinary calcium is a risk factor for nephrolithiasis. This study delineated associations between demographic, dietary, and urinary factors and 24-h urinary calcium.Design,...Full Text Available

2009-12-01

47

Calcium Requirements and Metabolism in Chinese-American Boys and Girls  

UK PubMed Central (United Kingdom)

Calcium requirements of North American adolescents were set at 1300 mg/day based on data from white girls. Calcium requirements for Asian-American adolescents have not been studied. Using metabolic...Full Text Available

2010-08-01

48

Tracing Cadmium from Culture to Spikelet: Noninvasive Imaging and Quantitative Characterization of Absorption, Transport, and Accumulation of Cadmium in an Intact Rice Plant1[W][OA]  

UK PubMed Central (United Kingdom)

We characterized the absorption and short-term translocation of cadmium (Cd) in rice (Oryza sativa ‘Nipponbare’) quantitatively using serial images observed with a positron-emitting...Full Text Available

2010-04-01

49

The recovery of zinc and cadmium following 6.1 MeV alpha particle irradiation at 4.2 K  

International Nuclear Information System (INIS)

The paper reports the recovery of zinc and cadmium following 6.1 MeV alpha particle irradiation at 4.2 K as studied by means of electrical reistivity measurements. Specimens of 10 #mu#m thick have been used in order to obtain a homogeneous defect distribution over the whole thickness of the specimen. The pre-irradiation resistivity ratios were 700 and 750 for cadmium and zinc, respectively. (Auth.).

50

Single-crystalline cadmium telluride anodic oxidation kinetics  

Science.gov (United States)

The authors have determined quantitative characteristics for oxide films forming on (111) surfaces of cadmium telluride single crystals on anodic oxidation in 0.1 M KOH: the constants in the Guenterschulze-Betz equation and the film growth constant, which is 2.4 nm/V, from which the activation energy for cadmium telluride electrooxidation has been calculated.

1988-10-10

51

Cadmium down-regulation of kidney Sp1 binding to mouse SGLT1 and SGLT2 gene promoters: Possible reaction of cadmium with the zinc finger domain of Sp1  

UK PubMed Central (United Kingdom)

Cadmium (Cd) exposure causes glucosuria (glucose in the urine). Previously, it was shown that Cd exposure of primary cultures of mouse kidney cells (PMKC) decreased mRNA levels of the glucose...Full Text Available

2010-05-01

52

Effect of calcium and phosphorus on the gastrointestinal absorption of /sup 203/Pb in man  

Energy Technology Data Exchange (ETDEWEB)

Calcium and phosphorus were mainly responsible for reducing the gastrointestinal absorption of lead in human subjects. The effect of calcium was greater than phosphorus, and their combined effect was more than additive. Increasing weights of calcium and phosphorus progressively reduced lead absorption. The relationship between absorption and increasing weights could be described by two negative exponentials. These effects could be explained if lead competed with calcium and phosphorus for common transport mechanisms in the gut. Milk was also found to reduce lead absorption. Adding milk to the diet of people with low dietary calcium intake could reduce the possibility of increased absorption of ingested lead.

1983-02-01

53

Refilling Intracellular Calcium Stores  

UK PubMed Central (United Kingdom)

Within the cardiac cell, the movements of calcium ions are tightly regulated by a number of regulatory proteins including pumps, and channels. The sarcoplasmic reticulum (SR) is in large part...Full Text Available

2010-01-01

54

Calcium-Actin Waves and Oscillations of Cellular Membranes  

UK PubMed Central (United Kingdom)

AbstractWe propose a mechanism for the formation of membrane oscillations and traveling waves, which arise due to the coupling between the actin cytoskeleton and the calcium flux through...Full Text Available

2009-09-16

56

Estimation of the age of the universe by the nucleochronology method  

Energy Technology Data Exchange (ETDEWEB)

Unconditional estimates are suggested for the age of radioactive nuclei and hence for the age of the Universe.

1983-10-01

57

In vivo effects of cadmium chloride on certain aspects of protein metabolism in tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Heavy metals discharged from industries are a major source of pollution which has become a threat to all forms of life. Among the various heavy metals, cadmium is known to be highly toxic even in low concentrations. The harmful effects of cadmium is attributed to its effects on sulfhydryl groups of enzymes, especially dehydrogenases. Various aspects of cadmium pollution on fishes have been extensively reviewed. A survey of the literature reveals that few attempts have been made to study the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, has received little attention. The present study reports the influence of cadmium on certain aspects of protein metabolism in the tissues of a freshwater field crab, Barytelphusa guerini, and important ...

1991-04-01

58

Assessment of cadmium in aquatic sediment using dialysis samplers with ion-exchange-resin collection  

Energy Technology Data Exchange (ETDEWEB)

Simultaneously extracted metals (SEM) and acid volatile sulfide (AVS) show the potential for toxicity on the basis of their ratio. Accordingly, the authors spiked cadmium in a range for which Cd/AVS ratios were from 0.2 to 10 in the sediment with its weight about 8 kg in each batch. Dialysis samplers with a cation ion-exchange resin (Dowex 50W-X4) collection were used in a laboratory for the determination of free cadmium concentrations in pore water of the collected sediment. When equilibrium was reached among cadmium in pore water, sediment, and ion-exchange resin, cadmium exchanged onto resin phase was regenerated with 1 N hydrochloric acid (OPTIMA grade) and determined using an atomic absorption spectrophotometer (Zeeman 5000) with a graphite furnace accessory. Cadmium determined using the dialysis sampler is considered as free cadmium which is related to the ...

1998-05-01

59

Comparison of growth-induced resorption and denervation-induced resorption on the release of (/sup 3/H)tetracycline, /sup 45/calcium, and (/sup 3/H)collagen from whole bones of growing rats  

Energy Technology Data Exchange (ETDEWEB)

The major effect of immobilization during growth is a smaller bone mass induced by either an increased bone resorption or a decreased bone formation. Using a method of analyzing radioisotopic loss of (/sup 3/H)tetracycline and (/sup 3/H)collagen from bone prelabeled in vivo, we compared the amount of bone resorption due to immobilization with bone resorption induced by growth. One hind limb was denervated in growing male rats, 6 weeks of age, that had been chronically prelabeled with (/sup 3/H)tetracycline, /sup 45/calcium, and (/sup 3/H)proline. The total radioactivity of the whole femur and tibia/fibula from the denervated limb was compared with that from bones of the control limb at 0, 1, 2, 4, and 8 weeks after denervation. The effect of growth on bone formation was measured by net increases in bone length, volume, and mass of matrix and mineral. Experimental bones had a significantly smaller volume and mass. Bone resorption was much ...

1983-01-01

71

Carbon dioxide absorption mechanisms of sodium added to calcium oxide at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

To apply the CO{sub 2} absorber at about 1000{sup o}C for integrated coal gasification combined cycle (IGCC) furnace, the reactions of calcium oxide and CO{sub 2} at high temperatures was examined. Calcium carbonate reacts with sodium hydrogen carbonate below 200{sup o}C and forms sodium-calcium complex carbonate. The sodium-calcium complex carbonate melts at 813{sup o}C, and the carbon dioxide absorption and discharge reversible reactions of calcium-oxide takes place via liquid at around 1000{sup o}C. Sintering of calcium oxide at high temperature has been successfully avoided by the addition of sodium.

2004-07-01

72

Protective role of selenium against renal toxicity induced by cadmium in rats  

International Nuclear Information System (INIS)

Cadmium is an environmental toxic metal implicated in human diseases. The mechanism of its toxicity is not fully understood. Therefore, the role of cadmium in renal toxicity, and the protective role of selenium against this toxicity were investigated. Forty-five male rats were used through out the study and divided into three groups of 15. The first group received saline solution daily for 10 days. The second group, received cadmium chloride (CdCl_2) (2 mg/kg body weight) intraperitoneally daily for a period of 10 days. The third group, received sodium selenite (1 mg/kg body weight, twice a day) and CdCl_2 (once a day) for a period of 10 days. The results showed that cadmium treatment increased renal lipid peroxidation (measured as malondialdehyde, MDA) which was associated with a significant decrease in the antioxidant systems such as reduced glutathione levels and the activities of glutathione ...

2007-06-25

73

In vivo effects of cadmium chloride on certain aspects of carbohydrate metabolism in the tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Cadmium is a toxic, non-essential heavy metal inhibiting numerous enzymes with functional sulfhydryl groups. Among the animals, aquatic organisms are most sensitive to heavy metals. Various aspects of toxic effects of cadmium pollution on fishes have been extensively reviewed. Survey of literature reveals that relatively few attempts have been made on the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, received less attention. This crab forms one of the major components of the paddy field ecosystem and has an edible importance among local populations. Apart from this, these crabs are easily available, maintainable in the laboratory and data obtained in this study can be extrapolated to other crustaceans. The present study reports the influence of cadmium on ...

1989-06-01

74

Plasmid-conferred tetracycline resistance confers collateral cadmium sensitivity to E. coli cells  

Energy Technology Data Exchange (ETDEWEB)

E. coli HB101 cells transformed to tetracycline resistance with the plasmids pMB9 or pBR322 display a 10/sup 5/-10/sup 6/-fold lower plating efficiency on agar containing 440 ..mu..M CdCl/sub 2/ than nontransformed cells. When DNA is inserted into the BamH1 site of the plasmid tet gene, or when DNA spanning the BamH1 site is deleted, tetracycline resistance and cadmium hypersensitivity are both lost. In contrast, insertion of DNA into the ampicillin resistance gene does not affect cadmium hypersensitivity.

1982-01-01

75

Cadmium and endrin toxicity to fish in waters containing mineral fibers  

Energy Technology Data Exchange (ETDEWEB)

Taconite tailings and their component asbestiform minerals in Lake Superior water had no demonstrable effect on the chronic toxicity of cadmium to the flagfish, Jordanella floridae. Maximum acceptable toxicant concentrations determined in life cycle tests, where effects on survival, growth, reproduction, and bioconcentration were used as endpoints, were between 3.3 to 7.4, 3.0 to 6.5, and 3.4 to 7.3 micrograms cadmium/liter at 0.004, 0.08, and 0.95 mg/liter taconite tailings concentrations, respectively.

1982-05-01

77

Optical and Structural Characteristics of Heavily Boron ...  

Science.gov (United States)

... Abstract : Cadmium telluride single crystals were subjected to multiple-energy boron ion implants with total doses up to 1.5 x 10 sq cm. ...

1988-05-24

79

Cadmium inhibits neurogenesis in zebrafish embryonic brain development  

International Nuclear Information System (INIS)

Cadmium is a non-essential heavy metal found abundantly in the environment. Children of women exposed to cadmium during pregnancy display lower motor and perceptual abilities. High cadmium body burden in children is also related to impaired intelligence and lowered school achievement. However, little is known about the molecular and cellular basis of developmental neurotoxicity in the sensitive early life stages of animals. In this study, we explore neurological deficits caused by cadmium during early embryonic stages in zebrafish by examining regionalization of the neural tube, pattern formation and cell fate determination, commitment of proneural genes and induction of neurogenesis. We show that cadmium-treated embryos developed a smaller head with unclear boundaries between the brain subdivisions, particularly in the mid-hindbrain region. Embryos display normal anterior to ...

2008-05-01

80

Update on the oxidative stress theory of aging: Does oxidative stress play a role in aging or healthy aging?  

UK PubMed Central (United Kingdom)

The oxidative stress theory of aging predicts that manipulations that alter oxidative stress/damage will alter aging. The gold standard for determining whether aging is altered is lifespan,...Full Text Available

2010-03-01

81

The Importance of Mitochondrial DNA in Aging and Cancer  

UK PubMed Central (United Kingdom)

Mitochondrial dysfunction has been implicated in premature aging, age-related diseases, and tumor initiation and progression. Alterations of the mitochondrial genome accumulate both in aging tissue...Full Text Available

82

Mitochondria and PGC-1? in Aging and Age-Associated Diseases  

UK PubMed Central (United Kingdom)

Aging is the most significant risk factor for a range of degenerative disease such as cardiovascular, neurodegenerative and metabolic disorders. While the cause of aging and its associated diseases...Full Text Available

84

The role of calcium ions and calcium channel entry blockers in experimental ischemia-reperfusion-induced liver injury.  

UK PubMed Central (United Kingdom)

Verapamil administered before treatment, but not after treatment, had a beneficial effect on a 90-minute warm ischemia-reperfusion rat liver injury model. The possible activation of proteases converting...Full Text Available

1991-02-01

85

The Functional Role of Calcineurin in Hypertrophy, Regeneration, and Disorders of Skeletal Muscle  

UK PubMed Central (United Kingdom)

Skeletal muscle uses calcium as a second messenger to respond and adapt to environmental stimuli. Elevations in intracellular calcium levels activate calcineurin, a serine/threonine phosphatase, resulting...Full Text Available

2010-01-01

86

Strategies for the uses of lanthanide NMR shift probes in the determination of protein structure in solutio. Application to the EF calcium binding site of carp parvalbumin.  

UK PubMed Central (United Kingdom)

The homologous sequences observed for many calcium binding proteins such as parvalbumin, troponin C, the myosin light chains, and calmodulin has lead to the hypothesis that these proteins have homologous...Full Text Available

1980-10-01

87

Modulation of B-cell endoplasmic reticulum calcium homeostasis by Epstein-Barr virus Latent Membrane Protein-1  

UK PubMed Central (United Kingdom)

BackgroundCalcium signaling plays an important role in B lymphocyte survival and activation, and is critically dependent on the inositol-1,4,5-tris-phosphate-induced...Full Text Available

88

Mapping the Spatiotemporal Dynamics of Calcium Signaling in Cellular Neural Networks Using Optical Flow  

UK PubMed Central (United Kingdom)

An optical flow gradient algorithm was applied to spontaneously forming networks of neurons and glia in culture imaged by fluorescence optical microscopy in order to map functional calcium signaling...Full Text Available

2010-08-01

89

Hair Mercury Negatively Correlates with Calcium Pump Activity in Human Term Newborns and Their Mothers at Delivery  

UK PubMed Central (United Kingdom)

BackgroundCalcium homeostasis is a known target of several environmental toxicants including lead and mercury.ObjectiveOur goal was to determine...Full Text Available

2008-02-01

90

Ethoxylated Bisphenol Dimethacrylate-based Amorphous Calcium Phosphate Composites  

UK PubMed Central (United Kingdom)

Improving the anti-demineralizing/remineralizing and mechanical properties of amorphous calcium phosphate (ACP) composites has been the focus of our recent research. In this study, an ethoxylated...Full Text Available

2006-01-01

91

Effects of calcium supplementation on bone density in healthy children: meta-analysis of randomised controlled trials  

UK PubMed Central (United Kingdom)

Objectives To assess the effectiveness of calcium supplementation for improving bone mineral density in healthy children and to determine if any effect is modified by other factors and...Full Text Available

2006-10-14

92

Detrusor overactivity is associated with downregulation of large-conductance calcium- and voltage-activated potassium channel protein  

UK PubMed Central (United Kingdom)

Large-conductance voltage- and calcium-activated potassium (BK) channels have been shown to play a role in detrusor overactivity (DO). The goal of this study was to determine whether bladder outlet...Full Text Available

2010-06-01

93

Calcium, Vitamin D, VDR Genotypes, and Epigenetic and Genetic Changes in Rectal Tumors  

UK PubMed Central (United Kingdom)

Calcium, vitamin D, exposure to sunshine, and vitamin D receptor (VDR) genotypes have been associated rectal cancer. We used data from 750 rectal tumors and 1,205 population-based...Full Text Available

2010-05-01

94

Calcium - blood test: MedlinePlus Medical Encyclopedia  

Science.gov (United States)

Names Ca+2; Serum calcium; Ca++ References Wysolmerski JJ, Insogna KL. The parathyroid glands, hypercalcemia, and hypocalcemia. In: Goldman L, Ausiello D, eds. Cecil...

2011-08-30

95

A Comparison between Quin-2 and Aequorin as Indicators of Cytoplasmic Calcium Levels in Higher Plant Cell Protoplasts 1  

UK PubMed Central (United Kingdom)

Assessment of the regulation of plant metabolism by the calcium ion requires a knowledge of its intracellular levels and dynamics. Technical problems have prevented direct measurement of the concentration...Full Text Available

1989-06-01

96

17?-estradiol regulation of T-type calcium channels in gonadotropin-releasing hormone neurons  

UK PubMed Central (United Kingdom)

T-type calcium channels are responsible for generating low-threshold spikes that facilitate burst firing and neurotransmitter release in neurons. GnRH neurons exhibit burst firing, but the underlying...Full Text Available

2009-08-26

97

Separation and determination of cadmium and zinc as their thenoyltrifluoroacetone complexes with dibenzo-18-crown-6 by means of synergistic extraction and atomic absorption spectrometry  

Energy Technology Data Exchange (ETDEWEB)

A new method for the separation and determination of trace amounts of cadmium and zinc in water as their thenoyltrifluoroacetone (TTA) complexes with dibenzo-18-crown-6 (DB18C6) in o-dichlorobenzene has been established by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry. The effect of various factors (synergism with TTA and DB18C6, shaking time, composition of the extracted species, and mutual separation etc.) on the extraction and back-extraction of cadmium and zinc has been in- vestigated. When the mixtures were extracted for 4 min at pH 4.9, only zinc was extracted quantitatively, whereas cadmium remained in the aqueous phase. After the phases were separated, cadmium was again extracted quantitatively at pH 7.5. Then, the two phases were each shaken with 0.05-0.1 mol/l HCl in order to back-extract cadmium and zinc from the organic ...

1997-01-01

98

Root-to-shoot Cd translocation via the xylem is the major process determining shoot and grain cadmium accumulation in rice  

UK PubMed Central (United Kingdom)

Physiological properties involved in divergent cadmium (Cd) accumulation among rice genotypes were characterized using the indica cultivar ‘Habataki’ (high Cd in grains)...Full Text Available

2009-07-01

99

Peculiarity of counterion - polyion interactions in aqueous solutions of copolymers of acrylamide with cadmium acrylate  

Energy Technology Data Exchange (ETDEWEB)

Binding of Cd/sup 2 +/ ions in aqueous solutions of statistical copolymers of acrylamide with cadmium acrylate with different content of ionogenic groups in copolymers was investigated by polarography, conductometry, viscometry and dialysis. It is shown that the degree of binding of Cd/sup 2 +/ ions increases with increasing of the content of ionogenic groups in the copolymer and with decreasing of ionic strength of the solution. The values of the degree of binding of Cd/sup 2 +/ ions obtained by polarography and dialysis show satisfactory agreement.

1984-02-01

100

A System-Based Comparison of Gene Expression Reveals Alterations in Oxidative Stress, Disruption of Ubiquitin-Proteasome System and Altered Cell Cycle Regulation after Exposure to Cadmium and Methylmercury in Mouse Embryonic Fibroblast  

UK PubMed Central (United Kingdom)

Environmental and occupational exposures to heavy metals such as methylmercury (MeHg) and cadmium (Cd) pose significant health risks to humans, including neurotoxicity. The underlying mechanisms of...Full Text Available

2010-04-01

102

Smoke Compositions Based on Phosphorus  

Science.gov (United States)

... Both magnesium and aluminium phosphides are therefore potentially more efficient than either calcium or sodium phosphide. ...

1958-03-01

103

Proceedings of ARO Workshop Biostructures as Composite ...  

Science.gov (United States)

... interactive surfaces and interfaces, and 3) the more complex a ... carbonate or calcium phosphate with a thin interface ... diameter) for nerve prosthesis. ...

1990-03-01

104
105

Well preflush fluid  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a preflush fluid for preventing lost circulation during the cementing of a well, the fluid consisting essentially of: (a) water; (b) about 10 to about 30 percent by weight of water (% BWOW) cement; (c) about 5 to about 30% BWOW calcium sulfate selected from the group consisting of calcium sulfate hemihydrate, calcium sulfate dihydrate, and mixtures thereof; and (d) an alkali metal-containing quick-hardening accelerator.

1992-01-21

106

Removal of noxious contaminants from gas  

Science.gov (United States)

Gas contaminated with at least one noxious component, such as SO/sub 2/, HF or NOx, is scrubbed with a clear, calcium-containing, initially-basic washing liquid which also comprises the anion of a strong inorganic acid, that of a polybasic carboxylic acid and, optionally, that of a monobasic carboxylic acid. Apparatus is provided for scrubbing the gas, oxidizing produced calcium bisulfite to calcium sulfate, separating out and removing solids, and recirculating clarified liquid for scrubbing contaminated gas.

1980-09-16

107

Calcium fluoride window mounting  

International Nuclear Information System (INIS)

A technique has been developed for joining a large calcium fluoride crystal to a stainless-steel flange by means of a silver transition ring. The process involves both vacuum brazing using a copper-silver alloy and air brazing using silver chloride. This paper describes the procedure used in fabricating a high-vacuum leak-tight calcium fluoride window assembly.

109

Emerging technologies for academic libraries in the digital age  

CERN Document Server

Emerging technologies for academic libraries in the digital age

2009-01-01

110

Characterization of the product of the thiosulfate process for desulfurization of flue gases  

Energy Technology Data Exchange (ETDEWEB)

X-ray diffraction, infrared spectroscopy, thermal analysis, scanning electron microscopy, and particle size analysis were used to characterize the product of the thiosulfate process. It was found to consist of a mixture of a solid solution of calcium sulfate in calcium sulfite hemihydrate, calcium sulfate dihydrate, and calcium carbonate. Reactions taking place on heating the byproduct were identified in oxidizing and reducing atmospheres. Pure calcium sulfite hemihydrate as well as solid solutions of CaSO[sub 4] in CaSO[sub 3] [center dot] (1/2)H[sub 2]O with different sulfate concentrations were synthesized in the laboratory. Thermal analyses of pure solid solutions proved that the higher the sulfate content, the higher is the dehydration temperature. Accordingly, taking SO[sub 4][sup 2[minus

1994-05-01

111

Enrichment of trace cadmium by soybean protein for the analysis by atomic absorption method  

International Nuclear Information System (INIS)

A method for enrichment of the ppb level of cadmium in water by using the coagulation of soybean protein by adding acids or its complex-forming character with heavy metal ions was investigated. After adding fixed amounts of soybean milk and 2% sodium diethyldithiocarbamate(DDTC) aqueous solution and a suitable amount of delta-gluconic lactone (delta-GL) to a sample solution, the mixture was heated to boiling in order to coagulate the protein. The coagulum(soybean curd) was separated from the suspension by centrifugation and burned to ashes with a low temperature plasma asher. Then the cadmium enriched in it was determined by atomic absorption spectrometry. Various factors such as the pH of the sample solution, the amounts of soybean milk and the collection additives, and the concentration of NaCl in the sample solution on the recovery of cadmium were examined systematically. The best recovery was obtained under the ...

1975-01-01

112

Investigation of flora and fauna species of Lake Baikal by electron-probe microanalysis  

International Nuclear Information System (INIS)

Complete text of publication follows. Baikal is an ancient unique lake. The sweet water of Baikal is crystal clean; it concentrates oxygen and contains scarce silicon. This feature is provoked very particular interest for scientists and poses some awkward questions concerning the preservation of Baikal's ecosystem. A profound investigation of fish otholiths, animal teeth, sponges, valves of mollusks and diatom algae provides chronological information, possibility to reconstruct the events proceeding in the environment based on variations of their chemical composition. Because these study objects are small-sized, and some of them are micron-size, application of the electron-probe microanalysis turns to be quite productive. The goal of this study is to disclose performance capabilities of this method while investigating the Baikal flora and fauna. Investigations were performed by devices JCXA-733 and JXA-8200 using the electron microscope and x-ray microprobe modes. Measurements of ...

113

Long-distance transport, vacuolar sequestration, tolerance, and transcriptional responses induced by cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential metals, at high concentrations, and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and rec...

2011-01-01

114

Lead, cadmium, chromium, cobalt, and copper in chicken feathers from Tuskegee, Alabama  

Energy Technology Data Exchange (ETDEWEB)

The feather has been widely used as a indicator tissue of metal exposure in birds. The feathers were collected from Tuskegee University poultry farm (TUPF) and Harrison Poultry farm (HPF) chicken and analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy for lead, cadmium, cobalt, chromium, and copper contaminations. The mean levels of lead, cadmium, cobalt, chromium, and copper in TUPF chicken were 3.67, 0.13, 12.23, 0.22, and 7.71 ppm, respectively, and in HPF chicken were 5.32, 0.096, 11.03, 0.15, and 8.06 ppm, respectively. The mean levels of these metals did not show any significant difference between TUPF and HPF chicken.

1994-12-31

115

Canadian soil quality criteria for lead, copper, arsenic, cadmium and mercury  

Energy Technology Data Exchange (ETDEWEB)

National soil quality criteria for the protection of ecological receptors, including livestock and wildlife, are currently under development in Canada. Based on an evaluation of direct soil contact and soil and food ingestion pathways for sensitive species, soil quality criteria for lead, copper, arsenic, cadmium and mercury for three land use categories have been derived. The draft values, in mg/kg soil, for agricultural, residential/parkland, commercial/industrial land uses are: mercury, 4, 4, 30; copper, 62, 62, 100; cadmium, 10, 10, 27; lead, 70, 250, 400; arsenic, 17, 17, 26. Critical data requirements in developing soil quality criteria are also reviewed.

1995-12-31

116

Uptake, transport, and storage of calcium and magnesium in spruce (Picea abies [L]Karst.) and pine (Pinus silvestris L.) as affected by variable nutrition and pollutant stress  

International Nuclear Information System (INIS)

Statements about the dynamic processes of uptake, transport, and deposition of Ca and Mg in norway spruce and Scots pine are made in this paper. Concerning the storage of these elements it is shown that there are great differences in their functional importance in cell metabolism. There is evidence that the role of Mg in enzyme and protein metabolism is of far greater significance for the understanding of Mg-deficiency symptoms than its function as the central atom of the chlorophyll complexes. In regard to the transport and especially to the incorporation of Ca into the needles differences between species were evident, expressing the special status of pine among the gymnosperms. With increasing needle age an accumulation of Ca-oxalate crystals, which are physiologically inert, could be proved for the studied conifers. This was interpreted as a 'detoxication' from surplus Ca to hold constant the level of the physiologically active fraction. Accordingly, the low ...

117

WHAT OLD MEANS TO BONE  

UK PubMed Central (United Kingdom)

The adverse effects of aging of other organs (ovaries at menopause) on the skeleton are well known, but ironically little is known of skeletal aging itself. Evidence indicates that age-related...Full Text Available

2010-06-01

118

Healthy aging and disease: role for telomere biology?  

UK PubMed Central (United Kingdom)

Aging is a biological process that affects most cells, organisms and species. Human aging is associated with increased susceptibility to a variety of chronic diseases, including cardiovascular disease,...Full Text Available

2011-05-01

119

Age Preservation of the Syntactic Processor in Production  

UK PubMed Central (United Kingdom)

Two experiments are reported on the influence of cognitive aging on grammatical choice in language production. In both experiments, participants from two age-groups (young and old) produced...Full Text Available

2003-09-01

120

Thin Film Solar Cells and Solar Cell Testing, Volume II Proceedings of the Fourth Photovoltaic Specialists Conference  

Science.gov (United States)

Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells

1964-01-01

121

Phytochelatin Synthesis and Glutathione Levels in Response to Heavy Metals in Tomato Cells 1  

UK PubMed Central (United Kingdom)

Cell suspension cultures of tomato, Lycopersicon esculentum Mill. cv VFNT-Cherry, produce phytochelatins (poly[γ-glutamylcysteinyl]glycines) when exposed to cadmium. The synthesis...Full Text Available

1987-12-01

122

Partial Characterization of Cadmium-Binding Protein from Roots of Tomato 1  

UK PubMed Central (United Kingdom)

Cd-binding protein was extracted from tomato roots and purified on QAE-Sephadex A-25 and on Sephadex G-75 in 1 molar KCl buffer. The protein preparation was light brown and contained predominantly Cd...Full Text Available

1986-07-01

123

Optical and Structural Characteristics of Heavily Boron-Implanted CdTe.  

Science.gov (United States)

Cadmium telluride single crystals were subjected to multiple-energy boron ion implants with total doses up to 1.5 x 10 sq cm. Various diagnostic techniques were used to assess the structural and electronic properties of these crystals in their as-implante...

1988-01-01

124

NREL preprints for the 23rd IEEE Photovoltaic Specialists Conference  

Energy Technology Data Exchange (ETDEWEB)

Topics covered include various aspects of solar cell fabrication and performance. Aluminium-gallium arsenides, cadmium telluride, amorphous silicon, and copper-indium-gallium selenides are all characterized in their applicability in solar cells.

1993-05-01

125

Cadmium biosorption rate in protonated Sargassum biomass  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of the heavy metal ion Cd{sup 2+} by protonated nonliving brown alga Sargassum fluitans biomass was accompanied by the release of hydrogen protons from the biomass. The uptake of cadmium and the release of proton matched each other throughout the biosorption process. The end-point titration methodology was used to maintain the constant pH 4.0 for developing the dynamic sorption rate. The sorption isotherm could be well represented by the Langmuir sorption model. A mass transfer model assuming the intraparticle diffusion in a one-dimensional thin plate as a controlling step was developed to describe the overall biosorption rate of cadmium ions in flat seaweed biomass particles. The overall biosorption mathematical model equations were solved numerically yielding the effective diffusion coefficient D{sub e} about 3.5 {times} 10{sup {minus}6} cm{sup 2}/s. This value matches that obtained for the desorption process and is approximately ...

1999-03-01

126

Assessment of battery technologies for electric vehicles  

Energy Technology Data Exchange (ETDEWEB)

This document, Part 2 of Volume 2, provides appendices to this report and includes the following technologies, zinc/air battery; lithium/molybdenum disulfide battery; sodium/sulfur battery; nickel/cadmium battery; nickel/iron battery; iron/oxygen battery and iron/air battery. (FI)

1990-02-01

127

Synthesis of histidine-stabilized cadmium sulfide quantum dots: Study of their fluorescence behaviour in the presence of adenine and guanine  

British Library Electronic Table of Contents (United Kingdom)

Cadmium sulfide particles have been synthesized in the aqueous medium using the amino acid histidine as a stabilizing agent. These particles demonstrate the phenomenon of size quantization effect. The fluorescence of histidine-stabilized CdS was found to be enhanced and quenched by the addition of DNA bases adenine and guanine, respectively. The fluorescence enhancement of CdS in the presence of adenine has been explained on the basis of interaction between the quantum dot stabilizer and the amino group of adenine. Quenching of CdS fluorescence by guanine occurs due to interaction of the substrate with the quantum dot surface.

2010-01-01

128

Biosorption process for removing heavy metal ions using water milfoil (Myriophyllum Spicatum) in contaminated water  

Energy Technology Data Exchange (ETDEWEB)

A small scale biomass metal contacting experiment was performed to screen the optimal plant species for biosorption and bioaccumulation of cadmium, zinc, nickel, lead, and copper. Experiments were also conducted to test the ability of the biomass to lower the metal concentrations below the US Environmental Protection Agency surface water discharge criteria. The minimum residual concentration was 0.1 mg/L for zinc, 0.004 mg/L for lead, and about 0.01 mg/L for cadmium, nickel, and lead. Results indicate that water milfoil can be used for bioremoval of metals.

1995-12-31

129

ASARCO to pay over $59 million for damages and cleanup costs at Denver smelting facility  

Science.gov (United States)

Since 1901, ASARCO, Inc. has owned and operated an 89-acre cadmium-refining smelter in the Globeville neighborhood of north Denver, Colorado. According to complaints filed by EPA and local residents, operations at the smelter have allegedly contaminated the air, ground water, surface water, and soil; contamination from arsenic, cadmium, lead, and zinc has occurred both onsite and offsite. EPA proposed to add the site to the National Priorities List (NPL) in May 1993.

1993-11-01

130

Process development for production of coal/sorbent agglomerates. Final technical report, September 1, 1990--August 31, 1991  

Energy Technology Data Exchange (ETDEWEB)

The goal of this work was to develop a process flow diagram to economically produce a clean-burning fuel from fine Illinois coal. To accomplish this, the process of pelletizing fine coal with calcium hydroxide, a sulfur capturing sorbent, was investigated. Carbonation, which is the reaction of calcium hydroxide with carbon dioxide (in the presence of moisture) to produce a bonding matrix of calcium carbonate, was investigated as a method for improving pellet quality and reducing binder costs. Proper moisture level is critical to allow the reaction to occur. If too much moisture is present in a pellet, the pore spaces are filled and carbon dioxide must diffuse through the water to reach the calcium hydroxide and react. This severely slows or stops the reaction. The ideal situation is when there is just enough moisture to coat the calcium hydroxide allowing for the reaction to ...

1991-12-31

131

Method of treating final products from flue gas desulfurization  

Science.gov (United States)

A method of treating final products from a flue gas desulfurization. The flue gas desulfurization is carried out by the absorption of sulfur oxide in a spray dryer with a suspension which contains lime, or in a reactor with a dry, fine-grained, absorbent which contains lime. Prior to desulfurization, the fly ash carried along by the flue gas which is to be desulfurized is separated entirely, partially, or not at all from the flue gas, and the final products from the flue gas desulfurization, prior to any further treatment thereof, amount to 1-99% by weight, preferably 1-70% by weight, of fly ash, and 1-99% by weight, preferably 30-99% by weight, of the sum of the desulfurization products, preferably calcium sulfite hemihydrate, and/or calcium sulfite, and/or calcium sulfate dyhydrate, and/or calcium sulfate hemihydrate, and/or calcium sulfate, as well as residue of the absorbent. ...

1984-10-23

132

Wet limestone FGD solids analysis by thermogravimetry  

Energy Technology Data Exchange (ETDEWEB)

Wet limestone scrubbing is once again becoming a popular technology for removal of sulfur dioxide (SO{sub 2}) from power plant emissions. Critical to the operation of wet limestone flue gas desulfurization (FGD) systems is accurate chemical analysis of scrubber solids. The analytical technique of thermogravimetry is ideal for this application, as the instrument can give precise readings of the principal scrubber solids components, calcium sulfite/sulfate hemihydrate, calcium sulfate dihydrate (gypsum), and unused calcium carbonate. The data provides plant chemists, engineers, and operators with information needed to fine-tune scrubber operation and detect process upsets. (orig.)

2004-07-01

134

Vitamin D and respiratory health  

UK PubMed Central (United Kingdom)

Vitamin D is now known to be of physiological importance outside of bone health and calcium homeostasis, and there is mounting evidence that it plays a beneficial role in the prevention and/or treatment...Full Text Available

2009-10-01

135

Two-photon calcium imaging from head-fixed Drosophila during optomotor walking behavior  

British Library Electronic Table of Contents (United Kingdom)

Drosophila melanogaster is a model organism rich in genetic tools to manipulate and identify neural circuits involved in specific behaviors. Here we present a technique for two-photon calcium imaging in the central brain of head-fixed Drosophila walking on an air-supported ball. The ball's motion is tracked at high resolution and can be treated as a proxy for the fly's own movements. We used the genetically encoded calcium sensor, GCaMP3.0, to record from important elements of the motion-processing pathway, the horizontal-system lobula plate tangential cells (LPTCs) in the fly optic lobe. We presented motion stimuli to the tethered fly and found that calcium transients in horizontal-system neurons correlated with robust optomotor behavior during walking. Our technique allows both behavior ...

2010-01-01

136

Transformation of Verapamil by Cunninghamella blakesleeana  

UK PubMed Central (United Kingdom)

A filamentous fungus, Cunninghamella blakesleeana AS 3.153, was used as a microbial model of mammalian metabolism to transform verapamil, a calcium channel antagonist. The metabolites...Full Text Available

2004-05-01

138

Role of temperature in the spontaneous precipitation of calcium sulfate dihydrate  

Energy Technology Data Exchange (ETDEWEB)

The spontaneous precipitation of calcium sulfate in supersaturated solutions over the temperature range between 25.0 and 80.0 C was investigated by monitoring the solution specific conductivity during desupersaturation. From measurements of the induction times preceding the onset of precipitation the surface energy of the forming solid, identified as gypsum, was found between ca. 12 and 25 mJ/m{sup 2} for the temperature range between 80.0 and 25.0 C, respectively. Kinetics analysis showed that over 50 C it is possible that anhydrous calcium sulfate is forming as a transient phase converting into the more stable calcium sulfate dihydrate. The linear dependence of the rates of precipitation on the relative solution supersaturation suggested a mechanism according to which the growth units are integrated into the active sites of the supercritical nuclei by surface diffusion. According to the morphological examination of the ...

1999-02-16

139

Mechanisms of Reproductive Thermotolerance in Gossypium hirsutum: The Effect of Genotype and Exogenous Calcium Application  

British Library Electronic Table of Contents (United Kingdom)

Abstract Although photosynthetic thermotolerance has been investigated extensively in cotton leaves, reports on the biochemical influence of the pistil in promoting fertilization thermostability are limited. To evaluate the effect of temperature, genotype, and exogenous calcium application on fertilization and pistil biochemistry in cotton, thermosensitive (cv. ST4554 B2RF) and thermotolerant (cv. VH260) plants were grown under control (30/20-C) or high-temperature (38/20-C) conditions during flowering, and exogenous CaCl2 was applied to flowers 1-day prior to anthesis. Measured pistil parameters included fertilization efficiency; protein concentration; glutathione reductase, superoxide dismutase (SOD) and NADPH oxidase activities; and ATP and calcium levels. Exogenous calcium had no effec...

2011-01-01

140

Loss of Skeletal Calcium by Patients on Maintenance Dialysis  

UK PubMed Central (United Kingdom)

Direct radiological measurements of the mineral content of femoral bone were performed in 13 patients on maintenance dialysis. They were found to be sufficiently sensitive to be used for monitoring,...Full Text Available

1970-08-29

141

Instrumental-activation analysis of Mo, Al, Ca, Mn, Cl, Na, and K in soil-plant samples  

International Nuclear Information System (INIS)

... activation analysis aluminium 28 calcium 49 chlorine 38 cotton plants li-drifted

142

Effects of manganese doping on properties of sol-gel derived biphasic calcium phosphate ceramics  

British Library Electronic Table of Contents (United Kingdom)

We have investigated the effect of manganese (Mn) doping on properties of nanosized biphasic calcium phosphate powders and their dense bodies. Manganese levels of 0.6, 1.3, 1.9, 4.3, 7.0 and 11.9at.% were successfully incorporated into biphasic calcium phosphate via a sol-gel route. The prepared powders were calcined at temperatures of 500-1200^oC. The X-ray diffraction analysis revealed that a mix phase comprising of hydroxyapatite and @b-tricalcium phosphate were present, however the content of each phases in the structure was affected by the Mn content. The studies found that the largest portion of @b-tricalcium phosphate was detected at 4.3at.% Mn doping. The incorporation of Mn has also greatly increased the crystallinity of the biphasic calcium phosphate powder due to progressive den...

2011-01-01

143

Cleaning Aged EPDM Rubber Roofing Membrane Material for ...  

Science.gov (United States)

... 5. The results of the bond strength measurements were compared to the surface cleanness of the aged EPDM as determined by the specified ...

1992-08-01

144

Lead and cadmium in food. How do heavy metals find their way into our food and, how can the general public protect itself; Blei und Cadmium in Lebensmitteln; Wie kommen die Schwermetalle in unsere Nahrung? Und: Wie koennen sich Verbraucherinnen und Verbraucher schuetzen?  

Energy Technology Data Exchange (ETDEWEB)

The amounts of lead and cadmium produced and processed in these days are considerable. As a result, our environment is increasingly polluted by heavy metals and industrial installations, motor vehicles or incinerating plants appear to be among the main culprits here. Air and water are the media permitting the entry of heavy metals into our natural environment where they accumulate in the soil and then gradually migrate into the plants. Their further transport in the food constitutes the third step in the environmental spread of heavy metals. The consumption of muscle and organ meats, of vegetables, fruits, canned food and drinking water is unavoidably associated with some ingestion of lead and cadmium. The degree to which they are taken up and stored in different tissues is determined by absorption properties and the nutritional state of the organism. Cadmium tends to accumulate in the kidneys, lead is mainly stored in the ...

1992-08-01

145

The effects of a calcium deficient diet on the mechanical properties and morphology of goose bone.  

Science.gov (United States)

A control group of geese (Anser anser) on a normal calcium diet for egg laying poultry was compared to egg laying geese on a calcium deficient diet. The ultimate compressive strength and modulus of elasticity of femoral cortical bone from each group were determined by compressing right circular cylinders which were 2.4 mm in height and 0.8 mm in diameter. The bending strength and bending modulus of elasticity of tibial cortical bone were determined by three point bend tests on rectangular prisms which were approximately 25 mm by 0.8 mm by 0.8 mm. Bone calcium content and eggshell calcium content were determined by atomic absorption spectrophotometry. Blood samples were analyzed for free calcium ion concentration. Histological observations included studies of cross-sectional microradiographs, examinations of cross sections stained by a modified Masson's technique, and a determination ...

1986-01-01

146

Selective Expression in Carotid Body Type I Cells of a Single Splice Variant of the Large Conductance Calcium- and Voltage-activated Potassium Channel Confers Regulation by AMP-activated Protein Kinase*  

UK PubMed Central (United Kingdom)

Inhibition of large conductance calcium-activated potassium (BKCa) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BKCa channels remain active...Full Text Available

2011-04-08

147

Physicochemical basis for formation of renal stones of calcium phosphate origin: calculation of the degree of saturation of urine with respect to brushite  

UK PubMed Central (United Kingdom)

Brushite (CaHPO4·2H2O) was considered to govern the formation of renal calculus of calcium phosphate origin. The degree of saturation of urine with respect to this phase...Full Text Available

1969-10-01

148

Effects of xylitol on the absorption of /sup 203/Pb in mice and cockerels  

Energy Technology Data Exchange (ETDEWEB)

Earlier studies have indicated that xylitol may increase the absorption and urinary excretion of dietary oxalate. It has also been indicated that xylitol increases the absorption of calcium. Intestinal absorption of lead, a divalent contaminant in the diet, is in many respects similar to that of calcium. The purpose of this study was to evaluate the effects of xylitol on the intestinal absorption of lead using two different approaches: the in situ ligated intestinal loop technique in cockerels and gastric gavage in mice.

1986-07-01

149

Solid-gas equilibria in CaSO/sub 3/-H/sub 2/O/sub (g)/ system and Lewis-acid-base alloys  

Energy Technology Data Exchange (ETDEWEB)

The role played by calcium sulfite in the flue gas desulfurization of lime/limestone scrubbers makes it desirable to work out its thermodynamic properties. A thermogravimetric apparatus was used to study the equilibria between calcium sulfite hemihydrate and calcium sulfite anhydrite under different conditions. Efforts were made to analyze the difficulties encountered in the dynamic approach to equilibration after calcium sulfate dihydrate failed in calibration of the apparatus. Finally, the kinetics and thermodynamics for the dissociation of calcium sulfite hemihydrate were examined. The confirmation of Engel-Brewer's correlation between the electronic configuration and crystal structure in metallic systems has long been pursued in this group by studying the Lewis-acid-base interactions. Tantalum-iridium alloys of different compositions were brought into equilibrium with ...

1981-10-01

150

Human complement protein C99 is a calcium binding protein  

International Nuclear Information System (INIS)

Human complement protein C9 is shown to be a metalloprotein that binds 1 mol of Ca"2"+/mol of C9 with a dissociation constant of 3 #mu#m as measured by equilibrium dialysis. Incubation with EDTA removes the bound calcium, resulting in a apoprotein with decreased thermal stability. This loss in stability leads to aggregation and, therefore, to loss of hemolytic activity upon heating to a few degrees above the physiological temperature. Heat-induced aggregation of apoC9 can be prevented by salts that stabilize proteins according to the Hofmeister series of lyotropic ions, suggesting that the ion in native C9 may ligand with more than one structural element of domain of the protein. Ligand blotting indicates that the calcium binding site is located in the amino-terminal half of the protein. Removal of calcium by inclusion of EDTA in assay mixtures has no effect on the hemolytic activity of C9, and its capacity to bind to C8 in ...

151

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2-pyridilazo)-resorcin and 2-aminopyridine  

International Nuclear Information System (INIS)

Extraction of copper-, nickel-, zinc- and cadmium complexes with 4-(2 pyridilazo)-resorcin (PAR) is studied in the presence of 2-aminopyridine (Am). Maximum optical densities of the extracts are attained at pH=7.5-8.0; 6.0-7.0; 6.5-7.0 and 7.0-8.0, respectively. The ratio of components in the complexes extractable by chloroform was defined by the method of isomolar series and equilibrium shift. It is established that nickel and copper are extracted to the organic phase as the NiAm(PAR)_2 and CuAmPAR complexes, and, in the case of zinc and cadmium, complexes of different composition are extracted, for example Zn(Am)_2PAR and ZnAm(PAR)_2. The light absorption spectra are studied and molar extinction coefficients of complex extracts are determined at lambdasub(max). It is shown that the general low of light absorption is observed within a sufficiently wide range of concentrations for all the elements.

1984-01-01

152

Enhanced cadmium cytotoxicity in A549 cells with reduced glutathione levels is due to neither enhanced cadmium accumulation nor reduced metallothionein synthesis  

International Nuclear Information System (INIS)

Glutathione (GSH) depletion sensitizes human lung carcinoma (A549-T27) cells to the cytotoxic effects of Cd++. The effects of GSH depletion on Cd++ accumulation and Cd++-induced metallothionein (MT) content were investigated to determine the possible role of these Cd++ responses in the sensitization process. Cellular GSH was depleted to 20% to 25% of control levels with buthionine sulfoximine (BSO), or diethyl maleate (DEM), respectively. Neither treatment significantly affected Cd++-induced accumulation of exogenous 35s-cysteine into intracellular MT in a dose-dependent fashion. The results indicate that neither enhanced Cd++ accumulation nor reduced MT synthesis plays a primary role in affecting enhanced Cd++ cytotoxicity in A549 cells with reduced GSH levels. Although BSO inhibition of GSH synthesis enhanced MT synthesis, it sensitized the cells to Cd++, which suggests an additive effect of GSH and MT in cadmium cytoprotection. This observation also raises the ...

153

Enhanced biosorptive removal of cadmium from aqueous solutions by silicon dioxide nano-powder, heat inactivated and immobilized Aspergillus ustus  

British Library Electronic Table of Contents (United Kingdom)

Heat inactivated Aspergillus ustus (Asp), silicon dioxide-nano-powder (N Si), and silicon dioxide nano-powder-combined-heat inactivated Aspergillus ustus (N Si Asp) were used to study the biosorption of Cd(II) from aqueous solutions via batch equilibrium technique. Surface characterization and immobilization of the fungal cells on silicon dioxide-nano-powder were examined and confirmed by using FT-IR and ESM analysis. Cadmium biosorption processes were investigated under the effect of pH, contact time, sorbent dosage and initial metal concentration. The three examined sorbents were found to exhibit maximum mmolg^-^1 capacity values in pH 7.0. The maximum determined cadmium capacity by silicon dioxide-nano-powder (N Si) (600mmolg^-^1) was found higher than that exhibited by the heat inactiv...

2011-01-01

154

Small-molecule screen identifies inhibitors of a human intestinal calcium-activated chloride channel.  

Science.gov (United States)

Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance ...

2007-12-14

155

Trace analysis in cadmium telluride by heavy ion induced X-ray emission and by SIMS  

International Nuclear Information System (INIS)

The possibilities of using both selective heavy ion induced X-ray emission and secondary ion mass spectroscopy (SIMS), for the identification of impurities present at low concentrations in cadmium telluride are examined. The relative concentrations of the impurities along CdTe crystals have been determined by exciting the X-ray emission of the elements in several slices with Ar and Kr ions and by comparing the relative characteristic X-ray emission yields. As a consequence of the quasimolecular inner shell ionization mechanism in heavy ion-atom collisions, Ar and Kr ions allow a strong excitation of the main impurities seen by SIMS namely Si, Cl and Ge, As, with only a minor contribution of Cd and Te. From the changes of the concentrations of the various impurities along the crystal, informations about segregation coefficients and compensation can be obtained.

2007-02-01

156

The Effect of Contacts on the Counting Characteristics of Heavily Doped Normal-Type Cadmium-Telluride  

Science.gov (United States)

Cadmium telluride single crystals were grown heavily doped with chloride by the THM method. The resulting crystals were n-type with free carrier concentrations of the order of 10('12)/cm at room temperature. Hall effect studies revealed room temperature mobilities between 30 and 350 cm('2)/v-sec and resistivites between 2 x 10('3) and 10('4) ohm-cm. Studies were made of the gamma and alpha counting characteristics of these crystals with metal, metal-semiconductor, and metal-insulator electrodes. It was found that the MIS and MSS structures resulted in significant improvement over the MS structures in counting, signal-to-noise and energy resolution.

1985-01-01

157

Studies on biosorption and toxicity of heavy metals in bacteria; Untersuchungen zur Biosorption und zur Toxizitaet von Schwermetallen auf Bakterien  

Energy Technology Data Exchange (ETDEWEB)

Biosorption behaviour of and toxic effects of heavy metals in submersed and immobilised microorganisms was studied in batches and in continuous processes in an airlift-recycle reactor. Nickel, cadmium, and zinc were used as heavy metals. (orig./VHE) [Deutsch] Am Beispiel einer Naphthalin-2-sulfonsaeure-abbauenden Kultur wurde das Biosorptionsverhalten und die toxische Wirkung von Schwermetallen auf submerse und immobilisierte Mikroorganismen im Batch-Ansatz und im kontinuierlichen Betrieb in einem Airlift-Schlaufenreaktor untersucht. Als Schwermetalle wurden Nickel, Cadmium und Zink eingesetzt. (orig./VHE)

1993-09-01

158

Studies of crystalline CdZnTe radiation detectors and polycrystalline thin film CdTe for X-ray imaging applications  

CERN Document Server

The development of a replacement to the conventional film based X-ray imaging technique is required for many reasons. One possible route for this is the use of a large area film of a suitable semiconductor overlaid on an amorphous silicon readout array. A suitable semiconductor exists in cadmium telluride and its tertiary alloy cadmium zinc telluride. In this thesis the spectroscopic characteristics of commercially available CZT X- and gamma-radiation detectors are established. The electronic, optical, electro-optic, structural and compositional properties of these detectors are then investigated. The attained data is used to infer a greater understanding for the carrier transport in a CZT radiation detector following the interaction of a high energy photon. Following this a method used to fabricate large area films of CdTe on a commercial scale is described. This is cathodic electrodeposition from an aqueous electrolyte. The theory and ...

2001-01-01

159

Roles of biomarkers in evaluating interactions among mixtures of lead, cadmium and arsenic  

British Library Electronic Table of Contents (United Kingdom)

Human exposure to environmental chemicals is most correctly characterized as exposure to mixtures of these agents. The metals/metalloids, lead (Pb), cadmium (Cd), and arsenic (As), are among the leading toxic agents detected in the environment. Exposure to these elements, particularly at chronic low dose levels, is still a major public health concern. Concurrent exposure to Pb, Cd, or As may produce additive or synergistic interactions or even new effects that are not seen in single component exposures. Evaluating these interactions on a mechanistic basis is essential for risk assessment and management of metal/metalloid mixtures. This paper will review a number of individual studies that addressed interactions of these metals/metalloids in both experimental and human exposure studies with...

2008-01-01

160

Fertilizer amendment for improving the phytoextraction of cadmium by a hyperaccumulator Rorippa globosa (Turcz.) Thell  

British Library Electronic Table of Contents (United Kingdom)

Purpose Two main pathways of phytoremediation of heavy metal-contaminated soils are phytostabilization and phytoextraction. Some soil amendments can strengthen phytostabilization or phytoextraction through either reducing heavy metal bioavailability in soil or increasing the heavy metal accumulation capacity of the hyperaccumulator (enhancing heavy metal concentration or shoot biomass of the hyperaccumulator). Urea and chicken manure are often used as fertilizers. This research will explore their effects on a newly found hyperaccumulator, Rorippa globosa (Turcz.) Thell., phytoremediating cadmium (Cd). Materials and methods Pot culture experiment was conducted to study the accumulation characteristics of R. globosa at different Cd contamination concentrations under one fertilizer level (1?g...

2011-01-01

161

Development of engineering technology basis for pyrometallurgical reprocessing: development of transport technology and pyro-process equipments  

International Nuclear Information System (INIS)

Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 773 K, a salt transport test rig and a metal transport test rig were newly installed in an Ar glove box. Function of the salt transport test rig was confirmed with LiCl-KCl molten salt, and the transport behaviour of molten salt was found to follow that of water. The molten salt/liquid metal contactor for Ln/An separation was newly designed and installed. The test with a single-stage contactor was successful with simulated elements, and a three-stage contactor is now under development. A large-scale electro-refiner with a function to transport molten salt and liquid cadmium were newly designed, and to be installed for demonstration test with simulated materials. (authors)

2006-09-25

162

Biosorption of heavy metals on fungal biomass  

Energy Technology Data Exchange (ETDEWEB)

A method of using fungi in removing heavy metal from wastewater was discussed. Fungi for this purpose can be obtained inexpensively, and on a constant basis from industrial fermentation processes. The biosorption of lead, cadmium and nickel on fungal stock cultures, was investigated. In these experiments, the fungal stock used was Aspergillus niger and Rhizopus stolonfier. Alkali pre-treatment of the fungal biomass improved the metal biosorptive capacity in comparison to live cells. The effect of alkali treatment, however, varied,showing highest biosorptive capacity for lead and least for nickel. Results showed that metal biosorption of metallic ions increased with an increase in pH from 3.2 to 4.0. Equilibrium times of five hours were observed for the biosorption of lead and cadmium, while the equilibrium time for nickel was three hours. 10 refs., 3 tabs., 7 figs.

1996-09-01

163

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

British Library Electronic Table of Contents (United Kingdom)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500?years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected...

2006-01-01

164

Variable Pathogenicity Determines Individual Lifespan in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

A common property of aging in all animals is that chronologically and genetically identical individuals age at different rates. To unveil mechanisms that influence aging variability, we identified markers...Full Text Available

2011-04-01

165

The Human Ageing Genomic Resources: online databases and tools for biogerontologists  

UK PubMed Central (United Kingdom)

SummaryAgeing is a complex, challenging phenomenon that will require multiple, interdisciplinary approaches to unravel its puzzles. To assist basic research on ageing, we developed...Full Text Available

2009-02-01

166

Rethinking the evolutionary theory of aging: Transfers, not births, shape senescence in social species  

UK PubMed Central (United Kingdom)

The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness....Full Text Available

2003-08-05

167

Reduced thermal sensitivity and Nav1.8 and TRPV1 channel expression in sensory neurons of aged mice  

UK PubMed Central (United Kingdom)

Sensory neurons in aging mammals undergo changes in anatomy, physiology and gene expression that correlate with reduced sensory perception. In this study we compared young and aged mice to identify...Full Text Available

2006-06-01

168

Prevalence of Early and Late Age-Related Macular Degeneration in India: The INDEYE Study  

UK PubMed Central (United Kingdom)

Purpose.To estimate the prevalence of early and late age-related macular degeneration (AMD) in India.Methods.Of 7518 people aged 60 years and older...Full Text Available

2010-02-01

169

Comparative and alternative approaches and novel animal models for aging research  

UK PubMed Central (United Kingdom)

This special issue of AGE showcases powerful alternative or unconventional approaches to basic aging research, including the use of exceptionally long-lived animal model species and...Full Text Available

2008-09-01

170

Changes in Androgen Receptor, Estrogen Receptor alpha, and Sexual Behavior with Aging and Testosterone in Male Rats1  

UK PubMed Central (United Kingdom)

Reproductive aging in males is characterized by a diminution in sexual behavior beginning in middle age. We investigated the relationships among testosterone, androgen receptor (AR) and estrogen...Full Text Available

2010-07-01

171

Aging alters the expression of neurotransmission-regulating proteins in the hippocampal synaptoproteome  

UK PubMed Central (United Kingdom)

Decreased cognitive performance reduces independence and quality of life for aging individuals. Healthy brain aging does not involve significant neuronal loss, but little is known about the...Full Text Available

2010-06-01

172

Ageing in Drosophila: The role of the insulin/Igf and TOR signalling network  

UK PubMed Central (United Kingdom)

A remarkable discovery of recent years is that, despite the complexity of ageing, simple genetic interventions can increase lifespan and improve health during ageing in laboratory animals. The pathways...Full Text Available

2011-05-01

173

Advanced glycation end-products in senile diabetic and non-diabetic patients with cardiovascular complications  

UK PubMed Central (United Kingdom)

Advanced glycation end products (AGEs) have been reported to contribute to aging and cardiovascular complications. In the present study, the immunoreactivity of AGEs in human serum samples of healthy...Full Text Available

2008-12-01

174

AGEs Secreted by Bacteria Are Involved in the Inflammatory Response  

UK PubMed Central (United Kingdom)

Advanced Glycated End Products (AGEs) are formed by non-enzymatic protein glycation and are implicated in several physiological aspects including cell aging and diseases. Recent data indicate that bacteria...Full Text Available

175

Thermal stability of mixed-cation #alpha#-sialon ceramics  

International Nuclear Information System (INIS)

A series of #alpha#-sialon (#alpha#') compositions containing mixed stabilising cations were prepared, by introducing additional CaO to a basic Sm #alpha#-sialon compositions. The thermal stability of these Sm-Ca-containing #alpha#-sialon phases was investigated using XRD, SEM and EDXS techniques. It was found that the addition of calcium into the Sm #alpha#-sialon systems greatly improved the stability of the #alpha#-sialon phases. Calcium was found to be incorporated into the #alpha#-sialon structure, coexistent with the samarium, and partitioning of the calcium and samarium was observed between the #alpha#' phase and grain boundary phases. This indicates a technique which may be used to improve the thermal stability of the #alpha#' phase while maintaining good refractory phases at the sialon grain boundaries.

2003-01-02

176

Spermatozoa of Sharpsnout sea bream (Diplodus puntazzo) and European sea bass (Dicentrarchus labrax) express opioid receptors  

British Library Electronic Table of Contents (United Kingdom)

Endogenous opioid peptides (EOP) are molecules affecting many biological functions influencing productive and reproductive performance. They increase in stress conditions and interact with specific opioidergic receptors (OR): delta, kappa and mu. Several studies in other animal species suggest that they can also affect sperm cell motility. In fish the ionic external environment modulates the increase of intracellular calcium ion that is required to activate sperm motility after spawning. In mammals OR are functionally associated to calcium channels and in fishes calcium is highly required for fish sperm activation. In this study the presence of OR on spermatozoa of two Perciform fish, the sharpsnout seabream (Diplodus puntazzo, family Sparidae) and the European sea bass (Dicentrarchus labr...

2010-01-01

177

Separation of lithium and calcium isotopes during chemical isotopic exchange in extraction systems with phosphoryl-containing podands  

International Nuclear Information System (INIS)

A study was made on extraction of a series of lithium and calcium salts by monopodands L with common formula R-C_6H_4-O-(CH_2CH_2O)_n-C_6H_4-R, where R - CH_2P(O)Ph_2, n 1-3. Extraction-chromatographic separation of lithium and calcium isotopes in systems of metal aquacomplex-solvatocomplex with L in organic phase was conducted. It was established that separation coefficients of "6Li/"7Li isotopes ranged between 1.003 #+-#0.001 and 1.017 #+-#0.002 at the maximal separation degree equal to 1.60. Separation of "4"0Ca/"4"4Ca isotopes was not fixed. 12 refs., 4 figs., 1 tab.

178

Process for producing calcium sulfate dihydrate during desulfurization of stack gases from power station boilers. Verfahren zur Herstellung von Calciumsulfat-Dihydrat im Zuge der Entschwefelung von Rauchgasen aus Kraftwerkskesselfeuerungen  

Energy Technology Data Exchange (ETDEWEB)

This is a process for producing calcium sulfate dihydrate during desulfurization of stack gases from power station boilers, where the stack gases are introduced into a washing tower and are treated with a washing water suspension containing lime in the washing tower, where oxygen in the form of air or of air enriched in oxygen is also blown into the washing tower, and where the washing water suspension drawn off from the washing tower is fed back to the washing tower at a temperature of 45 to 50/sup 0/C in the circuit and at least part of the flow goes via a thickener and where calcium sulfate dihydrate slurry is drawn off from the thickener.

1986-06-12

179

Nanoscale calcium bismuth mixed oxide with enhanced photocatalytic performance under visible light  

British Library Electronic Table of Contents (United Kingdom)

The objective of materials research is the development of economical, safe and efficient synthesis routes that lead to the formation of a photocatalyst which is able to overcome performance problems related to particle size, crystallinity, or low surface area. Here, we report high-quality functional nanoparticles of calcium bismuth mixed oxide with 15nm nominal size corresponding to a specific surface area of 41m^2/g which were produced by single-step flame spray synthesis (FSS). The high temperature of the flame afforded creation of oxygen vacancies which were quantified by near edge X-ray absorption fine structure (NEXAFS) spectra. These two parameters, developed active surface area and created in the flame oxygen vacancies, allowed to enhance the photocatalytic activity of calcium bismu...

2010-01-01

180

Mineral carbonation accelerated by dicarboxylic acids as a disposal process of carbon dioxide  

British Library Electronic Table of Contents (United Kingdom)

Mineral carbonation is based on the reaction of carbon dioxide with metal-oxide bearing minerals, usually containing magnesium or calcium silicate, to form hardly soluble carbonates and other solid byproducts. The concept is based on acceleration of the naturally occurring rock weathering process. In the present work the calcium silicate is present in the mineral, wollastonite. To accelerate the process and make it potentially useful for practical applications, mineral carbonation is conducted here using an indirect two-step route in which the reactive component (Ca^2^+ ions in considered case) is first extracted from the mineral matrix and afterwards carbonated. Two solid byproducts are formed in this process: silica in the extraction step and calcium carbonate in the carbonation step. In...

2011-01-01

181

Luminescence properties of thallium crystal phosphors and their use in determining microgram quantities of thallium  

Energy Technology Data Exchange (ETDEWEB)

The preparation and luminescence properties of crystal phosphors based on alkali metal iodide and calcium oxide substrates were studied. The highest luminescence intensities were achieved with iodide substrates at 200/sup 0/ and with the calcium oxide substrate at 800/sup 0/. The calibration graphs were linear in the thallium concentration ranges 0.03-5.0 and 0.1-2.0 mu g using sodium and potassium oxides, respectively, and in the range 0.05-5 mu g using cesium iodide and calcium oxide. A method is proposed for the determination of down to 3 x 10/sup -4/% thallium in rocks, using a crystal phosphor with sodium iodide substrate.

1986-02-01

182

Depression of calcium pump activity in renal cortex of vitamin D-deficient rats with secondary hyperparathyroidism  

Energy Technology Data Exchange (ETDEWEB)

To examine the hormonal regulation of the ATP-dependent Ca{sup 2+} pump in the kidneys, the ATP-dependent Ca{sup 2+} uptake by the basolateral membrane vesicles in the renal cortex was measured using radioactive calcium ({sup 45}Ca{sup 2+}) in rats with vitamin D deficiency or rats undergoing thyroparathyroidectomy. The V{sub max} of the Ca{sup 2+} pump activity was increased not only by administering calcitriol, but also by normalizing the serum calcium level in vitamin D-deficient rats. PTH suppressed the Ca{sup 2+} pump activity in normocalcemic vitamin D-deficient rats. Thyroparathyroidectomy did not affect the Ca{sup 2+} pump activity in the kidneys of normal rats. It was concluded that the ATP-dependent Ca{sup 2+} pump activity was depressed by secondary hyperparathyroidism in vitamin D-deficient rats. (author).

1990-01-01

183

Depression of calcium pump activity in renal cortex of vitamin D-deficient rats with secondary hyperparathyroidism  

International Nuclear Information System (INIS)

To examine the hormonal regulation of the ATP-dependent Ca"2"+ pump in the kidneys, the ATP-dependent Ca"2"+ uptake by the basolateral membrane vesicles in the renal cortex was measured using radioactive calcium ("4"5Ca"2"+) in rats with vitamin D deficiency or rats undergoing thyroparathyroidectomy. The V_m_a_x of the Ca"2"+ pump activity was increased not only by administering calcitriol, but also by normalizing the serum calcium level in vitamin D-deficient rats. PTH suppressed the Ca"2"+ pump activity in normocalcemic vitamin D-deficient rats. Thyroparathyroidectomy did not affect the Ca"2"+ pump activity in the kidneys of normal rats. It was concluded that the ATP-dependent Ca"2"+ pump activity was depressed by secondary hyperparathyroidism in vitamin D-deficient rats. (author).

184

Chemistry of strontium  

International Nuclear Information System (INIS)

This paper describes stable strontium as composed of four stable isotopes ( Sr 88, Sr 87, Sr 86, and Sr 84), of which Sr 88 contributes more than 82% to its composition. Strontium exists in three crystalline, plymorphic forms; face-centered cubic alpha form, hexagonal beta form and body-centered cubic gamma form. Strontium occupies in many physicochemical aspects an intermediate position between calcium and barium, as does the solubility of strontium salts. As a result of its oxidation potential, strontium readily forms oxides, halides, and sulfide. The author proposes that the slight discrimination against strontium incorporation into bony tissues may be due to the difference in ionic potential (14%) between strontium and calcium. Ionic potential is an indicator of the strength of ionic bonds: strontium has a smaller ratio of ionic charge to ionic radius when compared with calcium.

185

Multiple stress aging of solid-dielectric extruded dry-cured insulation systems for power transmission cables  

Energy Technology Data Exchange (ETDEWEB)

A detailed examination of the aging processes that may take place in solid-dielectric extruded-type high voltage transmission cables under dry conditions is presented. Particular emphasis is placed on the aging process as affected by the separate and simultaneous action of four main aging factors, namely the electrical, mechanical and thermal stresses, and the physical and chemical environment. A number of pertinent aging models are considered and their validity and applicability to accelerated aging tests on solid-type transmission cables are discussed.

1994-01-01

186

Accelerated-aging tests for predicting radiation degradation of organic materials  

Energy Technology Data Exchange (ETDEWEB)

Long-term aging of organic materials in reactor containment buildings has become a major issue within the nuclear community. In this article, the status of radiation-aging qualification test requirements in several countries is reviewed, and problems with the current aging methodologies are described. These problems include dose-rate and synergistic effects and environmental synergisms, which have been found for many different polymeric materials. A number of approaches to improved accelerated-radiation-aging tests for prediction of long-term aging behavior are discussed together with their limitations.

1984-03-01

187

Accelerated-aging tests for predicting radiation degradation of organic materials  

International Nuclear Information System (INIS)

Long-term aging of organic materials in reactor containment buildings has become a major issue within the nuclear community. In this article, the status of radiation-aging qualification test requirements in several countries is reviewed, and problems with the current aging methodologies are described. These problems include dose-rate and synergistic effects and environmental synergisms, which have been found for many different polymeric materials. A number of approaches to improved accelerated-radiation-aging tests for prediction of long-term aging behavior are discussed together with their limitations.

1984-01-01

188

War in the Information Age: A Primer for Cyberspace ...  

Science.gov (United States)

... A Primer for Cyberspace ... 4. TITLE AND SUBTITLE War in the Information Age: A Primer for Cyberspace Operations in 21st Century Warfare 5a. ...

2011-05-15

189

Tragedy and delight: the ethics of decelerated ageing  

UK PubMed Central (United Kingdom)

Biogerontology is sometimes viewed as similar to other forms of biomedical research in that it seeks to understand and treat a pathological process. Yet the prospect of treating ageing is extraordinary...Full Text Available

2011-01-12

190

The sites and topology of mitochondrial superoxide production  

UK PubMed Central (United Kingdom)

Mitochondrial superoxide production is an important source of reactive oxygen species in cells, and may cause or contribute to ageing and the diseases of ageing. Seven major sites of superoxide...Full Text Available

2010-08-01

191

Reversing B cell aging  

UK PubMed Central (United Kingdom)

Age-related alterations in the cellular composition of the B lineage are a major cause of the poor antibody response to vaccination and to infectious agents among the elderly population. The mechanisms...Full Text Available

192

Polyphenols and Aging  

UK PubMed Central (United Kingdom)

Age-associated changes within an individual are inherently complex and occur at multiple levels of organismal function. The overall decline in function of various tissues is known to play a...Full Text Available

2010-02-01

193

Oxidative Damage and the Prevention of Age-Related Cataracts  

UK PubMed Central (United Kingdom)

PurposeCataracts are often considered to be an unavoidable consequence of aging. Oxidative damage is a major cause or consequence of cortical and nuclear cataracts, the most common...Full Text Available

2010-09-01

194

Mitochondrial ROS production correlates with, but does not directly regulate lifespan in drosophila  

UK PubMed Central (United Kingdom)

The Mitochondrial Free Radical Theory of Aging (MFRTA) is currently one of the most widely accepted theories used to explain aging....Full Text Available

195

Mice as a Mammalian Model for Research on the Genetics of Aging  

UK PubMed Central (United Kingdom)

Mice are an ideal mammalian model for studying the genetics of aging: considerable resources are available, the generation time is short, and the environment can be easily controlled, an important...Full Text Available

2011-02-08

196

DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY  

Science.gov (United States)

... Title : DUCTILITY RATIO OF AGED BETA TITANIUM ALLOY. Corporate Author : NEW YORK UNIV NY SCHOOL OF ENGINEERING AND SCIENCE. ...

1962-01-02

197

Considerations on Temperature, Longevity and Aging  

UK PubMed Central (United Kingdom)

A modest reduction in body temperature prolongs longevity and possibly retards aging in both poikilotherm and homeotherm animals. Some of the possible mechanisms mediating these effects are...Full Text Available

2008-06-01

198

Computational biology for ageing  

UK PubMed Central (United Kingdom)

High-throughput genomic and proteomic technologies have generated a wealth of publicly available data on ageing. Easy access to these data, and their computational analysis, is of great importance in...Full Text Available

2011-01-12

199

Can microRNAs act as biomarkers of aging?  

UK PubMed Central (United Kingdom)

Aging can be defined as a progressive decline in physiological efficiency regulated by an extremely complex multifactorial process. The genetic makeup of an individual appears to dictate this rate...Full Text Available

200

Apoptosis at Inflection Point in Liquid Culture of Budding Yeasts  

UK PubMed Central (United Kingdom)

Budding yeasts are highly suitable for aging studies, because the number of bud scars (stage) proportionally correlates with age. Its maximum stages are known ...Full Text Available

201

Age and the Thyrotropin Response to Hypothyroxinemia  

UK PubMed Central (United Kingdom)

Context: Some studies suggest altered pituitary functioning and TSH production with aging.Objective: Our objective was to test the hypothesis that less TSH production...Full Text Available

2010-08-01

202

Zinc release from thapsigargin/IP3-sensitive stores in cultured cortical neurons  

UK PubMed Central (United Kingdom)

BackgroundChanges in ionic concentration have a fundamental effect on numerous physiological processes. For example, IP3-gated thapsigargin sensitive intracellular calcium...Full Text Available

203

Vectors containing a prokaryotic dihydrofolate reductase gene transform Drosophila cells to methotrexate-resistance.  

UK PubMed Central (United Kingdom)

Transformed Drosophila Kc cell lines, resistant to methotrexate, an inhibitor of de novo purine and pyrimidine synthesis, have been obtained by calcium phosphate transfection of plasmids containing...Full Text Available

1983-01-01

204

The opening of the two pores of the Hv1 voltage-gated proton channel is tuned by cooperativity  

UK PubMed Central (United Kingdom)

SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available

2010-01-01

205

The nucleation kinetics of calcium sulfate dihydrate in NaCl solutions up to 6 m and 90 C  

Energy Technology Data Exchange (ETDEWEB)

The crystallization of calcium sulfate from aqueous solutions with NaCl is both geological and industrial interest because NaCl is the dominant solute in natural brines and many industrial fluids. Induction periods for the nucleation of calcium sulfate dihydrate were experimentally determined as a function of supersaturation in NaCl solutions from 0 to 6 m at 25 C and in 3.0-m NaCl solutions at temperatures from 25 to 90 C. Using classic nucleation theory, the interfacial tension between gypsum and 3.0-m NaCl solution was estimated to be about 39 mJ/m[sup 2] at 25 C and increases with increasing temperature (to 63 mJ/m[sup 2] at 90 C). It was observed that the induction period decreases with increasing NaCl concentrations up to 3 m and then starts to increase slightly at a given temperature and saturation state. The electrolyte effect on nucleation was proportional to the enhanced solubility of calcium sulfate dihydrate in ...

1994-02-01

206

The L-type calcium channel inhibitor diltiazem prevents cardiomyopathy in a mouse model  

UK PubMed Central (United Kingdom)

Dominant mutations in sarcomere protein genes cause hypertrophic cardiomyopathy, an inherited human disorder with increased ventricular wall thickness, myocyte hypertrophy, and disarray. To understand...Full Text Available

2002-04-15

207

Studies on Inhibition of Intestinal Absorption of Radioactive Strontium  

UK PubMed Central (United Kingdom)

A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, permitting the calcium to be available to the body. Studies were carried...Full Text Available

1964-08-08

208

Strength and fluoride release characteristics of a calcium fluoride based dental nanocomposite  

UK PubMed Central (United Kingdom)

Secondary caries and restoration fracture remain the two most common problems in restorative dentistry. Release of fluoride ions (F) could be a substantial benefit because F could enrich neighboring...Full Text Available

2008-11-01

209

Severe Hypocalcemia due to Vitamin D Deficiency after Extended Roux-en-Y Gastric Bypass  

UK PubMed Central (United Kingdom)

Vitamin D deficiency is a well-known comorbidity of obesity that can be exacerbated after bariatric surgery and can predispose the patient for hypocalcemia. Vitamin D and calcium doses to prevent and...Full Text Available

2011-01-01

210

Role of Calcium in Serine Transport into Tobacco Cells  

UK PubMed Central (United Kingdom)

The transport of serine into tobacco (Nicotiana tabacum L. var. Xanthi) cells grown in liquid medium was studied. Serine transport was maximal below pH 4.0. A time-dependent stimulation...Full Text Available

1978-12-01

211

Resistance of Bacillus subtilis var. niger Spores Occluded in Water-insoluble Crystals to Three Sterilization Agents  

UK PubMed Central (United Kingdom)

The resistance to destruction of spores of Bacillus subtilis var. niger occluded in crystals of calcium carbonate and exposed to ethylene oxide and moist and dry heat...Full Text Available

1967-07-01

212

Regulation of Vacuolar H+-Pyrophosphatase by Free Calcium 1  

UK PubMed Central (United Kingdom)

The H+-translocating inorganic pyrophosphatase (H+-PPase) associated with vesicles of the vacuolar membrane (tonoplast) isolated from beet (Beta vulgaris L.) is...Full Text Available

1992-12-01

213

Regulation of Calcium Influx in Chara1  

UK PubMed Central (United Kingdom)

Measurements were made of 45Ca influx into isolated internodal cells of Chara corallina and also into internodal cells of intact plants. 45Ca influx was closely...Full Text Available

1992-10-01

214

Rapid Action of Estrogens on Intracellular Calcium Oscillations in Primate Luteinizing Hormone-Releasing Hormone-1 Neurons  

UK PubMed Central (United Kingdom)

Feedback controls of estrogen in LHRH-1 neurons play a pivotal role in reproductive function. However, the mechanism of estrogen action in LHRH-1 neurons is still unclear. In the present study, the...Full Text Available

2008-03-01

215

Radionuclide X-ray fluorescence analysis of waste water from the production of citric acid  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid.

1982-02-18

216

Radionuclide X-ray fluorescence analysis of waste water from the production of citric acid  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis was used for the determination of iron, calcium, potassium, copper, manganese and zinc in waste water from the production process of citric acid. (author).

1982-02-01

217

Propagation of an alkaline wave with a short contact time through an argilite sample from the Meuse-Haute Marne underground laboratory; Propagation d'une onde alcaline a temps de contact court a travers un echantillon d'argilite de l'est  

Energy Technology Data Exchange (ETDEWEB)

In the framework of the feasibility study of radioactive waste disposal in deep geologic formations, a clay formation (named 'argilite de l'Est') has been selected in the Meuse-Haute Marne region (France) for the construction of an underground laboratory. The percolation of alkaline solutions through the argilite has been studied using column experiments with short residence times (30 min). These experiments simulate the leaching of a cement which could be used in the building materials of the laboratory. The alkaline solutions used are mono-cationic solutions of calcium, sodium and strontium. The behaviour of calcium is differentiated from the other cations. For all alkaline solutions (NaOH, Ca(OH){sub 2} or Sr(OH){sub 2}) chemical reactions consuming both hydroxide ions and their associated cations have been evidenced. These reactions are heterogenous reactions of surface adsorption by site ionization. The ...

2001-07-01

218

Process for the removal of sulfur oxides from exhaust gases using slurry of red mud containing calcium ion  

Energy Technology Data Exchange (ETDEWEB)

A process is given for the removal of sulfur oxides from exhaust gases by absorbing with a slurry of red mud containing calcium ion which comprises the steps of: (1) contacting an exhaust gas containing sulfur oxides of not higher than about 100/sup 0/ C with a slurry of red mud containing calcium ion led from the next step (2) to take up sulfur oxides in the gas until ph of the slurry becomes in the range of 4.3 to less than 6 while maintaining the molar fraction of SO/sub 4/-- to total SO/sub 2/ in the slurry within the said pH range at 0.05 to 0.7; and then, (2) contacting the treated gas with a fresh slurry of red mud containing calcium ion to further take up sulfur oxides in the gas while maintaining the concentration of NaHSO/sub 3/ in the slurry at not more than about 8 g/l.

1980-09-16

219

Physiological calcium concentrations regulate calmodulin binding and catalysis of adenylyl cyclase exotoxins  

UK PubMed Central (United Kingdom)

Edema factor (EF) and CyaA are calmodulin (CaM)-activated adenylyl cyclase exotoxins involved in the pathogenesis of anthrax and whooping cough, respectively. Using spectroscopic, enzyme kinetic and...Full Text Available

2002-12-16

220

Neurobehavioral effects of power-frequency electromagnetic fields.  

UK PubMed Central (United Kingdom)

Some laboratory experiments have suggested that power-frequency electric and magnetic fields (EMF) may be capable of influencing calcium efflux from cell membranes, pineal function, and circadian rhythms....Full Text Available

1993-12-01

221

Intra- and extracellular calcium modulates stereocilia stiffness on chick cochlear hair cells.  

UK PubMed Central (United Kingdom)

Segments of the chick basilar papilla were isolated and maintained in culture medium. The sensory hair bundle of individual hair cells was observed with light microscopy and stimulated with a water...Full Text Available

1994-02-01

222

Imaging of calcium transients in skeletal muscle fibers.  

UK PubMed Central (United Kingdom)

Epifluorescence images of Ca2+ transients elicited by electrical stimulation of single skeletal muscle fibers were studied with fast imaging techniques that take advantage of the large fluorescence...Full Text Available

1991-01-01

223

Hysteretic Behavior of Proprotein Convertase 1/3 (PC1/3)  

UK PubMed Central (United Kingdom)

The proprotein convertases (PCs) are calcium-dependent proteases responsible for processing precursor proteins into their active forms in eukariotes. The PC1/3 is a pivotal enzyme of this family that...Full Text Available

224

Hydrogenolysis reaction of deashed coal loaded K and Ca. K to Ca wo tanjishita dakkai sekitan no suisoka bunkai tokusei  

Energy Technology Data Exchange (ETDEWEB)

Taiheiyo coal deashed using acid treatment and loaded with potassium or calcium was hydro-cracked under gaseous phase to discuss effects of these metals on liquefaction reaction. In addition, the loaded coal was added with red mud catalyst to examine effects of the addition. The loaded potassium has a softening power, and particularly the potassium adsorbed into surface and micropores in the coal decomposes selectively HI-BS and BI-PS and generates gas and HS. On the other hand, potassium deposited on coal surface promotes direct gas production from the coal. Irrespective of its loading modes, calcium has a catalytic nature to produce HI-BS selectively. Calcium also acts to impede decomposition of HI-BS into HS. Adding red mud catalyst to potassium loaded coal increases the inversion rate and the liquefaction yield, and most of the increase is accounted for by HI -BS, and BI-PS. When red mud catalyst is added to ...

1992-11-05

225

Gynura procumbens Merr. decreases blood pressure in rats by vasodilatation via inhibition of calcium channels  

UK PubMed Central (United Kingdom)

INTRODUCTION:Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensin‐converting enzyme. However, other mechanisms that...Full Text Available

2011-01-01

226

Effects of Prolonged High Phosphorus Diet on Phosphorus and Calcium Balance in Rats  

UK PubMed Central (United Kingdom)

The amount of phosphorus contained in food as food additives is currently increasing and a high intake of phosphorus can cause various diseases. To determine the effects of a prolonged high phosphorus...Full Text Available

2007-05-01

227

Effect of Anionic Salt and Highly Fermentable Carbohydrate Supplementations on Urine pH and on Experimentally Induced Hypocalcaemia in Cows  

UK PubMed Central (United Kingdom)

The objective of this experiment was to determine the effect of dietary grain on calcium homeostasis. Six rumen-fistulated dairy cows with 3 or more previous lactations and no history of parturient...Full Text Available

2004-01-01

228

Disulfide Bonds and the Quaternary Structure of Factor VIII/von Willebrand Factor  

UK PubMed Central (United Kingdom)

Human Factor VIII/von Willebrand factor, purified by calcium citrate-cellulose chromatography and 4% agarose gel filtration was subjected to sodium dodecyl sulfate gel electrophoresis on gels containing...Full Text Available

1978-09-01

229

Dietary Ammonium Chloride for the Acidification of Mouse Urine  

UK PubMed Central (United Kingdom)

A novel therapeutic compound was found to induce bladder tumors in male rats. Given the location of the tumors and the increased amounts of calcium- and magnesium-containing solids found in the urine...Full Text Available

2009-03-01

230

Cytoplasmic Calcium Increases in Response to Changes in the Gravity Vector in Hypocotyls and Petioles of Arabidopsis Seedlings1  

UK PubMed Central (United Kingdom)

Plants respond to a large variety of environmental signals, including changes in the gravity vector (gravistimulation). In Arabidopsis (Arabidopsis thaliana) seedlings, gravistimulation...Full Text Available

2008-02-01

231

Citrat og nyresten  

DEFF Research Database (Denmark)

Citrate is an important naturally occurring inhibitor of calcium stone formation in urine. Urinary citrate excretion was examined in 43 consecutive patients with recurrent idiopathic calcium nephrolithiasis and in 50 normal controls by a specific enzymatic technique. Hypocitraturia (<1.6 mmol/24h) was found in 14 (33%) stone formers compared to 6 (12%) normal controls (p = 0.03). Citrate excretion expressed as citrate-creatinine ratio in 24 hour urine samples was significantly lower in the stone formers than in the healthy controls (p = 0.03), and significantly lower in healthy men, compared to healthy females (p = 0.006). There was a great variability in urinary citrate levels in both groups, and a considerable overlap in the urinary citrate excretion between normal subjects and stone formers. Factors other than urinary citrate excretion must therefore be of importance in the pathophysiology of calcium stone formation. ...

1993-01-01

232

Chemical neutralization to control denting in nuclear steam generators  

International Nuclear Information System (INIS)

Laboratory testing at Combustion Engineering has indicated promise in controlling simulated steam generator tube denting through chemical neutralization. Testing was limited to on-line treatment, and two neutralizers have been evaluated: calcium hydroxide and boric acid. On-line treatment with calcium hydroxide successfully halted active denting whenever the bulk calcium concentration (in ppm) equaled or exceeded the bulk chloride concentration (in ppm). Calcium hydroxide also was effective as an alternative to ammonia as a pH controlling agent in two tests conducted without ingress of chloride. On-line treatment with boric acid consisted of a four-day soak at simulated low (approximately 30 percent) power with 50 ppm B followed by one month full-power operation with 10 ppm B. This treatment also halted denting. Nondestructive and destructive examination of test boilers gave no indication of adverse ...

233

Case series of maxillary sinus augmentation with biphasic calcium phosphate: a clinical and radiographic study  

UK PubMed Central (United Kingdom)

PurposeThe aim of this study was to evaluate 3.5 years-cumulative survival rate of implants placed on augmented sinus using Osteon, a bone graft material, and to assess the height...Full Text Available

2011-04-01

234

Calcium/Calmodulin-Dependent Protein Kinase II Mediates Hippocampal Glutamatergic Plasticity During Benzodiazepine Withdrawal  

UK PubMed Central (United Kingdom)

Benzodiazepine withdrawal anxiety is associated with potentiation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPAR) currents in hippocampal CA1 pyramidal...Full Text Available

2010-08-01

235

Calcium gradients and buffers in bovine chromaffin cells.  

UK PubMed Central (United Kingdom)

1. Digital imaging and photometry were used in conjunction with the fluorescent Ca2+ indicator, Fura-2, to examine intracellular Ca2+ signals produced by depolarization of single adrenal chromaffin...Full Text Available

1992-05-01

236

Calcium Effects on Stomatal Movement in Commelina communis L. 1  

UK PubMed Central (United Kingdom)

Stomatal movements depend on both ion influx and efflux; attainment of steady state apertures reflects modulation of either or both processes. The role of Ca2+ in those two processes was...Full Text Available

1988-07-01

237

Cadherin Mechanics and Complexation: The Importance of Calcium Binding  

UK PubMed Central (United Kingdom)

E-cadherins belong to a family of membrane-bound, cellular adhesion proteins. Their adhesive properties mainly involve the two N-terminal extracellular domains (EC1 and EC2). The junctions between these...Full Text Available

2005-12-01

238

Amyloid Oligomer Neurotoxicity, Calcium Dysregulation, and Lipid Rafts  

UK PubMed Central (United Kingdom)

Amyloid proteins constitute a chemically heterogeneous group of proteins, which share some biophysical and biological characteristics, the principal of which are the high propensity to acquire an incorrect...Full Text Available

239

Acetylsalicylic acid as soluble tablets  

International Science & Technology Center (ISTC)

Realization of Pharmacological Tests, Development of the Specifications and Technical Documentation and Registration in the Russian Federation of Medical Products as Soluble Tablets of Acetylsalicylic Acid/Calcium Carbonate in Two Dosages Intended for use as Medical Products Smoothing, Febrifugal and Antiaggregation Action and Development of Technology of Tableting the Above-Stated Preparations

240

A new method to measure necrotic core and calcium content in coronary plaques using intravascular ultrasound radiofrequency-based analysis  

UK PubMed Central (United Kingdom)

Although previous intravascular ultrasound (IVUS) radiofrequency-based analysis data showed acceptable reproducibility for plaque composition, measurements are not easily obtained, particularly that...Full Text Available

2010-04-01

241

A mathematical/physiological model of parathyroid hormone secretion in response to blood-ionized calcium lowering in vivo.  

DEFF Research Database (Denmark)

The aim of the present study was to test a mathematical model of the biochemical processes in the parathyroid glands responsible for the secretion of parathyroid hormone resulting from extracellular calcium reduction. A double exponential curve described the parathyroid hormone secretion induced by rapid lowering of blood-ionized calcium in humans with normal as well as abnormal parathyroid tissue. Our data show that it was possible to establish a simple mathematical model of the parathyroid hormone response to blood-ionized calcium lowering, sufficient to fit experimental data obtained from patients with abnormal and normal parathyroid tissue. The fitted parameters showed no significant differences between patients with insulin-dependent diabetes mellitus and controls. In primary hyperparathyroidism, the parathyroid hormone production and steady-state transport across the cell membrane were increased, probably due to the ...

1997-01-01

242

A Kinetic Model of Dopamine- and Calcium-Dependent Striatal Synaptic Plasticity  

UK PubMed Central (United Kingdom)

Corticostriatal synapse plasticity of medium spiny neurons is regulated by glutamate input from the cortex and dopamine input from the substantia nigra. While cortical stimulation alone results in long-term...Full Text Available

2010-02-01

243

* NASA TECHNICAL TRANSLATION NASA TT F-11435 INFLUENCE OF ...  

Science.gov (United States)

isotherme, dans un courant d'azote ou sous vide entretenu. I t. Comptes Rendus Scientific Academy, Paris, Vol. 265 pyrolyse du carbonate de calcium, ...

244

Indium-cadmium-oxide films having exceptional electrical conductivity and optical transparency: Clues for optimizing transparent conductors  

UK PubMed Central (United Kingdom)

Materials with high electrical conductivity and optical transparency are needed for future flat panel display, solar energy, and other opto-electronic technologies. InxCd1-xO...Full Text Available

2001-06-19

245

Identification of Thlaspi caerulescens Genes That May Be Involved in Heavy Metal Hyperaccumulation and Tolerance. Characterization of a Novel Heavy Metal Transporting ATPase1  

UK PubMed Central (United Kingdom)

Thlaspi caerulescens is a heavy metal hyperaccumulator plant species that is able to accumulate extremely high levels of zinc (Zn) and cadmium (Cd) in its shoots (30,000 μg...Full Text Available

2004-11-01

246

Heavy Metals in selected Edible Vegetables and their daily intake in Sanandaj, Iran  

Energy Technology Data Exchange (ETDEWEB)

The levels of four different heavy metals [cadmium (Cd), lead (Pb), chromium (Cr) and copper (Cu)] were determined in various vegetables [leek (Allium ampeloprasum), sweet basil (Ocimum basilicum), parsley (Petroselium cripsum), gardem cress (lepidium sativum) and tarragon (Artemisia dracuncullus)] cultivated around the Sanandaj city. (Author)

2009-07-01

247

Heavy Metals in selected Edible Vegetables and their daily intake in Sanandaj, Iran  

International Nuclear Information System (INIS)

The levels of four different heavy metals [cadmium (Cd), lead (Pb), chromium (Cr) and copper (Cu)] were determined in various vegetables [leek (Allium ampeloprasum), sweet basil (Ocimum basilicum), parsley (Petroselium cripsum), gardem cress (lepidium sativum) and tarragon (Artemisia dracuncullus)] cultivated around the Sanandaj city. (Author)

248

Final Report: Planetary Instrument Definition and Design Program (PIDDP) Support Project  

Energy Technology Data Exchange (ETDEWEB)

The results of Sandia National Laboratories' participation in the NASA Planetary Definition and Design Program are summarized. Areas reported include the characterization of large area cadmium zinc telluride spectrometers and the application of simulation techniques to the prediction of device performance. Also investigated was the response of mercuric iodide devices in the region from 1 to 100 KeV. A literature study to determine the status or radiation damage measurements in room temperature semiconductor devices is also reported.

1999-03-01

249

Yttrium Calcium Oxyborate for high average power frequency doubling and OPCPA  

Science.gov (United States)

Significant progress has been achieved recently in the growth of Yttrium Calcium Oxyborate (YCOB) crystals. Boules have been grown capable of producing large aperture nonlinear crystal plates suitable for high average power frequency conversion or optical parametric chirped pulse amplification (OPCPA). With a large aperture (5.5 cm x 8.5 cm) YCOB crystal we have demonstrated a record 227 W of 523.5nm light (22.7 J/pulse, 10 Hz, 14 ns). We have also demonstrated the applicability of YCOB for 1053 nm OPCPA.

2006-06-20

250

The early days of parathyroid surgery.  

Science.gov (United States)

The parathyroid endocrine glands, usually four in number and about the size of a split pea, lie on either side of the posterior aspect of the thyroid gland. Occasionally one or more of these structures are found in an aberrant position in the neck or even in the superior mediastinum. The parathyroid secretion, parathormone, regulates the level of serum calcium within sharply defined limits. Lack of parathormone, with lowering of the serum calcium, results in hyper-irritability of skeletal muscle, the clinical condition known as tetany. This is encountered following inadvertent removal or bruising of the parathyroid glands at thyroidectomy. PMID:21488463

2011-03-01

251

Stabilisation of #alpha#-Sialons using multiple additives  

International Nuclear Information System (INIS)

Multi-cation #alpha#-Sialon ceramics were prepared using mixtures of samarium with calcium, magnesium, yttrium and ytterbium, and compared with a pure Sm-Sialon of equivalent total stabilising cation composition. A ratio of 80eq% samarium to 20eq% of the second stabilising additive was used. Samples were fired at 1820 deg C and subsequently heat treated at 1450 deg C. XRD phase analysis showed that all additives resulted in greater #alpha#-Sialon stability, and that calcium was the most effective additive for the stabilisation of the #alpha#-Sialon phase. Copyright (1998) Australasian Ceramic Society

1998-09-28

252

Physical aspects of FGD by-products  

Energy Technology Data Exchange (ETDEWEB)

Air pollution constraints continue to intensify, resulting in solid waste volume increases. An example of this is coal burning power plant flue gas desulfurization by scrubbing. The aqueous suspensions of calcium sulfate hemihydrate or calcium sulfate dihydrate will exceed 200 million tons annually by the year 2000. Disposal of these wastes can have massive environmental effects, due to physical instability and leaching to groundwater. One alternate disposal technique is sulfopozzolanic fixation, converting the FGD waste by addition of fine coal ash and an alkaline earth additive, into a monolithic mass. 6 refs., 17 figs., 3 tabs.

1992-01-01

253

New coumarin-based sensor molecule for magnesium and calcium ions  

British Library Electronic Table of Contents (United Kingdom)

A new coumarin-based sensor molecule (L1) has been synthesized and this was found to bind calcium and magnesium ions more effectively as compared to other alkali/alkaline earth/lanthanide and certain transition metal ions. A significant enhancement in fluorescence intensity was observed on binding to Ca2+ and Mg2+ ions; while a minor quenching was observed for weakly bound Hg2+, Ni2+, Fe3+, and Co2+ ions. PET process, coupled with the ICT process, is proposed to explain the observed spectral response.

2009-01-01

254

Method of producing calcium sulfate semihydrate in conjunction with the desulfurization of flue gases  

Energy Technology Data Exchange (ETDEWEB)

Calcium sulfate dihydrate in large crystal form is produced by maintaining the circulation of the lime containing scrubbing solution in the desulfurization scrubbing of flue gases from a power plant boiler so that it has a residence time of 5 to 25 hours, preferably 15 hours. The crystals are moved by passing a portion of the recirculation through a thinner in which a sludge containing crystals with a mean particle size of which 90% is in excess of 100 microns is removed. This product can be dewatered and treated with sulfuric acid and steam to convert it to the alpha semihydrate and is free from sulfite.

1985-03-05

255

Influence of microalloying on the corrosion resistance of steel in saturated calcium hydroxide  

International Nuclear Information System (INIS)

The influence of microalloying vanadium or titanium on improving the corrosion resistance of mild steel in saturated calcium hydroxide solution was investigated. Potential-time, potentiodynamic polarization, and impedance measurement techniques were employed. The corrosion products have been examined by infrared and X-ray diffraction analysis and by scanning electron microscopy. It has been shown that the grain refining, due to microalloying, plays an important role in enhancing the corrosion resistance of steel. Scales of calcite and iron oxides on top of a protective oxide are formed on the investigated steels.

256

Heat storage composition  

Energy Technology Data Exchange (ETDEWEB)

A heat storage compostion comprises sodium sulfate decahydrate as main component, a supercooling inhibitor, and a solid-liquid separation inhibitor. The composition is characterized in that hydraulic calcium sulfate and/or calcium sulfate dihydrate is contained as the solid-liquid separation inhibitor in an amount of 2-15 wt% base on the whole weight of the composition, whereby the solid-liquid separation, i.e. the sedimentation of the anhydrous sodium sulfate during the phase transition, is effectively prevented and the long-term stability is improved. The long-term stabilty of the composition can be more improved by addition of a silcia series of thickener.

1987-05-05

257

Exact solution to NO/sub 2/ absorption  

Energy Technology Data Exchange (ETDEWEB)

This paper describes an exact solution to the problem of absorbing nitrogen dioxide into aqueous solution, in which case the nitrogen dioxide concentration is allowed to vary over a wide range. The authors have worked on the rate of calcium sulfate dihydrate scale formation on the reverse osmosis membrane and find this phenomena can be treated by the crystallization theory. The authors performed long-term experiments using calcium sulfate dihydrate solution with addition of sodium hexametaphosphate (SHMP) and commercially available organophosphates and investigated the mechanism of the inhibitor's action quantitatively.

1984-04-01

262

Postweld aging of a metastable beta-titanium alloy  

International Nuclear Information System (INIS)

(Nov 1973). United States Greenfield, MA Pierce, CM Chicago, IL.

263

Monovision  

Medline Plus

... Precautions Comprehensive Eye and Vision Examination Nutrition Lutein Antioxidants & Age-Related Eye Disease Lutein and Zeaxanthin - Eye- ...

267

Foreign Affair's: Fool's Gold  

Wastenet

aged gracefully: premature and accelerated corro - sion, erosion, and stress are raising maintenance costs.Last

268

Rb-Sr ages and palaeomagnetic data for some Angolan alkaline intrusives  

International Nuclear Information System (INIS)

New Rb-Sr age measurements are reported for a number of intrusives from Angola. Data for the Njoio and Tchivira nepheline syenite bodies yield mineral isochrons indicating ages of 104,3+-0,8 Ma and 130,8+-1,4 Ma respectively. Palaeomagnetic studies on the same occurrences gave marginal and scattered results respectively. Micas from the Camafuca crater-facies kimberlite yielded and apparent age of 1 822+-151 Ma, a result that is far in excess of the Tertiary (or younger) age inferred for this pipe. Similarly conflicting data were obtained for the Nova Lisboa kimberlite. It is likely that older crustal micas incorporated in the kimberlite breccias are responsible for the anomalous ages reported on the kimberlites. Satisfactory palaeomagnetic data are reported for the Zenza and Bailundu occurrences, not dated by the Rb-Sr method. A convenient K-Ar age of 80+-0,8 Ma ...

269

Precipitation behavior and tensile property of the stress-aged Ti-10Mo-8V-1Fe-3.5Al alloy  

British Library Electronic Table of Contents (United Kingdom)

A kind of metastable beta titanium alloy, i.e. Ti-10Mo-8V-1Fe-3.5Al, was aged under elastic compressive stress. Transmission electron microscopy (TEM) investigations revealed that, in the stress-aged samples, precipitated alpha plates were parallel to each other. However, in the conventionally aged samples, alpha plates intersected each other. In other words, variant of alpha plate was selected in the stress-aged samples. Tensile tests showed that, at equivalent tensile strength, the stress-aged samples exhibited higher ductility, compared to the conventionally aged ones.

2011-01-01

270

Effect of mean stress (stress ratio) and aging on fatigue-crack growth in a metastable beta titanium alloy, Ti-10V-2Fe-3Al  

International Nuclear Information System (INIS)

The effect of mean stress, or the stress ratio (R), on the fatigue-crack growth (FCG) behavior of #alpha#-aged and #omega#-aged microstructures of the beta titanium alloy Ti-10V-2Fe-3Al was investigated. While the mean stress had a negligible effect on the FCG behavior of the #alpha#-aged microstructure, a strong effect was observed in the #omega#-aged microstructure. In particular, the values of the threshold stress-intensity range (#DELTA#K_t_h) exhibited a strong dependence on R in the #omega#-aged microstructure, while this dependence was weak in the #alpha#-aged microstructure. These effects seem to arise primarily from fracture-surface roughness-induced crack closure. The crack closure levels for the #alpha#-aged microstructure were found to be very low compared to those for the #omega#-aged microstructure. ...

2000-03-01

271

Safe ageing management of nuclear power plants: An European synthesis  

International Nuclear Information System (INIS)

Ageing of nuclear power plants means evolution of material or equipment properties on one side, and evolution of personnel skill and procedure adequacy on the other side, both of which, after a certain time, may not be compatible with the required safety provisions, or with an economic operation of the plant. Repair or replacement of components, as well as change in service conditions for a better compatibility with component reduced capabilities can be used to mitigate ageing effects. The paper summarises the results of a study conducted in this field with the support of the European Commission. It presents: the synthesis of the work done under international auspices, and in the European context; the comparison of ageing management approaches used in several European countries with international recommendations; the summary of the various potential phenomena and their governing parameters, the methods of in-service ...

2002-11-04

272

Simultaneous plasma nitriding and ageing treatments of precipitation hardenable plastic mould steel  

Energy Technology Data Exchange (ETDEWEB)

Simultaneous nitriding and ageing heat treatments of precipitation hardenable tool steel was carried out inside a DC-pulsed plasma nitriding reactor. A single heat treatment cycle was done, as the plasma nitriding and age hardening processes occur approximately at the same ranges of temperatures and times. Specimens of Cr-Ni-Mo-Al age hardenable steel, in the solubilized and solubilized and aged conditions, were tested. Plasma nitriding and ageing, carried out at 500 deg. C for times ranging between 2 and 8 h, increased the surface hardness up to 1000 HV, producing case depths between 100 and 200 {mu}m. The core hardness of solubilized samples increased from 30 to 39 Rockwell C after the plasma nitriding treatment proving the possibility of nitriding and ageing at the same treatment cycle. The pre-aged samples did not show any overageing ...

2007-07-01

273

Simultaneous plasma nitriding and ageing treatments of precipitation hardenable plastic mould steel  

International Nuclear Information System (INIS)

Simultaneous nitriding and ageing heat treatments of precipitation hardenable tool steel was carried out inside a DC-pulsed plasma nitriding reactor. A single heat treatment cycle was done, as the plasma nitriding and age hardening processes occur approximately at the same ranges of temperatures and times. Specimens of Cr-Ni-Mo-Al age hardenable steel, in the solubilized and solubilized and aged conditions, were tested. Plasma nitriding and ageing, carried out at 500 deg. C for times ranging between 2 and 8 h, increased the surface hardness up to 1000 HV, producing case depths between 100 and 200 #mu#m. The core hardness of solubilized samples increased from 30 to 39 Rockwell C after the plasma nitriding treatment proving the possibility of nitriding and ageing at the same treatment cycle. The pre-aged samples did not show any overageing ...

274

Ageing assessments with application of PSA Models  

International Nuclear Information System (INIS)

One of the main applications of PSA studies is related to identification of the major key issues related to plant safety. In standard PSA one assumes a constant value for component failure rates by considering that the component doesn't experience any degradation that could affect its performance. Used in this manner, standard PSA tools do not adequately address important ageing issues, and this fact could have a significant impact on the conclusions drawn from PSA studies and applications, in conditions of operation of ageing plants. To obtain realistic results, it is necessary to consider in the PSA model the ageing effects, and to do that it is necessary to take into consideration the change in component failure rate as a function of component age. In case of ageing phenomena, this dependence causes the failure rate of a component (or a set of components) to increase in time as ...

2009-10-12

275

Optimizing the specific surface area of fly ash-based sorbents for flue gas desulfurization.  

Science.gov (United States)

High performance sorbents for flue gas desulfurization can be synthesized by hydration of coal fly ash, calcium sulfate, and calcium oxide. In general, higher desulfurization activity correlates with higher sorbent surface area. Consequently, a major aim in sorbent synthesis is to maximize the sorbent surface area by optimizing the hydration conditions. This work presents an integrated modeling and optimization approach to sorbent synthesis based on statistical experimental design and two artificial intelligence techniques: neural network and genetic algorithm. In the first step of the approach, the main and interactive effects of three hydration variables on sorbent surface area were evaluated using a full factorial design. The hydration variables of interest to this study were hydration time, amount of coal fly ash, and amount of calcium sulfate and the levels investigated were 4-32 h, 5-15 g, and 0-12 g, respectively. In ...

2005-07-05

276

Contribution of calcium ions and hydrogen ions to the signal transduction chain in phytochrome-mediated spore germination. [Onoclea sensibilis L  

Energy Technology Data Exchange (ETDEWEB)

Red light stimulates germination in the spores of Onoclea sensibilis L. Phytochrome is confirmed to be the photoreceptor pigment in the germination response by demonstrating red-far-red photoreversibility. External Ca/sup 2 +/ is required for this response with a threshold at a submicromolar concentration. Red light stimulates an increase in the total concentration of intracellular calcium in the spores as determined by atomic absorption spectroscopy. Subsequent exposure to far-red light inhibits the red light-induced increase in intracellular calcium. The majority of the increase occurs 5 minutes after the onset of irradiation. The calcium-antagonist, La/sup 3 +/ inhibits both germination and the red light-induced increase in intracellular calcium. Using /sup 31/P-nuclear magnetic resonance spectroscopy, the author tested the hypothesis that a sustained increase in intracellular pH contributes to the ...

1985-01-01

277

The influence of aging on the intergranular corrosion of 22 chromium-5 nickel duplex stainless steel  

International Nuclear Information System (INIS)

Duplex stainless steels are widely used in severe corrosion environments because of their good corrosion performance. This paper deals with the influence of aging treatments on the intergranular corrosion (IGC) resistance of a commercial duplex stainless steel, SAF 2205. Duplex stainless steel was given aging treatments in the range 773-1173 K for time periods ranging from 6 min to 100 h. Optical microscopy and XRD was carried out on the aged stainless steels for the microstructural study. The aged samples were evaluated for the IGC susceptibility with the ASTM standard practices. Potentiodynamic cyclic polarization studies were also carried out to investigate the influence of aging treatments on the passivity breakdown. The results indicate that the sigma phase gets precipitated and is responsible for grain boundary attack. (author).

278

Predatory senescence in ageing wolves  

British Library Electronic Table of Contents (United Kingdom)

Abstract It is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long-lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal data from repeated observations of individually-known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to demonstrate that adult predatory performance declines with age and that an increasing ratio of senescent individuals in the wolf population depresses the rate of prey offtake. Because this ratio fluctuates independently of population size, predatory senescence may cause wolf populations of equal size but different age structure to have d...

2009-01-01

279

Suppressive effects of cadmium on neurons and affected proteins in cultured developing cortical cells  

International Nuclear Information System (INIS)

The purpose of the present study was to examine the in vitro effects of low-dose cadmium (Cd) on developing cortical cells. The cortical cells removed from fetuses (embryonic day 15) were treated with 10 nM of Cd for 24 h. The effects of Cd on dendritic and synaptic development were immunocytochemically observed with anti-microtubule associated protein-2 (MAP2) and anti-synapsin I antibodies, respectively. Administration of Cd suppressed dendritic as well as synaptic development at 10 nM. By two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometric (LC/MS/MS) analysis, we identified three proteins with different expression after Cd-treatment; dihydropyrimidinase-related protein 2 (DRP-2/CRMP-2), 14-3-3-epsillon and calmodulin (CaM). Though the number of identified proteins was small, these proteins are known to be involved in neuronal development. The present study demonstrated the morphological effects as well as affected proteins in ...

2008-11-20

280

Spectroscopic properties of Er"3"+ ions in cadmium and alkali cadmium borosulphate glasses  

International Nuclear Information System (INIS)

Spectroscopic properties of Er"3"+ : CBS (CdSO_4 + B_2O_3 and R_2SO_4 + CdSO_4 + B_2O_3, R_2SO_4 = Li_2SO_4.H_2O, Na_2SO_4, K_2SO_4 and Gd_2(SO_4)_3.8H_2O) glasses are reported. The assigned energy level data of Er"3"+(4f"1"1) in these glasses are analysed in terms of a parametrized model Hamiltonian. The standard deviations of the data fits are between 39 and 47 cm"-"1 so that the energy level schemes of the Er"3"+(4f"1"1) ions in borosulphate (CBS) glasses are reasonably well reproduced. Radiative properties for the fluorescent levels of Er"3"+ : CBS glasses are determined by using the Judd-Ofelt theory. The potential laser transitions are identified with the help of predicted radiative properties which are compared and discussed with similar results. (author).

1997-01-01

281

Recent Progress in CdTe and CdZnTe Detectors  

CERN Document Server

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and Gamma-ray detection. The high atomic number of the materials (Z_{Cd} =48, Z_{Te} =52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg ~ 1.5 eV) allows us to operate the detector at room temperature. However, a considerable amount of charge loss in these detectors produces a reduced energy resolution. This problem arises due to the low mobility and short lifetime of holes. Recently, significant improvements have been achieved to improve the spectral properties based on the advances in the production of crystals and in the design of electrodes. In this overview talk, we summarize (1) advantages and disadvantages of CdTe and CdZnTe semiconductor detectors and (2) technique for improving energy resolution and photopeak efficiencies. Applications of these imaging detectors in ...

2001-01-01

282

Preparation of immission dust samples for the analysis of toxic substances in dust by atomic emission spectroscopy with inductively coupled plasma  

International Nuclear Information System (INIS)

Samples of air-dust-concentration- and air-dust-deposit measurements were digested by a standardized wet digestion procedure and the amounts of substances in the dust according to class I TA Luft by Atomic Emission Spectroscopy with Inductively Coupled Plasma (AES-ICP). The characteristic values for procedures according to VDI 2449, sheet 1, were determined for lead, vanadium, cadmium, chromium, copper, nickel and zinc. By partial automatic control of the digestion procedure the personel expenditure of work could be reduced by a factor 13. Dust filter samples were analysed without sample preparation by evaporating the material with a solid state laser. The absolute detection limit was between 1 and 100 ng/cm"2 for the elements arsenic, cadmium, cobalt, chromium, mercury, antimony, selen and thallium. For sampling by means of the Beta-Staubmeter the relative detection limits for the laser-ICP were 10-fold lower than by use of a nebulizer. ...

283

Microprocessor-controlled anodic stripping voltammeter for trace metal analysis in tap water  

Energy Technology Data Exchange (ETDEWEB)

The construction and use of a portable, microprocessor controlled anodic stripping voltameter for on-site simultaneous metal analysis of copper, lead and cadmium in tap water is discussed. The instrumental system is comprised of a programmable controller which permits keying in analytical parameters such as sparge time and plating time: a rotating cell for efficient oxygen removal and amalgam formation; and, data handling via a minicomputer or analog pen recorder. Plating and stripping potentials are controlled by a digital potentiostat; stripping is done using a staircase waveform with measurement of the current after a one msec delay. In this way charging current effects are minimized. Results of tap water analysis showed 3 +- 1 ..mu..g/L lead, 22 +- 0.3 ..mu..g/L copper, and less than 0.2 ..mu..g/L cadmium for a Berkeley, California tap water, and 1-1000 ..mu..g/L Cu, 1 -2 ..mu..g/L Pb for ten samples of Seattle, Washington tap water. ...

1984-06-01

284

High power nickel - cadmium cells with fiber electrodes (FNC)  

International Nuclear Information System (INIS)

Nickel cadmium batteries differ greatly in their mechanical design and construction of the electrodes. Using available electrode constructions, batteries are designed which meet the requirements of specific applications and offer optimum performance. Pocket- and tubular cells are basically developed with the technology of the year 1895. Since then some improvements with todays technology have been made. The sintered cells use the technology of the 1930's and they are still limited to high power application. With this knowledge and the technology of today the fiber-structured nickel electrode (FNC) was developed at DAUG laboratory, a subsidiary company of Mercedes-Benz and Volkswagen. After ten years of experience in light weight prototype batteries for electric vehicles (1-2), the system was brought into production by a new company, DAUG-HOPPECKE. Characteristics of fiber electrodes: thickness and size can be easily changed; pure active materials are used; high ...

285

Experimental Evaluation And Simulation Of Multi-pixel Cadmium-zinc-telluride Hard-x-ray Detectors  

CERN Document Server

This dissertation describes the evaluation of many-pixel Cadmium-Zinc-Telluride (CdZnTe) hard-X-ray detectors for future use with the High Energy Replicated Optics (HERO) telescope being developed at Marshall Space Flight Center. The detector requirements for the HERO application are good energy resolution (sufficient to resolve cyclotron features and nuclear lines), spatial resolution of ∼200 μm, minimal charge loss of absorbed X rays, and minimal sensitivity to the background environment. This research concentrates on assessing the suitability of these detectors for the focus of HERO, and includes the development of a simulation of the physics involved in an X-ray-detector interaction, a study of the intrinsic material properties, measurements with prototype detectors such as the energy and spatial resolution, charge loss, and X-ray background reduction through 3-dimensional depth sensing. Two types of detectors were available for evaluation. The ...

2004-01-01

286

Apoferritin Templated Synthesis of Metal Phosphate Nanoparticle Labels for Electrochemical Immunoassay  

Energy Technology Data Exchange (ETDEWEB)

W have introduced template-synthesized metal phosphate nanoparticle labels for electrochemical immunoassay. Such use of an apoferritin template offers a simple and convenient route to prepare metallic nanoparticle labels for electrochemical immunoassays and avoid the complicated and time-consuming nanoparticle synthesis process (QD synthesis). Releasing metal ions from metal phosphate in an acetate buffer (pH 4.6) eliminates the harsh condition in the traditional metallic nanoparticle dissolution (e.g., strong acid dissolution of QDs and gold nanoparticles). This method is ultrasensitive and its DL is low to 77fM. The simultaneous detection of multiple protein targets is easily performed by using different metal phosphate nanoparticle labels (cadmium phosphate and lead phosphate). This approach can be extended to prepare multiple metal (such as zinc, lead, cadmium, copper, indium, gold, silver) phosphate nanoparticle labels or hybrid metal ...

2006-08-29

287

A 1500-year record of lead, copper, arsenic, cadmium, zinc level in Antarctic seal hairs and sediments  

Energy Technology Data Exchange (ETDEWEB)

To reconstruct the profiles of heavy metal levels in the South Ocean ecosystem of Antarctica, the concentrations of lead (Pb), copper (Cu), arsenic (As), cadmium (Cd), and zinc (Zn) in seal hairs and lake sediments spanning the past 1500 years from Fildes Peninsula of King George Island and in weathering lake sediments from Nelson Island of West Antarctica were determined. The lead contents in the seal hairs and the weathering sediments show a sharp increase since the late 1800s, very likely due to anthropogenic contamination from modern industries. After the 1980s, the Pb content in seal hairs dropped by one-third, apparently due to the reduced usage of leaded gasoline in the Southern Hemisphere. Copper arises mainly from the weathering process, and its level may be substantially affected by climatic conditions. The concentrations of Cd, As, and Zn do not show any clear temporal trends.

2006-12-01

288

X-ray diffraction evaluation of the structural perfection of cadmium telluride single crystals  

Science.gov (United States)

A high degree of structural perfection is an essential requirement for CdTe crystals used as substrates for the epitaxial growth of CdHgTe alloys. Here, a method for the evaluation of the structural perfection of CdTe crystals is proposed which is based on X-ray diffraction measurements using both two-crystal and three-crystal diffractometers (differential version). The method makes it possible to obtain more information on structural perfection both at the crystal surface and within the crystal body.

1988-08-01

289

Trace metals in tap water from Tehran, Iran  

Energy Technology Data Exchange (ETDEWEB)

A total of 272 tap water samples were collected from 68 homes throughout the city of Tehran. Analysis for cadmium, zinc, lead, copper, arsenic, iron and manganese showed some accumulation of these metals in household piping overnight. However, the concentration of all metals was in the parts per billion (ug/l) range and well below international standards. Heavy metals in Tehran's drinking water therefore, do not pose a significant acute health hazard. 19 references, 2 tables.

1986-01-01

290

Synthesis of CdSe nanoparticles and their effect on the antioxidant activity of Spirulina platensis and Porphyridium cruentum cells  

International Nuclear Information System (INIS)

Single-crystalline cadmium selenide nanoparticles were obtained using high-temperature solution phase synthesis (HTSPS) synthesis. X-Ray powder diffraction and transmission electron microscopy were used to confirm the crystallinity and morphology of the resulting nanoparticles. To study the action of CdSe on antioxidant activity, we selected two biotechnological important strains of microalgae: cyanobacteria Spirulina platensis and red microalgae Porphyridium cruentum. In the case of Porphyridium cruentum, the obtained results demonstrated an increase in the productivity. For Spirulina platensis, the presence of the compound in the cultivating medium decreased the productivity of cyanobacteria.

2011-07-07

291

Synthesis and characterization of nickel(II), chromium(III), cobalt(II), copper(II), zinc(II), and cadmium(II) complexes with isatin- isonicotinoylhydrazone  

International Nuclear Information System (INIS)

A few metal complexes of isatin-isonicotinoylhydrazone with Ni(II), Cr(III), Co(II), Cu(II), Zn(II) and Cd(II) have been prepared and characterized on the basis of elemental analyses, infrared and electronic spectra as well as "1H NMR spectra, conductivity and magnetic measurements. In view of the results obtained, it has been found that two molecules of isatin-isonicotinoylhydrazone are chelated to the central metal ion as bis-uninegative ONO tridentate ligand forming non-electrolytic octahedral metal complexes. (author)

1997-03-01

292

Probable role of trace elements of some medicinal plants in cardio-vascular diseases  

International Nuclear Information System (INIS)

A number of herbal drugs are used in the Unani (Greco-Arab) System of Medicine for cardiovascular diseases. The herbs were analyzed by flame AAS and ICP-AES to determine if their therapeutic actions can be associated with the elements present in them. Cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, sodium, nickel, phosphorus, lead and zinc were some of the elements which play various roles in cardiovascular affections. An effort was made to correlate the role of these elements in cardiac diseases. (Auth.). 2 tabs., 32 refs.

293

Determination of uranium and thorium concentrations in integrated circuit packaging materials  

International Nuclear Information System (INIS)

The purpose of the present research is to find a suitable technique to measure trace amounts of uranium and thorium and to determine the surface #alpha#-flux in silicon compound (SiO) used for fabrication of integrated circuit packaging materials. Among several commonly-used detecting techniques, it was found that neutron activation analysis (NAA) was most promising. The results from NAA show a large difference in uranium and thorium concentrations when cadmium and boron carbide shields are used, whereas #alpha#-flux measurements show a low #alpha#-activity, which corresponds to the trace amounts of uranium and thorium expected to be present in these materials. (author) 13 refs.; 6 figs.

294

Anodic oxide coatings on metals and anodic protection /2nd revised and enlarged edition/. Anodnye oksidnye pokrytiia na metallakh i anodnaia zashchita /2nd revised and enlarged edition/  

Energy Technology Data Exchange (ETDEWEB)

The theoretical principles underlying the formation of oxide and, in particular, anodic oxide coatings on metals produced by chemical oxidation, anodizing in solutions, and anodizing in cold plasmas are reviewed. The mechanisms and conditions of anodic oxidation are described, and the structure of anodic oxide coatings on aluminum, magnesium, beryllium, zinc, cadmium, iron, cobalt, nickel, titanium, zirconium, tantalum, and chromium alloys is examined. Attention is also given to various applictins of anodized coatings. 54 references.

1985-01-01

295

Analytical methods for heavy metals in herbal medicines  

British Library Electronic Table of Contents (United Kingdom)

Abstract Introduction - It is estimated that about 70-80% of the world's population relies on non-conventional medicine, mainly of herbal origin. However, owing to the nature and sources of herbal medicines, they are sometimes contaminated with toxic heavy metals such as lead, arsenic, mercury and cadmium, which impose serious health risks to consumers. It is critical to analyse source materials for heavy metals in order to ensure that their concentrations meet the related standards or regulations limiting their concentrations in herbal medicines. In this review, different analytical methods for analysis of heavy metals in herbal medicines are discussed. Objective - To provide a comprehensive review of the current state of the art in analytical methods used to detect heavy metals in herbal...

2011-01-01

296

An application of the analysis of variance of measures repeated in an experiment with heavy metals  

International Nuclear Information System (INIS)

A revision of some basic concepts related to the analysis of variance of repeated measures is presented within an ecological context topics such as the types of experiments in which the technique is applicable, the hypotheses of interest, and its preference over other traditional techniques such as regression and conventional analysis of variance, are discussed. As an example, the technique was successfully applied to an experiment carried out at Cienaga Grande de Santa Marta, Colombia, in which the concentration of cadmium #mu#g/g in leaves of the black mangrove Avicennia germinans was measured in several monitoring stations and throughout several sampling intervals representing seasons.

1997-11-01

297

Emplacement ages of Jurassic-Cretaceous South African kimberlites by the Rb-Sr method on phlogopite and whole-rock samples  

International Nuclear Information System (INIS)

Rb-Sr phlogopite age determinations, interpreted as emplacement ages, are reported for 15 southern African kimberlites. Jagersfontein and Rietfontein (85 and 95 Ma) have ages typical of the majority of well-known Cretaceous kimberlites, whereas somewhat older ages of about 118 to 125 Ma have been obtained for localities in the Postmasburg, Barkly West and Boshoff districts. Previous zircon ages of 90Ma for Finsch and Roberts Victor are believed to be incorrect. Two other localities in the Barkly West area have significantly younger emplacement ages of about 114 Ma relative to most Barkly West occurrences. Two off-craton kimberlites, Uintjiesberg and Mzongwana, are 100 and 150 Ma in age respectively. Swartruggens and Elandskloof have ages of 150-160 and 165 Ma respectively. A Barkly West occurrence, Klipfontein, also has ...

298

The seeded growth of calcium sulfate dihydrate crystals in NaCl solutions up to 6 m and 90 C  

Energy Technology Data Exchange (ETDEWEB)

The kinetics of calcium sulfate crystal growth is of importance in various fields, such as geochemistry, desalination technology, petroleum industry, and water and wastewater treatment. The seeded crystal growth rate of calcium sulfate dihydrate was measured as a function of supersaturation in NaCl electrolyte solutions from 0 to 6 m at temperatures of 25, 50, 70, and 90 C. The growth followed a second-order parabolic rate law with activation energies greater than 53 kJ/mol which suggested the surface reaction as the rate-limiting step. It was observed that the rate constant and the activation energy are solution composition dependent. The rate constant increases with NaCl concentration up to 3 molal and then begins to fall slightly. The activation energy dropped from 61 kJ/mol in the pure Ca-SO[sub 4]H[sub 2]O system to 53 kJ/mol in 3.0 m NaCl solutions. The electrolyte effect was similar to the crystal solubility behavior in aqueous ...

1994-03-15

299

Role of HCl in adsorption of elemental mercury vapor by calcium-based sorbents. Report for September 1998--May 1999  

Energy Technology Data Exchange (ETDEWEB)

The paper gives results of a study to identify active sites and surface functional groups that may contribute to the absorption of elemental mercury (Hg) by relatively inexpensive calcium (Ca)-based sorbents. The study investigated the formation of chlorine (Cl) sites in CA-based sorbents as well as their role and reactivity in the absorption of Hg. HCl-exposed calcium sulfate dihydrate (gypsum) exhibited a superior Hg sorption capability. Crystalline water molecules on the surface of the gypsum were confirmed to contribute indirectly to Hg uptake. These surface molecules may have absorbed HC1 through hydrogen bond formation between an oxygen atom of a crystalline water molecule and a hydrogen atom of an HCl molecule. Two adjacent, physically absorbed HCl molecules could then trap an Hg molecule through formation of a mercuric-chloride-like molecule. Significant correlations between Cl and Hg uptake by gypsum were noted.

1999-11-01

300

Role of HCl in adsorption of elemental mercury vapor by calcium-based sorbents. Report for September 1998--May 1999  

Energy Technology Data Exchange (ETDEWEB)

The paper gives results of a study to identify active sites and surface functional groups that may contribute to the absorption of elemental mercury (Hg) by relatively inexpensive calcium (Ca)-based sorbents. The study investigated the formation of chlorine (Cl) sites in CA-based sorbents as well as their role and reactivity in the absorption of Hg. HCl-exposed calcium sulfate dihydrate (gypsum) exhibited a superior Hg sorption capability. Crystalline water molecules on the surface of the gypsum were confirmed to contribute indirectly to Hg uptake. These surface molecules may have absorbed HC1 through hydrogen bond formation between an oxygen atom of a crystalline water molecule and a hydrogen atom of an HCl molecule. Two adjacent, physically absorbed HCl molecules could then trap an Hg molecule through formation of a mercuric-chloride-like molecule. Significant correlations between Cl and Hg uptake by gypsum were noted.

1999-01-01

301

Inhibition of calmodulin - regulated calcium pump activity in rat brain by toxaphene  

Energy Technology Data Exchange (ETDEWEB)

In vivo effects of toxaphene on calcium pump activity in rat brain synaptosomes was studied. Male Sprague-Dawley rats were dosed with toxaphene at 0,25,50, and 100 mg/kg/day for 3 days and sacrificed 24 h after last dose. Ca/sup 2 +/-ATPase activity and /sup 45/Ca uptake were determined in brain P/sub 2/ fraction. Toxaphene inhibited both Ca/sup 2 +/-ATPase activity and /sup 45/Ca/sup 2 +/ uptake and the inhibition was dose dependent. Both substrate and Ca/sup 2 +/ activation kinetics of Ca/sup 2 +/-ATPase indicated non-competitive type of inhibition as evidenced by decreased catalytic velocity but not enzyme-substrate affinity. The inhibited Ca/sup 2 +/-ATPase activity and Ca/sup 2 +/ uptake were restored to normal level by exogenously added calmodulin which increased both velocity and affinity. The inhibition of Ca/sup 2 +/-ATPase activity and Ca/sup 2 +/ uptake and restoration by calmodulin suggests that toxaphene may impair active calcium ...

1986-03-05

302

Inhibition of calmodulin - regulated calcium pump activity in rat brain by toxaphene  

International Nuclear Information System (INIS)

In vivo effects of toxaphene on calcium pump activity in rat brain synaptosomes was studied. Male Sprague-Dawley rats were dosed with toxaphene at 0,25,50, and 100 mg/kg/day for 3 days and sacrificed 24 h after last dose. Ca"2"+-ATPase activity and "4"5Ca uptake were determined in brain P_2 fraction. Toxaphene inhibited both Ca"2"+-ATPase activity and "4"5Ca"2"+ uptake and the inhibition was dose dependent. Both substrate and Ca"2"+ activation kinetics of Ca"2"+-ATPase indicated non-competitive type of inhibition as evidenced by decreased catalytic velocity but not enzyme-substrate affinity. The inhibited Ca"2"+-ATPase activity and Ca"2"+ uptake were restored to normal level by exogenously added calmodulin which increased both velocity and affinity. The inhibition of Ca"2"+-ATPase activity and Ca"2"+ uptake and restoration by calmodulin suggests that toxaphene may impair active calcium transport mechanisms by decreasing regulator protein ...

1986-04-13

303

Experimental investigation on denting in PWR steam generators: causes and corrective actions  

International Nuclear Information System (INIS)

Denting studies have been undertaken in order to assess the influence of the most important parameters which could initiate corrosion of the carbon steel occurring in the tube-tube support plate crevices of some PWR steam generators. Tests have been carried out in model boilers where feedwater was polluted with sea or river water. Specific effects of chloride or sulfate and influence of oxygen content, magnetite addition and pH value were investigated. In magnetite prepacked crevices, denting is obtained within 1000 hrs for seawater pollution of 0.3 ppm chloride at the blowdown. In neutral chloride or in river water, denting is observed only with oxygen addition. Denting prevention is effective in the case of an on-line addition of phosphate, boric acid, or calcium hydroxide. For denting stopping, boric acid or calcium hydroxide is efficient even with a high seawater pollution. Soaks cannot stop denting if they are not followed by an on-line ...

304

Experimental investigation on denting in PWR steam generators, causes and corrective actions  

International Nuclear Information System (INIS)

Denting studies have been undertaken in order to assess the influence of the most important parameters which could initiate corrosion of the carbon-steel occurring in the tube-tube support plate crevices of some PWR steam generators. Tests have been carried out in model boilers, feedwater being polluted with sea or river water. Specific effect of chloride or sulfate and influence of oxygen content, magnetite addition and pH value were investigated. In magnetite prepacked crevices, denting is obtained within 1000 hours for sea-water pollution of 0.3 ppm chloride at the blowdown. In neutral chloride or in river water denting is observed only with oxygen addition. Denting prevention is effective in the case of an on-line addition of phosphate, boric acid or calcium hydroxide. For denting stopping, boric acid or calcium hydroxide is efficient even with a high sea-water pollution. Soaks cannot stop denting if they are not followed by an on-line ...

1985-03-01

305

Crystallization fouling of calcium sulfate dihydrate on heat-transfer surfaces  

Energy Technology Data Exchange (ETDEWEB)

The present paper deals with the fouling process of calcium sulfate dehydrate on heat-transfer surfaces. The crystallization of calcium sulfate showed typical asymptotic fouling curves, the asymptotic value of which was greatly influenced by the surface temperature and fluid velocity. The fouling mechanism was discussed with a generalized fouling model and proved to be surface process controlled, where the activation energy was 6.2 {times} 10{sup 4} J/mol. The availability of mechanical cleaning against the formed scale was quantitatively evaluated by applying the particle abrasion method. The removal test verified that the removing rate per unit particle concentration decreased in an inverse proportion to the overall particle load, to the power of 0.8, and that it was affected by the fluid velocity. The observed final residual fouling resistance decreased asymptotically with an increase in particle concentration. The suitable concentration of ...

1996-02-01

306

Clear liquor scrubbing with anhydrite production. Fourth quarter 1996 technical progress report  

Energy Technology Data Exchange (ETDEWEB)

This project is part of PETC`s Advanced Power Systems Program, whose mission is to accelerate the commercialization of affordable, high- efficiency, low emission, coal-fueled electric generating technologies. A process concept - Clear Liquor Scrubbing with Anhydrite Production - was proposed and accepted by PETC as a Phase I project in its Mega-PRDA program. the project integrated three process operations - chloride control upstream of the flue gas desulfurization (FGD) system, a clear liquor process for enhanced SO{sub 2} removal performance, and production of anhydrite (anhydrous calcium sulfate) rather than calcium sulfite or gypsum (calcium sulfate dihydrate). The first step in the project was to perform batch and flow-through experiments in the laboratory to confirm theoretical calculations and preliminary laboratory results concerning anhydrite formation, these laboratory experiments were designed to prove that ...

1997-02-03

307

Calcium sulfate crystallization along citrus root channels in a Florida soil exhibiting acid sulfate properties  

Energy Technology Data Exchange (ETDEWEB)

The authors observed euhedral crystals in Manatee soil in a citrus grove in St. Lucie County, Florida. The material was identified as gypsum (CaSO/sub 4/ /times/ 2H/sub 2/O) using x-ray diffraction and infrared spectra. Photomicrography and scanning electron microscopy revealed that gypsum accumulated both in old root channels and within citrus root tissue of the Btg horizon. The subsurface horizons had elevated sulfate levels, a low initial pH, a drop (0.5 unit) in pH upon air-drying. Electrical conductivity paralleled the concentration of water-soluble sulfate. High levels of calcium and sulfate occurred for horizons above the water table. This accumulation is attributed to groundwater bearing these ions and subsequently discharging them to the overlying soil. Dead citrus roots appear to act as wicks to aid water transfer from lower to higher horizons. The roots and their empty channels provide spaces in which the gypsum can precipitate if the concentrations of ...

1988-02-01

308

An indicator, high speed method for determining the water and aqueous phase content in a hydrocarbon fuel  

Energy Technology Data Exchange (ETDEWEB)

A method and an instrument for determining the total water content in a hydrocarbon fuel using an indicator composition, which includes calcium hydride and phenolphthaleyn, are developed. The essence of the method is fixing the presence of water with its interaction with the calcium hydride and subsequent indication of the formed Ca(OH)2 using the phenolphthallen. To make the indicator composition, a hygroscopic cotton, prewashed by rectified alcohol and dried for 30 minutes at 105 degrees, is impregnated by a 1 percent alcohol solution of phenolphthaleyn and is dried in the same conditions. Then the cotton is processed by a powder form calcium hydride (a layer thickness of 0.1 to 0.2 millimeters, and a granule size of less than or equal to 80 micromters). The indicator composition is placed in a glass tube (a diameter of 4 to 7 millimeters and a length of 80 to 100 millimeters), whose ends are sealed or filled with ...

1983-01-01

309

Alternative calcium-sulfate-bearing materials as cement retarders: Part II. FGD gypsum  

Energy Technology Data Exchange (ETDEWEB)

The aim of this paper is to investigate the possible displacement of natural gypsum (CaSO{sub 4}2H{sub 2}O) in cement with an alternative setting retarder, such as the industrial by-product derived from flue gas desulfurization process called FGD gypsum. These calcium-sulfate-bearing materials (CSBM), alone or in mixtures, were ground with clinker both in laboratory and industrial scale to examine their influence on the physical and mechanical properties of cement, as well as on the industrial production line of cement. From the present work, it is extracted that the use of mixtures of sulfate-bearing materials with gypsum seems to be advantageous for the actual control of setting time. The addition of FGD gypsum increases setting time without affecting compressive strength profile. During the industrial trial, the formation of hemihydrate form of calcium sulfate dihydrate has a profound regulatory effect on the setting and strength performance ...

2004-11-01

310

Activation of fat cell adenylate cyclase by protein kinase C  

Energy Technology Data Exchange (ETDEWEB)

Purified protein kinase C (C-kinase) from guinea pig pancreas and rat brain stimulated adenylate cyclase activity in purified rat adipocyte membranes. Cyclase stimulation occurred over 100 to 1000 mU/ml of C-kinase activity, required greater than 10 ..mu..M calcium, proceeded without a lag, was not readily reversible, and required no exogenous phospholipid. Moreover, C-kinase inhibitors, such as chlorpromazine and palmitoyl carnitine, inhibited selectively adenylate cyclase which was activated by C-kinase and calcium. Depending on assay conditions, 10 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) either enhanced or was required for kinase action on cyclase. Also, TPA plus calcium promoted the quantitative association of C-kinase with membranes. Adenylate cyclase activation by C-kinase was seen both in the presence and absence of exogenous GTP, indicating that the kinase effect does not result from an action on the ...

1986-05-01

311

Present status of biological effects of toxic metals in the environment: lead, cadmium, and manganese  

Energy Technology Data Exchange (ETDEWEB)

The number of reports concerning the chemical toxicology of metals which are released in the environment by natural as well as anthropogenic sources, have been increasing constantly. Lead, cadmium, and manganese have found a variety of uses in industry, craft, and agriculture owing to their physical and chemical properties. The environmental burden of heavy metals has been rising substantially by smelter emission in air and waste sewage in water. Further, organic compounds of lead and manganese used as antiknock substances in gasoline are emitted into the atmosphere by automobile exhaustion. Such environmental contamination of air, water, soil, and food is a serious threat to all living kinds. Although these metals are known to produce their toxic effects on a variety of body systems, much emphasis has been placed on their effects on the nervous system owing to apparent association of relatively low or ''subclinical'' levels of ...

1984-08-01

312

Physical and electrochemical characterization of CdS hollow microspheres prepared by a novel template free solution phase method  

International Nuclear Information System (INIS)

Novel CdS hollow microspheres have been successfully synthesized via a facile template-free solution-phase reaction from cadmium nitrate and thioacetamide precursors. The morphology of CdS hollow microspheres depends strongly on the ratio between the precursors, cadmium nitrate to thioacetamide ratio. The physical properties of the hollow microspheres have systematically been studied by different characterization methods. The stoichiometry of the hollow microspheres studied by the energy dispersive X-ray diffraction spectroscopy confirmed that the synthesized CdS hollow microspheres are nearly stoichiometric bulk like CdS. The morphology of the hollow microspheres studied by high resolution scanning electron microscopy and transmission electron microscopy observations showed that the CdS hollow microspheres of the size of 2.5 ?m have hollow structure and are constructed by several nanoparticles of the size between 30 and 40 nm. The UV-visible ...

2010-12-15

313

The prevalence and correlates of self-reported hearing impairment in the Ibadan Study of Ageing  

UK PubMed Central (United Kingdom)

AbstractThis cohort study of 1302 persons aged ≥65 years, conducted in the Yoruba-speaking regions of Nigeria, determines the prevalence and correlates of hearing impairment (HI)...Full Text Available

2010-08-01

314

The implication of Sir2 in replicative aging and senescence in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

The target of rapamycin (TOR) pathway regulates cell growth and aging in various organisms. In Saccharomyces cerevisiae, silent information regulator 2 (Sir2) modulates cellular senescence. Moreover,...Full Text Available

315

The first long-lived mutants: discovery of the insulin/IGF-1 pathway for ageing  

UK PubMed Central (United Kingdom)

Inhibiting insulin/IGF-1 signalling extends lifespan and delays age-related disease in species throughout the animal kingdom. This life-extension pathway, the first to be defined, was discovered through...Full Text Available

2011-01-12

316

The effects of androgens and gonadotropins on testicular development in the prepubertal rat.  

UK PubMed Central (United Kingdom)

Treatment of male rat pups from five to 34 days of age with dihydrotestosterone or 5 alpha-androstane-3 alpha, 17 beta-diol, resulted in reduced testicular size at 35 days of age. This appeared to be...Full Text Available

1985-07-01

317

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

318

Survey on Aging Deterioration of Safety Related Equipment in Operating Nuclear Power Plants  

International Nuclear Information System (INIS)

As a basic research to consider aging deterioration of the operating nuclear power plant to seismic fragility analysis, aging deteriorations occurring safety related equipment of both Kori unit 1 and Wolsung unit 1, are investigated in this study. First of all, 378 and 152 safety related equipment are selected at Kori unit 1 and Wolsung unit 1 respectively. Seismic review team including seismic capability engineer, is organized and seismic walkdown is carried out using the nondestructive tests. As a results of seismic walkdown, crack is a typical aging deterioration which can reduce the seismic safety of safety related equipment and the other aging deteriorations such as concrete compressive strength, corrosion, and tightness of anchor bolt, have a much smaller influence than crack. In order to manage the aging deterioration data collected through the seismic walkdown in effective ...

1997-04-14

319

Survey on Aging Deterioration of Safety Related Equipment in Operating Nuclear Power Plants  

Energy Technology Data Exchange (ETDEWEB)

As a basic research to consider aging deterioration of the operating nuclear power plant to seismic fragility analysis, aging deteriorations occurring safety related equipment of both Kori unit 1 and Wolsung unit 1, are investigated in this study. First of all, 378 and 152 safety related equipment are selected at Kori unit 1 and Wolsung unit 1 respectively. Seismic review team including seismic capability engineer, is organized and seismic walkdown is carried out using the nondestructive tests. As a results of seismic walkdown, crack is a typical aging deterioration which can reduce the seismic safety of safety related equipment and the other aging deteriorations such as concrete compressive strength, corrosion, and tightness of anchor bolt, have a much smaller influence than crack. In order to manage the aging deterioration data collected through the seismic walkdown in effective ...

2008-02-15

320

Studies of osteoporosis in Singapore using isotope-related techniques  

International Nuclear Information System (INIS)

The main objectives of this study was to determine the bone density for the purposes of i) determining the age of peak bone mass in each study group and ii) quantifying the differences in bone density as functions of age and sex. The results of estimating the age dependence of mineral density for the femoral neck, spine and total body of healthy women and men using DEXA are given. The age changes in concentrations of major minerals and electrolytes found for compact and trabecular bones of healthy male femoral neck with regard for the wet and dry tissue calculations are represented. Information about femoral neck water content depending on the age of healthy men is tabulated. The number of performed observations and analyses is evidently insufficient to make any final decision, however some preliminary conclusions can be drawn. In accordance with DEXA results, BMD maximum for the ...

1996-10-07

321

Some highlights of research on aging with invertebrates, 2010  

UK PubMed Central (United Kingdom)

This annual review focuses on invertebrate model organisms, which continue to yield fundamental new insights into mechanisms of aging. This year, the budding yeast has been used to understand how asymmetrical...Full Text Available

2011-02-01

322

Socio-demographic and health-related factors associated with cognitive impairment in the elderly in Taiwan  

UK PubMed Central (United Kingdom)

BackgroundCognitive impairment is an age-related condition as the rate of cognitive decline rapidly increases with aging. It is especially important to better understand factors...Full Text Available

323

SirT1 brings stemness closer to cancer and aging  

UK PubMed Central (United Kingdom)

Sirtuin 1 acts in various cell processes, deacetylating both chromatin and non-histone proteins, and its role in cancer and aging has long been studied and debated. Here we discuss another aspect of...Full Text Available

324

RasGrf1 deficiency delays aging in mice  

UK PubMed Central (United Kingdom)

RasGRF1 is a Ras-guanine nucleotide exchange factor implicated in a variety of physiological processes including learning and memory and glucose homeostasis. To determine the role of RASGRF1 in aging,...Full Text Available

325

Quantitative bone scintigraphy in children and adolescents. Age dependence of skeleton uptake  

International Nuclear Information System (INIS)

French ... Orig. Title Scintigraphie osseuse quantifiee chez l'enfant et l'adolescent - repartition selon l'age des taux de fixation de diverses pieces osseuses normales.

326

Pulsars - survey of observational data  

Energy Technology Data Exchange (ETDEWEB)

The paper reviews the main observational data on pulsars, both the individual characteristics of pulsars and the properties they possess as members of the Galaxy. Consideration is then given to pulsar ages and to pulsar initial periods. An attempt is made to clarify the 'true' ages of pulsars.

1980-01-01

327

Protein stability and resistance to oxidative stress are determinants of longevity in the longest-living rodent, the naked mole-rat  

UK PubMed Central (United Kingdom)

The widely accepted oxidative stress theory of aging postulates that aging results from accumulation of oxidative damage. Surprisingly, data from the longest-living rodent known, naked mole-rats [MRs;...Full Text Available

2009-03-03

328

Physical Activity and Telomere Biology: Exploring the Link with Aging-Related Disease Prevention  

UK PubMed Central (United Kingdom)

Physical activity is associated with reduced risk of several age-related diseases as well as with increased longevity in both rodents and humans. Though these associations are well established, evidence...Full Text Available

329

Oxidative Stress and Longevity in Okinawa: An Investigation of Blood Lipid Peroxidation and Tocopherol in Okinawan Centenarians  

UK PubMed Central (United Kingdom)

Background. The Free Radical Theory of Aging mechanistically links oxidative stress to aging. Okinawa has among the world's longest-lived populations but oxidative stress in this...Full Text Available

2010-01-01

330

Opposing function of mitochondrial prohibitin in aging  

UK PubMed Central (United Kingdom)

While specific signalling cascades involved in aging, such as the insulin/IGF-1 pathway, are well-described, the actual metabolic changes they elicit to prolong lifespan remain obscure. Nevertheless,...Full Text Available

331

Natural variation in life history and aging phenotypes is associated with mitochondrial DNA deletion frequency in Caenorhabditis briggsae  

UK PubMed Central (United Kingdom)

BackgroundMutations that impair mitochondrial functioning are associated with a variety of metabolic and age-related disorders. A barrier to rigorous tests of the role of mitochondrial...Full Text Available

332

Mutation analysis of the ferritin L-chain gene in age-related cataract  

UK PubMed Central (United Kingdom)

PurposeTo investigate whether acquired somatic mutations in the iron response element of the ferritin L-chain gene account for the age-related cataract.MethodsThe...Full Text Available

333

Mechanisms of chemotherapy-induced human ovarian aging: double strand DNA breaks and microvascular compromise  

UK PubMed Central (United Kingdom)

The mechanism of chemotherapy-induced acceleration of ovarian aging is not fully understood. We used doxorubicin, a widely used cancer chemotherapeutic, in a variety of in vivo xenograft,...Full Text Available

334

Interrelationships between ambient temperature, age at calving, postpartum reproductive events and reproductive performance in dairy cows: a path analysis.  

UK PubMed Central (United Kingdom)

Path analysis was used to determine the interrelationships between ambient temperature, age at calving, postpartum reproductive events and reproductive performance in dairy cows. The data used in the...Full Text Available

1985-07-01

335

Increased superoxide in vivo accelerates age-associated muscle atrophy through mitochondrial dysfunction and neuromuscular junction degeneration  

UK PubMed Central (United Kingdom)

Oxidative stress has been implicated in the etiology of age-related muscle loss (sarcopenia). However, the underlying mechanisms by which oxidative stress contributes to sarcopenia have not been thoroughly...Full Text Available

2010-05-01

336

Hormone Receptor Status in Breast Cancer and its Relation to Age and Other Prognostic Factors  

UK PubMed Central (United Kingdom)

Background:Increasing evidence shows the importance of young age, estrogen receptor (ER), progesterone receptor (PR) status, and HER-2 expression in patients with breast cancers.Patients...Full Text Available

337

Hierarchical and serial processing in the spatial auditory cortical pathway is degraded by natural aging  

UK PubMed Central (United Kingdom)

The compromised abilities to localize sounds and to understand speech are two hallmark deficits in aged individuals. The auditory cortex is necessary for these processes, yet we know little...Full Text Available

2010-11-03

338

Heat Stress and Hormetin-Induced Hormesis in Human Cells: Effects on Aging, Wound Healing, Angiogenesis, and Differentiation  

UK PubMed Central (United Kingdom)

Accumulation of molecular damage and increased molecular heterogeneity are hallmarks of cellular aging. Mild stress-induced hormesis can be an effective way for reducing the accumulation of molecular...Full Text Available

339

Handgrip dynamometry, Cybex measurements and lean mass as markers of the ageing of muscle function.  

UK PubMed Central (United Kingdom)

Isometric handgrip force, isokinetic knee flexion and extension torque, and anthropometric data were obtained on 67 older men and women (ranging in age from 45 to 75 years, mean 59.7 years). Hydrostatic...Full Text Available

1991-12-01

340

Gender differences in metformin effect on aging, life span and spontaneous tumorigenesis in 129/Sv mice  

UK PubMed Central (United Kingdom)

Studies in mammals have led to the suggestion that hyperglycemia and hyperinsulinemia are important factors both in aging and in the development of cancer. It is possible that the life-prolonging effects...Full Text Available

341

Female rats display dose-dependent differences to the rewarding and aversive effects of nicotine in an age-, hormone-, and sex-dependent manner  

UK PubMed Central (United Kingdom)

IntroductionThe objective of this study was to examine age-, hormone-, and sex-dependent differences to the behavioral effects of nicotine using place-conditioning...Full Text Available

2009-10-01

342

Evolution of age at menarche and at onset of regular cycling in a large cohort of French women  

UK PubMed Central (United Kingdom)

BackgroundEarly exposure to ovarian hormones is considered to increase breast cancer incidence. The age at which the ovaries become functional is thus important.Full Text Available

2002-01-01

343

Embryonic anti-aging niche  

UK PubMed Central (United Kingdom)

Although functional organ stem cells persist in the old, tissue damage invariably overwhelms tissue repair, ultimately causing the demise of an organism. The poor performance of stem cells in an aged...Full Text Available

344

Effects of old age on vascular complexity and dispersion of the hepatic sinusoidal network  

UK PubMed Central (United Kingdom)

ObjectivesIn old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was...Full Text Available

2008-04-01

345

Effects of gender, age, diabetes mellitus and renal and hepatic impairment on tadalafil pharmacokinetics  

UK PubMed Central (United Kingdom)

AimsTo evaluate the effects of gender, age, diabetes mellitus, renal and hepatic impairment on tadalafil pharmacokinetics and tolerability.MethodsSix...Full Text Available

2007-01-01

346

Effects of Age on Optical Coherence Tomography Measurements of Healthy Retinal Nerve Fiber Layer, Macula and Optic Nerve Head  

UK PubMed Central (United Kingdom)

PurposeTo determine the effects of age on global and sectoral peripapillary retinal nerve fiber layer (RNFL), macular thicknesses and optic nerve head (ONH) parameters...Full Text Available

2009-06-01

347

Effect of hypophysectomy on liver nuclear ribonucleic acid synthesis in aging rats.  

UK PubMed Central (United Kingdom)

Changes in RNA synthesis in liver nuclei were observed at different ages and after hypophysectomy and hormone replacement in female Sprague-Dawley rats. As determined by the incorporation of [3H]UMP...Full Text Available

1979-12-15

348

Does Damage to DNA and Other Macromolecules Play a Role in Aging? If So, How?  

UK PubMed Central (United Kingdom)

One of the most pervasive ideas regarding the causes of aging is that longevity is constrained in large measure by damage to macromolecules. An increasing body of cellular and molecular data, generated...Full Text Available

2009-02-01

349

Diverging trends in incidence and mortality of testicular cancer in Denmark, 1943-1982.  

UK PubMed Central (United Kingdom)

Between 1943 and 1982, 5,140 new cases of testicular cancer were diagnosed in Denmark. The age-standardized incidence rate more than doubled in the period. Striking variations is seen in the age-relationship...Full Text Available

1986-04-01

350

Demographics, aging and health care: is there a crisis?  

UK PubMed Central (United Kingdom)

Will the aging of Canada's population bankrupt the health care system? In this issue (see pages 1555 to 1560) Dr. Marie Demers reports that the increase in physician service costs for elderly people...Full Text Available

1996-12-01

351

Deficiency of circadian protein CLOCK reduces lifespan and increases age-related cataract development in mice  

UK PubMed Central (United Kingdom)

Circadian clock is implicated in the regulation of aging. The transcription factor CLOCK, a core component of the circadian system, operates in complex with another circadian clock protein BMAL1. Recently...Full Text Available

352

Cumulative Inflammatory Load Is Associated with Short Leukocyte Telomere Length in the Health, Aging and Body Composition Study  

UK PubMed Central (United Kingdom)

BackgroundLeukocyte telomere length (LTL) is an emerging marker of biological age. Chronic inflammatory activity is commonly proposed as a promoter of ...Full Text Available

353

Correspondence of Ultrasound Elasticity Imaging to Direct Mechanical Measurement in Aging DVT in Rats  

UK PubMed Central (United Kingdom)

Previous ultrasound elasticity imaging experiments supported a generally accepted concept that the hardness of deep venous thrombi increases with thrombus aging. Results also showed that this...Full Text Available

2005-10-01

354

Cell kinetics of growth cartilage of achondroplastic (cn) mice.  

UK PubMed Central (United Kingdom)

Mice homozygous for the recessive gene achondroplasia (cn) aged 16 and 17 days and some homozygotes aged 22-34 days have disruptions in the growth of the proximal tibial growth plate which are due solely...Full Text Available

1985-05-01

355

Caveolin-1 as a Novel Indicator of Wound-Healing Capacity in Aged Human Corneal Epithelium  

UK PubMed Central (United Kingdom)

Excess caveolin-1 has been reported to play a role in age-dependent hyporesponsiveness to growth factors in vitro. Therefore, we hypothesized that caveolin-1–dependent hyporesponsiveness...Full Text Available

2010-11-01

356

CYP17 MspA1 Polymorphism and Age at Menarche: a Meta-Analysis  

UK PubMed Central (United Kingdom)

ObjectiveLiterature data on the effects of CYP17 MspA1 polymorphism on age at menarche (AAM) are inconsistent. To reexamine this controversy, we...Full Text Available

2008-01-01

357

Association between hair mineral and age, BMI and nutrient intakes among Korean female adults  

UK PubMed Central (United Kingdom)

This study was performed to investigate the association between hair mineral levels and nutrient intakes, age, and BMI in female adults who visited a woman's clinic located in Seoul. Dietary intakes...Full Text Available

2009-01-01

358

Antioxidant enzyme activities are not broadly correlated with longevity in 14 vertebrate endotherm species  

UK PubMed Central (United Kingdom)

The free radical theory of ageing posits that accrual of oxidative damage underlies the increased cellular, tissue and organ dysfunction and failure associated with advanced age. In support of this...Full Text Available

2010-06-01

359

Aging of the Hair Follicle Pigmentation System  

UK PubMed Central (United Kingdom)

Skin and hair phenotypes are powerful cues in human communication. They impart much information, not least about our racial, ethnic, health, gender and age status. In the case of the latter parameter,...Full Text Available

2009-07-01

360

Aging and the Social Cognitive Determinants of Physical Activity Behavior and Behavior Change: Evidence from the Guide to Health Trial  

UK PubMed Central (United Kingdom)

Part one of this study investigated the effect of aging on social-cognitive characteristics related to physical activity (PA) among adults in the baseline phase of a health promotion...Full Text Available

361

Age-Related Differences in Naturally Acquired T Cell Memory to Plasmodium falciparum Merozoite Surface Protein 1  

UK PubMed Central (United Kingdom)

Naturally acquired immunity to Plasmodium falciparum malaria in malaria holoendemic areas is characterized by the gradual, age-related development of protection against high-density...Full Text Available

362

Age-Related Deterioration of Rod Vision in Mice  

UK PubMed Central (United Kingdom)

Even in healthy individuals, aging leads to deterioration in visual acuity, contrast sensitivity, visual field, and dark adaptation. Little is known about the neural mechanisms that drive the...Full Text Available

2010-08-18

363

Age affects over-marking of opposite-sex scent marks in meadow voles, Microtus pennsylvanicus  

UK PubMed Central (United Kingdom)

Models of age-related effects on behavior predict that among short-lived species younger adults are more attractive and attracted to opposite-sex conspecifics than are older adults, whereas...Full Text Available

2010-01-01

364

Accumulation of Long-Chain Glycosphingolipids during Aging Is Prevented by Caloric Restriction  

UK PubMed Central (United Kingdom)

BackgroundChronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney...Full Text Available

365

A Decline in p38 MAPK Signaling Underlies Immunosenescence in Caenorhabditis elegans  

UK PubMed Central (United Kingdom)

The decline in immune function with aging, known as immunosenescence, has been implicated in evolutionarily diverse species, but the underlying molecular mechanisms are not understood. During aging...Full Text Available

2011-05-01

366

Technical-economic aspects of the utilization of geothermal waters  

International Nuclear Information System (INIS)

A brief description is given of the physico-chemical parameters characterized a hot water geothermal reservoir and of its exploitation by means of single or coupled (doublet) wells. The technical aspects of geothermal heat to the users is then discussed, beginning with corrosion of materials caused by seven main agents: oxygen, hydrogen sulphide, carbon dioxide, ammonia, hydrogen, sulphates and chlorides. A brief mention is made of scaling due to calcium carbonate, silica and calcium sulphates. The basic components of a geothermal plant for non-electric uses are then discussed: production pumps, surface pipelines, heat exchangers, heat pumps and reinjection pumps. The advantages and disadvantages of the different equipment and materials used in the geothermal sector are also presented. A list is also given of the criteria used in the energy and economic balance of a geothermal operation. (author). 24 refs, 13 figs, 2 tabs.

367

Studies on the chemical composition and possible mechanisms underlying the antispasmodic and bronchodilatory activities of the essential oil of Artemisia maritima L.  

British Library Electronic Table of Contents (United Kingdom)

This study describes the chemical composition of the essential oil of Artemisia maritima (Am.Oil) and the pharmacological basis for its medicinal use in gut and airways disorders. Twenty five compounds, composing 93.7% of the oil, were identified; among these, chrysanthenyl propionate and elixene were identified for the first time from any Artemisia species. The Am.Oil (0.3?1.0 mg/mL) suppressed spontaneous and high K+ (80 mM)-induced contractions in isolated rabbit jejunum, suggestive of an antispasmodic effect mediated possibly through calcium channel blockade. The calcium channel blockade activity was confirmed when pre-treatment of the tissue with Am.Oil (0.01?0.03 mg/mL) shifted the Ca++ concentration-response curves to the right, similar to verapamil and papaverine. In isolated trach...

2011-01-01

368

Sterilization of male stray dogs with a single intratesticular injection of calcium chloride: a dose-dependent study  

British Library Electronic Table of Contents (United Kingdom)

ObjectiveTo study a method of chemical sterilization and its efficacy in adult male stray dogs.MethodsSterilization was performed 45 days after a single bilateral intratesticular injection of calcium chloride (CaCl2) at the doses of 5, 10, 15 or 20 mg per testis per kg body weight.ResultsHistomorphological measures of testes showed total necrosis of testicular tissue at 45 days after an injection of either 10 or 15 or 20 mg CaCl2 along with fibrosis and hyalinization in seminiferous tubules and interstitial spaces. Infiltration of leucocytes was also observed with the 10- or 15-mg dose. Disintegration of germ cell arrangement in seminiferous tubules and washing out of germ cells from the tubules were noted with the 5-mg dose. Relative organ weight, epididymal sperm count, plasma and intrat...

2007-01-01

369

Scale prevention with special reference to threshold treatment  

Energy Technology Data Exchange (ETDEWEB)

Various chemical, physical, and mechanical methods to prevent unwanted deposition of mineral scale are described. The suitability of the different methods, which largely depends on the specific features and requirements of the system involved, is discussed. Special emphasis is placed upon the threshold treatment, where the growth process is retarded by the addition of trace amounts of growth inhibitors. Growth experiments have been performed on barium sulfate and calcium sulfate dihydrate seed crystals, suspended in a supersaturated solution with and without organic bisphosphonates as inhibitors. Two methods are selected for the analysis of the growth data. A degree of inhibition is defined to obtain a quantitative description of the influence of a growth inhibitor on the growth rate of the crystals. In addition the influence of the molecular structure of various bisphosphonates with different substituents is shown. The effect of a bisphosphonate on the geometry of ...

1983-01-01

370

NEW SLAG-BASED CONCRETES  

Environmental Research Database

ObjectivesTo determine the reaction rate of slag during curing and factors affecting reactivity.~%~~%~To measure the rates of chloride ingress into concrete and the extent of chloride binding.~%~~%~To determine conditions for pitting corrosion and the nature of corrosion products.~%~~%~To characterise the reactions in slag-calcium alumina cement hydration and the nature of the products.~%~DescriptionBlast-furnace slag has latent hydraulic properties, giving considerable potential for commercial use in addition to its widespread use as a partial replacement for Portland cement, notably in alkali-activated slag (AAS) and slag-calcium alumina cement (CAC) concretes. Use of AAS concretes is already well-established in China and the former USSR, but their further application is hindered by lack of research into setting, hydration and durability, Slag/CAC blends are new materials whose chemistr ...

1999-01-09

371

Jump in the air gasification rate of potassium-doped cellulosic chars  

Energy Technology Data Exchange (ETDEWEB)

Chars prepared from potassium-exchanged carboxy methyl cellulose at several heat treatment temperatures (HTTs) were gasified in air isothermally at selected gasification temperatures (GTs) in the range 633-893 K to investigate the catalytic effectiveness of potassium species. The chars displayed a noticeable jump in gasification rate at a particular gasification temperature (called jump temperature, T{sub j}). The magnitude of jump was much less than that reported for copper and nickel catalysis, but comparable with that for calcium catalysis. Increase in HTT caused a decrease in the jump temperature of chars in contrast with the increase observed in copper, nickel and calcium catalysis; also the magnitude of jump did not decrease, but remained unaltered, on increasing HTT. The different behavior of potassium catalysis is correlated to a change in the chemical state of potassium at higher HTT. The results reveal the dependence of jump ...

2010-12-15

372

Intermediate-conductance calcium-activated potassium channels participate in neurovascular coupling  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Controlling vascular tone involves K+ efflux through endothelial cell small- and intermediate-conductance calcium-activated potassium channels (KCa2.3 and KCa3.1, respectively). We investigated the expression of these channels in astrocytes and the possibility that, by a similar mechanism, they might contribute to neurovascular coupling. EXPERIMENTAL APPROACH Transgenic mice expressing enhanced green fluorescent protein (eGFP) in astrocytes were used to assess KCa2.3 and KCa3.1 expression by immunohistochemistry and RT-PCR. KCa currents in eGFP-positive astrocytes were determined in situ using whole-cell patch clamp electrophysiology. The contribution of KCa3.1 to neurovascular coupling was investigated in pharmacological experiments using electrical field stimulatio...

2011-01-01

373

Interaction studies between Crofer-22APU alloy and P2O5 containing barium calcium alumino-borosilicate (BCABS) sealant glass-ceramics  

International Nuclear Information System (INIS)

We present the effect of P2O5 addition on barium calcium aluminum borosilicate BCABS glasses of composition (mol %) 35BaO-15CaO-5Al2O3-(37-x)SiO2-8B2O3-xP2O5 (0?x?5). The incorporation of P2O5 increased network polymerization and crystallization tendency. However, addition of P2O5 leads to the formation of Cr2O3 at the interface, saturating it in the ions of the metal. This improves glass-to-metal bonding. (author)

2010-09-01

374

Calcium phosphate glass-ceramics for bioactive coating on a #beta#-titanium alloy  

International Nuclear Information System (INIS)

The formation of a porous coating is the decisive feature for the bio-compatibility of silica-free calcium phosphate glass ceramics on alloy surfaces like the #beta#-Ti structured Ti-29Nb-13Ta-4.6Zr used in this work. The ceramic composition is highly important: 50CaO-40P_2O_5-7Na_2O-3TiO_2 glass powder produces a pore-free coating unable to bind hydroxyapatite, whereas 60CaO-30P_2O_5-7Na_2O-3TiO_2 glass incorporates pores from which a crystalline hydroxyapatite phase can grow over the surface from simulated body fluid (see Figure). (Abstract Copyright [2003], Wiley Periodicals, Inc.)

2003-07-01

375

Acid-site distribution on Faujasite-type zeolites determined by n-butylamine titration--1. Comparison of the use of hammett and arylmethanol indicators on zeolites X  

Energy Technology Data Exchange (ETDEWEB)

The combined Lewis and Broensted acidities were measured of 13X (sodium) zeolite and of its 84.2% calcium-exchanged, 86.0% lanthanum-exchanged, and 69.2% protonated forms, calcined at 400/sup 0/C. The butylamine titrations were performed to visible color changes of Hammett indicators. The H/sub 0/ acidities were 0 for the sodium X zeolite, and 0.2, 0.98, and 0.75 for the calcium, lanthanum, and hydrogen zeolites, respectively. These acidities compared well with trends reported in literature for zeolites pretreated under different conditions. Titration of Broensted sites with arylmethanol indicators did not give satisfactory visible endpoints.

1980-05-29

376

A prospective randomised open label study to evaluate the potential of a new silver alginate/carboxymethylcellulose antimicrobial wound dressing to promote wound healing  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to observe both the clinical signs and symptoms of wounds at risk of infection, that is critically colonised (biofilm infected) and antimicrobial-performance of an ionic silver alginate/carboxymethylcellulose (SACMC) dressing, in comparison with a non silver calcium alginate fibre (AF) dressing, on chronic venous leg and pressure ulcers. Thirty-six patients with venous or pressure ulcers, considered clinically to be critically colonised (biofilm infected), were randomly chosen to receive either an SACMC dressing or a non silver calcium AF dressing. The efficacy of each wound dressing was evaluated over a 4-week period. The primary study endpoints were prevention of infection and progression to wound healing. The SACMC group showed a statistically significant (P = ...

2010-01-01

380

Contact Lenses  

Medline Plus

... Precautions Comprehensive Eye and Vision Examination Nutrition Lutein Antioxidants & Age-Related Eye Disease Lutein and Zeaxanthin - Eye- ...

381

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

382

Complex radiation degradation behavior of PVC materials under accelerated aging conditions  

Energy Technology Data Exchange (ETDEWEB)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the leveling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests.

1983-07-01

385

Age determination of plutonium material in nuclear forensics by thermal ionisation mass spectrometry  

International Nuclear Information System (INIS)

Age is a key parameter when deducing the history of plutonium material, i.e. the plutonium produced in the nuclear reactors. This is of vital importance, when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determine the age of plutonium material by thermal ionisation mass spectrometry using independent parent/daughter relations. This has been demonstrated for Reference Materials of known ages as well as for real samples. The already established method using gamma spectrometry is compared to this. (orig.)

2000-02-01

386

Accelerated aging tests for radiation degradation of organic materials  

International Nuclear Information System (INIS)

(Jun 1984). United States Clough, RL Gillen, KT Sandia Nat'l Laboratories

1984-06-03

387

[The indicators of biological age and accelerated aging in liquidators of the consequences of radiation emergency].  

Science.gov (United States)

The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents. PMID:21809627

2011-01-01

388

Long term accelerated aging tests on distribution cables under wet conditions  

Energy Technology Data Exchange (ETDEWEB)

Two accelerated aging test procedures are proposed for use on solid dielectric extruded distribution cables under wet conditions. One test method is a fixed time duration test in which the degree of cable specimen aging is assessed in terms of breakdown tests, while the other test method is a time to breakdown test in which the cable specimens are voltage stressed until failure ensues.

1996-10-01

389

Fundamental understanding of aging processes Review of the workshop results  

CERN Document Server

A study on the aging process of gas detectors was presented. How the development of more performing but delicate detectors, the use of faster but aggressive gases, and the need to cover large areas, led to unexpected problems was discussed. Various methods for curing aged detectors were also highlighted. (Edited abstract) 37 Refs.

2003-01-01

390

Evaluation of an eastern shale oil residue as an asphalt additive  

Energy Technology Data Exchange (ETDEWEB)

An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age-hardening and moisture susceptibility was conducted. Rheological and infrared analyses of the unaged and aged asphalts and blends were then conducted to evaluate oxidative age-hardening. 18 refs., 5 figs., 6 tabs.

1996-11-01

391

Evaluation of an eastern shale oil residue as an asphalt additive  

Energy Technology Data Exchange (ETDEWEB)

An evaluation of eastern shale oil (ESO) residue as an asphalt additive to reduce oxidative age hardening and moisture susceptibility was conducted by Western Research Institute (WRI). The ESO residue, have a viscosity of 23.9 Pa{lg_bullet}s at 60{degree}C (140{degree}F), was blended with three different petroleum-derived asphalts, ASD-1, AAK-1, and AAM-1, which are known to be very susceptible to oxidative aging. Rheological and infrared analyses of the unaged and aged asphalts and the blends were then conducted to evaluate oxidative age hardening. In addition, the petroleum-derived asphalts and the blends were coated onto three different aggregates, Lithonia granite (RA), a low-absorption limestone (RD), and a siliceous Gulf Coast gravel (RL), and compacted into briquettes. Successive freeze-thaw cycling was then conducted to evaluate the moisture susceptibility of the prepared briquettes. The ...

1995-09-01

392

Development of technical information basis of aging management for nuclear power plants  

International Nuclear Information System (INIS)

In order to implement effective safety regulations on aging management for reactor facilities etc., the information on important technology issues, the latest technical knowledge including evaluation technology, test and research outcomes, related codes and standards, regulation information, operation experiences such as accidents and trouble, etc. with respect to aging-induced deterioration in and outside Japan and in other industries, were collected, organized and evaluated. (author)

2007-08-01

393

Carbide transformations in a gamma/gamma-prime nickel alloy during prolonged aging  

Energy Technology Data Exchange (ETDEWEB)

Carbide reactions occurring in a precipitation-hardening gamma/gamma-prime Ni-Cr alloy during prolonged high-temperature aging are investigated experimentally. It is found that the decomposition of primary MC carbides, which is accompanied by the precipitation of M23C6 particles, may lead to void nucleation and growth. The effect of carbide transformations on the residual properties of the material at temperatures above the equicohesion temperature is observed at the late stages of aging only. 6 references.

1988-08-01

394

Accelerated aging tests with a resid hydrotreating catalyst  

International Nuclear Information System (INIS)

The author discusses the accelerated aging tests performed using Hondo and Maya as aging resids with a commercial large pore hydrotreating catalyst. The results from these tests were compared with those obtained under a normal full life test. The test resid was a sample of a typical refinery charge and the activities for sulfur and vanadium removal were determined at 720"0F after successive brief periods of exposure to the heavier oils.

1988-12-02

395

The influence of normal human ageing on automatic movements  

British Library Electronic Table of Contents (United Kingdom)

There is evidence that aged normal subjects have more difficulty in achieving automaticity than young subjects. The underlying central neural mechanism for this phenomenon is unclear. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the effect of normal ageing on automaticity. Aged healthy subjects were asked to practice self-initiated, self-paced, memorized sequential finger movements with different complexity until they could perform the tasks automatically. Automaticity was evaluated by having subjects perform a secondary task simultaneously with the sequential movements. Although it took more time, most aged subjects eventually performed the tasks automatically at the same level as the young subjects. Functional MRI results showed that, for bot...

2005-01-01

396

The effects of physical activity, education, and body mass index on the aging brain  

British Library Electronic Table of Contents (United Kingdom)

Abstract Normal human aging is accompanied by progressive brain tissue loss and cognitive decline; however, several factors are thought to influence brain aging. We applied tensor-based morphometry to high-resolution brain MRI scans to determine whether educational level or physical activity was associated with brain tissue volumes in the elderly, particularly in regions susceptible to age-related atrophy. We mapped the 3D profile of brain volume differences in 226 healthy elderly subjects (130F/96M; 77.9 3.6 SD years) from the Cardiovascular Health Study-Cognition Study. Statistical maps revealed the 3D profile of brain regions whose volumes were associated with educational level and physical activity (based on leisure-time energy expenditure). After controlling for age, sex, and physical...

2011-01-01

397

Proterozoic kimberlites and lamproites and a preliminary age for the Argyle lamproite pipe, Western Australia  

International Nuclear Information System (INIS)

The Argyle pipe occurring in the East Kimberley Province of Western Australia is a unique, highly-diamondiferous lamproite. Although it resembles other lamproites located in the West Kimberley Province with respect to its setting, structure, petrography and geochemistry, it is probably Proterozoic in age and hence substantially older than Tertiary occurrences of the West Kimberley Province. Rb-Sr measurements on whole rock and phlogopite samples from magmatic olivine-phlogopite lamproite, reveals a two point model age of 1126 +- 9 Ma for the Argyle pipe. This age is consistent with ages of other, similar volcanic igneous rocks occurring in several localities worldwide. The widespread occurrence of Proterozoic kimberlites and lamproites suggests that this was an important period of worldwide alkalic intrusive activity.

398

Memory of multiple aging stages above the freezing temperature in the Relaxor ferroelectric PLZT.  

Science.gov (United States)

The dynamic dielectric susceptibility and the elastic compliance of the relaxor ferroelectric lanthanum lead zirconate titanate (PLZT) 9/65/35 have been measured under different cooling and heating protocols in order to study aging and memory. The memory of multiple aging stages at different temperatures has been found (several dips in the susceptibility curves on heating), as in spin glass systems below the glass transition. Remarkably, in PLZT the memory of several aging stages is retained also above the freezing temperature deduced from the dynamic susceptibilities. The results are discussed in light of the existing models of aging and memory in spin and dipolar glasses. PMID:15447139

2004-08-24

399

Mechanical deformation and tensile super-elastic behaviors of a Ti-Mo based shape memory alloy  

Science.gov (United States)

Ni-free shape memory alloys are promising functional materials for medical applications. A newly developed Ti-Mo based shape memory alloy shows superelasticity after thermomechanical treatment. However, the microstructure evolution and precipitation during thermomechanical processes are still not well understood. In the present paper, compressive deformation behavior at a series of temperatures of 298K - 973K and tensile deformation behavior of the alloy after aged at 573K - 973K have been investigated systematically. It is found that the compressive yield stress and ultimate compressive strength change with the deformation temperature. The ultimate tensile strength and yield stress of aged specimens also change with the aging temperature following a non-linear relationship. Microstructures of aged specimens as well as effects of lattice softening and aging-induced precipitates on ...

2011-03-01

400

Mapping subcortical diffusivity. Application to brain development. Presidential award proceeding  

International Nuclear Information System (INIS)

We studied age-related microstructural changes in the subcortical white matter from adolescence to middle age in 16 healthy male subjects (age range: 12 to 47 years) using diffusion-weighted magnetic resonance (MR) imaging (DWI). Mean diffusivity (MD) of subcortical white matter was mapped onto the overlying cortical surface using our original method. The mean MD values within 76 cortical regions were measured using atlas-based gray matter segmentation and then correlated with age. A significant negative correlation with age was observed in subcortical MD values in several cortical regions, primarily over the bilateral temporal and occipital lobes. Our results demonstrated subcortical microstructural change in postadolescence that may reflect continuing myelination. (author)

2007-01-01

401

Internet use and online social support among same sex attracted individuals of different ages  

British Library Electronic Table of Contents (United Kingdom)

The current research addressed age differences in internet use among Same Sex Attracted (SSA) individuals. In general, online communities are found to be a source of social support, especially for minority group members. However, it is unclear whether younger and older SSA people differ in their use of these communities. The present research examined age differences in use of online communities, hypothesizing that young SSA people primarily use these for social interaction and support, whereas older SSA people use online communities to seek sexual contacts. Study 1 examined age differences in motives to start using these websites. Study 2 examined age differences in use of online profiles and online social support. Results of both studies confirmed our hypotheses. Younger compared to older...

2011-01-01

402

Analysis of deteriorating processes in primary circuit facilities and determination of their priorities and relevance to the lifetime of the main primary circuit components  

International Nuclear Information System (INIS)

The major degradation mechanisms acting during the aging of selected WWER-440/213 primary circuit facilities were assessed critically. The analysis gave evidence that such mechanisms include radiation and fatigue damage of the reactor pressure vessel (effect of the neutron flow, cyclic fatigue promoted by the corrosive medium, effect of thermal aging), corrosion-mechanical and thermo-mechanical (fatigue) damage of the steam generator (stress corrosion cracking, erosion corrosion, thermal aging, wear), thermal and dynamic aging of the pressurizer, and corrosion-mechanical damage of the primary circuit piping (thermal aging, corrosion). (J.B.). 5 tabs., 1 fig., 62 refs.

403

Age and gender differences in various topographical orientation strategies  

British Library Electronic Table of Contents (United Kingdom)

Orientation in the environment can draw on a variety of cognitive strategies. We asked 634 healthy volunteers to perform a comprehensive battery administered through an internet website (www.gettinglost.ca), testing different orientation strategies in virtual environments to determine the effect of age and gender upon these skills. Older participants (46-67years of age) performed worse than younger participants (18-30 or 31-45years of age) in all orientation skills assessed, including landmark recognition, integration of body-centered information, forming association between landmarks and body turns, and the formation and use of a cognitive map. Among all tests, however, the ability to form cognitive maps resulted to be the significant factor best at predicting the individuals' age group. ...

2011-01-01

404

Use of Eu"3"+ as an oxygen environment probe in alkali-alkaline earth-lanthanide phosphates with the #beta#-K_2SO_4 structure  

International Nuclear Information System (INIS)

The use of europium as a local structural probe allows the various phases appearing in the NaCaPO_4-Na_3Eu(PO_4)_2 and NaSrPO_4-Na_3Eu(PO_4)_2 systems to be detected. The broadening of the europium emission lines in going from the calcium to the strontium phases illustrates the ease of displacement of the PO_4 groups. (Auth.).

1983-09-01

405

The relation between net calcium, alkali cation and chloride movements in red cells exposed to salicylate.  

UK PubMed Central (United Kingdom)

1. From a 150 mM-NH4 salicylate medium salicylate enters human red cells with a rate constant of 1.9 min-1 at 0 degrees C. 2. Salicylate increases the red cell permeability for Ca2+ (and Mg2+). There...Full Text Available

1979-02-01

406

Simultaneous lowering of serum phosphate and LDL-cholesterol by sevelamer hydrochloride (RenaGel) in dialysis patients.  

Science.gov (United States)

The aim of the current investigation was to study the effects of sevelamer hydrochloride (RenaGel) on serum phosphate, intact parathyroid hormone levels (iPTH), and lipid profiles in stable hemodialysis patients. Hemodialysis patients maintained on calcium containing phosphate binders were enrolled in this study. Following two weeks of washout of the phosphate binders, serum phosphate rose from 6.4 +/- 0.6 to 10.5 +/- 0.7 mg/dl (p <0.001). After 8 weeks of titration with sevelamer hydrochloride, serum phosphate fell by 4.5 +/- 0.3 to 6.3 +/- 0.7 mg/dl (p <0.0001). Serum calcium levels fell during washout (9.8 +/- 0.4 to 8.9 +/- 0.3 mg/dl, p <0.004) and were unaffected by sevelamer hydrochloride. Sevelamer hydrochloride administration was associated with a 23.0 +/- 3.1% fall in total cholesterol, a 35.9 +/- 3.0% fall in LDL cholesterol, and a 35.2 +/- 5.3% fall in the LDL:HDL cholesterol ratio (p <0.001). There was no change in HDL ...

1998-12-01

407

Roles of mitochondria and temperature in the control of intracellular calcium in adult rat sensory neurons  

UK PubMed Central (United Kingdom)

SUMMARYWe recorded Ca2+ current and intracellular Ca2+ ([Ca2+]i) in isolated adult rat dorsal root ganglion (DRG) neurons at 20 and...Full Text Available

2008-04-01

408

Research on the liquefaction of lignite by hydrogenation  

Energy Technology Data Exchange (ETDEWEB)

The investigations of lignite hydroliquefaction were aimed at improving reaction control in order to minimize residue and gas portion and hence increase the oil yield. To reach this goal, the process parameters were optimized and various catalysts tested for use in sump phase hydrogenation. Detailed investigations were also carried out on the problem of calcium carbonate agglomeration and the maceral decomposition behaviour of different lignite samples under hydrogenation conditions.

1985-01-01

409

Radioactive lead studies in the human  

International Nuclear Information System (INIS)

The differing susceptibility of individuals to the toxic effects of chronic lead exposure has never been fully understood. As the major intake of lead in the human is from food and beverages, any variation between individuals of the quantity of lead absorbed from the gut, and of the distribution and excretion of this lead, may account for the differences in individual susceptibility. The food and beverages themselves may have an influence, and to investigate their effects on absorption, distribution and excretion of lead, experiments were performed on normal subjects using a short lived radionuclide of lead, "2"0"3Pb, and instruments generally available in Nuclear Medicine. Lead absorption between different individuals showed a wide variation when "2"0"3Pb was taken as a single dose between meals. Minerals were found to be mainly responsible for affecting absorption when one subject ingested "2"0"3Pb in control meals from which one dietary constituent at a time was omitted. ...

410

Photolysis of the novel inotropes EMD 57033 and EMD 57439: evidence that Ca2+ sensitization and phosphodiesterase inhibition depend upon the same enantiomeric site.  

UK PubMed Central (United Kingdom)

1. We studied the effects of flash photolysis on the novel enantiomeric cardiac inotropes EMD 57033 (a calcium sensitizer) and EMD 57439 (a phosphodiesterase III inhibitor) in rat isolated ventricular...Full Text Available

1996-08-01

411

Perlinhibin, a Cysteine-, Histidine-, and Arginine-Rich Miniprotein from Abalone (Haliotis laevigata) Nacre, Inhibits In Vitro Calcium Carbonate Crystallization  

UK PubMed Central (United Kingdom)

We have isolated a 4.785 Da protein from the nacreous layer of the sea snail Haliotis laevigata (greenlip abalone) shell after demineralization with acetic acid. The sequence of 41...Full Text Available

2007-08-15

412

Pathophysiology of incomplete renal tubular acidosis in recurrent renal stone formers: evidence of disturbed calcium, bone and citrate metabolism  

DEFF Research Database (Denmark)

Urinary acidification, bone metabolism and urinary excretion of calcium and citrate were evaluated in 10 recurrent stone formers with incomplete renal tubular acidosis (iRTA), 10 recurrent stone formers with normal urinary acidification (NUA) and 10 normal controls (NC). Patients with iRTA had lower plasma standard bicarbonate after fasting (P <0.01) and lower urinary excretion of titratable acid (P <0.05) and citrate (P <0.01) compared with NUA patients and NC, and higher urinary excretion of ammonia (P <0.05) compared with NC (P <0.05). Hypercalciuria was found in 6 of 10 patients with iRTA compared with 3 of 10 with NUA, and 0 of 10 NC. The citrate/calcium ratio in urine was significantly reduced in iRTA compared with the value in NUA (P <0.01), and in NUA compared with NC (P <0.05). Biochemical markers of bone formation (serum osteocalcin) and bone resorption (urinary hydroxyproline) were significantly increased in iRTA ...

1993-01-01

413

Magnesium Sensitizes Slow Vacuolar Channels to Physiological Cytosolic Calcium and Inhibits Fast Vacuolar Channels in Fava Bean Guard Cell Vacuoles1  

UK PubMed Central (United Kingdom)

Vacuolar ion channels in guard cells play important roles during stomatal movement and are regulated by many factors including Ca2+, calmodulin, protein kinases, and phosphatases....Full Text Available

1999-11-01

414

Involvement of protein kinase C in the mechanism of action of Escherichia coli heat-stable enterotoxin (STa) in a human colonic carcinoma cell line, COLO-205  

International Nuclear Information System (INIS)

The present study was undertaken to determine the involvement of calcium-protein kinase C pathway in the mechanism of action of Escherichia coli heat stable enterotoxin (STa) apart from STa-induced activation of guanylate cyclase in human colonic carcinoma cell line COLO-205, which was used as a model cultured cell line to study the mechanism of action of E. coli STa. In response to E. coli STa, protein kinase C (PKC) activity was increased in a time-dependent manner with its physical translocation from cytosol to membrane. Inhibition of the PKC activity in membrane fraction and inhibition of its physical translocation in response to IP_3-mediated calcium release inhibitor dantrolene suggested the involvement of intracellular store depletion in the regulation of PKC activity. Among different PKC isoforms, predominant involvement of calcium-dependent protein kinase C (PKC#alpha#) was specified using isotype-specific ...

2005-08-01

415

Inactivating calcium-sensing receptor mutations in patients with primary hyperparathyroidism.  

Science.gov (United States)

Objective:? Primary hyperparathyroidism (HPT) is characterised by autonomous secretion of PTH from enlarged parathyroid glands leading, in most patients, to asymptomatic hypercalcaemia. Familial hypocalciuric hypercalcaemia (FHH) is an autosomal dominant disorder caused by inactivating mutations in the calcium sensing receptor (CaSR) gene; it is characterised by lifelong and usually asymptomatic hypercalcaemia. Establishing the correct diagnosis is important because surgery can be curative in HPT, but ineffective in FHH. There is overlap in the diagnostic criteria for the two disorders and some patients carrying inactivating mutations in the CaSR gene, which is suggestive of FHH, also have HPT with hyperplastic parathyroid glands or adenomas. Design and Patients:? CaSR gene mutations were analyzed and clinical and biochemical parameters evaluated in 139 consecutive out-patients presenting with hypercalcaemia and suspected of having HPT. Results:? Six different ...

2011-03-29

416

Gastrointestinal absorption of lead in chicks: involvement of the cholecalciferol endocrine system  

Energy Technology Data Exchange (ETDEWEB)

The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of /sup 203/Pb and /sup 47/Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol (1,25(OH)/sub 2/D/sub 3/) as their only source of the vitamin, the absorption of both /sup 47/Ca and /sup 203/Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in /sup 47/Ca and /sup 203/Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the ...

1984-04-01

417

Gastrointestinal absorption of lead in chicks: involvement of the cholecalciferol endocrine system  

International Nuclear Information System (INIS)

The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of "2"0"3Pb and "4"7Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol [1,25(OH)_2D_3] as their only source of the vitamin, the absorption of both "4"7Ca and "2"0"3Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in "4"7Ca and "2"0"3Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the birds were repleted with ...

418

Gamma interferon induces rapid and coordinate activation of mitogen-activated protein kinase (extracellular signal-regulated kinase) and calcium-independent protein kinase C in human monocytes.  

UK PubMed Central (United Kingdom)

Gamma interferon plays an important role in regulating the functional properties of mononuclear phagocytes. In the present study, the role of activated protein kinases in the mechanism of action of...Full Text Available

1994-07-01

419

Effect of secondary fuels and combustor temperature on mercury speciation in pulverized fuel co-combustion: part 1  

Energy Technology Data Exchange (ETDEWEB)

The present work mainly involves bench scale studies to investigate partitioning of mercury in pulverized fuel co-combustion at 1000 and 1300{sup o}C. High volatile bituminous coal is used as a reference case and chicken manure, olive residue, and B quality (demolition) wood are used as secondary fuels with 10 and 20% thermal shares. The combustion experiments are carried out in an entrained flow reactor with a fuel input of 7-8 kWth. Elemental and total gaseous mercury concentrations in the flue gas of the reactor are measured on-line, and ash is analyzed for particulate mercury along with other elemental and surface properties. Animal waste like chicken manure behaves very differently from plant waste. The higher chlorine contents of chicken manure cause higher ionic mercury concentrations whereas even with high unburnt carbon, particulate mercury reduces with increase in the chicken manure share. This might be a problem due to coarse fuel particles, low surface area, and iron ...

2007-08-15

420

Differential Roles for STIM1 and STIM2 in Store-Operated Calcium Entry in Rat Neurons  

UK PubMed Central (United Kingdom)

The interaction between Ca2+ sensors STIM1 and STIM2 and Ca2+ channel-forming protein ORAI1 is a crucial element of ...Full Text Available

421

Dietary calcium and magnesium intakes and the risk of type 2 diabetes: the Shanghai Women's Health Study123  

UK PubMed Central (United Kingdom)

Background: Diet plays a key role in the development of type 2 diabetes (T2D), but little is known about the contributions of specific nutrients in populations in which dietary patterns...Full Text Available

2009-04-01

422

Autocrine regulation of T-cell activation by ATP release and P2X7 receptors  

UK PubMed Central (United Kingdom)

T-cell activation requires the influx of extracellular calcium, although mechanistic details regarding such activation are not fully defined. Here, we show that P2X7 receptors play a key...Full Text Available

2009-06-01

423

A progress for the health of south countries. The solar refrigerator; Un progres pour la sante dans les pays du Sud. Le refrigerateur solaire  

Energy Technology Data Exchange (ETDEWEB)

In order to conserve vaccines in hot countries a solar refrigerator has been made by a French university. It is a photothermal refrigerator without batteries. It uses two gases: ammonia and calcium chloride. The refrigerator is autonomous and can work eleven days without sun. (N.C.)

1998-05-01

424

A comparison of nutrient dynamics in forest ecosystems along with the Warmth Index Gradient  

Energy Technology Data Exchange (ETDEWEB)

Nutrient elements contained in litter fall flux, that of uptake flux and turnover rate had generally tended to increase with the increase in the Warmth Index, while the amount of nutrient in the A[sub 0] horizon and nutrient use efficiency did not. However, it is suggested that topographic and climatic aridity, and the amount of available and exchangeable phosphorus, calcium and magnesium greatly affect the nutrient dynamics in a each forest ecosystem as the Warmth Index increases. (J.P.N.).

1993-01-01

425

A Laser-Pointer-Based Spectrometer for Endpoint Detection of EDTA Titrations  

Science.gov (United States)

A laser spectrometer for the ethylenediaminetetra-acetic acid (EDTA) titration of magnesium or calcium ions that is designed around a handheld laser pointer as the source and a photoresistor as the detector is developed. Findings show that the use of the spectrometer reduces the degree of uncertainty and error in one part of the EDTA titrations, however overall standard deviations depend on the skill of the student and their willingness to be careful and precise.

2004-12-01

426

Influence of animal age upon antioxidant-modified UV carcinogenesis  

International Nuclear Information System (INIS)

Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is ...

427

Effect of antioxidants on aging of nuclear plant cable insulation  

International Nuclear Information System (INIS)

The effects of various antioxidants and antioxidant concentrations on the radiation and thermal stability of EPDM and XLPE polymers used for insulation of electric cable in nuclear power plants were measured. The objective was to determine if particular antioxidants could be identified as being especially effective for stabilization against radiation aging and combined thermal and radiation aging. Elongation to rupture was used as the measure of stability. Materials were irradiated to doses up to 2 MGy (200 Mrad) at a dose rate of 200 to 300 Gy/h in the Cobalt-60 Gamma Irradiation Facility at the University of Virginia. All of the antioxidants tested, which were known to provide excellent thermal stability, also provided good stability for radiation aging and combined thermal/radiation aging, although small differences between antioxidants were noted. No antioxidant or antioxidant combination was ...

428

Effect of Aging on the Toughness of Human Cortical Bone: Evaluation by R-Curves  

Energy Technology Data Exchange (ETDEWEB)

Age-related deterioration of the fracture properties of bone, coupled with increased life expectancy, are responsible for increasing incidence of bone fracture in the elderly, and hence, an understanding of how its fracture properties degrade with age is essential. The present study describes ex vivo fracture experiments to quantitatively assess the effect of aging on the fracture toughness properties of human cortical bone in the longitudinal direction. Because cortical bone exhibits rising crack-growth resistance with crack extension, unlike most previous studies the toughness is evaluated in terms of resistance-curve (R-curve) behavior, measured for bone taken from wide range of age groups (34-99 years). Using this approach, both the ex vivo crack-initiation and crack-growth toughness are determined and are found to deteriorate with age; the initiation toughness decreases some ...

2004-10-08

429

Agonist-directed trafficking of signalling at serotonin 5-HT2A, 5-HT2B and 5-HT2C-VSV receptors mediated Gq/11 activation and calcium mobilisation in CHO cells.  

Science.gov (United States)

Several examples of agonist-directed trafficking of receptor signalling at 5-HT2A and 5-HT2C receptors have been reported that involve independent downstream transduction pathways. We now report the functional selectivity of a series of chemically diverse agonists at human (h)5-HT2A, h5-HT2B and h5-HT2C-VSV by examining two related responses, the upstream activation of Gq/11 proteins in comparison with its associated cascade of calcium mobilisation. At the h5-HT2A receptor, d-lysergic acid diethylamide (LSD) and the antiparkinsonian agents lisuride, bromocriptine and pergolide exhibit a higher potency for Gq/11 activation than calcium release in contrast with all the other tested ligands such as 5-HT, mCPP and BW723C86, that show an opposite preference of signalling pathway. Comparable observations are made at h5-HT2B and h5-HT2C-VSV receptors, suggesting a similar mechanism of functional selectivity for the three serotonin receptors. ...

2008-07-30

430

Technical evaluation of Solar Cells, Inc., CdTe module and array at NREL  

Energy Technology Data Exchange (ETDEWEB)

The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

1996-05-01

431

Specific features and mechanisms of photoluminescence of nanostructured silicon carbide films grown on silicon in vacuum  

British Library Electronic Table of Contents (United Kingdom)

The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates under conditions of decreased growth temperatures (T gr ? 900?700?C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously, a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium laser (?excit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (?3 eV) region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements is split into a set of Lorentzian components. Th...

2011-01-01

432

Some lessons learned from the DOE site operator program  

Energy Technology Data Exchange (ETDEWEB)

Performance of electric vehicles (EVs) is being studied in an ongoing Site Operator Program, as part of the Electric and Hybrid Vehicle Program supported by the U.S. Department of Energy (DOE). More than 200 EVs are being operated by Site Operators in various geographical and climatic regions of the United States. Cold-weather operation of EVs is of particular interest. As expected, low temperatures affect a battery`s ability to accept a charge, which decreases EV range and increases operating costs. Battery types other than lead-acid are being evaluated such as nickel-iron, gelled electrolyte lead-acid, nickel-cadmium, and sodium-sulfur. Also, improved methods of collecting EV performance data are being implemented, thermal management systems are being tested, and a prototype ultracapacitor is being tested as a possible alternative to conventional batteries.

1995-01-01

433

Report on breast milk examinations carried out in Lower Saxony from 1987 until 1990  

International Nuclear Information System (INIS)

In the group of persistent aromatic hydrocarbons, the highest values were determined for polychlorinated biphenyls (PCB), total DDT and hexachlorobenzene (HBC). Comparisons of the relevant median values for the past six years led to the conclusion that the steep initial decline in the breast milk concentrations of DDT and HBC was followed by reductions at a much lower pace in the years after 1987. The time course of the concentration of the total PCB did not appear to follow any particular pattern. The mean contents of lead and cadmium remained by a wide margin below the threshold values for these heavy metals and thus were of no relevance from the toxicological point of view. It was found that the 134 and 137 cesium isotopes constituted no particular health hazard for breast-fed infants, as the relevant concentrations in breast milk were low. (VHE).

434

Relationships between hepatic trace element concentrations, reproductive status, and body condition of female greater scaup  

British Library Electronic Table of Contents (United Kingdom)

We collected female greater scaup (Aythya marila) on the Yukon-Kuskokwim Delta, Alaska during two breeding seasons to determine if concentrations of 18 trace elements in livers and eggs were elevated and if hepatic concentrations correlated with body condition or affected reproductive status. Fifty-six percent, 5%, and 42% of females, respectively, had elevated hepatic cadmium (Cd: >3mgg-1 dry weight [dw]), mercury (Hg: >3mgg-1dw), and selenium (Se: >10mgg-1dw). Somatic protein and lipid reserves were not correlated with hepatic Cd or Hg, but there was a weak negative correlation between protein and Se. Hepatic Cd, Hg, and Se were similar in females that had and had not initiated egg production. In a sample of six eggs, 33% and 100%, respectively, contained Se and Hg, but concentrations we...

2009-01-01

435

Private power in the country -- a chronology  

Energy Technology Data Exchange (ETDEWEB)

The chronology of installing solar power in a rural area of Ontario is described. The installation took all of seven years, and was characterized by a lot of joy, but also a lot of heartache and hardship, all of which are chronicled in this article. The project started with four solar modules generating 300 watts, nickel cadmium batteries of 225 Ah, an inverter of 600 watt, and a three-cylinder 6.5 Kw water-cooled propane generator. Today, nearly seven years later, the installation consists of 18 solar modules supplying 1350 watts of power, lead-acid batteries of 2770 Ah, a 2500 watt inverter, a one cylinder, 5.5 kw propane-gasoline generator, a heated, underground generator house, complete with an amp-hour meter and MPPT charge controller.

2003-06-30

436

Pilot project ''measurement of efficacy'' - biological monitoring of antimony pollution in the Munich test area using a standardized grass culture  

International Nuclear Information System (INIS)

This pilot project was carried out for the purpose of testing methods for active biological monitoring. It covered a period of three years (until September 1994), including two years of exposure. The measurements served to determine pollutant levels in plants used as animal fodder and dust-borne heavy metal concentrations in different sites and, on this basis, to obtain indirect information on human exposure. Among others, the pilot project investigated the suitability of Italian rye-grass as a biological indicator for aluminium, arsenic, cadmium, cobalt, chromium, copper, iron, mercury, magnesium, manganese, nickel, lead, platinum, antimony, titanium, and zinc. (orig./GL).

437

Liquid metal flow measurement by neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead-bismuth eutectic was used as a working fluid. Particles made from a gold-cadmium intermetallic compound (AuCd{sub 3}) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than l/e and the particle size of the tracer was larger than one image element size digitized for the image processing. (orig.).

1996-07-21

438

Liquid metal flow measurement by neutron radiography  

International Nuclear Information System (INIS)

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead-bismuth eutectic was used as a working fluid. Particles made from a gold-cadmium intermetallic compound (AuCd_3) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than l/e and the particle size of the tracer was larger than one image element size digitized for the image processing. (orig.).

1996-07-01

439

Influence of Dopants on Characteristics of X-Ray Detectors Fabricated from Indium-, Gallium-, and Chlorine-Doped Cadmium Telluride Single Crystals  

Science.gov (United States)

Counting characteristics of X-ray detectors fabricated from indium-doped, gallium-doped, and chlorine-doped CdTe have been investigated. The detectors fabricated from indium-doped and gallium-doped crystals showed radiation-induced polarization, namely, a progressive decrease of count rate with an increase of photon fluence in the high-photon-fluence region, while the detectors fabricated from chlorine-doped crystals did not. Results from current-voltage characteristics of the detectors indicated that the different counting characteristics of these detectors originated from the difference in internal electric fields in each detector.

1995-08-01

440

Hydrogen transport and embrittlement in 300 M and AerMet100 ultra high strength steels  

Energy Technology Data Exchange (ETDEWEB)

This paper describes how hydrogen transport affects the severity of hydrogen embrittlement in 300 M and AerMet100 ultra high strength steels. Slow strain rate tests were carried out on specimens coated with electrodeposited cadmium and aluminium-based SermeTel 1140/962. Hydrogen diffusivities were measured using two-cell permeation and galvanostatic charging methods and values of 8.0 x 10{sup -8} and 1.0 x 10{sup -9} cm{sup 2} s{sup -1} were obtained for 300 M and AerMet100, respectively. A two-dimensional diffusion model was used to predict the hydrogen distributions in the SSR specimens at the time of failure. The superior embrittlement resistance of AerMet100 was attributed to reverted austenite forming around martensite laths during tempering.

2010-05-15

441

Effects of Copper, Cadmium, and Zinc on the Hatching Success of Brine Shrimp (Artemia franciscana)  

British Library Electronic Table of Contents (United Kingdom)

Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28??g l?1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14??g l?1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were ...

2006-01-01

442

Determination of selected microelements in polish herbs and their infusions  

Energy Technology Data Exchange (ETDEWEB)

Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

2007-08-01

443

Characteristics and development report for the T1576 power supply and the MC3935 battery  

Energy Technology Data Exchange (ETDEWEB)

This report describes the requirements, designs, performance, and development histories for the T1576 power supply and the MC3935 rechargeable battery. These devices are used to power Permissive Action Link (PAL) ground controllers. The T1576 consists of a stainless steel container, one SA3553 connector, and one MC3935 battery. The MC3935 is a vented nickel/cadmium battery with 24 cells connected in series. It was designed to deliver 5.5 Amp-hours at 25{number_sign}C and the one-hour rate, with a nominal voltage of 28 V. The battery was designed to operate for 5 years or 500 full charge/discharge cycles. The power supply is expected to last indefinitely with replacement batteries and hardware.

1993-10-01

444

Biosorption of heavy metal ions on Rhodobacter sphaeroides and Alcaligenes eutrophus H16  

Energy Technology Data Exchange (ETDEWEB)

A fundamental study of the application of bacteria to the recovery of toxic heavy metals from aqueous environments was carried out. The biosorption characteristics of cadmium and lead ions were determined with purple nonsulfur bacteria, Rhodobacter sphaeroides and hydrogen bacteria, Alcaligenes eutrophus H16 that were inactivated by steam sterilization. A simplified version of the metal binding model proposed by Plette et al. was used for the description of meal binding data. The results showed that the biosorption of bivalent metal ions to whole cell bodies of the bacteria was due to monodentate binding to two different types of acidic sites: carboxilic and phosphatic-type sites. The number of metal binding sites of A. eutrophus was 2.4-fold larger than that of R. sphaeroides.

1998-01-15

445

Apparatus for in situ determination of burnup cooling time and fissile content of an irradiated nuclear fuel assembly in a fuel storage pond  

Energy Technology Data Exchange (ETDEWEB)

A detector head for in situ inspection of irradiated nuclear fuel assemblies submerged in a water-filled nuclear fuel storage pond. The detector head includes two parallel arms which extend from a housing and which are spaced apart so as to be positionable on opposite sides of a submerged fuel assembly. Each arm includes an ionization chamber and two fission chambers. One fission chamber in each arm is enclosed in a cadmium shield and the other fission chamber is unshielded. The ratio of the outputs of the shielded and unshielded fission chambers is used to determine the boron content of the pond water. Correcting for the boron content, the neutron flux and gamma ray intensity are then used to verify the declared exposure, cooling time and fissile material content of the irradiated fuel assembly.

1985-04-09

446

A facile and green preparation of high-quality CdTe semiconductor nanocrystals at room temperature  

Energy Technology Data Exchange (ETDEWEB)

One chemical reagent, hydrazine hydrate, was discovered to accelerate the growth of semiconductor nanocrystals (cadmium telluride) instead of additional energy, which was applied to the synthesis of high-quality CdTe nanocrystals at room temperature and ambient conditions within several hours. Under this mild condition the mercapto stabilizers were not destroyed, and they guaranteed CdTe nanocrystal particle sizes with narrow and uniform distribution over the largest possible range. The CdTe nanocrystals (photoluminescence emission range of 530-660 nm) synthesized in this way had very good spectral properties; for instance, they showed high photoluminescence quantum yield of up to 60%. Furthermore, we have succeeded in detecting the living Borrelia burgdorferi of Lyme disease by its photoluminescence image using CdTe nanocrystals.

2008-06-18

447

The mediating effect of age on the relationship between Child Behavior Checklist hyperactivity scores and neuropsychological test performance.  

Science.gov (United States)

The relationship between hyperactivity and neuropsychological test performance at different age levels was examined. It was found that for young children (6 to 8 years of age, n = 90), there was no significant association between hyperactivity/attentional problems (as measured by the Hyperactivity scale of the Child Behavior Checklist) and performance on neuropsychological tasks thought to contain an attentional component (WISC-R Coding, Arithmetic, and Digit Span; WRAT Arithmetic; and the Benton Visual Retention Test). However, for older children (9 to 12 years of age, n = 92), there were significant and large negative correlations between CBC Hyperactivity scores and Coding, WRAT Arithmetic, and Benton VRT scores. Multiple regression analyses supported the above results (for Coding and WRAT Arithmetic), indicating that hyperactivity/inattention has a particularly deleterious effect on test performance (relative to ...

1988-02-01

448

Role of limited cell replicative capacity in pathological age change. A review  

Energy Technology Data Exchange (ETDEWEB)

Physiological functions are carried out by differentiated cells, with finite lifespans, which age and need to be replaced. In young individuals, tissue functions are sustained at optimal levels because cellular dysfunction and cell loss are balanced by the emergence of newly differentiated cells as stem cells and their partially differentiated descendants replicate. However, with the passage of time the mitotic rates of these cells diminish. Eventually, replications occur too infrequently to offset the loss. It is at this point that the tissue begins to show structural changes and declining function which, as they become pervasive, are identified as ageing. In this paper the theory is set forth that: (1) Diminishing mitotic activity in older tissues results from limited stem cell replicative capacity. (2) All stem cells, regardless of tissue, exhibit similar replicative patterns over time, progressing from the actively proliferating to the ...

1982-01-01

449

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging. 2  

International Nuclear Information System (INIS)

Radiation-and-thermal-combined degradation of some kinds of cable insulating and jacketing materials was evaluated by accelerated aging tests. Plasticized polyvinyl chloride (PVC), silicone rubber, crosslinked and non-crosslinked halogen-free flame-retardant polyolefins (NH-XLPO and NH-PO) and ethylene-propylene rubber (EP rubber) of experimental formulation were degraded at accelerated rates, that are 50-1000 times the degradation rate under standard conditions (e.g.; 1Gy/h, 50degC), and a method to assess the lifetime of these materials under standard conditions was studied. The degradation was investigated by measuring tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for these materials were in proportion to the increase in accelerated rate. The PVC lifetime estimated from sequential aging tests had a tendency to extend beyond that from simultaneous ...

1994-01-01

450

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging  

Energy Technology Data Exchange (ETDEWEB)

Radiation-and-thermal-combined degradation of ethylene-propylene rubber (EP rubber) and chlorosulfonated polyethylene (CSM) as cable insulating and jacketing materials were evaluated by accelerated aging tests and a method to assess the lifetime of these materials under practical application was studied. EP rubber and CSM of experimental formulation were degraded at accelerated rates, that are 50 [approx] 1000 times the degradation rate under a standard condition (1Gy/h, 50degC). The degradation was investigated by measuring the tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for both EP rubber and CSM were in proportion to increase in accelerated rate. Behaviors of elongation changes showed little difference with accelerated rate. EP rubber lifetime estimated from sequential aging test had a tendency to extend beyond that from simultaneous aging ...

1992-10-01

451

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging  

International Nuclear Information System (INIS)

Radiation-and-thermal-combined degradation of ethylene-propylene rubber (EP rubber) and chlorosulfonated polyethylene (CSM) as cable insulating and jacketing materials were evaluated by accelerated aging tests and a method to assess the lifetime of these materials under practical application was studied. EP rubber and CSM of experimental formulation were degraded at accelerated rates, that are 50 #approx# 1000 times the degradation rate under a standard condition (1Gy/h, 50degC). The degradation was investigated by measuring the tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for both EP rubber and CSM were in proportion to increase in accelerated rate. Behaviors of elongation changes showed little difference with accelerated rate. EP rubber lifetime estimated from sequential aging test had a tendency to extend beyond that from simultaneous aging ...

1992-01-01

452

Early cretaceous age of orthogneiss from the Charleston Metamorphic Group, New Zealand  

International Nuclear Information System (INIS)

Discordant U-Pb zircon isotopic data from amphibolite facies orthogneisses of the Charleston Metamorphic Group, western South Island, New Zealand, define a lower intercept age of 114#+-#18 m.y. that is interpreted as the crystallization age of the orthogneiss magmas. The upper intercept age of 1026#+-#97 m.y. reflects inherited components of Precambrian zircon derived from the source region of the magmas. The age, and whole rock chemical characteristics, indicate that the orthogneisses are part of the same phase of Early cretaceous magmatic activity that produced voluminous arc-related calc-alkaline plutonic rocks throughout western South Island. Previously published K-Ar and Rb-Sr mineral ages indicate uplift and cooling of the Charleston Metamorphic Group to less than 400deg C by 110-90 m.y. This uplift occurred as a consequence of low-angle normal faulting related to the Late ...

453

The burden of atrial fibrillation in the Netherlands  

British Library Electronic Table of Contents (United Kingdom)

Background Atrial fibrillation (AF) is the most common sustained atrial arrhythmia and it is independently associated with an increased morbidity and mortality. As a result of the high prevalence of AF, the economic and clinical impact of the disease is substantial. This study describes the economic and clinical impact of AF in the Netherlands. Methods Epidemiological data on AF in the Netherlands were projected on population estimates of the Netherlands in 2009 and combined with data on the cost of AF and its interventions. Results Overall prevalence of AF in the Netherlands is 5.5% in the population over 55?years, corresponding to about 250,000 AF patients. The prevalence increases with age, and the mean age of AF patients is 69.3?years. Incidence of AF in the Netherlands varies with age...

2011-01-01

454

Rb-Sr age of the Sundsta granite in the Western Pregothian tectonic mega-unit, south-western Sweden  

Energy Technology Data Exchange (ETDEWEB)

The Sundsta granite is a reddish, acidic granite, situated in the Western Pregothian mega-unit in Vaermland, south-western Sweden. Its Rb-Sr whole-rock age is 1566+-39 Ma with an initial ratio 0f 0.705 +-0.003. The region is dominated by grey, migmatized granitoids presumably belonging to the Aamaal-I group which has ages of 1650-1700 Ma. The marked difference in degree of migmatization between these two rock-units may indicate that the intrusion of the Sundsta granite post-dates the main migmatization phase of the Aamaal-I granitoid in this region.

1982-10-25

455

Focus on O & M  

Energy Technology Data Exchange (ETDEWEB)

A series of short articles discusses: use of a chemically bonded ceramic composite liner, WellerDensit, to protect the steel surface of pulverizer classifier cones; use of a fused cast basalt liners developed by Abresist Corp. in pipes for transporting coal and ash; a survey completed by the National Energy Technology Laboratory to identify causes of outages and other concerns expressed by PC and FBC boiler operators; and Temp-Age, Early Visc-Age and Modern Visc-Age systems for controlling the viscosity of heavy fuel oil to maintain proper combustion. 7 figs.

2004-10-01

456

First experiences with application of gadolinium-DTPA in infants and small children under two years of age  

International Nuclear Information System (INIS)

The use of Gadolinium-DTPA as a paramagnetic contrast agent in MRI with adults and juveniles concerning brain and spinal cord pathology is well proven since years. In the FRG it is only introduced for children over two years of age. Therefore this report deales with the experience in four infants and small children under the age of two. They all were suffering from neurological tumors and got additional diagnostic information in three cases. Clinical side-effects like urticaria, vomiting or convulsions had not been observed nor had pathologic changes of the biochemical parameters been noticed. (orig./GDG).

457

Accelerated aging of EPDM and butyl elastomers  

Energy Technology Data Exchange (ETDEWEB)

This study was composed of three parts: a post cure study to optimize final properties of an ethylene-propylene-diene (EPDM) formulation, an accelerated aging study to compare the stress relaxation behavior of a butyl and an EPDM elastomer under compression, and a cursory evaluation of a new 70 Shore A EPDM. The optimum postcure for the EPDM was found to be 2 to 4 hours at 182{degrees}C in a vacuum. The EPDM was also shown to have superior aging characteristics compared to the butyl and is recommended for use instead of the butyl material. The physical properties for new 70 Shore A EPDM are satisfactory, and the stress relaxation behavior was only slightly inferior to the other EPDM.

1996-06-01

459

The ageing of CANDU steam generator due to localized corrosion  

International Nuclear Information System (INIS)

The Steam Generator (SG) tubing degradation caused by corrosion and other age-related mechanisms continues to be a significant safety and cost concern for many Nuclear Power Plants (NPP). The understanding of the steam generator ageing mechanisms is the key to effective management of steam generator ageing and consists of the knowledge of steam generator materials and these one properties, stressors and operating conditions, like degradation sites and wear mechanisms. The principal types of corrosion are presented which can occur in CANDU steam generator. There are also presented the operation conditions, the specifications referring to the water chemistry and the construction materials of Steam Generator, the factors that have a great influence on the corrosion behaviour during the whole exploitation period of this equipment. (R.P.)

2001-09-17

460

The Mitoscriptome in Aging and Disease  

UK PubMed Central (United Kingdom)

Mitochondria are the major sites where energy is produced in the cell. Functions of organs such as the heart which has high energy demand are seriously affected by dysfunction of mitochondria....Full Text Available

2011-04-19

461

Telomeres in cancer and ageing  

UK PubMed Central (United Kingdom)

Telomeres protect the chromosome ends from unscheduled DNA repair and degradation. Telomeres are heterochromatic domains composed of repetitive DNA (TTAGGG repeats) bound to an array of specialized...Full Text Available

2011-01-12

462

Study of age hardening behavior of Al-4.5wt%Cu/zircon sand composite in different quenching media - A comparative study  

British Library Electronic Table of Contents (United Kingdom)

The age hardening behavior of Al-4.5%Cu alloy composite reinforced with zircon sand particulates and produced by stir casting route has been investigated in different quenching media viz, water, oil, and salt brine solution (7wt%). Optical microscopy of the as cast alloy composite indicates that the matrix of the composite has the cellular structure. Copper rich CuAl2 precipitates have been found near particle matrix interface. The results of ageing demonstrate that the microhardness of age hardenable Al-Cu based alloy composites depend on the quenching medium in which they are heat treated. Salt brine quenching is faster as compared to water and oil, even if higher strength is obtained but cannot be used for complex shapes and thin sections where oil quenching is the alternative due to mi...

2009-01-01

463

Regulation of Senescence in Cancer and Aging  

UK PubMed Central (United Kingdom)

Senescence is regarded as a physiological response of cells to stress, including telomere dysfunction, aberrant oncogenic activation, DNA damage, and oxidative stress. This stress response has an antagonistically...Full Text Available

464

Radioiodide uptake in brain, CSF, thyroid, and salivary glands of audiogenic seizure mice  

Energy Technology Data Exchange (ETDEWEB)

DBA/2J (DBA) mice are susceptible to audiogenic seizures (ASs) in an age-dependent manner. Anion transport as measured by radioiodide uptake was determined in thyroid gland, salivary gland, skeletal muscle, cerebral cortex, cerebellum, brainstem, and CSF from these mice at various ages. Anion transport was also determined in C57BL/6J(C57) mice, an AS-resistant strain. In thyroid, DBA mice had an enhanced ability to concentrate iodide at 21 days of age when they have maximal AS susceptibility, as compared with the same-aged C57 mice. This difference in thyroid function was less marked at 40 days of age, when DBA mice are less AS susceptible, and was absent at 110 days of age, when DBA mice are AS resistant. In brain, differences in iodide uptake were also noted between these two strains of mice at 21 days of age. DBA mice had an increased ...

1984-08-01

465

Pioneering the nuclear age  

Energy Technology Data Exchange (ETDEWEB)

This paper reviews the historical aspects of nuclear physics. The scientific aspects of the early transuranium elements are discussed and arms control measures are reviewed. 11 refs., 14 figs. (LSP)

1988-09-01

466

Nutritional state, maturational delay on electroencephalogram, and developmental outcome in extremely low birth weight infants  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study is to clarify the relation among developmental outcome, nutritional state during the neonatal period, maturational electroencephalographic changes. Thirteen extremely low birth weight infants who completed 6- or 9-year follow-up were a subject of this study. Undernutrition was defined as enteral feeding below 100mL/kg/day at 3weeks of age. Dysmature patterns were defined as the persistence of EEG patterns 2weeks or more immature for post-conceptional age. IQ was examined at 6 and 9years of age. Body height and weight, and head circumference at 6years of age were stratified by the percentile grades. Full and verbal IQ was significantly lower in infants with undernutrition than those with normal nutrition. Among infants with undernutrition, those with persistent dysmatu...

2010-01-01

467

Nociceptive and Anxiety-Like Behavior in Reproductively Competent and Reproductively Senescent Middle-Aged Rats  

UK PubMed Central (United Kingdom)

BackgroundChanges in levels of estradiol and progesterone that occur with the transition to reproductive senescence may influence nociception or affect.Full Text Available

2009-01-01

468

Mitochondrial uncoupling and lifespan  

UK PubMed Central (United Kingdom)

The quest to understand why we age has given rise to numerous lines of investigation that have gradually converged to include metabolic control by mitochondrial activity as a major player. That...Full Text Available

2010-01-01

469

Mitigating aging in CANDU plants  

Energy Technology Data Exchange (ETDEWEB)

Aging degradation is a phenomenon we all experience throughout life, both on a personal basis and in business. Many industries have been successful in postponing the inevitable impact on their related systems and components through programs to maintain long-term reliability, maintainability and safety. However, this has not always been the case for nuclear power. While all power plants are experiencing the world trend of increasing operating costs with age, few (if any) have been able to fully define the parameters that solve the aging equation, particularly in relation to major components. Inspection and preventive maintenance have not been effective in predicting life-limiting degradation and failure. In CANDU nuclear plants, utilities are taking a comprehensive approach in dealing with the aging problem. Programs have been established to identify the current condition and degradation mechanisms of ...

1995-07-01

470

Medical Conditions of Nursing Home Admissions  

UK PubMed Central (United Kingdom)

BackgroundAs long-term nursing home care is likely to increase with the aging of the population, identifying chronic medical conditions is of particular interest. Although need factors...Full Text Available

471

Management of hyperlipidaemia: guidelines of the British Hyperlipidaemia Association.  

UK PubMed Central (United Kingdom)

There is considerable evidence to suggest that the identification and treatment of dyslipidaemia will reduce the risk of premature CHD, i.e. before the age of 65. Diagnosis of the cause of raised plasma...Full Text Available

1993-05-01

472

Lifespan extension induced by AMPK and calcineurin is mediated by CRTC-1 and CREB  

UK PubMed Central (United Kingdom)

Activating AMPK or inactivating calcineurin slows ageing in Caenorhabditis elegans1,2...Full Text Available

2011-02-17

473

Influence of thermal aging on the intergranular corrosion resistance of types 304LN and 316LN stainless steels  

International Nuclear Information System (INIS)

Intergranular corrosion (IGC) resistance of types 304LN and 316LN stainless steels (SS) thermally aged at 823, 873, and 923 K for various durations was assessed by ASTM A262 practice A test (electrolytic etch test) and electrochemical potentiodynamic reactivation (EPR) test. The results indicated that the type 316LN SS has significantly improved IGC resistance compared to 304LN SS. Based on the results of these tests, time-temperature-sensitization (TTS) diagrams were developed for both alloys. The secondary precipitates formed during thermal aging treatments were electrochemically extracted and analyzed by X-ray diffraction (XRD) to determine the types of precipitates formed during the aging treatments. The results indicated that the precipitates were mostly of M_2_3C_6 carbides.

1996-01-01

474

Influence of thermal aging on the intergranular corrosion resistance of types 304LN and 316LN stainless steels  

International Nuclear Information System (INIS)

Intergranular corrosion (IGC) resistance of types 304LN and 316LN stainless steels (SS) thermally aged at 823, 873, and 923 K for various durations was assessed by ASTM A262 practice A test (electrolytic etch test) and electrochemical potentiodynamic reactivation (EPR) test. The results indicated that the type 316LN SS has significantly improved IGC resistance compared to 304LN SS. Based on the results of these tests, time-temperature-sensitization (TTS) diagrams were developed for both alloys. The secondary precipitates formed during thermal aging treatments were electrochemically extracted and analyzed by X-ray diffraction (XRD) to determine the types of precipitates formed during the aging treatments. The results indicated that the precipitates were mostly of M_2_3C_6 carbides.

475

Improved micropower logic ... - NASA Technical Report Server (NTRS)  

Science.gov (United States)

4), is quite efficient for multivibrators because complementary outputs are available ... age or ground, much as is done in the complementary multivibrators. ...

476

If I Had - Excessive Skin Aging  

Medline Plus

... some home products, like vitamin A, glycolic acid, antioxidants, vitamin C, etc. We can use these products ...

477

Hypothalamic and dietary control of temperature-mediated longevity  

UK PubMed Central (United Kingdom)

Temperature is an important modulator of longevity and aging in both poikilotherms and homeotherm animals. In homeotherms, temperature homeostasis is regulated primarily in the preoptic area...Full Text Available

2010-01-01

478

Healthy Nutrition: Breastfeeding  

Medline Plus

Ages & Stages Prenatal Delivery & Beyond Decisions to Make Baby: 0-12 mos. Bathing & Skin Care Breastfeeding Crying & Colic Diapers & Clothing Feeding & Nutrition Preemie ...

479

Glucose Intolerance and Cardiometabolic Risk in Adolescents Exposed to Maternal Gestational Diabetes  

UK PubMed Central (United Kingdom)

OBJECTIVEAdolescent offspring of women with a history of gestational diabetes (GD) were evaluated for their cardiometabolic risks at a mean age of 15 years.RESEARCH...Full Text Available

2010-06-01

480

Fractal dynamics in physiology: Alterations with disease and aging  

UK PubMed Central (United Kingdom)

According to classical concepts of physiologic control, healthy systems are self-regulated to reduce variability and maintain physiologic constancy. Contrary to the predictions of homeostasis, however,...Full Text Available

2002-02-19

481

Dyspepsia Symptoms and Helicobacter pylori Infection, Nakuru, Kenya  

UK PubMed Central (United Kingdom)

The prevalence of Helicobacter pylori infection was studied in 138 patients with dyspepsia in a hospital in Nakuru, Kenya, and in 138 asymptomatic sex- and age-matched controls from...Full Text Available

2003-09-01

482

Digital Hearing Aids: Current "State-of-the-Art"  

Science.gov (United States)

... promise of highly advanced signal processing, ensured that digital hearing aid technology had come of age. So how far have ...

483

Dietary Restriction in Drosophila: Delayed Aging or Experimental Artefact?  

UK PubMed Central (United Kingdom)

Lifespan can be extended by reduction of dietary intake. This practice is referred to as dietary restriction (DR), and extension of lifespan by DR is evolutionarily conserved in taxonomically diverse...Full Text Available

2007-04-01

484

Current Projects - Human Nutrition Research Center on Aging ...  

Science.gov (United States)

diet and genetic obesity metabolic defects and inflammation. To determine the role of adipocyte death in promoting adipose tissue inflammation and insulin resistance in animal...

2011-08-31

485

Comorbidities of Migraine  

UK PubMed Central (United Kingdom)

Migraine is a common neurological disorder and can be severely disabling during attacks. The highest prevalence occurs between the ages of 25 and 55 years, potentially the most productive period...Full Text Available

487

Calibrating Cosmological Chronometers: White Dwarf Masses ...  

Science.gov (United States)

... The second scenario is limited by the age of our Galaxy such that the lowest-mass WD that could be formed via single star evolution is ~0.47 M ...

2011-05-14

488

CONSEQUENCES OF DOMINANCE-MEDIATED HABITAT SEGREGATION IN AMERICAN REDSTARTS DURING THE NONBREEDING SEASON  

Science.gov (United States)

... M. Taylor, T. Kurt Kyser. (2009) Feather isotope analysis discriminates age-classes of Western, Least, and Semipalmated sandpipers when plumage ... ...

489

Brain CT image and handedness of schizophrenia  

International Nuclear Information System (INIS)

Brain CT images were reviewed of 98 schizophrenic patients and 90 healthy persons in relation to handedness and aging. CT images were further reconstructed to examine morphologically subtle changes in each region. Schizophrenic patients had progressive brain atrophy and dilated lateral ventricles, especially on the left side and in the posterior part of the lateral ventricle. These findings were more marked in left-handed than in right-handed schizophrenic patients. According to age groups, there were significant differences between schizophrenic and normal persons over the age of 40. The incidence of left handedness was significantly higher in schizophrenic patients in their fourties than the age-matched normal persons (31.4% vs 15.1%). Morphological abnormality and laterality might be due to the same pathologic consequences. (N.K.).

490

BC  

Wastenet

added to provide resistance to UV degradation, and vulcanization control. ...Sulphur is used to vulcanize the rubber ...additives and solvents age resistors, processing aids, accelerators, vulcanizing agents, softeners and fillers

491

Autocatalytic nucleation of omega phase in a beta-titanium alloy  

International Nuclear Information System (INIS)

Observations concerned with the formation of isothermal #omega# in the beta-titanium alloy RMI (38-6-44) are presented as part of a more general study of the aging characteristics of the alloy.

492

Assessment of Low Quantitative Ultrasound Values of Calcaneus in Chinese Mainland Women  

British Library Electronic Table of Contents (United Kingdom)

Calcaneus quantitative ultrasound (QUS) assessment is a safe and reliable method for evaluating skeletal status. Until now, considerable data have been accumulated on the distribution of QUS in Caucasian populations, whereas such data are still insufficient in Asian populations, especially in Chinese mainland. The present study aimed to obtain the distribution characteristic of calcaneus QUS in healthy Chinese women, and to further investigate the distribution of low bone mass by QUS stiffness index (SI). This study included 2,498 healthy Chinese females aged 10-87 yr. The QUS exhibited a characteristic mild rise and then fall pattern with increasing age. Age, body height, and weight were significant influencing factors on SI, especially age and weight. The prevalence of osteoporosis detec...

2006-01-01

493

Arterial stiffness is associated with low thigh muscle mass in middle-aged to elderly men  

British Library Electronic Table of Contents (United Kingdom)

Objective: Sarcopenia of legs is an important cause of physical dysfunctions, frailty and dependence. Many predisposing and underlying mechanisms of sarcopenia, including age, sedentary life style, oxidative stress, insulin resistance, and low testosterone levels, are also known to be related to atherosclerosis, which is another leading cause of morbidity and mortality in elderly subjects. In this study, we investigated our hypothesis that sarcopenia and atherosclerosis are associated with each other to facilitate mutual abnormalities. Methods: Study was performed in apparently healthy 496 middle-aged to elderly persons recruited consecutively among the visitors to the medical check-up program, Anti-Aging Doc, in a University hospital, from March 2006 to December 2007. Mid-thigh muscle cro...

2010-01-01

494

Analyzing nutrient distribution in different particle-size municipal aged refuse  

British Library Electronic Table of Contents (United Kingdom)

To investigate the feasibility of using aged municipal solid waste as farmland soil, it is essential to study its nutritive compositions for plant growth. Previous studies have demonstrated that the properties of different particle-size aged refuse are very different, therefore, the present study was conducted to evaluate the adequacy of three elements (N, P, K) and the fractionation of inorganic P in the aged refuse with a particle-size distribution of 900 to 300, 300 to 150, 150 to 105, 105 to 90 and 90 to 0mm. The results indicate that (1) total quantities of N, P, K were much larger than that in the general soil and the quantities of available N, P and K were also adequate; (2) total content of P was sufficient, but the ratio of available-P to total P was not high enough; (3) with the ...

2011-01-01

495

Aging measurements of a TMAE-based photon detector for the HERA-B RICH  

CERN Document Server

We report on aging measurements of a photon detector candidate for the HERA-B RICH. The prototype, a proportional wire chamber operated with TMAE, was mounted on an argon filled test-beam RICH and was aged by UV light at rates we expect in HERA-B. We monitored gain and current continuously, and checked the chamber with Cherenkov photons at regular intervals. The number of detected photons/track (projected to 2.75 m C sub 4 F sub 1 sub 0 in HERA-B) dropped from 26 to 11 after two days of aging - well below the 20 required for pi/K separation. Based on these results, HERA-B decided to use multi-anode PMTs as photon detectors in the RICH.

1999-01-01

496

Aging in Language Dynamics  

UK PubMed Central (United Kingdom)

Human languages evolve continuously, and a puzzling problem is how to reconcile the apparent robustness of most of the deep linguistic structures we use with the evidence that they undergo possibly...Full Text Available

497

Accelerated aging speeds test of instrument reliability  

International Nuclear Information System (INIS)

This paper shows how molecular theory paves the way for accelerated aging tests of safety-related equipment in nuclear power plants, as required by NRC qualification programs. Arrhenius' model, based on an equation, provides useful information regarding the extent of molecular change as a function of time and temperature. Critical to determining the aging characteristics and qualified life of organic materials is the activation energy concept, which is derived from information gathered when the molecular reaction of the material is documented over the entire life cycle. In accelerated-aging applications, the importance of the model lies in characterizing the chemical related reactions of materials. The problem with the Arrhenius approach is that, in generating a testing period of reasonable duration, a rather high test temperature must be selected which may lead to an added and unrelated environmental effect.

1982-01-01

498

Accelerated aging of catalytically airblown asphalt membranes under simulated uranium mill tailings impoundment conditions  

International Nuclear Information System (INIS)

This paper evaluates the performance of asphalt membranes by examining the chemical and permeability changes experienced by the asphalt during aging tests. The aging process was accelerated by exposing the asphalt to elevated temperatures, high oxygen concentrations, and increased strengths of aqueous oxidizing agents. The synergistic effects of the variables are evaluated by using a fractional factorial experimental design. The installation costs for a catalytically airblown asphalt liner are roughly half that of the typical polymeric materials, and also less than the rubberized asphalt membrane. The results of the initial accelerated aging tests of the asphalt membranes indicate that this material will provide stable, long-term leachate isolation in a mill tailings environment.

1982-12-01

499

A Nearby Old Halo White Dwarf Candidate from the Sloan ...  

Science.gov (United States)

... than the age of the universe unless it is an unresolved double degenerate or a product of common-envelope binary star evolution (Fontaine et al. ...

2008-07-01