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1

Effects of post-harvest foliar boron and calcium applications on subsequent season's pollen germination and pollen tube growth of pear ( Pyrus pyrifolia)  

Microsoft Academic Search

The primary objective of this study was to evaluate the effects of foliar boron and calcium application after harvest on the quantity and activity of pollen in the ‘Housui’ and ‘Wonwhang’ pears on a subsequent year. Pollen grains of the ‘Housui’ pear were cultured on germination medium, to which had been added boric acid (0, 25, 75, 100, 200, 300,

Sang-Hyun Lee; Wol-Soo Kim; Tae-Ho Han

2009-01-01

2

Selenium fertilizers and foliar application, Danish experiments.  

PubMed

In 1963 Se-deficiency was observed for the first time in Denmark in a few sheep in West Jutland. The sheep were cured by injection of "Tokosel", and a survey of the Se-status of Danish fodder crops was initiated. A comprehensive set of data was produced during the early 70's, using the fluorometric method. The survey showed a general Se-deficiency in the whole country, and series of experiments were carried out to elucidate the possibility of raising the selenium level in plants from the native 0.02-0.04 ppm to more than the desired minimum of 0.05 ppm. Three different methods of application were tested: seed pretreatment, fertilizer enrichment, and foliar application. Seed pre-treatment has some disadvantages while the two other methods proved to be efficient and safe in a series of experiments and in tests on a large number of farms all over Denmark. These experiments and tests are discussed in detail. It is concluded that about 120 g Se/ha as sodium selenite, 10 g Se/ha as sodium selenate - both added through PK- or NPK-fertilizers, or foliar application of about 5 g Se/ha are sufficient yearly treatments to raise the native Se content of the Danish crops to levels of 0.05-0.1 ppm. PMID:3013073

Gissel-Nielsen, G

1986-01-01

3

Physiological mechanisms drive differing foliar calcium content in ferns and angiosperms.  

PubMed

Recent evidence points to ferns containing significantly lower contents of foliar calcium and other cations than angiosperms. This is especially true of more ancient 'non-polypod' fern lineages, which predate the diversification of angiosperms. Calcium is an important plant nutrient, the lack of which can potentially slow plant growth and litter decomposition, and alter soil invertebrate communities. The physiological mechanisms limiting foliar calcium (Ca) content in ferns are unknown. While there is a lot we do not know about Ca uptake and transport in plants, three physiological processes are likely to be important. We measured transpiration rate, cation exchange capacity, and leaching loss to determine which process most strongly regulates foliar Ca content in a range of fern and co-occurring understory angiosperm species from a montane Hawaiian rainforest. We found higher instantaneous and lifetime (corrected for leaf lifespan) transpiration rates in angiosperms relative to ferns. Ferns preferentially incorporated Ca into leaves relative to strontium, which suggests that root or stem cation exchange capacity differs between ferns and angiosperms, potentially affecting calcium transport in plants. There were no differences in foliar Ca leaching loss between groups. Among the physiological mechanisms measured, foliar Ca was most strongly correlated with leaf-level transpiration rate and leaf lifespan. This suggests that inter-specific differences in a leaf's lifetime transpiration may play a significant role in determining plant nutrition. PMID:23417161

Funk, Jennifer L; Amatangelo, Kathryn L

2013-02-16

4

Effects of Foliar Applications of a Benomyl-Oil-Water Emulsion on the Epidemiology of 'Cercospora L' Leaf Spot on Peanuts.  

National Technical Information Service (NTIS)

Foliar applications of a benomyl-oil-water emulsion suppressed the development of peanut leaf spot epidemics more effectively than foliar applications of a benomyl-water suspension. Foliar applications of an oil-water emulsion were ineffective. The benomy...

D. H. Smith F. L. Crosby

1973-01-01

5

Supplemental Foliar Potassium Applications with or without a Surfactant can Enhance Netted Muskmelon Quality  

Microsoft Academic Search

Netted muskmelon (Cucumis melo L. (Reticulatus Group)) fruit quality (ascor- bic acid, `-carotene, total free sugars, and soluble solids concentration (SSC)) is directly related to plant potassium (K) concentration during fruit growth and maturation. During reproductive development, soil K fertilization alone is often inadequate due to poor root uptake and competitive uptake inhibition from calcium and magnesium. Foliar applica- tions

Gene E. Lester; John L. Jifon; D. J. Makus

6

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

7

Benefit of foliar spray phosphorus on peanuts in relation to gypsum and phosphorus application to soil  

Microsoft Academic Search

A field experiment was conducted at Stratford Research Station, Stratford, Oklahoma to evalute the effect of foliar opray phosphorus on Spanish peanut yield (Arachis hypogea) with regard to the rates of gypsum and phosporus application to soil. Three levels of P (0, 45, and 90 kg\\/ha) and four levels of gypsum (0, 336, 672, and 1009 kg\\/ha) which consisted of

K. R. Sistani; L. G. Morrill

1989-01-01

8

Use of sucrose fatty acid esters in foliar application of urea  

Microsoft Academic Search

Although urea is a good source of nitrogen for foliar application of nitrogen, only a small amount of the urea supplied can be absorbed by the leaves. To increase the absorption of urea by the leaves, the surface must first be wetted to enable urea to penetrate the leaf cuticle or stomata (Frank 1967). The ability of a liquid to

Won Kae Choi; Motoki Ikeda; Yoshio Yamada

1989-01-01

9

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

10

Calcium Foliar Sprays for Control of Alfalfa Greening, Cork Spot, and Hard End in ‘Anjou’ Pears  

Microsoft Academic Search

New calcium (Ca) spray materials were made available to test for their possible improvement over the often-used dry form of calcium chloride products. Four orchards of mature ‘Anjou’ pears (Pyrus communis L.) were selected for the experiments. Three Ca materials were used at equal Ca rates, consisting of a dry Ca material derived from calcium chloride (Mora-leaf-Ca) with and without

J. T. Raese; S. R. Drake

2006-01-01

11

Foliar calcium concentration of potato and its relation to genotype lateness and tolerance of cyst nematodes  

Microsoft Academic Search

In field trials during three years respectively 18, 22 and 57 potato genotypes were grown on soils moderately or heavily infested with potato cyst nematodes (Globodera pallida) after soils were fumigated or not. Nematode infection increased leaf calcium contents but genotypes that were relatively tolerant of potato cyst nematodes (Globodera pallida) had lower leaf calcium concentrations on a particular sampling

A. J. Haverkort; F. J. de Ruijter; M. Boerma; M. van de Waart

1996-01-01

12

Studies on the effects of application of different foliar fertilizer materials, crop residue and inter cropping on Banana plants.  

National Technical Information Service (NTIS)

Five separate experiments were conducted at university of Khartoum demonstration farm during 1993 to 1995 under both orchard and nursery conditions to evaluate the effect of foliar application of different fertilizers, use of crop residue and intercroppin...

Y. M. Hassan

1996-01-01

13

Physiological response of onion plants to foliar application of putrescine and glutamine  

Microsoft Academic Search

Two field experiments were carried out in Egypt during two successive seasons (2007\\/2008 and 2008\\/2009). This study aimed to investigate the response of growth, yield quality and some metabolic constituents of onion (Allium cepa L. cv. ‘Giza 20’) to foliar application of putrescine (Put; 25, 50 and 100mgL?1) and glutamine (Glut; 50, 100 and 200mgL?1), the former a diamine and

A. A. Amin; Fatma A. E. Gharib; M. El-Awadi; El-Sherbeny M. Rashad

2011-01-01

14

Growth response of komatsuna ( Brassica rapa var. peruviridis) to root and foliar applications of phosphite  

Microsoft Academic Search

Soil and hydroponic culture experiments were conducted to investigate the effects of phosphite (Phi) as phosphorus (P) fertilizer\\u000a via root and foliar applications on the growth and P supply of komatsuna. In both experiments, root P treatments were combinations\\u000a of Phi and phosphate (Pi) at different Pi:Phi ratios, for a total of high P level (92 mg P pot?1; the soil

Hoang Thi Bich Thao; Takeo Yamakawa; Katsuhiro Shibata; Papa Saliou Sarr; Aung Kyaw Myint

2008-01-01

15

Respiration and microflora of the rhizosphere soil of wheat influenced by foliar application of urea  

Microsoft Academic Search

The numbers of micromycetes and bacteria were investigated with respect to oxygen consumption in the rhizosphere soil of wheat\\u000a and in non-rhizosphere soil. Plants after foliar application of urea (2 % solution) and non-treated plants were cultivated\\u000a in degraded chernozem and garden soil in a green-house. Changes in oxygen consumption by the suspensions of rhizosphere and\\u000a non-rhizosphere soils corresponded to

J. Vraný

1983-01-01

16

Cutting propagation of foliage crops using a foliar application of auxin  

Microsoft Academic Search

Rooting and initial shoot growth was evaluated on stem cuttings of four tropical ornamentals receiving no auxin treatment, a basal quick-dip in auxin (4920?M IBA + 2685?M NAA) prior to insertion into the rooting substrate, or a spray-to-drip foliar application of auxin (ranging from 4.9?M IBA + 2.7?M NAA to 492?M IBA + 269?M NAA) after insertion into the rooting

E. K. Blythe; J. L. Sibley; J. M. Ruter; K. M. Tilt

2004-01-01

17

Foliar applications of mono-potassium phosphate fertilizer inhibit powdery mildew development in nectarine trees  

Microsoft Academic Search

Foliar applications of 1% solution of mono-potassium phosphae (MKP = KH2P04) fertilizer plus Triton X-100 (0.025%), sterol inhibiting (SI) fungicides, and an alternating treatment of phosphate fertilizer and SI fungicides inhibited development of the powdery mildew fungus Sphaerotheca pannosa on fruits and leaves of nectarine trees in 3 consecutive years. The effectiveness of the alternating treatments with an appropriate systemic

M. Reuveni; R. Reuveni

1998-01-01

18

Effect of Foliar Salicylic Acid Applications on Growth, Chlorophyll, and Mineral Content of Cucumber Grown Under Salt Stress  

Microsoft Academic Search

The objective of this study was to determine the effect of foliar salicylic acid (SA) applications on growth, chlorophyll, and mineral content of cucumber grown under salt stress. The study was conducted in pot experiments under greenhouse conditions. Cucumber seedlings were treated with foliar SA applications at different concentrations (0.0, 0.25, 0.50, and 1.00 mM). Salinity treatments were established by

Ertan Yildirim; Metin Turan; Ismail Guvenc

2008-01-01

19

Effects of calcium and aluminum chloride additions on foliar and throughfall chemistry in sugar maples  

Microsoft Academic Search

Calcium availability for sugar maple stands at the Hubbard Brook Experimental Forest (New Hampshire, USA) was tested by experimental addition of CaCl2 and AlCl3. Additions of 10gCam?2 represented the estimated loss from the soil exchange complex during the last 30 years due to acidic deposition. Four years of data from 12 throughfall collection sites were used to evaluate the influence

Torsten W Berger; Chris Eagar; Gene E Likens; Gerhard Stingeder

2001-01-01

20

Application of Calcium Phosphate Materials in Dentistry  

PubMed Central

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

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

2013-01-01

21

Effects of Foliar Application of Nutrients on Heat Tolerance of Creeping Bentgrass  

Microsoft Academic Search

This study was designed to investigate physiological responses of creeping bentgrass (Agrostis palustris Huds.) to foliar application of nutrients under heat stress. “Penncross” plants were exposed to two temperature regimes in growth chambers: optimum temperature control (20\\/15°C, day\\/night) and heat stress (35\\/30°C). A 10 mL solution of CaCl2 (10 mM), KH2PO4 (10 mM), NH4NO3 (124 mM), or water (untreated control) was sprayed to the

Jinmin Fu; Bingru Huang

2003-01-01

22

Foliar Boron Applications Increase the Final Number of Branches and Pods on Branches of Field-Grown Soybeans 1  

PubMed Central

Our previous work demonstrated that boron (B) supplied to soybeans (Glycine max [L.] Merrill cv `Williams 82') by a stem infusion technique increased the number of pods on branches and led to a significant yield increase. Therefore, research was continued to determine whether soil or foliar applications of B could be used to achieve the same results. Field experiments were completed with both soil and foliar applications of B. Only the foliar applications of B resulted in a significant increase in the number of pods/branch. When split foliar treatments were applied twice during flowering, the total application of 0.56 kilograms of B per hectare was the optimal treatment for increasing pods/branch. In a second field experiment in 1987, soybeans were treated weekly from flowering through podfill with six split foliar applications of aqueous H3BO3 solutions so that total applications were either 0, 1.1, or 2.24 kilograms of B per hectare. Foliar applications increased the number of branches/plant at the end of the season and significantly stimulated the formation of pods on branches, with 1.12 kilograms of B per hectare being the optimal treatment for these variables. This rate also tended to increase the number of seeds/plant and seed yield/plant. A duplicate experiment with minor modifications was conducted during the summer of 1988, and again the 1.12 kilograms of B per hectare application rate resulted in significant increases in number of branches at harvest as well as number of pods on branches. The 2.24 kilograms of B per hectare application rate also significantly increased these parameters. Foliar B applications induced increases in leaf B concentration far above the 60 micrograms per gram level that was previously accepted as the upper level of tolerance for soybeans. Since optimal branching and per plant yield parameters were achieved by plants with B leaf concentrations greater than 160 micrograms per gram, the accepted range of soybean tolerance for B must be reconsidered when B is foliarly applied. Images Figure 1

Schon, Mary K.; Blevins, Dale G.

1990-01-01

23

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

24

FOLIAR FERTILIZATION: IMPROVING THE HUMAN WELLNESS ATTRIBUTES OF MELON  

Microsoft Academic Search

Netted muskmelon (Cucumis melo L. (Reticulatus Group)) fruit quality (ascorbic acid, beta- carotene, total free sugars, and soluble solids concentration (SSC)) is directly related to plant potassium (K) concentration during fruit growth and maturation. During fruiting, soil fertilization alone is often inadequate due to poor root uptake and competitive uptake inhibition from calcium and magnesium. Foliar applications of Potassium Metalosate

G. E. Lester; J. L. Jifon

25

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

26

Sequential foliar application of vermicompost leachates improves marketable fruit yield and quality of strawberry ( Fragaria × ananassa Duch.)  

Microsoft Academic Search

The objective of the study was to determine the effect of foliar application of vermicompost leachates on growth, yield and quality of strawberry (Cv. Chandler). For this, three leachates collected from vermicomposting of cow dung (FCD), vegetable waste (FVW) and mixture of cow dung and vegetable waste in 1:2 ratio (FCVW) were used at 2mll?1 at monthly interval (total five

Rajbir Singh; R. K. Gupta; R. T. Patil; R. R. Sharma; R. Asrey; A. Kumar; K. K. Jangra

2010-01-01

27

Effects of foliar and soil insecticide applications on the collembolan community of an early set-aside arable field  

Microsoft Academic Search

Effects of foliar and soil insecticide applications on collembolan density and community structure were investigated in an early set-aside arable field. Insecticides were applied separately and in combination to the soil surface (chlorpyrifos) and vegetation (dimethoate). The treatments were established to investigate effects of above- and below-ground insects on plant succession. Starting in 1997, the insecticides were applied from April

Kerstin Endlweber; Martin Schädler; Stefan Scheu

2006-01-01

28

Growth Promotion of Yunnan Pine Early Seedlings in Response to Foliar Application of IAA and IBA  

PubMed Central

A field experiment was conducted using a 3 × 3 orthogonal regression design to explore the growth promotion of one-year-old Yunnan pine seedlings (Pinus yunnanensis Franch.) in response to foliar application of IAA (indole-3-acetic acid) at rates of 0, 200 and 400 mg·L?1 and IBA (indole-3-butyric acid) at rates of 0, 200 and 400 mg·L?1 in order to promote the growth during the seedlings’ early stage. The experiment was conducted at the Lufeng Village Forest Farm of Yiliang County in Kunming, Yunnan, China. The results showed that IAA and IBA were effective in growth promotion of Yunnan pine seedlings. The response of both growth increment and biomass accumulation to the concentration of IAA and IBA can be modeled using a bivariate surface response, and each growth index had a peak value. Growth indexes increased with the increase of the dosage of photohormones before reaching a peak value, and then decreased. The different growth indexes had various responses to the concentrations and ratio of IAA and IBA. The foliar application of IAA in combination with IBA showed the largest improvement on the biomass of the needles, followed by stems and roots. The higher ratio of IAA promoted stem diameter growth, root system development and biomass accumulation in the needles, while a higher ratio of IBA contributed to height growth and biomass accumulation in the stem. Based on the auxin effect equations on the different growth indexes and surface response, the optimum concentrations and the (IAA:IBA) ratios can be obtained. The optimum concentrations of IAA and IBA were 167 and 186, 310 and 217, 193 and 159, 191 and 221, and 206 and 186 mg·L?1, with corresponding ratios of 1:1.11, 1:0.70, 1:0.82, 1:1.15 and 1:0.90, respectively, at the maximum seedling height and collar diameter growth as well as biomass accumulation at the root, stem and needle. The above growth indexes were 22.00%, 79.80%, 48.65%, 82.20% and 107.00% higher than the control treatment.

Xu, Yulan; Zhang, Yuemin; Li, Yunfei; Li, Genqian; Liu, Daiyi; Zhao, Minchong; Cai, Nianhui

2012-01-01

29

Yield and quality of fennel (Foeniculum vulgare Mill.) in relation to basal and foliar application of nitrogen and phosphorus  

Microsoft Academic Search

A split?plot field trial was conducted to study the effect of foliar application of 0 kg\\/ha (control), 20 kg N\\/ha, 2 kg P\\/ha or 20 kg N + 2 kg P\\/ha at two basal levels, viz., 90 kg N + 40 kg P\\/ha (optimal dose) and 60 kg N + 27 kg P\\/ha (sub?optimal dose). Each group received 50 kg

M. M. A. Khan; Samiullah; S. H. Afaq; M. M. R. K. Afridi

1992-01-01

30

Foliar Symptoms of Nutrient Disorders in 'Chloris gayana'.  

National Technical Information Service (NTIS)

Foliar symptoms of nitrogen, phosphorus, potassium, calcium, magnesium, sulphur, iron, copper, zinc, manganese, and boron deficiencies and manganese and boron toxicities in Chloris gayana cv. Pioneer are described. Colour photographs of the foliar symptom...

F. W. Smith

1973-01-01

31

COMUNICAÇÃO ADUBAÇÃO COM SILÍCIO VIA FOLIAR NA ACLIMA TIZAÇÃO DE UM HÍBRIDO DE ORQUÍDEA Mineral nutrition with silicon by foliar application in orchid hybrid acclimatization  

Microsoft Academic Search

3 e contendo como substrato casca de arroz carbonizada. Foram avaliados os efeitos das concentrações (0; 0,5; 1,0; e 2,0 mg L -1 ) e fontes de silício: silicato de sódio (SS) e Supa Potássio ® (SP) via foliar e a mistura 1:1 aplicada via foliar. Após oito meses do transplantio foram avaliadas as variáveis número de folhas, comprimento da

Joyce Dória; Rodrigues Soares; Moacir Pasqual; Filipe Almendagna Rodrigues; Fabíola Villa; Janice Guedes de Carvalho

32

Effect of Foliar-Applied Humic Acid to Dry Weight and Mineral Nutrient Uptake of Maize under Calcareous Soil Conditions  

Microsoft Academic Search

Greenhouse research was conducted to determine the effects of foliar application of humic acid on dry matter and some nutrient element uptake of maize grown under calcareous soil conditions. Agricultural lime was used to obtain five calcium carbonate (CaCO3) doses (0, 5, 10 20, and 40%) and three foliar application doses of humic acid (0, 0.1, and 0.2%) sprayed at

Hakan Çelik; Ali Vahap Katkat; Bar?? Bülent A??k; Murat Ali Turan

2010-01-01

33

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

Code of Federal Regulations, 2010 CFR

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

2010-07-01

34

RESPONSE OF MAIZE TO FOLIAR VS. SOIL APPLICATION OF NITROGEN–PHOSPHORUS–POTASSIUM FERTILIZERS  

Microsoft Academic Search

Foliar fertilization is a widely used practice to correct nutritional deficiencies in plants caused by improper supply of nutrients to roots. The aim of the present study was to determine the efficiency of different forms of nitrogen–phosphorus–potassium (NPK) fertilizers applied to maize (Zea mays L.), either to the soil or to the leaves. Two sweet corn plants (CV Jubilee) were

Fan Ling; Moshe Silberbush

2002-01-01

35

Effect of sequential applications of foliar nutrients, biofertilizers and sowing dates on the incidence of corn stem borers in Egypt.  

PubMed

In this study either early sown (May 1st) or lately sown (June 2nd) corn plants were treated with Phosphorin & Rhizobactrin as biofertilizers and sprayed with six selected foliar nutrients, i.e. Polymex; Greenzit SP100, Greenzit NPK, Potasin-F, Copper sulphate and Ascorbic acid; in mono-, bi-, and/or tri-sequential applications. Such practices were conducted to show their beneficial effects compared with the chemical treatment in checking the incidence of the stem borers and hence increasing the corn yield. The obtained results could be summarized in the following chief points: (a) the lately sown biofertilized plants showed somewhat higher levels of infestation than the early planted ones., (b) in general, spraying the biofertilized corn plants in both sowing dates with the tested foliar nutrients, significantly decreased the rate of the stem borers infestation than the untreated plants of control., (c) the foliar sprays of Greenzit NPK alone, bi- or tri-sequential applications of Potasin-F, Polymex, Ascorbic acid and Copper sulphate achieved considerable success in reducing larval numbers of the borers species. For example, in case of using the bi-sequential nutrients (Polymex/Ascorbic acid) the numbers were 1.2, 1.5 and 1.2 larvae/5 plants, whereas the numbers were 1.3, 1.0 and 0.7 larvae/5 plants as a result, of the tri-sequential applications (Potasin-F/Ascorbic acid/Polymex) for the pink stem borer, Sesamia cretica, (Led.), the purple lined borer, Chilo agamemnon, (Bels.), and the European corn borer Ostrinia nubilalis (Hb.), in respect, vs. 4.8, 4.5 and 2.9 larvae/5 plants for the same stem borers, respectively, in case of the untreated corn plants. In addition, the other trisequential applications (Polymex/ascorbic acid/Copper sulphate), (Potasin-F/Copper sulphate/ascorbic acid) and (Potasin-F/Copper sulphate/Polymex) reduced the stem borers infestation; (d) from the view point of the interaction effects of sowing dates and the tested foliar nutrients, it was found that the tri-sequential sprayings (Potasin-F/Copper sulphate/Polymex) and/or (Potasin-F/Copper sulphate/Ascorbic acid) have lowered the rate of the stem borers infestation to 3.3 and 3.3 and 5.7 and 4.3 larvae/5 plants for the tri-applications in the 1st and 2nd sowing dates, respectively. Such reductions in the levels of infestation led to an increase in the grain yield up to 6.9 and 7.2 and 5.4 and 5.8 ton/fed, for the early and lately sown corn plants, in respect, and (e) All the foliar nutrients, with no exception, proved to be efficient in managing the stem borers infestation as compared with the insecticide treatment using Polytrin. Although the chemical application had lowered the level of infestation to 2.3 and 5.7 larvae/5 plants in the 1st and 2nd sowing dates as compared with 9.7 and 14.7 larvae/5 untreated plants for the same sowing dates, lesser grain yield of 5.6 and 4.4 ton/fed. was obtained in the first and second dates of planting, successively, in comparison to the grain yield resulted from the tri-applications of Potasin-F/Copper sulphate with either Polymex or Ascorbic acid. The abovementioned results assured the profitable effects of using foliar nutrients as well as the biofertilizers for attaining healthy corn plants, which would be capable of tolerating the injury inflicted by the studied stem borers and compensating for the harmful effects of insects infestation, so high grain yields could be obtained than those of the untreated and/or the insecticide treated plants. PMID:12696416

Mesbah, H A; Mourad, A K; el-Nimr, Hanyiat M; el-Kady, Magda B; Haroun, Nagah S

2002-01-01

36

Effects of Calcium-Containing Foliar Sprays Combined with Titanium and Algae Extract on Plum Fruit Quality  

Microsoft Academic Search

An experiment was performed in which soluble calcium (Ca) was sprayed on plum trees in combinations with two bioactivators containing (Ti)-ascorbate and\\/or marine algae extract to study the effects on the commercial quality of fruits, with special attention paid to any increase in their resistance to postharvest handling damage. All the treatments containing titanium (Ti) increased tree development and fruit

Carlos Alcaraz-Lopez; Maria Botía; Carlos F. Alcaraz; Fernando Riquelme

2004-01-01

37

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

38

Foliar Damage, Ion Content, and Mortality Rate of Five Common Roadside Tree Species Treated with Soil Applications of Magnesium Chloride  

Microsoft Academic Search

Sensitivity to magnesium chloride (MgCl2) was assessed on five common roadside tree species by maintaining soil concentrations at 0-, 400-, 800-, or 1,600-ppm chloride\\u000a via MgCl2 solution over four growing seasons. Evaluations of growth, leaf retention, foliar damage, and ion concentrations were conducted.\\u000a Water potentials were measured on two species. Foliar chloride and magnesium concentrations were positively correlated with\\u000a foliar

Betsy A. Goodrich; William R. Jacobi

39

Nanostructured calcium phosphates for biomedical applications: novel synthesis and characterization  

Microsoft Academic Search

Materials play a key role in several biomedical applications, and it is imperative that both the materials and biological aspects are clearly understood for attaining a successful biological outcome. This paper illustrates our approach to implement calcium phosphates as gene delivery agents. Calcium phosphates (CaP) belong to the family of biocompatible apatites and there are several CaP phases, the most

Prashant N. Kumta; Charles Sfeir; Dong-Hyun Lee; Dana Olton; Daiwon Choi

2005-01-01

40

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

Code of Federal Regulations, 2010 CFR

...true Applicability; description of the calcium hydroxide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory....

2010-07-01

41

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

Code of Federal Regulations, 2012 CFR

...false Applicability; description of the calcium carbide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Carbide Production Subcategory § 415.30 Applicability; description of the calcium carbide production subcategory....

2012-07-01

42

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

Code of Federal Regulations, 2010 CFR

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

2009-07-01

43

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

Code of Federal Regulations, 2010 CFR

...false Applicability; description of the calcium hydroxide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory....

2009-07-01

44

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

Code of Federal Regulations, 2012 CFR

...false Applicability; description of the calcium carbonate production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory....

2012-07-01

45

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

Code of Federal Regulations, 2013 CFR

... Applicability; description of the calcium subcategory. 461.20 Section 461...MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart...

2013-07-01

46

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

Code of Federal Regulations, 2010 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2009-07-01

47

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

Code of Federal Regulations, 2011 CFR

... Applicability; description of the calcium subcategory. 461.20 Section 461...MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart...

2011-07-01

48

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

Code of Federal Regulations, 2010 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2010-07-01

49

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

Code of Federal Regulations, 2010 CFR

...true Applicability; description of the calcium oxide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium oxide production subcategory....

2010-07-01

50

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

Code of Federal Regulations, 2012 CFR

...Applicability; description of the other calcium carbide furnaces subcategory. 424...MANUFACTURING POINT SOURCE CATEGORY Other Calcium Carbide Furnaces Subcategory § 424.50 Applicability; description of the other calcium carbide furnaces subcategory....

2012-07-01

51

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

Code of Federal Regulations, 2012 CFR

...false Applicability; description of the calcium oxide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Oxide Production Subcategory § 415.50 Applicability; description of the calcium oxide production subcategory....

2012-07-01

52

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

Code of Federal Regulations, 2010 CFR

...false Applicability; description of the calcium carbonate production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory....

2009-07-01

53

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

Code of Federal Regulations, 2010 CFR

... Applicability; description of the calcium subcategory. 461.20 Section 461...MANUFACTURING POINT SOURCE CATEGORY Calcium Subcategory § 461.20 Applicability; description of the calcium subcategory. This subpart...

2010-07-01

54

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

Code of Federal Regulations, 2012 CFR

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

2012-07-01

55

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

Code of Federal Regulations, 2010 CFR

...true Applicability; description of the calcium carbonate production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Carbonate Production Subcategory § 415.300 Applicability; description of the calcium carbonate production subcategory....

2010-07-01

56

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

Code of Federal Regulations, 2012 CFR

...false Applicability; description of the calcium hydroxide production subcategory. 415...CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Calcium Hydroxide Production Subcategory § 415.310 Applicability; description of the calcium hydroxide production subcategory....

2012-07-01

57

Growth, Yield and Nutrient Uptake of Wheat (Triticum aestivum L.) in relation to Foliar and Soil Application of Urea  

Microsoft Academic Search

We conducted a field experiment to investigate the effect of soil and foliar spray of urea on the growth, yield, nutrient uptake and grain protein content of wheat (cv. 'Mehran-89'). The thrice replicated treatments included T1: 150 kg N ha-1 as urea by broadcasting, T2: ½ T1 + 1% foliar spray of urea (FSU), T3: ½ T1 + 2% FSU,

AKBAR MAITLO; AHMAD NAQI SHAH; HAJRA KHAN

58

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

59

Improving yield, quality, and shelf life of Thompson seedless grapevine by preharvest foliar applications  

Microsoft Academic Search

Ten-year-old Thompson seedless grape vines were sprayed during 2009 and 2010 growing seasons with putrescine (Put), gibberellic acid (GA3), ascorbic acid (AA), ethephon (Eth), salicylic acid (SA), cytofex (CPPU) and calcium chloride (CaCl2) at two stages of berry development; pea stage (4–5mm fruitlet diameter, ?30–35 days after fruit set) and veraison stage (when approximately 20% of the berries on 50%

H. A. Marzouk; H. A. Kassem

2011-01-01

60

Effects of foliar application with compost tea and filtrate biogas slurry liquid on yield and fruit quality of washington navel orange (Citrus sinenesis Osbeck) trees.  

PubMed

Sixteen-year-old navel orange trees at a private orchard located in Kafer El-Sheikh Governorate, Egypt, were used in this study. Compost tea (CT) and filtrate biogas slurry liquid (FLB) were applied at two different concentrations (50% and 100%); control trees were sprayed with water Trees treated with CT at 100% were the highest in yield, fruit weight, and vitamin C, whereas the highest percentage of fruit set, fruit number and soluble solid content (SSC), lowest fruit drop, and highest reducing and total sugars were in trees treated with 100% FLB. Concentrations at 50% for both foliar application (CT and FLB) improved yield and fruit characteristics than control treatment. Generally, using a foliar application of compost tea and filtrate biogas slurry liquid at (100%) treatments as food nutrients could be recommended to improve the yield and fruit quality of navel orange fruits under the current study conditions. PMID:22866578

Omar, Alaa El-din K; Belal, Elsayed B; El-Abd, Abd El-Naiem A

2012-07-01

61

ENHANCEMENT OF GROWTH AND NORMAL GROWTH PARAMETERS BY FOLIAR APPLICATION OF POTASSIUM AND PHOSPHORUS IN TOMATO CULTIVARS GROWN AT HIGH (NaCl) SALINITY  

Microsoft Academic Search

Three tomato (Lycopersicon esculentum) cvs., Rio Grande, Monika F1, and Marylin F1, were grown hydroponically in a controlled temperature (CT) room for 6 weeks to investigate the effectiveness of foliar application of supplementary potassium (K) and phosphorus (P) to the leaves of plants grown at high NaCl concentration (60 mM). Supplementary 5 mM K and P as KH2PO4 was supplied

Cengiz Kaya; Halil Kirnak; David Higgs

2001-01-01

62

The Effect of Spray Application Rate and Airflow Rate on Foliar Deposition in a Hedgerow Vineyard  

Microsoft Academic Search

Two experiments were performed in a hedgerow vineyard, in June (after end of blossom) and July (full vegetation development) to assess the influence of spray application rate and air output on the spray distribution from an axial-fan sprayer. Measurements were performed by fluorometry, using Brilliant Sulpha Flavine as a tracer.Increasing spray application rate and air output both led to higher

Gianfranco Pergher; Rino Gubiani

1995-01-01

63

Boron foliar application on sunflower (Helianthus annuus L.) associated with herbicides  

Microsoft Academic Search

SUMMARY The present work was undertaken to evaluate volunteer corn control through the application of graminicides singly or combined with boron (B) sources as well as to assess the sunflower (Helianthus annuus L.) response to the application of this micronutrient. Experiments were arranged in a split-plot design with randomized complete blocks and five replications. The treatments applied were haloxyfop-methyl 0.048

A. M. Brighenti; C. Castro

2008-01-01

64

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

PubMed Central

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

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

2012-01-01

65

Physiological Response of Soybean (Glycine max) to Foliar Application of Methanol Under Different Soil Moistures  

Microsoft Academic Search

Problem statement: Many cultivated area are situated in arid zone, whe re crop photosynthesis and productivity has limited by drou ght. Thus any treatment, such as methanol, that improve plant water relation and reduce stress impa cts, could be benefit. Approach: In order to investigate effects of methanol application on some physiological properties of soybean under low water stress, a

Farzad Paknejad; Mojtaba Mirakhori; Majid Jami Al-Ahmadi; Mohammad Reza Tookalo; Ali Reza Pazoki; Parisa Nazeri

2009-01-01

66

Calcium  

MedlinePLUS

... Office of Dietary Supplements Dietary Supplement Fact Sheet: Calcium QuickFacts Datos en español Health Professional Other Resources Create PDF What is calcium and what does it do? Calcium is a ...

67

Metabolization of Elemental Sulfur in Wheat Leaves Consecutive to Its Foliar Application 1  

PubMed Central

The qualitative and quantitative aspects of elemental sulfur metabolization in wheat leaves and its effect upon photosynthetic metabolism were studied through the application of micronized sulfur upon the third leaf. Energy-dispersive x-ray analysis combined with scanning electron microscopy emphasized the existence of a sulfur peak associated with a strong potassium peak in the spectra of different tissue regions for treated leaves only, supplying an original evidence of sulfur uptake. Experiments with35S-labeled micronized sulfur showed that about 2% of the labeled S was absorbed and metabolized into cystine, methionine, glutathione, and sulfate. The close correlation between the excess of oxygen uptake and oxygen needs for sulfur oxidation in conjunction with the absence of hydrogen sulfide released by treated leaves support direct and fast oxidation of sulfur into sulfate according to a pathway still unclear but independent of photosynthetic CO2 metabolism in treated leaf. The mechanisms involved in the primary metabolism of element sulfur in wheat therefore appear to be different from those in fungi. Images Fig. 2

Legris-Delaporte, Stephanie; Ferron, Francoise; Landry, Jacques; Costes, Claude

1987-01-01

68

Influence of surfactants on potassium uptake and yield response of cotton to foliar potassium nitrate  

Microsoft Academic Search

Foliar potassium (K) applications are intended to supplement soil K uptake, and thereby, increase cotton (Gossypium hirsutum L.) yields. Considerable research has been conducted to evaluate yield response to foliar K, but research evaluating surfactant effects on foliar uptake has been limited. Research was initiated in West Tennessee in 1991 to evaluate effects of foliar applied potassium nitrate (KNO3) with

D. D. Howard; C. O. Gwathmey

1995-01-01

69

Calcium nutrition affects cold hardiness, yield, and fruit disorders of apple and pear trees  

Microsoft Academic Search

Foliar sprays of calcium chloride (CaCl2) and to a lesser extent, soil applications of calcium nitrate [Ca(NO3)2] fertilizer, increased calcium (Ca) concentrations in leaves and fruit of apple, (Malus domestica) and pear (Pyrus communis L.) trees. For most years, CaCl2 sprays or Ca(NO3)2 fertilizer increased cold hardiness of ‘Anjou’ pear trees, and reduced the incidence of fruit disorders (alfalfa greening

J. Thomas Raese

1996-01-01

70

Effect of Soil Fertilizer, Foliar Fertilizer, and Growth Regulator Application on Milk Thistle Development, Seed Yield, and Silymarin Content  

Microsoft Academic Search

An important consideration for milk thistle (Silybum marianum L.) cultivation is regulating development to lengthen the reproductive stage and increase seed yield with high silymarin content. The treatment of milk thistle with foliar fertilizers and growth regulators—thidiazuron (Dropp), 2,3,5?triiodobenzoic acid (Tiba), mepiquat chloride (Pix), and prohexadione?Ca (Regalis)—resulted in an increase in the proportion of mature flower heads. Highest seed yield

Maria Geneva; Grigor Zehirov; Ira Stancheva; Lubomir Iliev; Georgi Georgiev

2007-01-01

71

Correlation of epiphyllous bud differentiation with foliar senescence in crassulacean succulent Kalanchoe pinnata as revealed by thidiazuron and ethrel application.  

PubMed

Leaves of Kalanchoe pinnata have crenate margins with each notch bearing a dormant bud competent to develop into a healthy plantlet. Leaf detachment is a common signal for inducing two contrastingly different leaf-based processes, i.e. epiphyllous bud development into plantlet and foliar senescence. To investigate differentiation of bud and its correlation, if any, with foliar senescence, thidiazuron (TDZ), having cytokinin activity and ethrel (ETH), an ethylene releasing compound, were employed. The experimental system was comprised of marginal leaf discs, each harbouring an epiphyllous bud. Most of the growth characteristics of plantlet developing from the epiphyllous bud were significantly inhibited by TDZ but promoted by ETH. The two regulators modulated senescence in a manner different for leaf discs and plantlet leaves. Thus, TDZ caused a complete retention whereas ETH a complete loss of chlorophyll in the leaf discs. In contrast, the former resulted in a complete depletion of chlorophyll from the plantlet leaves producing an albino effect, while the latter reduced it by 50% only. In combined dispensation of the two regulators, the effect of TDZ was expressed in majority of responses studied. The results presented in this investigation clearly show that the foliar processes of epiphyllous bud differentiation and senescence are interlinked as TDZ that delayed senescence inhibited epiphyllous bud differentiation and ETH that hastened senescence promoted it. A working hypothesis to interpret responsiveness of the disc-bud composite on lines of a source-sink duo, has been proposed. PMID:16616582

Jaiswal, Sarita; Sawhney, Sudhir

2005-09-12

72

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

Code of Federal Regulations, 2012 CFR

...Applicability; description of the covered calcium carbide furnaces with wet air pollution...MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution...Applicability; description of the covered calcium carbide furnaces with wet air...

2012-07-01

73

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

Code of Federal Regulations, 2010 CFR

...Applicability; description of the covered calcium carbide furnaces with wet air pollution...MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution...Applicability; description of the covered calcium carbide furnaces with wet air...

2010-07-01

74

Calcium  

MedlinePLUS

... strong bones and teeth. Why Do I Need Calcium? Bones grow rapidly during adolescence, and teens need ... and canned salmon with bones. Back Continue Working Calcium Into Your Diet Looking for ways to up ...

75

Applications of Calcium and its Supplement derived from Marine Organisms  

Microsoft Academic Search

Calcium, being an essential mineral with many important and diversified functions, plays an important role in the health and well being of the human. Marine organisms serve as an alternate source for calcium. Calcium has to be solubilized in the body in order to have the maximum benefits. The increased solubility of calcium from diet contributes to calcium absorption and

Se-Kwon Kim; Y. Dominic Ravichandran; Chang-Suk Kong

2012-01-01

76

Application of the 45 Ca tracer method for determination of calcification rates in calcareous algae: Effect of calcium exchange and differential saturation of algal calcium pools  

Microsoft Academic Search

Calcium exchange and differential saturation of algal calcium pools complicate the application of the 45Ca tracer method for the determination of net deposition rates of calcium in calcareous algae. The kinetics of 45Ca uptake is critically reevaluated, and it is shown that incorporation occurs in two stages. A fast stage, saturating the exchangeable calcium pools; and a slow stage, giving

L. Böhm

1978-01-01

77

Estimation of leaf wetness duration requirements of foliar fungal pathogens with uncertain data-an application to Mycosphaerella nawae.  

PubMed

Wetness of the host surface is a critical environmental factor for the development of foliar fungal diseases, but it is difficult to estimate the wetness durations required by pathogens for infection when only few experimental data are available. In this paper, we propose a method to estimate wetness duration requirements of foliar fungal pathogens when precise experimental data are not available. The proposed method is based on approximate Bayesian computation. It only requires lower and upper bounds of wetness duration requirements for one or fewer temperatures. We describe the method, show how to apply it to an infection model, and then present a case study on Mycosphaerella nawae, the causal agent of circular leaf spot of persimmon. In this example, the parameters of a simple infection model were estimated using experimental data found in the literature for the pathogen, and the model was applied to assess the risk in a Spanish area recently affected by the disease. The results showed that the probability of successful infection was higher than 0.5 for 32% of the on-site wetness durations recorded in the affected area. Results obtained with simulated data showed that our method was able to improve the estimation of wetness duration requirement. Given the flexibility of the proposed method, we expect it to become adopted for assessing the risk of introduction of exotic fungal plant pathogens. PMID:21864085

Makowski, D; Bancal, R; Vicent, A

2011-11-01

78

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

NASA Astrophysics Data System (ADS)

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

Krausher, Jennifer Lynn

79

Effects of foliar boron application on seed composition, cell wall boron, and seed ?15N and ?13C isotopes in water-stressed soybean plants  

PubMed Central

Limited information is available on the effects of foliar boron (B) application on soybean seed composition. The objective of this research was to investigate the effects of foliar B on seed composition (protein, oil, fatty acids, and sugars). Our hypothesis was that since B is involved in nitrogen and carbon metabolism, it may impact seed composition. A repeated greenhouse experiment was conducted where half of the soybean plants was exposed to water stress (WS) and the other half was well-watered. Foliar boron (FB) in the form of boric acid was applied twice at a rate of 1.1 kg ha?1. The first application was during flowering stage, and the second application was during seed-fill stage. Treatments were water stressed plants with no FB (WS–B); water stressed plants with FB (WS+B); watered plants without FB (W–B), and watered plants with FB (W+B). The treatment W–B was used as a control. Comparing with WS–B plants, B concentration was the highest in leaves and seed of W+B plants (84% increase in leaves and 73% in seed). Seeds of W+B plants had higher protein (11% increase), oleic acid (27% increase), sucrose (up to 40% increase), glucose, and fructose comparing with W–B. However, seed stachyose concentrations increased by 43% in WS–B plants seed compared with W–B plants. Cell wall (structural) B concentration in leaves was higher in all plants under water stress, especially in WS–B plants where the percentage of cell wall B reached up to 90%. Water stress changed seed ?15N and ?13C values in both B applied and non-B applied plants, indicating possible effects on nitrogen and carbon metabolism. This research demonstrated that FB increased B accumulation in leaves and seed, and altered seed composition of well-watered and water stressed plants, indicating a possible involvement of B in seed protein, and oleic and linolenic fatty acids. Further research is needed to explain mechanisms of B involvement in seed protein and fatty acids.

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

2013-01-01

80

Foliar application of Zn at flowering stage improves plant's performance, yield and yield attributes of black gram.  

PubMed

Black gram plants subjected to varying levels of Zn supply (0.01 to 10 microM Zn) showed optimum growth and dry matter yield in plants receiving 1 microM Zn. The dry matter yield of plants decreased in plants receiving 0.01 and 0.1 microM Zn (deficient) and excess levels of Zn (2 and 10 microM Zn). The plants grown with Zn deficient supply showed delayed flowering, premature bud abscission, reduced size of anthers, pollen producing capacity, pollen viability and stigma receptivity resulting in poor pod formation and seed yield. Providing Zn as a foliar spray at pre-flowering stage minimized the severity of Zn deficiency on reproductive structure development and enhanced the seed nutritional status by enhancing seed Zn density, seed carbohydrate (sugar and starch content) and storage proteins (albumins, globulins, glutenins, and prolamines). PMID:23898554

Pandey, Nalini; Gupta, Bhavana; Pathak, Girish Chandra

2013-07-01

81

Supplemental Foliar Potassium Applications during Muskmelon Fruit Development Can Improve Fruit Quality, Ascorbic Acid, and Beta-carotene Contents  

Microsoft Academic Search

Muskmelon (Cucumis melo L. (Reticulatus Group)) fruit sugar content is directly related to potassium (K)- mediated phloem transport of sucrose into the fruit. However, during fruit growth and maturation, soil fertilization alone is often inadequate (due to poor root uptake and competitive uptake inhibition from calcium and magnesium) to satisfy the numerous K-dependent processes, such as photosynthesis, phloem transport, and

Gene E. Lester; John L. Jifon; Gordon Rogers

82

Calcium hydroxide dressings using different preparation and application modes: density and dissolution by simulated tissue pressure  

Microsoft Academic Search

Peters CI, Koka RS, Highsmith S, Peters OA. Calcium hydroxide dressings using different preparation and application modes: density and dissolution by simulated tissue pressure. International Endodontic Journal, 38, 889-895, 2005. Aim To study the effect of different apical shapes in prepared simulated root canals on the application of a commercially prepared calcium hydroxide paste by a syringe or lentulo spiral.

C. I. Peters; R. S. Koka; S. Highsmith; O. A. Peters

2005-01-01

83

FOLIAR NUTRIENT REFERENCE LEVELS OBTAINED IN HYDROPONIC CULTURES AS PRELIMINARY NORMS FOR DRIS TO FERTIGATE CONIFERS  

Microsoft Academic Search

Preliminary norms for foliar tissue were developed for Cupressus glabra grown on a sand culture for use in the diagnosis and recommendation integrated system (DRIS). These norms were generated from macronutrients nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) of high-quality plants growing in hydroponics cultures in controlled conditions. The values were those of foliar tissues from

Enrique Eymar; Carlos Cadahía; Africa Sánchez

2001-01-01

84

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

SciTech Connect

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

Idso, S.B.; Garcia, R.L.; Kimball, B.A. [Water Conservation Lab., Phoenix, AR (United States); Idso, K.E.; Hoober, J.K. [Arizona State Univ., Tempe, AR (United States)

1995-01-01

85

Amorphous calcium phosphate and its application in dentistry  

Microsoft Academic Search

Amorphous Calcium Phosphate (ACP) is an essential mineral phase formed in mineralized tissues and the first commercial product\\u000a as artificial hydroxyapatite. ACP is unique among all forms of calcium phosphates in that it lacks long-range, periodic atomic\\u000a scale order of crystalline calcium phosphates. The X-ray diffraction pattern is broad and diffuse with a maximum at 25 degree\\u000a 2 theta, and

Jie Zhao; Yu Liu; Wei-bin Sun; Hai Zhang

2011-01-01

86

Biphasic calcium phosphate bioceramics: preparation, properties and applications  

Microsoft Academic Search

Biphasic calcium phosphate (BCP) bioceramics belong to a group of bone substitute biomaterials that consist of an intimate mixture of hydroxyapatite (HA), Ca10(PO4)6(OH)2, and beta-tricalcium phosphate (ß-TCP), Ca3(PO4)2, of varying HA\\/ß-TCP ratios. BCP is obtained when a synthetic or biologic calcium-deficient apatite is sintered at temperatures at and above 700 °C. Calcium deficiency depends on the method of preparation (precipitation,

R. Z. LeGeros; S. Lin; R. Rohanizadeh; D. Mijares; J. P. LeGeros

2003-01-01

87

Soil and leaf nutrient interactions following application of calcium silicate slag to sugarcane  

Microsoft Academic Search

In certain areas of the Everglades Agricultural Area, plant and ratoon sugarcane (Saccharum L.) yields are increased by application of Si from calcium silicate slag. The greatest yield responses are obtained in the plant crop the first year after application of slag and when plant uptake of Si is increased. Magnesium deficiencies have been reported after slag application. The objective

D. L. Anderson

1991-01-01

88

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

PubMed Central

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

Mejia-Teniente, Laura; de Dalia Duran-Flores, Flor; Chapa-Oliver, Angela Maria; Torres-Pacheco, Irineo; Cruz-Hernandez, Andres; Gonzalez-Chavira, Mario M.; Ocampo-Velazquez, Rosalia V.; Guevara-Gonzalez, Ramon G.

2013-01-01

89

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

PubMed

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

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

2013-05-15

90

Effect of Application of Acidified Porous Hydrate Calcium Silicate and Porous Hydrated Calcium Silicate on the Growth of Rice Plants (Oryza sativa L.)  

Microsoft Academic Search

The effect of the application of acidified porous hydrate calcium silicate (APS) in nursery bed soil and porous hydrate calcium silicate (PS) in paddy fields on the growth of rice plants (Oryza sativa L. cv. Hitomebore) was examined in 2002 and 2003. The results revealed the following: 1) Shoot dry weight of rice seedlings increased by APS treatment in nursery

Hironori Heinai; Masahiko Saigusa; Kazuo Yoshida; Hitoshi Okazaki

2005-01-01

91

[Calcium antagonists: current and future applications based on new evidence. Neuroprotective effect of calcium antagonists].  

PubMed

Voltage-dependent Ca(2+) channels have been divided into at least 5 types (L-, N-, T-, P-, and Q-type). L/N-type Ca(2+) channel blocker cilnidipine could reduce the size of cerebral infarction in the rat focal brain ischemia. L-type Ca(2+) channel blocker amlodipine reduced cerebral edema and inhibit neuronal cell death. N-type Ca(2+) channel blocker omega-conotoxin reduce the size of cerebral infarction and inhibit delayed neuronal cell death in hippocampal CA1 area. It is suggested that calcium antagonist has neuroprotective effect. PMID:20048438

Ito, Yasuo; Araki, Nobuo

2010-01-01

92

Foliar Iron Fertilization: A Critical Review  

Microsoft Academic Search

Application of foliar iron (Fe) sprays is a common means of correcting Fe deficiency of agricultural crops. However, variable plant responses to iron sprays, ranging from no effect to defoliation, have often been described in the Fe-fertilization literature. Knowledge is still limited concerning the mechanisms of penetration of a leaf-applied, Fe-containing solution and the role of Fe in the leaf.

Victoria Fernández; Georg Ebert

2005-01-01

93

Formation of silver incorporated calcium phosphate film for medical applications  

Microsoft Academic Search

Calcium phosphate coating layers were formed by electron beam evaporation of hydroxyapatite as an evaporant with and without simultaneous Ar ion bombardments. The Ca\\/P ratio of film, which determined the biological properties, was controlled by ion beam current. Without ion beam bombardments, the film had the low Ca\\/P ratio of 1.30, however, the ratio increased to 2.02 by bombarding of

In-Seop Lee; Chung-Nam Whang; Kyung-Sik Oh; Jong-Chul Park; Kwon-Yong Lee; Gun-Hwan Lee; Sung-Min Chung; Xiao-Dan Sun

2006-01-01

94

Properties and applications of calcium hydroxide in endodontics and dental traumatology.  

PubMed

Calcium hydroxide has been included within several materials and antimicrobial formulations that are used in a number of treatment modalities in endodontics. These include, inter-appointment intracanal medicaments, pulp-capping agents and root canal sealers. Calcium hydroxide formulations are also used during treatment of root perforations, root fractures and root resorption and have a role in dental traumatology, for example, following tooth avulsion and luxation injuries. The purpose of this paper is to review the properties and clinical applications of calcium hydroxide in endodontics and dental traumatology including its antibacterial activity, antifungal activity, effect on bacterial biofilms, the synergism between calcium hydroxide and other agents, its effects on the properties of dentine, the diffusion of hydroxyl ions through dentine and its toxicity. Pure calcium hydroxide paste has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. Its main actions are achieved through the ionic dissociation of Ca(2+) and OH(-) ions and their effect on vital tissues, the induction of hard-tissue deposition and the antibacterial properties. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. It has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also an effective anti-endotoxin agent. However, its effect on microbial biofilms is controversial. PMID:21535021

Mohammadi, Z; Dummer, P M H

2011-05-02

95

Calcium Deficient Hydroxyapatite for Medical Application Prepared by Hydrothermal Method  

NASA Astrophysics Data System (ADS)

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

Ioku, Koji; Kamitakahara, Masanobu; Ikeda, Tohru

2010-11-01

96

The influence of foliar and soil fertilization of humic acid on yield and quality of pepper  

Microsoft Academic Search

Humic acid (HA) is the result of organic matter decomposition and is beneficial to plant growth and development. The objective of the study was to find the influence of foliar and soil HA application on fruit quality and yield of organically grown pepper. Pepper plants were treated with soil and foliar HA applications at various concentrations (0 ml\\/l, 10 ml\\/l,

Yasar Karakurt; Husnu Unlu; Halime Unlu; Huseyin Padem

2009-01-01

97

The composite of hydroxyapatite and calcium sulphate: a review of preclinical evaluation and clinical applications.  

PubMed

Recent publications have shown that the combination of ?-calcium sulfate hemihydrate, the densest form of hydrates and hydroxyapatite (HA) particles gives good clinical outcome in various applications. It has large potential as bone substitute since the material transforms to bone throughout the entire volume and not only by creeping substitution, from the surface toward the inside. Release of important proteins for osteogenesis has been observed around implanted material and is speculated to be due to fast dissolution of the calcium sulfate phase in combination with the osteoconductive and bioactive nature of HA. In diabetic foot infection, the osteoconductive HA/calcium sulfate material has been successfully used loaded with antibiotics and since it is injectable, the application is minimally invasive, easy and precise. It is a bone substitute for the future. PMID:24053255

Nilsson, Malin; Zheng, Ming H; Tägil, Magnus

2013-09-01

98

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

NASA Astrophysics Data System (ADS)

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

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

2005-12-01

99

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

NASA Astrophysics Data System (ADS)

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

Greish, Yaser Elhanafy

100

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

Microsoft Academic Search

Organically doped calcium phosphosilicate nanoparticles (CPSNPs) were developed and characterized, driven by the need for non-toxic vectors for drug delivery and fluorescence biological imaging applications. In particular, advancement in drug delivery for the chemotherapeutic treatment of cancers is required to increase drug efficacy and improve patient quality of life. Additionally, brighter and more photostable fluorophores are needed to meet demands

Thomas T. Morgan

2010-01-01

101

Rare-earth doped low silica calcium aluminosilicate glasses for near and mid infrared applications  

Microsoft Academic Search

The combination of properties such as chemical durability, transformation temperature, thermo-mechanical properties, refractory properties, phonon energy of about 800 cm?1 and infrared transparency up to 6 ?m, recommend low silica (<7 wt%) calcium aluminosilicate glasses as hosts for laser applications. We have been investigating the physical properties of these glasses prepared by melting under vacuum conditions. This preparation procedure ensured

M. L. Baesso; A. C. Bento; L. C. M. Miranda; D. F. de Souza; J. A. Sampaio; L. A. O. Nunes

2000-01-01

102

Cations in olivine, Part 1: Calcium partitioning and calcium-magnesium distribution between olivines and coexisting melts, with petrologic applications  

Microsoft Academic Search

As part of a study of kinetic and equilibrium aspects of magmatic olivines (Jurewicz 1986; Jurewicz and Watson 1988), calcium distribution and partitioning sys- tematics have been experimentally determined for olivine\\/ melt pairs under a wide variety of temperatures, pressures and oxygen fugacities. The calcium content of an equilibrated olivine depends upon (1) the concentration of calcium in the melt

Amy J. G. Jurewicz; E. Bruce Watson

1988-01-01

103

[Calcium antagonists: current and future applications based on new evidence. Calcium channel blockers and autonomic nervous system].  

PubMed

Calcium channel blockers are widely used for the treatment of hypertension. Although they are effective for their strong vasodilator action, there are concerns regarding related baroreflex-mediated activation of sympathetic nervous system. However, long-acting calcium channel blockers, such as amlodipine, are now known safe for the treatment of hypertension. Furthermore, the new type of calcium channel blockers, such as cilnidipine with N-type calcium channel blocking action, or azelnidipine that has sympatho-inhibitory action with anti-oxidant effect, provide a new insight for the future use of calcium channel blockers. PMID:20048431

Hirooka, Yoshitaka; Sunagawa, Kenji

2010-01-01

104

Premixed calcium silicate cement for endodontic applications: injectability, setting time and radiopacity.  

PubMed

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

Persson, Cecilia; Engqvist, Håkan

105

A thermodynamic equilibrium model for calcium salt urolithiasis: clinical application.  

PubMed

It is proposed that urine is better modelled as a true equilibrium rather than in a supersaturated/metastable state and that the free citrate3- ion plays a major role in maintaining dispersion of the solid particles (reduced agglomeration). Published urinary chemistries, in conjunction with the computer programme SEQUIL, have been used to formulate a novel risk index for calcium stone formation independent of the traditional clinical classification of the stone former. Applying the risk index to three consecutive 24-hour urine samples of 39 untreated Ca stone formers showed that 35 (90%) patients produced at least one abnormal urine. Traditional single urinary parameter assessment, Ca/Cr, oxalate/Cr or citrate/Cr ratios, showed that only 17, 14, and 18% of the patients, respectively, had an abnormality, while taking all three together 24 (70%) had some abnormality and thus 30% were 'idiopathic' stone formers. Treatment regimens have been devised using the computer programme to return an abnormal urine to the normal according to the proposed risk index. In most urines two or more factors had to be changed simultaneously. Clinically there has been only one recurrence in 36 months, whereas before they had 4.4/3 years. PMID:9208285

Ashby, R; Györy, A Z

106

Uptake of Hydrophilic Solutes Through Plant Leaves: Current State of Knowledge and Perspectives of Foliar Fertilization  

Microsoft Academic Search

Foliar fertilization is an agricultural practice of increasing importance in practical terms. Since nutrient sprays are mostly applied as water solutions, the focus of the article was placed on the penetration of ionic, polar solutes through the leaf surface, although the mechanisms of cuticular penetration of lipophilics are also taken into consideration. In theory, application of foliar nutrient sprays may

V. Fernández; T. Eichert

2009-01-01

107

Development and application of a liquid chromatography-mass spectrometry method to evaluate the glyphosate and aminomethylphosphonic acid dissipation in maize plants after foliar treatment.  

PubMed

A simple and fast method has been developed and validated to measure glyphosate (GLYP) and aminomethylphosphonic acid (AMPA), which were previously derivatized with 9-fluorenylmethylchloroformate (FMOC-Cl), in maize plants using liquid chromatography (LC) coupled to fluorescence (FLD) and electrospray ionization mass spectrometry (ESI-MS) detection. The method has shown to be consistent, reliable, precise, and efficient. Moreover, the limits of detection (LOD) and quantification (LOQ) reached with the proposed method for GLYP and AMPA are lower than the established maximum residue levels (MRLs). The validated method was applied to quantify GLYP and AMPA in genetically modified (GM) maize foliar treated with the herbicide. It has been found that the GLYP dissipation was mainly due to the progressive dilution effect after herbicide treatment. Finally, it was also observed that the GLYP residue dissipation trend in maize shoot (leaves and stem) tissue determined by LC-ESI-MS matched that determined by liquid scintillation. PMID:22480367

Bernal, José; Martin, María T; Soto, María E; Nozal, María J; Marotti, Ilaria; Dinelli, Giovanni; Bernal, José L

2012-04-13

108

Watermelon foliar fungicide timing trial  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

109

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

NASA Astrophysics Data System (ADS)

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

Bapat, Parimal V.

110

Effect of GA3 and 2,4-D foliar application on the anatomy of date palm (Phoenix dactylifera L.) seedling leaf.  

PubMed

Two concentrations (10-5M and 10-3M) of both GA3 and 2,4-D were used as foliar spray to evaluate the response of date palm (Phoenix dactylifera L.) cv. Khedri seedlings. They affected some of the anatomical characteristics of the first leaf emerging after the beginning of the spray. The high concentration of GA3 increased the size of the midrib and its vascular bundle numbers. Both low and high concentrations of 2,4-D inhibited the formation of the midrib. 2,4-D in both low and high concentrations decreased the number of vessels in both protoxylem and metaxylem and also decreased their diameters, where as GA3 in low and high concentrations have less effect on the number of vessels and its diameters. GA3 in high concentration increased the number of vascular bundles in 1mm long of the leaf blade, while 2,4-D in low and high concentrations decreased their numbers. 10-3M of 2,4-D increased the size and layers of special hypodermal cells. PMID:23961229

Doaigey, Abdullah R; Al-Whaibi, M H; Siddiqui, M H; Al Sahli, A A; El-Zaidy, M E

2012-12-20

111

Effect of GA3 and 2,4-D foliar application on the anatomy of date palm (Phoenix dactylifera L.) seedling leaf  

PubMed Central

Two concentrations (10-5M and 10-3M) of both GA3 and 2,4-D were used as foliar spray to evaluate the response of date palm (Phoenix dactylifera L.) cv. Khedri seedlings. They affected some of the anatomical characteristics of the first leaf emerging after the beginning of the spray. The high concentration of GA3 increased the size of the midrib and its vascular bundle numbers. Both low and high concentrations of 2,4-D inhibited the formation of the midrib. 2,4-D in both low and high concentrations decreased the number of vessels in both protoxylem and metaxylem and also decreased their diameters, where as GA3 in low and high concentrations have less effect on the number of vessels and its diameters. GA3 in high concentration increased the number of vascular bundles in 1mm long of the leaf blade, while 2,4-D in low and high concentrations decreased their numbers. 10-3M of 2,4-D increased the size and layers of special hypodermal cells.

Doaigey, Abdullah R.; Al-Whaibi, M.H.; Siddiqui, M.H.; Al Sahli, A.A.; El-Zaidy, M.E.

2012-01-01

112

Effect of Pre-Harvest Foliar Application of Citric Acid and Malic Acid on Chlorophyll Content and Post-Harvest Vase Life of Lilium cv. Brunello  

PubMed Central

Citric acid is a regular ingredient in many vase solution formulations but pre-harvest use of citric acid is a novel method in vase life extension of cut flowers, which is reported on tuberose earlier. In order to verify previous result, and check for possible substitution of citric acid by malic acid, the current research was designed. Citric acid (0, 0.075, 0.15% w/v) and malic acid (0, 0.075, 0.15% w/v) were used in a factorial design with three replications. Foliar sprays were applied two times during growth period of Lilium plants. The results point out that 0.15% citric acid alone had increased vase life from 11.8 in control treatment to 14?days (??

Darandeh, Nafiseh; Hadavi, Ebrahim

2012-01-01

113

Influence of calcium ion deposition on apatite-inducing ability of porous titanium for biomedical applications.  

PubMed

In the present study, the influence of calcium ion deposition on the apatite-inducing ability of porous titanium (Ti) was investigated in a modified simulated body fluid (m-SBF). Calcium hydroxide (Ca(OH)(2)) solutions with five degrees of saturation were used to hydrothermally deposit Ca ions on porous Ti with a porosity of 80%. Apatite-inducing ability of the Ca-ion-deposited porous Ti was evaluated by soaking them in m-SBF for up to 14 days. Scanning electron microscopy (SEM) and X-ray diffractometry (XRD) confirmed that a thin layer of calcium titanate (CaTiO(3))/calcium oxide (CaO) mixture with a nanostructured porous network was produced on porous Ti substrates after hydrothermal treatment at 200 degrees C for 8 h. X-ray photoelectron spectroscopy results demonstrated that the content of the Ca ions deposited on Ti and the thickness of the CaTiO(3)/CaO layer increased with increasing saturation degree of the Ca(OH)(2) solution. The thickest (over 10 nm) CaTiO(3)/CaO layer with the highest Ca content was achieved on the Ti treated in an oversaturated Ca(OH)(2) solution (0.2 M). SEM, XRD, transmission electron microscopy and Fourier transformed infrared spectroscopy analysis indicated that the porous Ti samples deposited with the highest content of Ca ions exhibited the best apatite-inducing ability, producing a dense and complete carbonated apatite coating after a 14 day soaking in m-SBF. The present study illustrated the validity of using Ca ion deposition as a pre-treatment to endow desirable apatite-inducing ability of porous Ti for bone tissue engineering applications. PMID:19223253

Chen, Xiao-Bo; Li, Yun-Cang; Du Plessis, Johan; Hodgson, Peter D; Wen, Cui'e

2009-01-22

114

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

Microsoft Academic Search

Calcium sulfite hemihydrate (CaSOâ · 0.5HâO), a common byproduct of coal-fired utilities, is fairly insoluble and can decompose to release toxic SOâ under highly acidic soil conditions; however, it can also oxidize to form gypsum. The objective of this study was to examine the effects of application rate and soil pH on the oxidation of calcium sulfite under laboratory conditions.

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

2007-01-01

115

Foliar and soil fertilization of humic acid affect productivity and quality of tomato  

Microsoft Academic Search

The objective of the study was to determine the effect of foliar and soil fertilization with humic acid (HA) on quality, growth and yield of tomato under greenhouse conditions in 2004 and 2005. Tomato plants were treated with soil and foliar HA applications at different concentrations (0 ml\\/l, 10 ml\\/l and 20 ml\\/l). Three weeks after planting HA was sprayed

Ertan Yildirim

2007-01-01

116

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

USGS Publications Warehouse

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

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

2005-01-01

117

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

PubMed Central

Calcium phosphate (CaP) polymorphs are nontoxic, biocompatible and hold promise in applications ranging from hard tissue regeneration to drug delivery and vaccine design. Yet, simple and robust routes for the synthesis of protein-coated CaP nanoparticles in the sub-100 nm size range remain elusive. Here, we used cell surface display to identify disulfide-constrained CaP binding peptides that, when inserted within the active site loop of E. coli Thioredoxin 1 (TrxA), readily and reproducibly drive the production of nanoparticles that are 50–70 nm in hydrodynamic diameter and consist of an approximately 25 nm amorphous calcium phosphate (ACP) core stabilized by the protein shell. Like bone and enamel proteins implicated in biological apatite formation, peptides supporting nanoparticle production were acidic. They also required presentation in a loop for high affinity ACP binding since elimination of the disulfide bridge caused a nearly 3-fold increase in hydrodynamic diameters. When compared to a commercial aluminum phosphate adjuvant, the small core-shell assemblies led to a 3-fold increase in mice anti-TrxA titers three weeks post-injection, suggesting that they might be useful vehicles for adjuvanted antigen delivery to dendritic cells.

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

2012-01-01

118

Application of Atomic Absorption Spectro- photometry in the Determination of Calcium in Serum  

Microsoft Academic Search

Atomic absorption spectrophotometry (AAS) was applied to the determination of serum calcium. A specialdiluent was developedto abolishthe effect of absorption depressors.This made possiblemeasurement of calcium in directly diluted serum sampleswithout prior removalof any serum constituents. Values obtained by AAS on calcium oxalate precipitates from serum were identical with those found by the direct dilution technique. THE RECENT appearance of good

Alfred Zettner; David Seligson

119

Growth of calcium phosphates on magnesium substrates for corrosion control in biomedical applications via immersion techniques.  

PubMed

Magnesium (Mg) has been suggested as a revolutionary biodegradable replacement for current permanent metals used in orthopedic applications. Current investigations concentrate on the control of the corrosion rate to match bone healing. Calcium phosphate coatings have been a recent focus of these investigations through various coating protocols. Within this investigation, an in situ crystallization technique was utilized as an inexpensive and relatively simple method to produce a brushite and monetite coating on pure Mg. Coatings were characterized using energy dispersive spectroscopy, glancing angle X-ray diffraction and field emission scanning electron microscopy. Corrosion protection properties of the coatings were assessed in physiological buffers, Earles balanced salt solution, minimum essential media, and minimum essential media containing serum albumin, over a 4-week period. Using this novel coating protocol, our findings indicate brushite and monetite coated Mg to have significant corrosive protective effects when compared with its uncoated counterpart whilst maintaining high coating substrate adhesion, homogeneity, and reproducibility. PMID:23090758

Shadanbaz, Shaylin; Walker, Jemimah; Staiger, Mark P; Dias, George J; Pietak, Alexis

2012-10-22

120

Foliar application of distillery-spent wash as a liquid fertilizer for betterment of growth of Sorghum vulgare and Cajanus cajan  

Microsoft Academic Search

The distillery spent wash contained all necessary elements and biofertilizer microbes (Rhizobia, Azospirilla, Azotobacter, and phosphobacteria) to support the growth of plants. Application of the spent wash, as it is without dilution, did not\\u000a cause deformities and derangement of plant metabolism. The successful use of distillery spent wash as a liquid fertilizer\\u000a for augmenting crop productivity in C3 and C4

R. Suresh Babu; V. C. Saralabai; K. S. Muralidharan; M. Vlvekanandam

1996-01-01

121

Pre-harvest foliar application of Prohexadione-Ca and gibberellins modify canopy source-sink relations and improve quality and shelf-life of ‘Bing’ sweet cherry  

Microsoft Academic Search

This research evaluated the potential of gibberellins (GA), and Prohexadione-Ca (PCa) to affect sweet cherry (Prunus avium) fruit size and quality. The results demonstrate the ability of ostensibly counter-acting plant growth regulators to significantly\\u000a improve sweet cherry cv ‘Bing’ fruit size, fruit quality and postharvest characteristics compared to the current commercial\\u000a application of GA3 alone. In 2008, we found that

Caixi Zhang; Matthew Whiting

122

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

PubMed

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

Liu, Wei-Ting; Li, Kung-Cheh

2011-01-01

123

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

NASA Astrophysics Data System (ADS)

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

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

1981-11-01

124

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

SciTech Connect

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

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

1981-11-20

125

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

PubMed Central

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

2012-01-01

126

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

PubMed

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

Pandey, Nalini; Gupta, Bhavana

2012-09-01

127

Retardation of Phosphate Release from Freshwater Benthic Sediments by Application of Ocher Pellets with Calcium Nitrate  

Microsoft Academic Search

This article presents an in situ treatment method for retardation of phosphate release from freshwater benthic sediments. The method is based on the addition of ocher pellets into benthic sediments. The pellets consist of ocher and calcium nitrate (OCN pellet). The OCN pellet slowly releases calcium and nitrate, together with ocher, into the sediment–water interface, where all three components play

Yu-Mee Na; Seok S. Park

2004-01-01

128

Application of ion-selective microelectrodes to the detection of calcium release during bone resorption  

Microsoft Academic Search

In this work we apply calcium ion-selective liquid membrane microelectrodes to the investigation of the release of ionised calcium in real-time from bovine cortical bone slices in the presence of osteoclasts. The osteoclast is the cell responsible for the resorption (dissolution) of bone and excess bone resorption is implicated in diseases such as osteoporosis. Pretreatment of the bone slice with

C. E. M Berger; B. R Horrocks; H. K Datta

1999-01-01

129

Maleic acid based scale inhibitors for calcium sulfate scale inhibition in high temperature application  

Microsoft Academic Search

In anhydrite rich reservoir rock, calcium sulfate is one of the dominant scale components which unlike carbonate scale are not easily removable by acid or dissolver treatment. To inhibit calcium sulfate scale formation in high temperature producing brine water systems, maleic acid–acrylic acid and maleic acid–acrylamide copolymers of appropriate molecular weight were synthesized and characterized and inhibition efficiency of the

B. Senthilmurugan; B. Ghosh; S. S. Kundu; M. Haroun; B. Kameshwari

2010-01-01

130

Pharmacological modulators of voltage-gated calcium channels and their therapeutical application  

Microsoft Academic Search

Calcium channels (CCs) play an important role in the transduction of action potential to the cytosol. An influx of Ca2+ is essential for muscle contraction, neurotransmitter, and hormonal release. Level of cytosolic Ca2+ controls activities of many enzymes and regulatory proteins. Voltage-gated calcium channels (VGCCs) serve as sensors for membrane depolarization. Blood pressure reduction is due to relaxation of actomyosine

Andrei A. Kochegarov

2003-01-01

131

WALL TILING FIXATIVES FOR APPLICATIONS ON CALCIUM-SILICATE BRICK WALLS  

Microsoft Academic Search

The performance of different types of fixatives is evaluated, with the aims of establishing the most suitable fixatives for internal wall tiling on calcium silicate brick walls. Test panels of wall tiles were fixed to rendered and unrendered calcium silicate brick walls with different fixatives. Strains in the tiles were measured with strain gauges. Those at the face of the

T. E. Uher

1986-01-01

132

Foliar washoff of pesticides by rainfall  

SciTech Connect

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

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

1986-05-01

133

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

PubMed

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

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

2012-02-15

134

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

SciTech Connect

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

Mortvedt, J.J.

1986-01-01

135

PARTITIONING THE RELATIVE INFLUENCE OF SOIL N, MYCORRHIZAE, AND FOLIAR N UPTAKE ON FOLIAR delta15N PATTERNS: CAN WE DETECT FOLIAR UPTAKE OF REACTIVE N?  

Microsoft Academic Search

Vegetation is an important sink for atmospheric reactive N in N-limited systems and may be capable of incorporating reactive N compounds directly into leaves through the foliar uptake pathway. A proxy for atmospheric reactive N entering vegetation would be useful to estimate the impact of direct foliar N uptake on plant metabolism. Natural abundance foliar N isotopic composition (delta15N) is

D. Vallano; J. P. Sparks

2009-01-01

136

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

PubMed

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

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

1996-05-01

137

Amorphous calcium carbonate in form of spherical nanosized particles and its application as fillers for polymers  

Microsoft Academic Search

The synthesis of amorphous calcium carbonate (ACC) via a liquid precursor to give spherical particles with monodisperse distribution of diameters in the range of 0.4–1.2?m has been optimized to the level to obtain multigram yields per batch. The synthesis was achieved by precipitation of ACC from a strongly alkaline solution of calcium chloride (CaCl2) at ambient temperature using the hydrolysis

K. Gorna; M. Hund; M. Vu?ak; F. Gröhn; G. Wegner

2008-01-01

138

Microstructure of the system calcium aluminate cement-silica fume: application in waste immobilization  

Microsoft Academic Search

The immobilization of wastes in cement suggests that cement compositions can be tailored in terms of pH, Eh and internal chemistry so as to maximize immobilization potential. This work presents some studies concerning the micro structure of calcium aluminate cement (CAC), and silica fume-calcium aluminate cement (SF-CAC) systems, and their resistance to the leaching by natural waters, with a view

A. Hidalgo; S. Petit; J. L. García; C. Alonso; C. Andrade

2007-01-01

139

Amorphous calcium silicate hydrate/block copolymer hybrid nanoparticles: synthesis and application as drug carriers.  

PubMed

Amorphous calcium silicate hydrate (CSH)/block copolymer monomethoxy(polyethyleneglycol)-block-poly(lactide-co-glycolide) (mPEG-PLGA) (CSHP) hybrid nanoparticles have been prepared in aqueous solution via a facile coprecipitation route at room temperature. The block copolymer mPEG-PLGA micelles in aqueous solution serve as the templates, and the CSH links to the micelles by hydrogen bonding between the silanol groups and the hydrophilic mPEG segments. The obtained core/shell hybrid nanoparticles can be transformed to solid hybrid nanoparticles by washing with water. The drug ibuprofen (IBU) loading capacity of the CSHP hybrid nanoparticles is ultrahigh (~1.9 g drug per g carrier), and the IBU loading efficiency can reach as high as ~100%. The drug release of loaded IBU in the CSHP hybrid nanoparticles has been investigated in simulated body fluid (SBF). The loaded IBU drug in CSHP hybrid nanoparticles can release in SBF for a long period of time (about 300 h), during which the CSHP nanocarrier is completely transformed to hydroxyapatite, exhibiting a good bioactivity. The IBU drug release profile can be interpreted by the Higuchi model. The loading capacity for the anticancer drug docetaxel (DTX) in the CSHP hybrid nanoparticles is about 82 mg g(-1). More importantly, the release of the loaded DTX in phosphate buffer saline (PBS) at pH 5.5 is obviously faster than that at pH 7.4, which is promising for the application in cancer therapy. Human gastric carcinoma (SGC-7901) cells can be effectively killed in the presence of the DTX-loaded CSHP hybrid nanoparticles at appropriate concentrations. Thus, the CSHP hybrid nanoparticles are promising nanocarriers in drug delivery. Furthermore, the hemoglobin (Hb) loading capacity of CSHP hybrid nanoparticles can achieve an utrahigh value of 995 mg g(-1), suggesting that the as-prepared CSHP hybrid nanoparticles are excellent protein adsorbents. PMID:23511873

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

2013-05-21

140

IMPROVEMENT OF MILK THISTLE (SILYBUM MARIANUM L.) SEED YIELD AND QUALITY WITH FOLIAR FERTILIZATION AND GROWTH EFFECTOR MD 148\\/II  

Microsoft Academic Search

Summary. The effects of foliar or soil fertilization and MD 48\\/II (3-methylphenylamide 5-tert-butylpyrazine-2-carboxylic acid) on the vegetative and reproductive growth, some physiological parameters, seed yield and silymarin content of field grown milk thistle (Silybum marianum L. Gaertn.) plants were studied. Foliar fertilizer AgroleafR was applied at different plant developmental stages, with different proportions of N, P, K. Combined application of

M. Geneva; I. Stancheva; M. Sichanov; M. Boychinova; G. Georgiev; M. Dolezal

141

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

SciTech Connect

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

Lee, Y.B.; Bigham, J.M.; Dick, W.A.; Jones, E.S.; Ramsier, C. [Ohio State University, Columbus, OH (United States). School of Environmental & Natural Resources

2007-01-15

142

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

Code of Federal Regulations, 2010 CFR

...calcium carbide furnaces with wet air pollution control devices subcategory...Calcium Carbide Furnaces With Wet Air Pollution Control Devices Subcategory ...calcium carbide furnaces with wet air pollution control devices...

2009-07-01

143

Phosphorous acid residues in apples after foliar fertilization: Results of field trials  

Microsoft Academic Search

The levels of phosphorous acid residues in apples after foliar fertilization with P fertilizers and after treatment with a phosphonate fungicide (Fosetyl-Al) were determined and compared. Two field trials and a glasshouse experiment, using different genotypes and plants of different age, were carried out and monitored over a three-year period. Phosphorous acid residues were found in apples after application of

E Malusà; L Tosi

2005-01-01

144

Sweet basil essential oil composition: relationship between cultivar, foliar feeding with nitrogen and oil content  

Microsoft Academic Search

The aromatic and curative properties of sweet basil (Ocimum basilicum L.) are mainly related to the contents and chemical composition of essential oil. This substance may undergo quantitative and qualitative changes under the influence of various factors, among others, the agrotechnical and environmental ones. The subject of the foregoing studies was determining the effect of foliar nitrogen application (0.5% urea

Renata Nurzy?ska-Wierdak

2012-01-01

145

Effect of coir pith based cyanobacterial basal and foliar biofertilizer on Basella rubra L  

Microsoft Academic Search

The growth promoting effect of basal and foliar application of coir pith based cyanobacterial biofertilizer on Basella rubra L. was determined by analyzing the morphological and biochemical parameters of the control and test plants after treatment. Compared to control plants test plants showed better height, stem circumference, number of branches, number of leaves and number of flowers. Biochemical analysis of

P. ABRAHAM CHRISTOPHER; V. VISWAJITH; S. PRABHA; K. SUNDHAR; P. MALLIGA

2007-01-01

146

Calcium Calculator  

MedlinePLUS

... Fun Stuff Fun Stuff Best for Bones Food Calcium Calculator How much calcium do you get every day? Remember, you need ... Deal with Vitamin D List of Foods with Calcium & Vitamin D Calcium Calculator Fooling Around with Food ...

147

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

PubMed

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

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

2010-04-29

148

Calcium alginate entrapped preparation of ?-galactosidase: its stability and application in hydrolysis of soymilk galactooligosaccharides.  

PubMed

Thermostable ?-galactosidase from Aspergillus terreus (GR) was insolubilized using concanavalin A obtained from jack bean extract and in order to maintain the integrity of complex in the presence of its substrate or products, this complex was crosslinked with glutaraldehyde. Soluble ?-galactosidase entrapped in calcium alginate retained 82% of enzyme activity whereas, Con A-?-galactosidase complex entrapped in calcium alginate and crosslinked Con A-?-galactosidase complex entrapped calcium alginate retained 74 and 61% activity, respectively. A fluidized bed reactor was constructed for continuous hydrolysis of galactooligosaccharides in soymilk using crosslinked Con A-?-galactosidase complex entrapped calcium alginate. Optimum conditions such as pH (5.0) and temperature (65°C) were the same for all immobilized enzyme preparations and soluble enzyme. Crosslinked Con A-?-galactosidase entrapped complex exhibited enhanced thermostability and showed 62% of activity (38%) after 360 min at 65°C. Entrapped crosslinked Con A-?-galactosidase complex preparation was superior in the continuous hydrolysis of oligosaccharides in soymilk by batch processes compared to the other entrapped preparations. The entrapped crosslinked concanavalin A-?-galactosidase complex retained 95% activity after eight cycles of use. PMID:21181428

Shankar, S K; Kumar, S K Praveen; Mulimani, V H

2010-12-23

149

The mechanism of action of calcium antagonists relative to their clinical applications  

PubMed Central

1 As a class of therapeutic agents calcium antagonists have attracted increasing attention in recent years. Their major indications have been in the treatment of ischaemic myocardial syndromes, certain cardiac arrhythmias, hypertension, obstructive cardiomyopathies, and a number of lesser clinical disorders in which their role is less clearly defined. With the widening spectrum of therapeutic utility and an increasing plethora of newer agents under development, it is of importance to relate the overall pharmacodynamics of individual agents to their clinical effects. 2 Calcium antagonists have a variable specificity for cardiac and peripheral activity. Based on such activity, it is useful to construct a classification of these compounds, new and old, into four categories. (i) Type I agents, typified by verapamil and its congeners (tiapamil and gallopamil) and diltiazem, prolong AV nodal conduction and refractoriness with little effect on ventricular or atrial refractory period. These actions account for their direct antiarrhythmic properties. (ii) Type II agents include nifedipine and other dihydropyridines. In vivo, these agents are devoid of electrophysiologic effects in usual doses. They are potent peripheral vasodilators with some selectivity of action for different vascular beds; their overall haemodynamic effects are dominated by this peripheral vasodilatation and reflex augmentation of sympathetic reflexes. (iii) Type III agents include flunarizine and cinnarizine (piperazine derivatives), which, in vitro and in vivo, are potent dilators of peripheral vessels, with no corresponding calcium-blocking actions in the heart. (iv) Type IV agents are agents with a broader pharmacologic profile (perhexiline, lidoflazine and bepridil); they block calcium fluxes in the heart, in the peripheral vessels, or both. They may inhibit the fast channel in the heart and have other electrophysiologic actions. 3 A clear understanding of the varied pharmacologic properties of the different classes of calcium antagonists is likely to provide a rational basis for the use of these agents in clinical therapeutics. ImagesFigure 5

Singh, B. N.

1986-01-01

150

Calcium polysulfide soil stabilization method and compositions  

US Patent & Trademark Office Database

Soil is stabilized and strengthened by application of solutions of calcium polysulfides. Compositions useful for soil stabilization comprise aqueous solutions of calcium polysulfide or aqueous mixtures of calcium polysulfides and dispersed organic polymers. Emulsifiers provide soil penetration.

Ferm; Richard L. (Lafayette, CA)

1981-01-06

151

Calcium Oscillations  

PubMed Central

Calcium signaling results from a complex interplay between activation and inactivation of intracellular and extracellular calcium permeable channels. This complexity is obvious from the pattern of calcium signals observed with modest, physiological concentrations of calcium-mobilizing agonists, which typically present as sequential regenerative discharges of stored calcium, a process referred to as calcium oscillations. In this review, we discuss recent advances in understanding the underlying mechanism of calcium oscillations through the power of mathematical modeling. We also summarize recent findings on the role of calcium entry through store-operated channels in sustaining calcium oscillations and in the mechanism by which calcium oscillations couple to downstream effectors.

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

2011-01-01

152

Influence of the calcium content on the coal fly ash features in some innovative applications  

Microsoft Academic Search

Despite a low chemical reactivity, recent trends in the innovative uses of coal fly ash based on the chemical properties have been successful. Lots of fly ash showing sharply alkaline reaction (water pH rising to 11–12 upon contact) usually are high-calcium (>3–4%), most of which is present as CaO. These lots are suitable to be used as remotion agents of

Paola Catalfamo; Sebastiana Di Pasquale; Francesco Corigliano; Letterio Mavilia

1997-01-01

153

Preparation and characterisation of calcium-phosphate porous microspheres with a uniform size for biomedical applications.  

PubMed

In the present work, a novel route for the preparation of porous ceramic microspheres is described. Two ceramic powders, calcium-titanium-phosphate (CTP) and hydroxyapatite (HAp), were mixed with a sodium alginate solution that enabled the preparation of spherical particles, using the droplet extrusion method combined with ionotropic gelation in the presence of Ca(2+). The spherical particles were subsequently sintered, to burn-off the polymer and obtain calcium-phosphate microspheres with a uniform size and an interconnected porous network. CTP microspheres with diameters ranging from 513 +/- 24 microm to 792 +/- 35 microm and with pores of approximately 40 microm were obtained. HAp microspheres presented diameters of 429 +/- 46 microm and 632 +/- 40 microm and pores of ca. 2 microm. Depending on the formulations tested, the structure of both calcium phosphates may become altered during the sintering process, suggesting that the ratio between the ceramic phase and the polymer solution is a critical parameter. Porous microspheres prepared using the described methodology are promising candidates as bone defect fillers and scaffolds for bone tissue regeneration. PMID:16688586

Ribeiro, C C; Barrias, C C; Barbosa, M A

2006-05-01

154

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

PubMed Central

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

2011-01-01

155

Quantifying foliar uptake of gaseous nitrogen dioxide using enriched foliar delta15N values.  

PubMed

The magnitude and impact of gaseous nitrogen dioxide (NO(2)) directly entering the leaves were investigated using foliar nitrogen isotopic composition (delta(15)N) values in tomato (Lycopersicon esculentum) and tobacco (Nicotiana tabacum). Using a hydroponics-fumigation system, (15)NO(2) (20 and 40 ppb) was supplied to shoot systems and (50 and 500 microM) was supplied to root systems. Morphological, stable isotope and nitrate reductase activity (NRA) analyses were used to quantify foliar NO(2) uptake and to examine whether realistic concentrations of NO(2) influenced plant metabolism. Nicotiana tabacum and L. esculentum incorporated 15 and 11%, respectively, of (15)NO(2)-N into total biomass via foliar uptake under low supply. On a mass basis, N. tabacum and L. esculentum incorporated 3.3 +/- 0.9 and 3.1 +/- 0.8 mg of (15)NO(2)-N into biomass, respectively, regardless of availability. There were no strong effects on biomass accumulation or allocation, leaf delta(13)C values, or leaf or root NRA in response to NO(2) exposure. Foliar NO(2 )uptake may contribute a significant proportion of N to plant metabolism under N-limited conditions, does not strongly influence growth at 40 ppb, and may be traced using foliar delta(15)N values. PMID:18069953

Vallano, Dena M; Sparks, Jed P

2007-12-07

156

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

SciTech Connect

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

Selig, Jiri [Lamar University; Lin, Sidney [Lamar University; Lin, Hua-Tay [ORNL; Johnson, D Ray [ORNL; Wang, Hsin [ORNL

2011-01-01

157

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

PubMed

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

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

2004-09-22

158

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

PubMed

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

Uskokovi?, Vuk; Uskokovi?, Dragan P

2011-01-01

159

Application of impedance spectroscopy to evaluate the effect of different setting accelerators on the developed microstructures of calcium phosphate cements.  

PubMed

The main goal of the present study was to evaluate the effect of different setting accelerator agents on the developed microstructures of calcium phosphate cements (CPCs) by employing the impedance spectroscopy (IS) technique. Six compositions of CPCs were prepared from mixtures of commercial dicalcium phosphate anhydrous (DCPA) and synthesized tetracalcium phosphate (TTCP) as the solid phases. Two TTCP/DCPA molar ratios (1/1 and 1/2) and three liquid phases (aqueous solutions of Na(2)HPO(4), tartaric acid (TA) and oxalic acid (OA), 5% volume fraction) were employed. Initial (I) and final (F) setting times of the cement pastes were determined with Gillmore needles (ASTM standard C266-99). The hardened samples were characterized by X-ray powder diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and apparent density measurements. The IS technique was employed as a non-destructive tool to obtain information related to porosity, tortuosity and homogeneity of the cement microstructures. The formulation prepared from a TTCP/DCPA equimolar mixture and OA as the liquid phase presented the shortest I and F (12 and 20 min, respectively) in comparison to the other studied systems. XRD analyses revealed the formation of low-crystallinity hydroxyapatite (HA) (as the main phase) as well as the presence of little amounts of unreacted DCPA and TTCP after 24 h hardening in 100% relative humidity. This was related to the proposed mechanisms of dissolution of the reactants. The bands observed by FTIR allowed identifying the presence of calcium tartrate and calcium oxalate in the samples prepared from TA and OA, in addition to the characteristic bands of HA. High degree of entanglement of the formed crystals was observed by SEM in samples containing OA. SEM images were also correlated to the apparent densities of the hardened cements. Changes in porosity, tortuosity and microstructural homogeneity were determined in all samples, from IS results, when the TTCP/DCPA ratio was changed from 1/1 to 1/2. The cement formulated from an equimolar mixture of TTCP/DCPA and OA as the liquid phase presented setting times, degree of conversion to low-crystallinity HA and microstructural features suitable to be used as potential bone cement in clinical applications. The IS technique was shown to be a very sensitive and non-destructive tool to relate the paste composition to the developed microstructures. This approach could be very useful to develop calcium phosphate bone cements for specific clinical demands. PMID:19347256

Romeo, H E; Bueno, P R; Fanovich, M A

2009-04-04

160

The application of calcium phosphate precipitation chemistry to phosphorus recovery: the influence of organic ligands.  

PubMed

This paper describes current knowledge of phosphate precipitation chemistry in the context of phosphorus recovery from wastewaters, and presents experimental results on the effect of organic species, as key potential inhibitors, to the precipitation of calcium phosphate. The supersaturation required for precipitation at 25 degrees C, pH 7, 0.1 M ionic strength and near-stoichiometric (for hydroxylapatite) calcium to phosphate molar ratio was determined under spontaneous precipitation conditions. The experiments were carried out in air. The phase precipitating at the critical concentration was allowed to grow under constant supersaturation. The influence of organic ligands on the precipitation was investigated using two small molecular weight organic ligands, acetate and citrate, present at a concentration of 10(-3) M. The precipitate was studied using X-ray diffraction and scanning electron microscopy. Good reproducibility of the experiments, which were carried out in triplicate, was observed. The study assessed the supersaturation necessary for spontaneous precipitation of hydroxylapatite to be 10.93, calculated using a solubility constant of log K= -57.74. The required supersaturation was not affected by the presence of acetate. However, citrate was found to increase the supersaturation required for precipitation to 11.73. It is likely that this increase is due to binding of citrate on the active growth sites of newly formed nuclei, thereby inhibiting precipitation. All experiments showed formation of a single phase: micro-crystalline hydroxylapatite. PMID:11804354

van der Houwen, J A; Vaisami-Jones, E

2001-11-01

161

Synthesis and characterization of porous nanocrystalline biphasic calcium phosphate for bio applications  

NASA Astrophysics Data System (ADS)

The nano crystalline biphasic calcium phosphates of hydroxyapatite (HAp)/?-tricalcium phosphate (?-TCp) in the ratio 80:20 and 72:28 with interconnected porosity have successfully been prepared by co-precipitation method using mixed catanionic surfactants as template. The sample was calcinated at various temperatures for 8 h. The samples were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, Field emission scanning electron microscopy (FESEM) and thermal analyser. The samples calcinated at 750°C and 850°C show 75% and 89% of crystallinity respectively. Usually to obtain the biphasic calcium phosphates, either the medium will be set as acidic by altering the pH or the Ca/P ratio can be set below the value of 1.5. However this experiment was neither conducted with low Ca/P ratio (<=1.5) nor at low pH (<=7) to obtain the mixed phase. The combination of surfactants and calcination temperature controls the HAp/?-TCp ratio.

Shanthi, P. Michael S. L.; Ashok, M.; Balasubramanian, T.

2012-10-01

162

New processing approaches in calcium phosphate cements and their applications in regenerative medicine.  

PubMed

The key feature of calcium phosphate cements (CPCs) lies in the setting reaction triggered by mixing one or more solid calcium phosphate salts with an aqueous solution. Upon mixture, the reaction takes place through a dissolution-precipitation process which is macroscopically observed by a gradual hardening of the cement paste. The precipitation of hydroxyapatite nanocrystals at body or room temperature, and the fact that those materials can be used as self-setting pastes, have for many years been the most attractive features of CPCs. However, the need to develop materials able to sustain bone tissue ingrowth and be capable of delivering drugs and bioactive molecules, together with the continuous requirement from surgeons to develop more easily handling cements, has pushed the development of new processing routes that can accommodate all these requirements, taking advantage of the possibility of manipulating the self-setting CPC paste. It is the goal of this paper to provide a brief overview of the new processing developments in the area of CPCs and to identify the most significant achievements. PMID:20123046

Ginebra, M P; Espanol, M; Montufar, E B; Perez, R A; Mestres, G

2010-02-01

163

Theory and applications of geometric scaling of localized calcium release events  

PubMed Central

Geometric measures of localized calcium release (LCR) events have been used to understand their biophysical basis. We found power law scaling between three such metrics—maximum amplitude (MA), mass above half-maximum amplitude (MHM), and area at half-maximum amplitude (AHM). In an effort to understand this scaling a minimal analytic model was employed to simulate LCR events recorded by confocal line scan. The distribution of logMHM as a function of logAHM, pMHM(pAHM), was dependent on model parameters such as channel open time, current size, line scan offset, and apparent diffusion coefficient. The distribution of log[MHM/AHM] as a function of logMA, p[MHM/AHM](pMA), was invariant, reflecting the gross geometry of the LCR event. The findings of the model were applied to real LCR line scan data from rabbit portal vein myocytes, rat cerebral artery myocytes, and guinea pig fundus knurled cells. pMHM(pAHM) could be used to distinguish two populations of LCR events in portal vein, even at the scale of “calcium noise,” and to calculate the relative current of the two. The relative current was 2. pMHM(pAHM) could also be used to study pharmacological effects. The pMHM(pAHM) distribution of knurled cell LCR events was markedly contracted by ryanodine, suggesting a reduction in channel open time. The p[MHM/AHM](pMA) distributions were invariant across all cell types and were consistent with the model, underlying the common physical basis of their geometry. The geometric scaling of LCR events demonstrated here may help with their mechanistic characterization.

Harhun, Maksym I.; Huizinga, Jan D.

2010-01-01

164

Fibrin Gel-Immobilized Primary Osteoblasts in Calcium Phosphate Bone Cement: In vivo Evaluation with Regard to Application as Injectable Biological Bone Substitute  

Microsoft Academic Search

Osteogenic injectable bone substitutes may be useful for many applications. We developed a novel injectable bone substitute based on osteoblast-fibrin glue suspension and calcium phosphate bone cement (BC). Human osteoblasts were isolated from trabecular bone samples and cultured under standard conditions. Osteoblasts were suspended in fibrinogen solution (FS). BC was cured with thrombin solution. 8 × 4 mm injectable bone

U. Kneser; A. Voogd; J. Ohnolz; O. Buettner; L. Stangenberg; Y. H. Zhang; G. B. Stark; D. J. Schaefer

2005-01-01

165

Application of lime and calcium hypochlorite in the dephenolisation and discolouration of olive mill wastewater  

Microsoft Academic Search

The application of hypochlorite for the removal of soluble COD, phenolic and polyphenolic like compounds, and other organic compounds responsible for the olive mill wastewater (OOWW) colour has been experimentally studied. After the OOWW filtration on a sand column, the effluent was subjected to a fast liming under optimal conditions. Lime application reduced polyphenols, COD and SS contents to half

F. Boukhoubza; A. Jail; F. Korchi; L. Loukili Idrissi; H. Hannache; J. C. Duarte; L. Hassani; A. Nejmeddine

2009-01-01

166

Calcium phosphate sol-gel-derived coatings on titanium-aluminum-vanadium substrate for biomedical applications  

NASA Astrophysics Data System (ADS)

Osseointegration of implants to host bone is a necessary requirement for dental and orthopaedic implants. The rate and quality of osseointegration were enhanced through the use of calcium phosphate (Ca-P) films on metallic substrates. The present study investigates the characteristics of Ca-P films applied using sol-gel dip coating methods to sintered porous-surfaced implants. Ca-P films have been formed using Inorganic Route and Organic Route processes. It has been shown that both approaches resulted in the formation of carbonated hydroxyapatite but with different Ca/P ratios as well as different surface textures and film structures, the Inorganic Route-formed film being more porous at its outermost surface, and having a more irregular topography. An interfacial reaction product (calcium titanium oxide) was detected for the Inorganic Route-formed coatings while this interfacial phase was not detectable in the Organic Route-formed coatings. The interface tensile and shear adhesion strength properties of Ca-P films have been evaluated using an improved direct pull-off testing (ASTM C633) and a substrate straining method, respectively. For both Ca-P films, the adhesive tensile strength was higher than the failure stress of ˜38 MPa occurring between the Ca-P films and the glue or in the glue. A shear lag approach revealed a shear strength of 347 +/- 64MPa and 280 +/- 28MPa for the Inorganic Route and the Organic Route Ca-P films, respectively. In vivo animal model studies have been performed to compare the effect on early bone formation of sintered porous-surfaced implants that had been modified through the addition of Ca-P film. In Group I study (i.e. Inorganic Route-formed Ca-P-coated implants vs. non-coated implants), it has been found that the Inorganic Route-formed Ca-P film significantly enhances the early rate of bone ingrowth for sintered porous-surfaced implants. However, in Group II study (i.e. Organic Route-formed Ca-P-coated implants vs. non-coated implants), significant improvement was not observed for the Organic Route-formed Ca-P film. It is speculated that the slightly different surface topography and film density between the two Ca-P films result in a different amounts of protein adsorption on the implant surface at the early stage, which further affects the following processes leading to osseointegration.

Gan, Lu

167

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

168

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

Federal Register 2010, 2011, 2012, 2013

...of commercial nurseries to control Eleutherodactylus frogs. The applicant proposes the...of commercial nurseries to control Eleutherodactylus frogs. Information in accordance...necessary to control the tropical frogs, Eleutherodactylus coqui and E. planirostris,...

2010-05-21

169

Piezoelectric and Dielectric Properties of Calcium and Samarium Modified Lead Titanate Ceramics for Hydroacoustic Applications.  

National Technical Information Service (NTIS)

Piezoelectric lead titanate ceramics are promising materials for applications in underwater acoustics as well as ultrasound technology. These materials are highly anisotropic and possess high sensitivity to hydroacoustic signals applied under hydrostatic ...

K. M. Rittenmyer R. Y. Ting

1990-01-01

170

The effect of foliar nutrition on yield of greenhouse tomatoes and quality of the crop  

Microsoft Academic Search

Tomatoes grown in traditional mediums such as peat moss are usually supplied with essential nutrients by preplant fertilization\\u000a and in the later growth stages by top dressing application to the root zone. According to the data from literature the efficient\\u000a method of nutrient supply during the intensive stage of growth may be estimated as by foliar spraying.\\u000a \\u000a In the greenhouse

Eugeniusz Ko?ota; Maria Osi?ska

2000-01-01

171

Spatial and temporal variability of foliar mineral concentration in beech (Fagus sylvatica) stands in northeastern France.  

PubMed

Foliar mineral concentration may provide a basis for monitoring the consequences of long-term environmental changes, such as eutrophication and acidification of soils, or increase in atmospheric CO(2) concentration. However, analytical drifts and inter-tree and year-to-year variations may confound environmental effects on long-term changes in foliar mineral concentration. We have characterized the relative effects of these potentially confounding factors on foliar carbon, nitrogen, phosphorus, calcium, potassium, magnesium and manganese concentrations in 118 pure beech (Fagus sylvatica L.) stands, sampled in 1969-71 and 1996-97. Interannual fluctuations of these elements were quantified in a subset of six beech stands monitored for 5 years. Intercalibration between the methods used at each sampling period for nitrogen and phosphorus analyses showed significant, but low, relative differences (0.8 and 3.3% for N and P, respectively). Based on inter-tree variability, elements could be arranged in four groups: C (constant), N and P (low variability), K and Ca (medium variability), Mn and Mg (high variability). Inter-tree coefficients of variation were 2, 6, 8, 15, 18, 22 and 27%, respectively. Year-to-year fluctuations increased in the order N, P, Mg, K, Ca, and Mn coefficients of variation of 4, 4, 7, 9, 11, 15 and 29%, respectively). Between the two sampling periods, foliar N concentration increased 12%, whereas decreases were observed for P (-23%), Mg (-38%) and Ca (-16%). Ratios of N/P, N/K and N/Mg increased by 42, 19 and 77%, respectively. These changes were larger than the interannual variations for P, Mg, N/P, N/Mg and Mg/Ca. Decreasing concentrations of P and cations were particularly marked for trees growing on acidic soils, whereas the positive N trend did not depend on soil type. Both increasing atmospheric CO(2) concentrations and acidification of forest soils could contribute to decreasing P and cation concentrations in foliage. The increase in foliar N concentration with time suggests a nitrogen deposition effect. Whatever the causes of these changes, the large shift in element ratios indicates an accelerating imbalance between nitrogen and cation status. PMID:12651522

Duquesnay, A.; Dupouey, J. L.; Clement, A.; Ulrich, E.; Le Tacon, F.

2000-01-01

172

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

173

Design and application of chitosan/biphasic calcium phosphate porous scaffolds for bone tissue engineering  

NASA Astrophysics Data System (ADS)

For the restoration of maxillofacial bone tissue, design of novel tissue engineering scaffolds capable of inducing bone remodeling through the delivery of mesenchymal stem cells (MSCs) and an angiogenic growth factor, directly at the site of the defect was investigated in order to replace autogenous cancellous bone grafts with synthetic materials. Porous, three dimensional scaffolds were fabricated by a freeze drying method. In culture media, biphasic calcium phosphate particles within chitosan produced a surface reprecipitate of a composition similar to natural apatite that led to a uniform distribution of cells and mineralized ECM through chemotaxis. Further, the reprecipitation regulated the differentiation pathway and phenotype commitment of stem cells by altering the initial cell attachment morphology and actin cytoskeleton organization. In order to induce neovascularization after implantation, constructs were designed to be loaded with gelatin microspheres that delivered basic fibroblast growth factor (bFGF), a potent angiogenic factor. In vitro proliferation tests performed on fibroblastic cells showed no detectible loss of bFGF activity when delivered through enzymatic degradation of gelatin. Laser scanning confocal microscopy was used to demonstrate that gelatin microspheres can be injected evenly into cell-scaffold constructs owing to the spongy characteristics of the scaffold. To examine the binding interactions of bFGF with surface bound gelatin, a label free biosensor system, Biomolecular INteraction Detection sensor (BIND) was used. Results confirm that the principal interaction that takes place between bFGF and gelatin is electrostatic. Cell loaded tissue engineered constructs were produced in vitro at clinically relevant sizes and implanted with and without bFGF into a porcine mandibular defect model. Tissue engineered constructs facilitated the healing of mandibular defects only if combined with delivery of bFGF via gelatin microspheres. bFGF release from the constructs improved neovascularization in the defect area and subsequently enhanced new bone formation. Although the rate and extent of bone formation was similar in bFGF group to those in empty defects for the period of the study, existence of woven bone in bFGF group suggests that bone formation is continuing while the lamellar structure in empty defects indicates that bone formation in that group was finalized.

Sendemir-Urkmez, Aylin

174

[Calcium antagonists: current and future applications based on new evidence. The mechanisms on lowering serum uric acid level by calcium channel blockers].  

PubMed

In hypertensive subjects, their serum uric acid levels tend to be higher because of decreasing urinary secretion or overproduction of uric acid. Among calcium channel blockers (CCBs) , long acting nifedipine and cilnidipine reveal serum uric acid lowering action. They decrease the production of uric acid precursor in skeletal muscles under anaerobic condition induced by hypertension or insulin resistance. Hyperuricemia is considered to be a risk factor of not only gout but also renal and cardiovascular diseases, thus, it is important to use CCBs without adverse effect on uric acid metabolisms. PMID:20048433

Mizuta, Einosuke; Hamada, Toshihiro; Igawa, Osamu; Shigemasa, Chiaki; Hisatome, Ichiro

2010-01-01

175

Effects of rapid application of caffeine on intracellular calcium concentration in ferret papillary muscles  

Microsoft Academic Search

In this paper we investigate the effects of caffeine (5-20 mM) on fer- ret papillary muscle. The intracellular Ca 2+ concentration ((Ca~+)i) was measured from the light emitted by the photoprotein aequorin, which had previously been microinjected into superficial cells. Isometric tension was measured simulta- neously. The rapid application of caffeine produced a transient increase of (Ca2+)i, which decayed spontaneously

G. L. Smith; M. VALDEOLMILLOS; D. A. EISNER; D. G. ALLEN

1988-01-01

176

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

SciTech Connect

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

Anderson, P.D.; Houpis, J.L.J. (Lawrence Livermore National Lab., CA (United States))

1991-05-01

177

Bulk physicochemical, interconnectivity, and mechanical properties of calcium phosphate cements-fibrin glue composites for bone substitute applications.  

PubMed

Calcium phosphate cements (CPCs) and fibrin glue (FG) are used for surgical applications. Their combination is promising to create bone substitutes able to promote cell attachment and bone remodeling. This study proposes a novel approach to create CPC-FG composites by simultaneous CPC setting and FG fibrinogenesis. CPC-FG composites were obtained by mixing CPC powders, i.e. ?-tricalcium phosphate, dicalcium phosphate anhydrous and precipitated hydroxyapatite, with FG powder components, i.e. fibrinogen and thrombin, and a 2% Na(2) HPO(4) solution. To study the effect of FG quantity and fibrinogenesis kinetics, long and fast setting FGs were evaluated in amounts of 0.125, 0.250, and 0.500 mL on CPC-FG composites. Physicochemical, interconnectivity, and mechanical properties were measured. Scanning electron microscopy, Micro-computed tomography (?-CT), X-ray diffraction, and Fourier transform Infrared spectroscopy (FTIR) analyzed morphology, structure, crystallographic, and chemical composition, respectively. FG fibrinogenesis was performed within the CPC. FTIR confirmed this and its interfacial bonding with CPC. ?-CT confirmed a good FG distribution. FG addition affected the CPC when compared with pristine CPC. Adding FG to CPC changed their morphology, density, porosity, setting, cohesion, injectability, interconnectivity, crystallographic and chemical composition and mechanical properties. Moreover, 0.500 mL of long setting FG modified the observed fracture behavior of the CPC-FG. PMID:22927324

Lopez-Heredia, M A; Pattipeilohy, J; Hsu, S; Grykien, M; van der Weijden, B; Leeuwenburgh, S C G; Salmon, P; Wolke, J G C; Jansen, J A

2012-08-28

178

Mupirocin Calcium  

Center for Drug Evaluation (CDER)

Text Version... Contains Nonbinding Recommendations Draft Guidance on Mupirocin Calcium ... Active ingredient: Mupirocin Calcium Form/Route: Cream/Topical ... More results from www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation

179

Calcium Calculator  

MedlinePLUS

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180

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

SciTech Connect

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

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

2011-04-01

181

Optical nanosensors for chemical analysis inside single living cells. 2. Sensors for pH and calcium and the intracellular application of PEBBLE sensors.  

PubMed

Optical nanosensors, or PEBBLEs (probes encapsulated by biologically localized embedding), have been produced for intracellular measurements of pH and calcium. Five varieties of pH-sensitive sensors and three different calcium-selective sensors are presented and discussed. Each sensor combines an ion-selective fluorescent indicator and an ion-insensitive internal standard entrapped within an acrylamide polymeric matrix. Calibrations and linear ranges are presented for each sensor. The photobleaching of dyes incorporated into PEBBLEs is comparable to that of the respective free dye that is incorporated within the matrix. These PEBBLE sensors are fully reversible over many measurements. The leaching of fluorescent indicator from the polymer is less than 50% over a 48-h period (note that a typical application time is only a few hours). The PEBBLE sensors have also been applied to intracellular analysis of the calcium flux in the cytoplasm of neural cells during the mitochondrial permeability transition. Specifically, a distinct difference is noted between cells of different types (astrocyte vs neuron-derived cells) with respect to their response to the toxicant m-dinitrobenzene (DNB). Use of PEBBLE sensors permits the quantitative discrimination of subtle differences between the ability of human SY5Y neuroblastoma and C6 glioma to respond to challenge with DNB. Specifically, measurement of intracellular calcium, the precursor to cell death, has been achieved. PMID:10565275

Clark, H A; Kopelman, R; Tjalkens, R; Philbert, M A

1999-11-01

182

Foliar Symptoms of Mineral Disorders in Desmodium intortum.  

National Technical Information Service (NTIS)

Foliar symptoms of twelve mineral deficiencies and two toxicities in Desmodium intortum cv. Greenleaf grown in water culture are described and recorded photographically. Information is also given on the concentrations of the various mineral elements in th...

C. S. Andrew W. H. J. Pieters

1972-01-01

183

Calcium Channels  

NASA Astrophysics Data System (ADS)

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

Corry, Ben; Hool, Livia

184

Hybrid Laser/Aerosol Method for the Synthesis of Porous Nanostructured Calcium Phosphate Materials for Bone Tissue Engineering Applications.  

National Technical Information Service (NTIS)

We present a new synthesis method based on laser generation and processing of aerosol particles that can produce calcium phosphate coatings in a porous nanostructured configuration. The process uses laser ablation of crystalline hydroxyapatite targets to ...

H. Kim R. P. Camata S. Brown

2005-01-01

185

Regional Assessment of N Saturation using Foliar and Root  

Microsoft Academic Search

N saturation induced by atmospheric N deposition can have serious consequences for forest health in many regions. In order to evaluate whether foliar $$\\\\delta^{15}\\\\hbox{N}$$ may be a robust, regional-scale measure of the onset of N saturation in forest ecosystems, we assembled a large dataset on atmospheric N deposition, foliar and root $$\\\\delta^{15}\\\\hbox{N}$$ and N concentration, soil C:N, mineralization and nitrification.

L. H. Pardo; P. H. Templer; C. L. Goodale; S. Duke; P. M. Groffman; M. B. Adams; P. Boeckx; J. Boggs; J. Campbell; B. Colman; J. Compton; B. Emmett; P. Gundersen; J. Kjønaas; G. Lovett; M. Mack; A. Magill; M. Mbila; M. J. Mitchell; G. McGee; S. McNulty; K. Nadelhoffer; S. Ollinger; D. Ross; H. Rueth; L. Rustad; P. Schaberg; S. Schiff; P. Schleppi; J. Spoelstra; W. Wessel

2006-01-01

186

Ecological ramifications of the direct foliar uptake of nitrogen  

Microsoft Academic Search

The foliar incorporation of various reactive forms of nitrogen (N) has been identified and studied for nearly 30 years. However,\\u000a the ecosystem-level ramifications of this uptake pathway have only recently been considered by the scientific community. In\\u000a this review, I present our current understanding of the foliar uptake process and then discuss why this pathway of N addition\\u000a to ecosystems should

Jed P. Sparks

2009-01-01

187

Salinity-induced calcium deficiencies in wheat and barley  

Microsoft Academic Search

Salinity-calcium interactions, which have been shown to be important in plants grown in dryland saline soils of the Canadian prairies, were studied in two species differing in salt tolerance. In solution culture, wheat showed a greater reduction in growth and a higher incidence of foliar Ca deficiency symptoms than barley when grown under MgSO4 or Na2SO4 plus MgSO4 salt stress.

D. L. Ehret; R. E. Redmann; B. L. Harvey; A. Cipywnyk

1990-01-01

188

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

EPA Science Inventory

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

189

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

190

Vector control and foliar nutrition to maintain economic sustainability of bearing citrus in Florida groves affected by huanglongbing.  

PubMed

BACKGROUND: Huanglongbing (HLB) or citrus greening is a bacterial disease vectored by the Asian citrus psyllid (ACP) causing tree decline, and yield loss. Vector control and foliar nutrition are used in Florida to slow the spread of HLB and mitigate debilitating effects of the disease. A four year replicated field study was initiated February 2008 in a 5.2-ha commercial block of young 'Valencia' orange trees employing a factorial design to evaluate individual and compound effects of vector management and foliar nutrition. Insecticides were sprayed during tree dormancy and when psyllid populations exceeded a nominal threshold. A mixture consisting primarily of micro- and macro-nutrients was applied three times a year corresponding to the principal foliar flushes. RESULTS: Differences in ACP numbers from five- to 13-fold were maintained in insecticide treated and untreated plots. Incidence of HLB estimated by polymerase chain reaction (PCR), rose from 30% at the beginning of the study to 95% in only 18 months. Highest yields all four years were seen from trees receiving both foliar nutrition and vector control. Production for these trees in the fourth year was close to the pre-HLB regional average for 10 year old 'Valencia' on 'Swingle'. Nevertheless, at current juice prices, the extra revenue generated from the combined insecticide and nutritional treatment did not cover the added treatment costs. CONCLUSIONS: This experiment demonstrated that vector control, especially when combined with enhanced foliar nutrition, could significantly increase yields in a citrus orchard with high incidence of HLB. Economic thresholds for both insecticide and nutrient applications are needed under different market and environmental conditions. PMID:23666807

Stansly, Philip A; Arevalo, H Alejandro; Qureshi, Jawwad A; Jones, Moneen M; Hendricks, Katherine; Roberts, Pamela D; Roka, Fritz M

2013-05-11

191

Foliar Injury, Tree Growth and Mortality, and Lichen Studies in Mammoth Cave National Park.  

National Technical Information Service (NTIS)

Foliar condition, tree growth, tree mortality, and lichen communities were studied in Mammoth Cave National Park, Kentucky, to document the present forest condition and to provide a basis for detecting future changes. Foliar injury by ozone was common on ...

B. McCune C. L. Cloonan T. V. Armentano

1987-01-01

192

Enhanced selenium content in buckwheat ( Fagopyrum esculentum Moench) and pumpkin ( Cucurbita pepo L.) seeds by foliar fertilisation  

Microsoft Academic Search

The fruit and thin-husked seeds of the pumpkin ( Cucurbita pepo L.) and buckwheat grain ( Fagopyrum esculentum Moench), both grown in Slovenia, were analysed for selenium (Se) content following foliar application of Se(VI) solution during the period of blooming. Samples were digested by a H 2SO 4-HNO 3-H 2O 2-V 2O 5 mixture and Se determined, based on hydride

Vekoslava Stibilj; Ivan Kreft; Polona Smrkolj; Jože Osvald

2004-01-01

193

Application of impedance spectroscopy to evaluate the effect of different setting accelerators on the developed microstructures of calcium phosphate cements  

Microsoft Academic Search

The main goal of the present study was to evaluate the effect of different setting accelerator agents on the developed microstructures\\u000a of calcium phosphate cements (CPCs) by employing the impedance spectroscopy (IS) technique. Six compositions of CPCs were\\u000a prepared from mixtures of commercial dicalcium phosphate anhydrous (DCPA) and synthesized tetracalcium phosphate (TTCP) as\\u000a the solid phases. Two TTCP\\/DCPA molar ratios

H. E. Romeo; P. R. Bueno; M. A. Fanovich

2009-01-01

194

Effects of water table depth and calcium perioxide application on cowpea ( Vigna unguiculata ) and soybean ( Glycine max )  

Microsoft Academic Search

Summary  The effects of three water table (WT) depths (0, 15 and 40 cm) and calcium peroxide (Calper) on the growth and yield of cowpea\\u000a (Vigna unguiculata, L.) and soybean (Glycine max) were investigated in field lysimeters for a sandy loam soil. Cowpea growth was the best at 40 cm WT depth. Leaf area, plant\\u000a height, dry matter production, number of

L. T. Ogunremi; R. Lal; O. Babalola

1981-01-01

195

Foliar moisture content of Pacific Northwest vegetation and its relation to wildland fire behavior  

Microsoft Academic Search

Foliar moisture was monitored for five conifers and associated understory vegetation in Pacific Northwest forests. Decline in foliar moisture of new foliage occurred over the dry season, while less variation was evident in older foliage. Late season foliar moisture ranged from 130 to 170%. In riparian–upland comparisons, largest differences were found for understory vegetation, with less variation evident for overstory

James K. Agee; Clinton S. Wright; Nathan Williamson; Mark H. Huff

2002-01-01

196

Epiderme dos segmentos foliares de Mauritia flexuosa L. f. (Arecaceae) em três fases de desenvolvimento  

Microsoft Academic Search

RESUMO São apresentados os dados anatômicos da epiderme dos segmentos foliares de Mauritia flexuosa L. f. (Arecaceae) em três fases do desenvolvimento. Os segmentos foliares foram analisados em toda a extensão do limbo. As células intercostais da epiderme das faces adaxial e abaxial evidenciam-se com paredes sinuosas, retangulares e orientadas longitudinalmente em relação ao eixo do segmento foliar com acentuada

Mahedy Araújo Bastos Passos; Maria Sílvia de Mendonça

2006-01-01

197

Calcium Phosphate  

Microsoft Academic Search

Early childhood dental caries is defined by its complex etiology of intersecting causations. Diet in combination with good\\u000a oral hygiene, is the most prominently alterable component of this etiology.\\u000a \\u000a Providing enough calcium phosphate in the diet of the pregnant and nursing mother and eventually in the weaning infant ensures\\u000a that a prominent component (calcium phosphate deficiency) of the complex diagram

Rainy Dawn Warf; Ronald Ross Watson

198

Foliar spirality and aestivation of flowers in Hibiscus cannabinus Linn  

Microsoft Academic Search

Summary InHibiscus cannabinus a negative association exists between the foliar spirality and the aestivation of corolla. Moreover, it is seen that the fruits developed from left-twiting flowers of left-spiralled plants and those of the right-twisting flowers of right-spiralled plants are better in quality.

S. S. Ghosh; T. A. Davis

1978-01-01

199

Foliar flavonoids of Annonaceae from Brazil: taxonomic significance  

Microsoft Academic Search

Foliar flavonoids of 31 species of the Annonaceae native to Brazil, amounting to 76 compounds, were isolated and identified. All phenols found were glycosides of either flavones (apigenin, scutellarein, hispidulin and luteolin) or flavonols (kaempferol, rhamnocitrin, 6-hydroxyrhamnocitrin, quercetin, isorhamnetin and rhamnetin), with the latter predominating. Some members of the tribe Bocageeae are distinctive for accumulating 6-oxygenated flavones and flavonols, in

D. Y. A. C. Santos; M. L. F. Salatino

2000-01-01

200

Systematic distribution of foliar trichome types in Croton (Euphorbiaceae)  

Microsoft Academic Search

Variation in foliar trichomes inCroton(Euphorbiaceae) is reviewed, and the terminology clarified by redefinitions and illustrations of terms. Evolution of trichome types appears to proceed from branched (stellate or fasciculate) hairs to simple and dendritic ones. A systematic enumeration characterizes the trichome morphology in 36 of the 40 sections, with citation of the 120 species examined.

G. L. WEBSTER; M. J. DEL-ARCO-AGUILAR; B. A. SMITH

1996-01-01

201

Foliar biofilms of Burkholderia pyrrocinia FP62 on geraniums  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

202

The Mauna Loa environmental matrix: foliar and soil nutrients  

Microsoft Academic Search

The accumulation of total carbon, nitrogen, and phosphorus in soils, available soil nutrients, and foliar nutrients in the native dominant Metrosideros polymorpha were determined across a wide elevational range on 9 lava flows on Mauna Loa, Hawai'i. The flows included a young (2800 y) áá (rough surface texture) and pahoehoe (smooth) flow on the wet east and dry northwest side

Peter M. Vitousek; Gregory Aplet; Douglas Turner; John J. Lockwood

1992-01-01

203

Estimating the foliar biochemical concentration of leaves with reflectance spectrometry  

Microsoft Academic Search

In an effort to further develop the methods needed to remotely sense the biochemical concentration of plant canopies, we report the results of an experiment to estimate the concentration of 12 foliar biochemicals (chlorophyll a, chlorophyll b, total chlorophyll, lignin, nitrogen, cellulose, water, phosphorous, protein, amino acids, sugar, starch) from reflectance spectra of dried and ground slash pine needles. The

Paul J Curran; Jennifer L Dungan; David L Peterson

2001-01-01

204

Calcium carbonate overdose  

MedlinePLUS

Tums overdose; Calcium overdose ... Calcium ... Products containing calcium carbonate, including Certain antacids (Tums, Chooz) Certain mineral supplements Certain hand lotions Certain vitamin and mineral supplements Note: ...

205

Minerals Yearbook 1991: Calcium and Calcium Compounds.  

National Technical Information Service (NTIS)

Calcium, is chemically very active and is found in a host of minerals that occur in nearly every geologic environment. Calcium fluoride is sold as fluorspar; calcium sulfate as gypsum or anhydrite; calcium oxide and hydroxide as lime; calcium phosphate as...

M. M. Miller

1992-01-01

206

Minerals Yearbook, 1988. Calcium and Calcium Compounds.  

National Technical Information Service (NTIS)

The Bureau of Mines publishes reports for a variety of calcium-containing minerals and compounds because of their commercial significance and contribution to the quality of human life. The report includes calcium metal, calcium chloride, and various other...

D. E. Morse

1988-01-01

207

Immobilization of tomato (Lycopersicon esculentum) pectinmethylesterase in calcium alginate beads and its application in fruit juice clarification.  

PubMed

Clarity of fruit juices is desirable to maintain an aesthetically pleasing quality and international standards. The most commonly used enzymes in juice industries are pectinases. A partially-purified pectinmethylesterase from tomato was entrapped in calcium alginate beads and used for juice clarification. The activity yield was maximum at 1 % (w/v) CaCl2 and 2.5 % (w/v) alginate. The immobilized enzyme retained ~55 % of its initial activity (5.7 × 10(-2) units) after more than ten successive batch reactions. The Km, pH and temperature optima were increased after immobilization. The most effective clarification of fruit juice (%T620 ~60 %) by the immobilized enzyme was at 4 °C with a holding time of 20 min. The viscosity dropped by 56 % and the filterability increased by 260 %. The juice remains clear after 2 months of storage at 4 °C. PMID:23881317

Bogra, Pushpa; Kumar, Ashwani; Kuhar, Kalika; Panwar, Surbhi; Singh, Randhir

2013-07-24

208

Foliar urea fertilization of cereals: A review  

Microsoft Academic Search

It has been suggested that there are several potential benefits of providing nitrogen to cereals via the foliage as urea solution. These include: reduced nitrogen losses through denitrification and leaching compared with nitrogen fertilizer applications to the soil; the ability to provide nitrogen when root activity is impaired e.g., in saline or dry conditions, and uptake late in the season

M. J. Gooding; W. P. Davies

1992-01-01

209

In vitro evaluation of biomimetic chitosan-calcium phosphate scaffolds with potential application in bone tissue engineering.  

PubMed

This work reports on the physicochemical properties and in vitro cytotoxicity assessment of chitosan-calcium phosphate (Cs-CP) scaffolds for bone tissue engineering, which were synthesized by a novel biomimetic co-precipitation method. X-ray diffraction (XRD) along with scanning electron microscopy (SEM) analysis confirmed the porous morphology of the scaffolds and the amorphous nature of the inorganic phase with different crystallite sizes and the formation of various forms of calcium phosphate. Compressive mechanical testing revealed that the Young's modulus of the biomaterials is in the range of human trabecular bone. In vitro tests were performed on the biomaterials for up to 14 days to study the behavior of the osteoblast-like human cell line (MG63), primary human osteoblasts (HOS) and human dermal microvascular endothelial cells (HDMEC). The cytotoxicity was evaluated by the MTS assay for cell metabolism and the detection of membrane integrity (lactate dehydrogenase-LDH release). An expression of the vascular endothelial growth factor (VEGF) in the cell supernatants was quantified by ELISA. Cell viability gave values close to untreated controls for MG63 and HOS, while in the case of HDMEC the viability after 2 weeks in the cell culture was between 80-90%. The cytotoxicity induced by the Cs-CP scaffolds on MG63, HOS and HDMEC in vitro was evaluated by the amount of LDH released, which is a sensitive and accurate marker for cellular toxicity. The increased levels of VEGF obtained in the osteoblast culture highlights its important role in the regulation of vascularization and bone remodeling. The biological responses of the Cs-CP scaffolds demonstrate a similar proliferation and differentiation characteristics of the cells comparable to the controls. These results reveal that biomimetic Cs-CP composite scaffolds are promising biomaterials for bone tissue engineering; their in vivo response remains to be tested. PMID:23343569

Tanase, C E; Sartoris, A; Popa, M I; Verestiuc, L; Unger, R E; Kirkpatrick, C J

2013-01-23

210

Intestinal hyperabsorption of oxalate in calcium oxalate stone formers: application of a new test with [13C2]oxalate.  

PubMed

In up to one-third of patients with calcium oxalate stones, a hyperoxaluria can be detected. Hyperoxaluria can result from increased endogenous production, from excessive oxalate content of the food, or from intestinal hyperabsorption. For a causal therapy, it is important to discriminate between metabolic and hyperabsorptive hyperoxaluria. Our new 13C-oxalate test allows this differentiation. Under standardized conditions, 50 mg of disodium salt of [13C2]oxalic acid was applied. From the amount of labeled oxalate excreted in urine as measured by a gas chromatographic-mass spectrometric assay, the intestinal absorption was calculated. Seventy patients with recurrent calcium oxalate urolithiasis who had no signs of inflammatory bowel disease were tested. Their mean intestinal oxalate absorption was 9.2+/-5.1%. This was significantly higher than the mean absorption of 50 healthy volunteers (6.7+/-3.9%). There was no difference in oxalate absorption between male (n = 25) and female volunteers. Oxalate absorption correlated with the oxalate excretion in the 24-h urine (volunteers: r = 0.46, P < 0.01; patients: r = 0.62, P < 0.001). Oxalate hyperabsorption was defined as an absorption exceeding 10%. According to this definition, 34% of the patients had oxalate hyperabsorption; 20% of the volunteers showed a hyperabsorption, too. The 13C-oxalate absorption test allows reliable determination of intestinal oxalate absorption. Because of the use of a stable isotope, this test may be repeated as often as required. It will allow the control of therapeutic regimens and also help to unravel genetic influences in stone formation. PMID:10541257

Hesse, A; Schneeberger, W; Engfeld, S; Von Unruh, G E; Sauerbruch, T

1999-11-01

211

Role of calcium in gravity perception of plant roots.  

PubMed

Calcium ions may play a key role in linking graviperception by the root cap to the asymmetric growth which occurs in the elongation zone of gravistimulated roots. Application of calcium-chelating agents to the root cap inhibits gravitropic curvature without affecting growth. Asymmetric application of calcium to one side of the root cap induces curvature toward the calcium source, and gravistimulation induces polar movement of applied 45Ca2+ across the root cap toward the lower side. The action of calcium may be linked to auxin movement in roots since 1) auxin transport inhibitors interfere both with gravitropic curvature and gravi-induced polar calcium movement and 2) asymmetric application of calcium enhances auxin movement across the elongation zone of gravistimulated roots. Indirect evidence indicates that the calcium-modulated regulator protein, calmodulin, may be involved in either the transport or action of calcium in the gravitropic response mechanism of roots. PMID:11537844

Evans, M L

1986-01-01

212

Project Calcium  

SciTech Connect

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

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

1992-09-01

213

Meta-analysis of yield response of hybrid field corn to foliar fungicides in the U.S. Corn Belt.  

PubMed

The use of foliar fungicides on field corn has increased greatly over the past 5 years in the United States in an attempt to increase yields, despite limited evidence that use of the fungicides is consistently profitable. To assess the value of using fungicides in grain corn production, random-effects meta-analyses were performed on results from foliar fungicide experiments conducted during 2002 to 2009 in 14 states across the United States to determine the mean yield response to the fungicides azoxystrobin, pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin. For all fungicides, the yield difference between treated and nontreated plots was highly variable among studies. All four fungicides resulted in a significant mean yield increase relative to the nontreated plots (P < 0.05). Mean yield difference was highest for propiconazole + trifloxystrobin (390 kg/ha), followed by propiconazole + azoxystrobin (331 kg/ha) and pyraclostrobin (256 kg/ha), and lowest for azoxystrobin (230 kg/ha). Baseline yield (mean yield in the nontreated plots) had a significant effect on yield for propiconazole + azoxystrobin (P < 0.05), whereas baseline foliar disease severity (mean severity in the nontreated plots) significantly affected the yield response to pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin but not to azoxystrobin. Mean yield difference was generally higher in the lowest yield and higher disease severity categories than in the highest yield and lower disease categories. The probability of failing to recover the fungicide application cost (p(loss)) also was estimated for a range of grain corn prices and application costs. At the 10-year average corn grain price of $0.12/kg ($2.97/bushel) and application costs of $40 to 95/ha, p(loss) for disease severity <5% was 0.55 to 0.98 for pyraclostrobin, 0.62 to 0.93 for propiconazole + trifloxystrobin, 0.58 to 0.89 for propiconazole + azoxystrobin, and 0.91 to 0.99 for azoxystrobin. When disease severity was >5%, the corresponding probabilities were 0.36 to 95, 0.25 to 0.69, 0.25 to 0.64, and 0.37 to 0.98 for the four fungicides. In conclusion, the high p(loss) values found in most scenarios suggest that the use of these foliar fungicides is unlikely to be profitable when foliar disease severity is low and yield expectation is high. PMID:21554185

Paul, P A; Madden, L V; Bradley, C A; Robertson, A E; Munkvold, G P; Shaner, G; Wise, K A; Malvick, D K; Allen, T W; Grybauskas, A; Vincelli, P; Esker, P

2011-09-01

214

Effect of the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste and adhesive systems on bond durability of a fissure sealant.  

PubMed

This study aimed to evaluate the effect of the previous application of a casein phosphopeptide-amorphous calcium phosphate paste (MI Paste, MI) and adhesive systems on the bond durability of a fissure sealant. Ninety-eight enamel blocks were obtained from proximal surfaces of erupted third molars. Specimens were divided into 14 groups (n = 7) according to the previous application of MI (with and without) and the adhesive systems used (no adhesive system; hydrophobic resin of a three-step etch-and-rinse adhesive system; etch-and-rinse single-bottle adhesive system; all-in-one adhesive system; two-step self-etching adhesive system; additional phosphoric acid conditioning and all-in-one adhesive system; additional phosphoric acid conditioning and two-step self-etching adhesive system). A fissure sealant (Fluroshield) was applied and photoactivated for 20 s. Beams (~0.7 mm(2)) were prepared for the microtensile bond strength test, which was executed after 24 h or 6 months of water storage. Fractured specimens were analyzed by scanning electronic microscopy. Data were analyzed by two-way ANOVA with repeated measures/Tukey's test (P < 0.05). Groups that received MI application and adhesive systems presented higher means than those groups where MI was not applied. Higher frequency of cohesive failures was observed for groups with MI. Applying a CPP-ACP containing paste on enamel before adhesive systems was an effective method to increase bond durability of the sealant tested. PMID:22438086

Borges, Boniek Castillo Dutra; Catelan, Anderson; Sasaki, Robson Tetsuo; Ambrosano, Gláucia Maria Bovi; Reis, André Figueiredo; Aguiar, Flávio Henrique Baggio

2012-03-22

215

Estimating foliar water content of winter wheat with hyperspectral image  

NASA Astrophysics Data System (ADS)

Estimates of vegetation water content are of great interest for assessing vegetation water status in agriculture and forestry, and have been used for drought assessment. This study focuses on the retrieval of foliar water content with hyperspectral data at canopy level. The hyperspectral image used in this study was acquired by the airborne operative modular imaging spectrometer (OMIS) at Demonstration Site for Precision Agriculture in Xiaotangshan area, Beijing, on April 26th, 2001. 40 image spectra were extracted to correspond to the quasi-synchronous meansurements of foliar water content (FWC). The image spectra of winter wheat were utilized to validate the sensitivity of the existing and novel water indices and parameters of three water absorption features in NIR and SWIR regions. Correlation analysis showed that, NDWI(860,1241) and NDWI(860,1200) both had significant linear relationships with FWC (R2 were 0.4124 and 0.4042 respectively). Red edge position (REP) could reflect indirectly the variations of wheat FWC to some extent. Significant linear relationships were also found between WI(820,1600) and FWC, and between WI(900,1200) and FWC, while no relationship was shown between the traditional WI(900,970) and FWC. The derived depth of water absorption centered around 2078nm, namely AD2078, had the highest linear correlation with FWC (R2 is 0.4551) , much higher than those parameters derived from the two water absorption around 1175 and 1409. In the end, AD2078 was applied to OMIS image to map the foliar water content. The value range of the inverted foliar water content ranged from 69.39 to 78.35%, which was quite close to that of the field measurements (70.72-78.12%). The distribution of the FWC map was quite consistent with growth status of winter wheat.

Zhang, Xia; Jiao, Quanjun; Wu, Di; Zhang, Bing; Gao, Lianru

2007-11-01

216

Calcium and bone disease  

PubMed Central

Calcium transport and calcium signaling are of basic importance in bone cells. Bone is the major store of calcium and a key regulatory organ for calcium homeostasis. Bone, in major part, responds to calcium-dependent signals from the parathyroids and via vitamin D metabolites, although bone retains direct response to extracellular calcium if parathyroid regulation is lost. Improved understanding of calcium transporters and calcium-regulated cellular processes has resulted from analysis of genetic defects, including several defects with low or high bone mass. Osteoblasts deposit calcium by mechanisms including phosphate and calcium transport with alkalinization to absorb acid created by mineral deposition; cartilage calcium mineralization occurs by passive diffusion and phosphate production. Calcium mobilization by osteoclasts is mediated by acid secretion. Both bone forming and bone resorbing cells use calcium signals as regulators of differentiation and activity. This has been studied in more detail in osteoclasts, where both osteoclast differentiation and motility are regulated by calcium.

Blair, Harry C.; Robinson, Lisa J.; Huang, Christopher L.-H.; Sun, Li; Friedman, Peter A.; Schlesinger, Paul H.; Zaidi, Mone

2013-01-01

217

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

PubMed

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

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

2013-07-26

218

Two-Step pH-Modulated Rapid Assembly of Trace-Element-Doped Calcium-Phosphate Nanocrystals into Giant Porous Beads in Gelatin Hydrosol for Biomedical Applications.  

PubMed

Biomolecule-ion interactions that occur during changes in pH value are a crucial but poorly investigated area that underlies the aggregation of inorganic nanocrystals. Meanwhile, the disorderly growth of calcium phosphate (CaP) nanocrystals is an obstacle that limits its practical applications. Herein, we have demonstrated for the first time that a simple two-step pH-adjustment process for a gelatin hydrosol reaction medium can modulate the ordered self-assembly of trace-element-doped CaP nanocrystals into porous beads. Two methods are used to adjust the initial pH value of gelatin hydrosol: One is to firstly adjust the pH value to 3.0 and then to 4.0 with acid/base solutions, whilst the other is to directly adjust the pH value to 4.0 with acid. Spherical CaP porous beads are rapidly produced through the two-step pH-adjustment process, whereas the one-step pathway results in disorderly CaP aggregates. We believe that the introduction of additives for pH adjustment is the dominant factor in disturbing the electrokinetic parameters and for driving the self-assembly of nanocrystals, whereas the nucleation of CaP nanocrystals prior to assembly is caused by the relaxation/condensation of the polypeptide network, owing to the increase in pH value on the introduction of the basic calcium salt. This method is facile and rapid and these highly bioactive porous beads are particularly promising for use in hard-tissue repair, tissue engineering, and drug delivery. PMID:23873742

Li, Zhicheng; Chen, Xiaoyi; Yang, Yongzhu; Yang, Xianyan; Zhang, Lei; Yang, Guojing; Tang, Ruikang; Gou, Zhongru

2013-07-19

219

Calcium Nephrolithiasis  

Microsoft Academic Search

Nephrolithiasis is a major cause of morbidity involving the urinary tract. The prevalence of this disease in the United States\\u000a increased from 3.8% in the 1970s to 5.2% in the 1990s. There were nearly 2 million physician office visits for nephrolithiasis\\u000a in 2000, and estimated annual costs totaled $2 billion. About 80% of stones are composed of calcium oxalate with

Zachary Z. BrenerJames; James F. Winchester; Michael Bergman

220

Staircase-like potentiation of calcium release in mouse myotubes during repetitive short-term application of threshold caffeine  

Microsoft Academic Search

The release of Ca2+ in response to caffeine at threshold concentration (5 mM) was studied in mouse skeletal myotubes. Repeated 5-s applications of caffeine, each followed by a 30-s washout, caused Ca2+ releases of consecutively growing amplitude (staircase phenomenon). Each response declined rapidly and had a slow tail. Repeated applications of threshold caffeine lowered the threshold concentration. The interval between

Philipp S. Lange; Reinhardt Rüdel; Stuart R. Taylor; Karl Föhr

2001-01-01

221

APPLICATION OF A BIOSOLID SOIL AMENDMENT, CALCIUM HYDROXIDE, AND STREPTOMYCES SP. FOR MANAGEMENT OF ROOT-KNOT NEMATODE ON CANTALOUPE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The biosolid soil amendment N-Viro SoilTM (NVS) and a Streptomyces sp. isolate (99-60) were tested for effects on root-knot nematode (RKN: Meloidogyne incognita (Kofoid & White) Chitwood) egg populations on cantaloupe (Cucumis melo L.). Application of NVS at 3% (dry w/w) in the soil mixture resulte...

222

Fructose 1,6-bisphosphate trisodium salt as a new phosphorus source for the rapid microwave synthesis of porous calcium-phosphate microspheres and their application in drug delivery.  

PubMed

Calcium phosphates (CPs), as the major inorganic component of biological hard tissues, have been investigated for applications as biomaterials owing to their excellent biocompatibility. However, the traditional synthetic CPs are usually prepared from inorganic phosphorus and calcium sources. Herein, we report a new strategy for the synthesis of a variety of calcium-phosphate nanostructures, including porous amorphous calcium phosphate (ACP) microspheres, hydroxyapatite (HAP) nanorods, and ACP/HAP composite microspheres, by using fructose 1,6-bisphosphate trisodium salt (FBP) as an organic phosphorus source in aqueous solution in a rapid microwave-assisted hydrothermal reaction. The important role of FBP and the effect of the experimental conditions on the formation and evolution of the CPs nanostructures were investigated. The crystal phase and composition of the as-prepared products were characterized by powder X-ray diffraction (XRD), FTIR spectroscopy, and thermogravimetric (TGA) analysis and the morphologies of the products were characterized by SEM and TEM. This method is facile, rapid, surfactant-free, and environmentally friendly. The as-prepared porous ACP microspheres have a relatively high drug-loading capacity and good sustained drug-release behavior; thus, they are promising for applications in drug delivery. PMID:23192854

Qi, Chao; Zhu, Ying-Jie; Chen, Feng

2012-11-28

223

Foliar anthocyanin content - Sensitivity of vegetation indices using green reflectance  

NASA Astrophysics Data System (ADS)

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

Vina, A.; Gitelson, A. A.

2009-12-01

224

Calcium Isotope Analysis by Mass Spectrometry  

Microsoft Academic Search

The variations in the isotopic composition of calcium caused by fractionation in heterogeneous systems and by nuclear reactions can provide insight into numerous biological, geological, and cosmic processes, and therefore isotopic analysis finds a wide spectrum of applications in cosmo- and geochemistry, paleoclimatic, nutritional, and biomedical studies. The measurement of calcium isotopic abundances in natural samples has challenged the analysts

S. Boulyga; S. Richter

2010-01-01

225

Nanocrystalline calcium phosphate ceramics in biomedical engineering  

Microsoft Academic Search

Nanocrystalline calcium phosphate based bioceramics are the new rage in biomaterials research. Conventionally, calcium phosphates based materials are preferred as bone grafts in hard tissue engineering because of their superior biocompatibility and bioactivity. However, this group of bioceramics exhibits poor mechanical performance, which restricts their uses in load bearing applications. The recent trend in bioceramic research is mainly concentrated on

Samar J. Kalita; Abhilasha Bhardwaj; Himesh A. Bhatt

2007-01-01

226

Coronary Calcium Scan  

MedlinePLUS

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

227

Get Enough Calcium  

MedlinePLUS

... Physical Activity > Nutrition > Get Enough Calcium Get Enough Calcium The Basics Take Action! Ver en español Content ... August 28, 2013 The Basics Your body needs calcium to build strong bones when you are young ...

228

Calcium and bones (image)  

MedlinePLUS

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

229

Calcium and Bone Health  

MedlinePLUS

... to... Añadir en... Favorites Delicious Digg Google Bookmarks Calcium and Bone Health Bones play many roles in ... with osteoporosis, please visit the National Osteoporosis Foundation .* Calcium Calcium is a mineral needed by the body ...

230

Calcium source (image)  

MedlinePLUS

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

231

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

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

232

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

PubMed Central

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

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

2011-01-01

233

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

234

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

235

Ozone air pollution and foliar injury development on native plants of Switzerland  

Microsoft Academic Search

The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber

Kristopher Novak; John M. Skelly; Marcus Schaub; Norbert Krauchi; Christian Hug; Werner Landolt; Peter Bleuler

236

Essential Oil Variation of Salvia officinalis Leaves during Vegetation after Treatment with Foliar Fertilizer and Thidiazuron  

Microsoft Academic Search

The essential oil yield and chemical composition of Salvia officinalis L. (Dalmatica origin) have been analyzed. Leaf samples for essential oil analysis were harvested at different developmental stages after treatment with foliar fertilizer Agroleaf and foliar fertilizer + thidiazuron. In total, 10 constituents were identified and quantified. The main compounds in the essential oil that increased during the vegetative to

Ira Stancheva; Maria Geneva; Georgi Georgiev; Milka Todorova; Lyuba Evstatieva

2010-01-01

237

Ozone air pollution and foliar injury development on native plants of Switzerland  

Microsoft Academic Search

The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber

Kristopher Novak; John M. Skelly; Marcus Schaub; Norbert Kräuchi; Christian Hug; Werner Landolt; Peter Bleuler

2003-01-01

238

Purification of some Calcium and Magnesium Waste by Hydrodynamics Classification  

Microsoft Academic Search

In the manufacturing process of magnesium carbonate and oxide from dolomites by carbon dioxide leach ing are evacuated calcium carbonate waste, on one hand and on the other hand, in the carbide industry could be obtained calcium carbonate by practical application of some subsized lime fractions-containing waste. In order to obtai n calcium carbonate in different sorts as final products

L. M. Taubert; M. Milos; L. Sayti

239

Minerals Yearbook, 1989. Calcium and Calcium Compounds.  

National Technical Information Service (NTIS)

The Bureau of Mines publishes reports for a variety of calcium-containing minerals and compounds because of their commercial significance and contribution to the quality of human life. Calcium fluoride is sold as fluorspar; calcium sulfate as gypsum or an...

M. M. Miller

1990-01-01

240

Minerals Yearbook, 1990. Calcium and Calcium Compounds.  

National Technical Information Service (NTIS)

The U.S. Bureau of Mines publishes reports for a variety of calcium-containing minerals and compounds because of their commercial significance and contribution to the quality of human life. The 'Calcium and Calcium Compounds Annual Report' includes calciu...

M. M. Miller

1991-01-01

241

Comparing the applicability of some geostatistical methods to predict the spatial distribution of topsoil Calcium Carbonate in part of farmland of Zanjan Province  

NASA Astrophysics Data System (ADS)

Most of soils in iran, were located in the arid and semi-arid regions and have high pH (more than 7) and high amount of calcium carbonate and this problem cause to their calcification.In calcareous soils, plant growing and production is difficult. Most part of this problem, in relation to high pH and high concentration of calcium ion that cause to fixation and unavailability of elements which were dependent to pH, especially Phosphorous and some micro nutrients such as Fe, Zn, Mn and Cu. Prediction of soil calcium carbonate in non-sampled areas and mapping the calcium carbonate variability in order to sustainable management of soil fertility is very important.So, this research was done with the aim of evaluation and analyzing spatial variability of topsoil calcium carbonate as an aspect of soil fertility and plant nutrition, comparing geostatistical methods such as kriging and co-kriging and mapping topsoil calcium carbonate. For geostatistical analyzing, sampling was done with stratified random method and soil samples from 0 to 15 cm depth were collected with auger within 23 locations.In co-kriging method, salinity data was used as auxiliary variable. For comparing and evaluation of geostatistical methods, cross validation were used by statistical parameters of RMSE. The results showed that co-kriging method has the highest correlation coefficient and less RMSE and has the higher accuracy than kriging method to prediction of calcium carbonate content in non-sampled areas.

Sarmadian, Fereydoon; Keshavarzi, Ali

2010-05-01

242

Foliar Uptake of Atmospheric Reactive Nitrogen Pollution Along an Urban-Rural Gradient in New York State  

Microsoft Academic Search

Vegetation is an important sink for atmospheric reactive nitrogen (N) pollution in terrestrial ecosystems, and when soil N is limiting, foliar N uptake can be a source of plant-available N. A proxy for pollution derived N, and in particular foliar assimilated N, would be useful to quantify the impact of the foliar uptake pathway on plant metabolism. Nitrogen stable isotope

D. Vallano; J. P. Sparks

2008-01-01

243

Effects of different sources and rates of sulphur on the growth and foliar nutrition of nitrogen-fertilized lodgepole pine  

Microsoft Academic Search

The effects of nitrogen (N) fertilizer, alone and in combination with different sources and rates of sulphur (S), on foliar nutrients and tree growth are reported over 3 and 6 years, respectively. After 3 years, foliar S levels in the N+S treatments were significantly higher than those in N-only treatments at all six study locations. Temporal pat- terns of foliar

R. P. Brockley

2004-01-01

244

CALCIUM AND VITAMIN D  

Technology Transfer Automated Retrieval System (TEKTRAN)

Calcium is required for the bone formation phase of bone remodeling. An inadequate intake of calcium results in reduced calcium absorption. This stimulates hormone changes that induce bone remodeling. When the remodeling rate is high, bone loss occurs. With aging, calcium absorption efficiency d...

245

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

246

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

SciTech Connect

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

Solem-Tishmack, J.K.; McCarthy, G.J. [North Dakota State Univ., Fargo, ND (United States). Dept. of Chemistry; Docktor, B.; Eylands, K.E.; Thompson, J.S.; Hassett, D.J. [Univ. of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center

1995-04-01

247

Role of polyhydroxybutyrate in mitochondrial calcium uptake  

PubMed Central

Polyhydroxybutyrate (PHB) is a biological polymer which belongs to the class of polyesters and is ubiquitously present in all living organisms. Mammalian mitochondrial membranes contain PHB consisting of up to 120 hydroxybutyrate residues. Roles played by PHB in mammalian mitochondria remain obscure. It was previously demonstrated that PHB of the size similar to one found in mitochondria mediates calcium transport in lipid bilayer membranes. We hypothesized that the presence of PHB in mitochondrial membrane might play a significant role in mitochondrial calcium transport. To test this, we investigated how the induction of PHB hydrolysis affects mitochondrial calcium transport. Mitochondrial PHB was altered enzymatically by targeted expression of bacterial PHB hydrolyzing enzyme (PhaZ7) in mitochondria of mammalian cultured cells. The expression of PhaZ7 induced changes in mitochondrial metabolism resulting in decreased mitochondrial membrane potential in HepG2 but not in U87 and HeLa cells. Furthermore, it significantly inhibited mitochondrial calcium uptake in intact HepG2, U87 and HeLa cells stimulated by the ATP or by the application of increased concentrations of calcium to the digitonin permeabilized cells. Calcium uptake in PhaZ7 expressing cells was restored by mimicking calcium uniporter properties with natural electrogenic calcium ionophore - ferutinin. We propose that PHB is a previously unrecognized important component of the mitochondrial calcium uptake system.

Smithen, Matthew; Elustondo, Pia A.; Winkfein, Robert; Zakharian, Eleonora; Abramov, Andrey Y.; Pavlov, Evgeny

2013-01-01

248

Presynaptic Calcium Signalling in Cerebellar Mossy Fibres  

PubMed Central

Whole-cell recordings were obtained from mossy fibre terminals in adult turtles in order to characterize the basic membrane properties. Calcium imaging of presynaptic calcium signals was carried out in order to analyse calcium dynamics and presynaptic GABA B inhibition. A tetrodotoxin (TTX)-sensitive fast Na+ spike faithfully followed repetitive depolarizing pulses with little change in spike duration or amplitude, while a strong outward rectification dominated responses to long-lasting depolarizations. High-threshold calcium spikes were uncovered following addition of potassium channel blockers. Calcium imaging using Calcium-Green dextran revealed a stimulus-evoked all-or-none TTX-sensitive calcium signal in simple and complex rosettes. All compartments of a complex rosette were activated during electrical activation of the mossy fibre, while individual simple and complex rosettes along an axon appeared to be isolated from one another in terms of calcium signalling. CGP55845 application showed that GABA B receptors mediated presynaptic inhibition of the calcium signal over the entire firing frequency range of mossy fibres. A paired-pulse depression of the calcium signal lasting more than 1?s affected burst firing in mossy fibres; this paired-pulse depression was reduced by GABA B antagonists. While our results indicated that a presynaptic rosette electrophysiologically functioned as a unit, topical GABA application showed that calcium signals in the branches of complex rosettes could be modulated locally, suggesting that cerebellar glomeruli may be dynamically sub-compartmentalized due to ongoing inhibition mediated by Golgi cells. This could provide a fine-grained control of mossy fibre-granule cell information transfer and synaptic plasticity within a mossy fibre rosette.

Thomsen, Louiza B.; Jorntell, Henrik; Midtgaard, Jens

2009-01-01

249

Involvement of intracellular calcium in the phosphate efflux from mammalian nonmyelinated nerve fibers  

Microsoft Academic Search

Summary Phosphate efflux was measured as the fractional rate of loss of radioactivity from desheathed rabbit vagus nerves after loading with radiophosphate. The effects of strategies designed to increase intracellular calcium were investigated. At the same time, the exchangeable calcium content was measured using45Ca. Application of calcium ionophore A23187 increased phosphate efflux in the presence of external calcium in parallel

P. Jirounek; J. Vitus; G. J. Jones; W. F. Pralong; R. W. Straub

1984-01-01

250

Minerals: Calcium, Phosphorus, and Magnesium  

MedlinePLUS

... Minerals: Calcium, Phosphorus, and Magnesium Healthy Living Listen Minerals: Calcium, Phosphorus, and Magnesium Article Body Three minerals— calcium , phosphorus, and magnesium—account for 98% of ...

251

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

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

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

252

Shrimp pond effluent dominates foliar nitrogen in disturbed mangroves as mapped using hyperspectral imagery.  

PubMed

Conversion of mangroves to shrimp ponds creates fragmentation and eutrophication. Detection of the spatial variation of foliar nitrogen is essential for understanding the effect of eutrophication on mangroves. We aim (i) to estimate nitrogen variability across mangrove landscapes of the Mahakam delta using airborne hyperspectral remote sensing (HyMap) and (ii) to investigate links between the variation of foliar nitrogen mapped and local environmental variables. In this study, multivariate prediction models achieved a higher level of accuracy than narrow-band vegetation indices, making multivariate modeling the best choice for mapping. The variation of foliar nitrogen concentration in mangroves was significantly influenced by the local environment: (1) position of mangroves (seaward/landward), (2) distance to the shrimp ponds, and (3) predominant mangrove species. The findings suggest that anthropogenic disturbances, in this case shrimp ponds, influence nitrogen variation in mangroves. Mangroves closer to the shrimp ponds had higher foliar nitrogen concentrations. PMID:24103095

Fauzi, Anas; Skidmore, Andrew K; Gils, Hein van; Schlerf, Martin; Heitkönig, Ignas M A

2013-10-05

253

Calcium hydroxide poisoning  

MedlinePLUS

... powder produced by mixing calcium oxide ("lime") with water. Calcium hydroxide poisoning occurs when someone swallows this substance. This is for information only and not for use in the treatment or management of an actual poison exposure. If you have ...

254

Regional Assessment of N saturation using foliar and root ?15N  

Microsoft Academic Search

N saturation induced by atmospheric N deposition can have serious consequences for forest health in many regions. In order to evaluate whether foliar d15N may be a robust, regional-scale measure of the onset of N saturation in forest ecosystems, we assembled a large dataset on atmospheric N deposition, foliar and root d15N and N concentration, soil C:N, mineralization and nitrification.

L. H. Pardo; P. Templer; C. L. Goodale; S. Duke; P. Groffman; M. B. Adams; P. Boeckx; J. Boggs; J. Campbell; J. Compton; B. Emmett; P. Gundersen; G. Lovett; M. Mack; A. Magill; M. J. Mitchell; M. Mbila; G. McGee; S. McNulty; K. Nadelhoffer; B. Colman; S. Ollinger; D. Ross; H. Rueth; L. Rustad; P. Schaberg; S. Schiff; P. Schleppi; J. Spoelstra; W. Wessel

255

Tomato growth, nitrogen fraction and mineral composition in response to nitrate and ammonium foliar sprays  

Microsoft Academic Search

Tomato plants were grown in sand culture with NO3 or NH4 N at two levels of light. Foliar sprays at three levels of N as well as combinations of foliar and root feeding were used.Shade increased NH4 toxicity in plants sprayed with NH4 but decreased the toxicity in plants receiving NH4 through the roots. NH4?N greatly reduced growth and cation

Jose R. Magalhaes; G. E. Wilcox

1983-01-01

256

Foliar 15 N natural abundance in Hawaiian rainforest: patterns and possible mechanisms  

Microsoft Academic Search

Foliar samples were obtained from symbiotic nitrogen-fixers and control plants (non-fixers) along elevational and primary successional gradients in volcanic sites in Hawai'i. Most control plants had negative d15N values (range-10.1 to +0.7‰), while most nitrogen-fixers were near 0‰. Foliar 15N in the native tree Metrosideros polymorpha did not vary with elevation (from sea level to tree-line), but it did increase

Peter M. Vitousek; Georgia Shearer; Daniel H. Kohl

1989-01-01

257

Impact of foliar herbivory on the development of a root-feeding insect and its parasitoid  

Microsoft Academic Search

The majority of studies exploring interactions between above- and below-ground biota have been focused on the effects of root-associated\\u000a organisms on foliar herbivorous insects. This study examined the effects of foliar herbivory by Pieris brassicae L. (Lepidoptera: Pieridae) on the performance of the root herbivore Delia radicum L. (Diptera: Anthomyiidae) and its parasitoid Trybliographa rapae (Westwood) (Hymenoptera: Figitidae), mediated through

Roxina Soler; T. Martijn Bezemer; Anne Marie Cortesero; Wim H. Van der Putten; Louise E. M. Vet; Jeffrey A. Harvey

2007-01-01

258

Foliar water uptake: a common water acquisition strategy for plants of the redwood forest  

Microsoft Academic Search

Evaluations of plant water use in ecosystems around the world reveal a shared capacity by many different species to absorb\\u000a rain, dew, or fog water directly into their leaves or plant crowns. This mode of water uptake provides an important water\\u000a subsidy that relieves foliar water stress. Our study provides the first comparative evaluation of foliar uptake capacity among\\u000a the

Emily Burns Limm; Kevin A. Simonin; Aron G. Bothman; Todd E. Dawson

2009-01-01

259

Remote Assessment of Forest Health in Southern Arizona, USA: Evidence for Ozone-Induced Foliar Injury  

Microsoft Academic Search

This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona\\u000a from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent\\u000a moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone\\u000a exposure levels (SUM60 and W126) increased from

JEREMY E. DIEM

2002-01-01

260

Foliar respiration in an old-growth Pseudotsuga-Tsuga forest  

Microsoft Academic Search

Old-growth forest ecosystems accrue carbon at small mean rates and may function as carbon sinks in some years and as carbon sources in others. Foliar respiration is a large component of stand carbon balance and could be variable enough to substantially affect source-sink behaviors. However, foliar respiration has not been well studied in old-growth canopies. We examined seasonal, interannual, spatial,

Clifton E. Cooper; Sean C. Thomas; William E. Winner

2006-01-01

261

Foliar Nitrogen Uptake from Wet Deposition and the Relation with Leaf Wettability and Water Storage Capacity  

Microsoft Academic Search

This study assessed the foliar uptake of 15N-labelled nitrogen (N) originating from wet deposition along with leaf surface conditions, measured by wettability and water\\u000a storage capacity. Foliar 15N uptake was measured on saplings of silver birch, European beech, pedunculate oak and Scots pine and the effect of nitrogen\\u000a form (NH4+ or NO3?), NH4+ to NO3? ratio and leaf phenology on

Sandy Adriaenssens; Jeroen Staelens; Karen Wuyts; An de Schrijver; Shari Van Wittenberghe; Tatiana Wuytack; Fatemeh Kardel; Kris Verheyen; Roeland Samson; Pascal Boeckx

2011-01-01

262

Calcium absorption and achlorhydria  

Microsoft Academic Search

Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium

Robert R. Recker

1985-01-01

263

Calcium Compartments in Brain  

Microsoft Academic Search

Excellent progress has been made toward understanding the physiology and pharmacology of specific calcium-related cellular processes of the brain, but few studies have provided an integrated view of brain calcium kinetics. To further the knowledge of the size and binding properties of brain calcium compartments, the authors have conducted a series of experiments in hippocampal brain slices exposed to high

George C. Newman; Frank E. Hospod; Clifford S. Patlak; Sean D. Trowbridge; Richard J. Wilke; Mark Fuhrmann; Keith W. Jones

2002-01-01

264

Calcium Secretion into Milk  

Microsoft Academic Search

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

Margaret C. Neville

2005-01-01

265

Secondary calcium solid electrolyte high temperature battery  

Microsoft Academic Search

The application of polycrystalline Ca(2+) conducting beta-double prime alumina solid electrolytes to a new type of high temperature battery is investigated, experimentally. The negative electrode in the battery consisted of a calcium-silicon alloy whose redox electrochemistry was mediated by the solid electrolyte via molten salt eutectic CaCl2 (51.4 m\\/o), and CaI2 (mp 550 C). The molten salt and the calcium

A. F. Sammells; B. Schumacher

1986-01-01

266

Stoichiometric patterns in foliar nutrient resorption across multiple scales  

USGS Publications Warehouse

*Nutrient resorption is a fundamental process through which plants withdraw nutrients from leaves before abscission. Nutrient resorption patterns have the potential to reflect gradients in plant nutrient limitation and to affect a suite of terrestrial ecosystem functions. *Here, we used a stoichiometric approach to assess patterns in foliar resorption at a variety of scales, specifically exploring how N : P resorption ratios relate to presumed variation in N and/or P limitation and possible relationships between N : P resorption ratios and soil nutrient availability. *N : P resorption ratios varied significantly at the global scale, increasing with latitude and decreasing with mean annual temperature and precipitation. In general, tropical sites (absolute latitudes < 23°26?) had N : P resorption ratios of < 1, and plants growing on highly weathered tropical soils maintained the lowest N : P resorption ratios. Resorption ratios also varied with forest age along an Amazonian forest regeneration chronosequence and among species in a diverse Costa Rican rain forest. *These results suggest that variations in N : P resorption stoichiometry offer insight into nutrient cycling and limitation at a variety of spatial scales, complementing other metrics of plant nutrient biogeochemistry. The extent to which the stoichiometric flexibility of resorption will help regulate terrestrial responses to global change merits further investigation.

Reed, Sasha C.; Townsend, Alan R.; Davidson, Eric A.; Cleveland, Cory C.

2012-01-01

267

Characterization of polyketide metabolites from foliar endophytes of Picea glauca.  

PubMed

A collection of 250 foliar endophytes of Picea glauca (white spruce) yielded several isolates that produced metabolites toxic to Choristoneura fumiferana (spruce budworm). Three of these strains were selected for further study based on their ability to be cultured and produce secondary metabolites under laboratory conditions. The culture filtrate of each was extracted and analyzed by LC-MS and LC-NMR, and the major metabolites were isolated and characterized. Structures were elucidated by spectroscopic analyses including 2D NMR and HRMS and by comparison to literature data. In some cases the extract was methylated in order to facilitate separation, but the original natural structure was determined by comparing the NMR data of the isolated methylated product with that of the stop-flow NMR of the underivatized extract (i.e., 2a, 2b, and 4). Two of these metabolites, 1 and 2a, are new structures, 3 and 4 are reported here for the first time as fungal metabolites, and 5- 10 as known fungal metabolites from other species. Tyrosol (10) was the only common metabolite found in all three extracts but did not account for the observed toxicity to C. fumiferana. PMID:18636777

Sumarah, Mark W; Puniani, Eva; Blackwell, Barbara A; Miller, J David

2008-07-18

268

Plant homeostasis of foliar manganese sinks: specific variation in hyperaccumulators.  

PubMed

Plant manganese (Mn) hyperaccumulation provides unusual insight into homeostasis of this essential micronutrient, in particular its excessive storage in shoot tissues. The compartmentation of hyperaccumulated foliar Mn appears exceptional among metal hyperaccumulators, since it occurs via specific microdistribution patterns. Here, three associated Mn hyperaccumulators, Virotia neurophylla, Maytenus fournieri, and Garcinia amplexicaulis exhibiting distinctly different Mn detoxification strategies were examined. Non-invasive sample preparation in conjunction with cryo scanning electron microscopy (SEM) was used to obtain in vivo quantitative microprobe X-ray and anatomical data from fully hydrated cells. Highly vacuolated large palisade mesophyll cells in V. neurophylla leaves were found to contain around 650 mM Mn. The large non-photosynthetic hypodermal cells of M. fournieri leaves, also with high vacuolar content, and the main site for Mn disposal, had an estimated mean vacuolar Mn concentration of around 600 mM. Previous qualitative X-ray mapping had shown Mn to be almost evenly sequestered across the entire leaf cross section of G. amplexicaulis. However, quantitative data obtained here showed a marked variation in localised concentrations that ranged between ~15 and >800 mM. Notable among these were mean values of >600 mM in spongy mesophyll cells, and ~800 mM within cells of a narrow sub epidermal layer preceding the palisade mesophyll. This study demonstrated the extraordinary Mn carrying capacities of different types of leaf cell vacuoles. PMID:22772585

Fernando, Denise R; Woodrow, Ian E; Baker, Alan J M; Marshall, Alan T

2012-07-07

269

Foliar Uptake of Atmospheric Reactive Nitrogen Pollution Along an Urban-Rural Gradient in New York State  

NASA Astrophysics Data System (ADS)

Vegetation is an important sink for atmospheric reactive nitrogen (N) pollution in terrestrial ecosystems, and when soil N is limiting, foliar N uptake can be a source of plant-available N. A proxy for pollution derived N, and in particular foliar assimilated N, would be useful to quantify the impact of the foliar uptake pathway on plant metabolism. Nitrogen stable isotope ratios (15N/14N) are practical for this purpose because forms of plant-available N often have varying isotopic compositions. However, the mechanisms driving differences in foliar N isotopic composition (?15N) are still unresolved. Current understanding of foliar ? 15N suggests these values primarily represent the integration of the soil water solution ?15N, direct foliar uptake of atmospheric reactive N, within-plant fractionations, and fractionation due to the fungus to root transfer in mycorrhizae. In this study, we investigated the influence of direct foliar uptake, soil solution ? 15N, and mycorrhizae on foliar ?15N in seedlings of two dominant Northeastern tree species, red maple (Acer rubrum) and red oak (Quercus rubra), along an N deposition gradient in New York State. Using a potted plant mesocosm system, we compared foliar ?15N values directly to soil solution ?15N values while controlling for mycorrhizal associations. Both species showed higher foliar ?15N when exposed to fractionation by mycorrhizal associations. Overall, A. rubrum showed higher foliar ?15N than Q. rubra across all sites. In both species, patterns of foliar ?15N values were coupled with soil solution ?15N values across the N deposition gradient. Additionally, increasing atmospheric N deposition was correlated with higher foliar ?15N values in Q. rubra, but not in A. rubrum. Using a mixing model, we estimated that Q. rubra seedlings incorporated up to 7% of their assimilated N via direct foliar uptake of atmospheric N pollution. However, foliar uptake was not detectable in A. rubrum seedlings. Results suggest that the use of foliar ?15N values may be an effective tool to estimate the magnitude of foliar uptake of pollutant N compounds under some circumstances.

Vallano, D.; Sparks, J. P.

2008-12-01

270

Potentiation of fractional sarcoplasmic reticulum calcium release by total and free intra-sarcoplasmic reticulum calcium concentration.  

PubMed Central

Our aim was to measure the influence of sarcoplasmic reticulum (SR) calcium content ([Ca](SRT)) and free SR [Ca] ([Ca](SR)) on the fraction of SR calcium released during voltage clamp steps in isolated rabbit ventricular myocytes. [Ca](SRT), as measured by caffeine application, was progressively increased by conditioning pulses. Sodium was absent in both the intracellular and in the extracellular solutions to block sodium/calcium exchange. Total cytosolic calcium flux during the transient was inferred from I(Ca), [Ca](SRT), [Ca](i), and cellular buffering characteristics. Fluxes via the calcium current (I(Ca)), the SR calcium pump, and passive leak from the SR were evaluated to determine SR calcium release flux (J(rel)). Excitation-contraction (EC) coupling was characterized with respect to both gain (integral J(rel)/integral I(Ca)) and fractional SR calcium release. Both parameters were virtually zero for a small, but measurable [Ca](SRT). Gain and fractional SR calcium release increased steeply and nonlinearly with both [Ca](SRT) and [Ca](SR). We conclude that potentiation of EC coupling can be correlated with both [Ca](SRT) and [Ca](SR). While fractional SR calcium release was not linearly dependent upon [Ca](SR), intra-SR calcium may play a crucial role in regulating the SR calcium release process.

Shannon, T R; Ginsburg, K S; Bers, D M

2000-01-01

271

Anodic Behavior of Alloy 22 in Calcium Chloride and in Calcium Chloride Plus Calcium Nitrate Brines  

Microsoft Academic Search

Alloy 22 (UNS N60622) is a nickel-based alloy, which is extensively used in aggressive industrial applications, especially due to its resistance to localized corrosion and stress corrosion cracking in high chloride environments. The purpose of this work was to characterize the anodic behavior of Alloy 22 in concentrated calcium chloride (CaCl) brines and to evaluate the inhibitive effect of nitrate,

K J Evans; S D Day; G O Ilevbare; M T Whalen; K J King; G A Hust; L L Wong; J C Estill; R B Rebak

2003-01-01

272

Calcium supplementation: cardiovascular risk?  

PubMed

Adequate dietary calcium intake and appropriate sunlight exposure ensuring adequate vitamin D availability are basic measures for the prevention of osteoporosis. Calcium and vitamin D supplementation increases bone density. Vitamin D plus calcium supplementation prevents hip fractures and other nonvertebral fractures in institutionalised persons 70 years of age or older. A meta-analysis of clinical trials showed an increase in myocardial infarction in patients taking calcium supplementation alone, with a relative risk of about 1.3. Epidemiological studies have not shown an increase in the cardiovascular risk. Conflicting results have also been reported in postmenopausal women taking both calcium and vitamin D. In an epidemiological study, hypercalcaemia was associated with increased mortality, particularly cardiovascular mortality. In practice, caution dictates that not all patients should routinely take calcium and vitamin D supplements. When calcium supplements are nonetheless used, the dose should be adjusted to dietary intake in order to avoid hypercalcaemia. PMID:23866352

2013-06-01

273

Effect of a plant growth regulator prohexadione-calcium on insect pests of apple and pear.  

PubMed

The effect of prohexadione-calcium, a plant growth regulator that inhibits gibberellin metabolism, on Cacopsylla pyricoloa (Foerster) in pear trees, and Choristoneura rosaceana (Harris) and Aphis spireacola Patch, in apple trees was studied. C. pyricoloa and A. spireacola populations were significantly reduced in prohexadione-calcium-treated pear and apple, respectively. Insecticide control of both pests with imidacloprid was synergized in treatments with prohexadione-calcium. In apples treated with prohexadione-calcium, there was a significant reduction in the number of C. rosaceana shelters per tree and amount of fruit injury at harvest attributable to the C. rosaceana. There was an additive effect when tebufenozide was used to control C. rosaceana in trees treated with prohexadione-calcium. Prohexadione-calcium significantly reduced vegetative growth in both pears and apples. Synergistic and additive treatment effects of prohexadione-calcium and pesticides used in this study may be due to better penetration and coverage of pesticides due to reduced foliar growth or to changes in the nutritional quality of the host plants. PMID:15889734

Paulson, G S; Hull, L A; Biddinger, D J

2005-04-01

274

Foliar herbivory and leaf traits of five native tree species in a young plantation of Central Panama  

Microsoft Academic Search

This study examined foliar herbivory on 1 year-old tree saplings planted in previously abandoned fields in central Panama.\\u000a Plots (15 × 15 trees) of Anacardium excelsum (Anacardiaceae), Dalbergia retusa (Fabaceae), Pachira quinata (Malvaceae), Tabebuia rosea (Bignoniaceae), and Terminalia amazonia (Combretaceae) were tested for herbivory using leaf counts and digital image analysis. Values of foliar carbon, foliar nitrogen,\\u000a specific leaf area (SLA), and leaf

Gillian S. Paul; Florencia Montagnini; Graeme P. Berlyn; Dylan J. Craven; Michiel van Breugel; Jefferson S. Hall

275

Chemical treatment of TiO 2-based coatings formed by plasma electrolytic oxidation in electrolyte containing nano-HA, calcium salts and phosphates for biomedical applications  

Microsoft Academic Search

TiO2-based coatings were formed on titanium alloy by plasma electrolytic oxidation (PEO) in an electrolyte containing nano-HA, calcium salts and phosphates. Bioactive surface was formed after chemical treatment (NaOH aqueous solution) of the PEO coating. The surface of the PEO coating was mainly composed of Ti, O, Ca and P showing anatase and rutile; while that of the chemically treated

Daqing Wei; Yu Zhou; Dechang Jia; Yaming Wang

2008-01-01

276

Preparation of a novel fluorescence nanosensor based on calcein-doped silica nanoparticles, and its application to the determination of calcium in blood serum  

Microsoft Academic Search

.  A fluorescent nanosensor based on the use of calcein-doped silica nanoparticles (CDSNPs) for the determination of calcium\\u000a in blood serum is detailed. Calcein is entrapped within silica nanoparticles by the inverse microemulsion polymerisation process\\u000a that produces spherical sensors in the size region of 48 ± 4?nm. Calcein encapsulation reduces calcein leaching from the silica\\u000a matrix when immersed in water and

Xu Hun; Zhujun Zhang

2007-01-01

277

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

Microsoft Academic Search

Four high-calcium coal combustion by-products (two pulverized coal fly ashes (PCFA), a flue gas desulfurization (FGD) residue, and an atmospheric fluidized bed combustion (AFBC) fly ash), were tested for engineering properties and ability to immobilize boron and selenium. These data are needed to explore high-volume utilization in engineered structures or in solidification\\/stabilization (S\\/S) technology. Strengths of cured pastes (91 days),

B. Docktor; K. E. Eylands; J. S. Thompson; D. J. Hassett

1995-01-01

278

Impact of foliar herbivory on the development of a root-feeding insect and its parasitoid  

PubMed Central

The majority of studies exploring interactions between above- and below-ground biota have been focused on the effects of root-associated organisms on foliar herbivorous insects. This study examined the effects of foliar herbivory by Pieris brassicae L. (Lepidoptera: Pieridae) on the performance of the root herbivore Delia radicum L. (Diptera: Anthomyiidae) and its parasitoid Trybliographa rapae (Westwood) (Hymenoptera: Figitidae), mediated through a shared host plant Brassica nigra L. (Brassicaceae). In the presence of foliar herbivory, the survival of D. radicum and T. rapae decreased significantly by more than 50%. In addition, newly emerged adults of both root herbivores and parasitoids were significantly smaller on plants that had been exposed to foliar herbivory than on control plants. To determine what factor(s) may have accounted for the observed results, we examined the effects of foliar herbivory on root quantity and quality. No significant differences in root biomass were found between plants with and without shoot herbivore damage. Moreover, concentrations of nitrogen in root tissues were also unaffected by shoot damage by P. brassicae larvae. However, higher levels of indole glucosinolates were measured in roots of plants exposed to foliar herbivory, suggesting that the development of the root herbivore and its parasitoid may be, at least partly, negatively affected by increased levels of these allelochemicals in root tissues. Our results show that foliar herbivores can affect the development not only of root-feeding insects but also their natural enemies. We argue that such indirect interactions between above- and below-ground biota may play an important role in the structuring and functioning of communities.

Bezemer, T. Martijn; Cortesero, Anne Marie; Van der Putten, Wim H.; Vet, Louise E. M.; Harvey, Jeffrey A.

2007-01-01

279

Application of Low-Frequency Alternating Current Electric Fields Via Interdigitated Electrodes: Effects on Cellular Viability, Cytoplasmic Calcium, and Osteogenic Differentiation of Human Adipose-Derived Stem Cells  

PubMed Central

Electric stimulation is known to initiate signaling pathways and provides a technique to enhance osteogenic differentiation of stem and/or progenitor cells. There are a variety of in vitro stimulation devices to apply electric fields to such cells. Herein, we describe and highlight the use of interdigitated electrodes to characterize signaling pathways and the effect of electric fields on the proliferation and osteogenic differentiation of human adipose-derived stem cells (hASCs). The advantage of the interdigitated electrode configuration is that cells can be easily imaged during short-term (acute) stimulation, and this identical configuration can be utilized for long-term (chronic) studies. Acute exposure of hASCs to alternating current (AC) sinusoidal electric fields of 1?Hz induced a dose-dependent increase in cytoplasmic calcium in response to electric field magnitude, as observed by fluorescence microscopy. hASCs that were chronically exposed to AC electric field treatment of 1?V/cm (4?h/day for 14 days, cultured in the osteogenic differentiation medium containing dexamethasone, ascorbic acid, and ?-glycerol phosphate) displayed a significant increase in mineral deposition relative to unstimulated controls. This is the first study to evaluate the effects of sinusoidal AC electric fields on hASCs and to demonstrate that acute and chronic electric field exposure can significantly increase intracellular calcium signaling and the deposition of accreted calcium under osteogenic stimulation, respectively.

McCullen, Seth D.; McQuilling, John P.; Grossfeld, Robert M.; Lubischer, Jane L.; Clarke, Laura I.

2010-01-01

280

Calcium-induced calcium release in neurones  

Microsoft Academic Search

Neurones express several subtypes of intracellular Ca2+ channels, which are regulated by cytoplasmic calcium concentration ([Ca2+]c) and provide the pathway for Ca2+-induced Ca2+ release (CICR) from endoplasmic reticulum Ca2+ stores. The initial studies of CICR which employed several pharmacological tools (and in particular caffeine and ryanodine) demonstrated that: (i) caffeine induces intracellular calcium release in various peripheral and central neurones;

A. Verkhratsky; A. Shmigol

1996-01-01

281

Precision and accuracy of visual foliar injury assessments  

SciTech Connect

The study compared three measures of foliar injury: (i) mean percent leaf area injured of all leaves on the plant, (ii) mean percent leaf area injured of the three most injured leaves, and (iii) the proportion of injured leaves to total number of leaves. For the first measure, the variation caused by reader biases and day-to-day variations were compared with the innate plant-to-plant variation. Bean (Phaseolus vulgaris 'Pinto'), pea (Pisum sativum 'Little Marvel'), radish (Rhaphanus sativus 'Cherry Belle'), and spinach (Spinacia oleracea 'Northland') plants were exposed to either 3 ..mu..L L/sup -1/ SO/sub 2/ or 0.3 ..mu..L L/sup -1/ ozone for 2 h. Three leaf readers visually assessed the percent injury on every leaf of each plant while a fourth reader used a transparent grid to make an unbiased assessment for each plant. The mean leaf area injured of the three most injured leaves was highly correlated with all leaves on the plant only if the three most injured leaves were <100% injured. The proportion of leaves injured was not highly correlated with percent leaf area injured of all leaves on the plant for any species in this study. The largest source of variation in visual assessments was plant-to-plant variation, which ranged from 44 to 97% of the total variance, followed by variation among readers (0-32% of the variance). Except for radish exposed to ozone, the day-to-day variation accounted for <18% of the total. Reader bias in assessment of ozone injury was significant but could be adjusted for each reader by a simple linear regression (R/sup 2/ = 0.89-0.91) of the visual assessments against the grid assessments.

Gumpertz, M.L. (Northrop Services Inc., Corvallis, OR); Tingey, D.T.; Hogsett, W.E.

1982-07-01

282

The impact of thiamethoxam on bumble bee broods ( Bombus terrestris L.) following drip application in covered tomato crops  

Microsoft Academic Search

The side effects of the neonicotinyl compound thiamethoxam on the brood of bumble bees (Bombus terrestris L.) were investigated on tomatoes in plastic tunnels and glasshouses.Preceeding trials had revealed a strong contact and stomach activity of the compound by foliar application. A decisive improvement was obtained by replacing the foliar by drip irrigation of thiamethoxam at rates between 150 and

B. Sechser; J. Freuler

2003-01-01

283

Calcium activation of frog slow muscle fibres  

PubMed Central

1. Skinned muscle fibres were prepared from the tonus bundle of the frog iliofibularis muscle and the contractile response elicited by applied calcium ions was studied. The fibre type was determined by electron microscopy. 2. Fast fibres shortened many times more rapidly than slow fibres, indicating that the slow contraction of slow fibres is an inherent property of the contractile mechanism. 3. The extent of spread of contraction following local calcium application was much greater in slow than in fast fibres, a difference which is consistent with the relative sparsity of the sarcoplasmic reticulum in slow fibres. 4. The ability of the sarcoplasmic reticulum of slow fibres to accumulate calcium was demonstrated by the in situ immobilization of calcium when oxalate solutions were added to the skinned fibre. ImagesPlate 1Plate 2Plate 3Plate 4Plate 5AB

Costantin, L. L.; Podolsky, R. J.; Tice, Lois W.

1967-01-01

284

Hyperuricosuric calcium nephrolithiasis.  

PubMed

Since the findings of Yü and Gutman [1], the hyperuricosuric calcium stone former is a unique clinical entity. While an impressive number of clinical and epidemiologic studies implicate hyperuricosuria in calcium stone formation, the exact physicochemical mechanism by which uric acid affects calcium oxalate crystallization has not been proven. Allopurinol decreases stone recurrences and is the drug of choice for patients with isolated HCN. PMID:12474638

Sorensen, Carsten M; Chandhoke, Paramjit S

2002-12-01

285

The Calcium Economy  

Microsoft Academic Search

Calcium is the fifth most abundant element in the biosphere (after iron, aluminum, silicon, and oxygen). It is the stuff of\\u000a limestone and marble, coral and pearls, seashells and eggshells, antlers and bones. Because calcium salts exhibit intermediate\\u000a solubility, calcium is found both in solid form (rocks) and in solution. It was probably present in abundance in the watery\\u000a environment

Robert P. Heaney

286

Calcium and retinal function  

Microsoft Academic Search

We survey the primary roles of calcium in retinal function, including photoreceptor transduction, transmitter release by different\\u000a classes of retinal neuron, calcium-mediated regulation of gap-junctional conductance, activation of certain voltage-gated\\u000a channels for K+ and C1?, and modulation of postsynaptic potentials in retinal ganglion cells. We discuss three mechanisms for changing [Ca2+]i, which include flux through voltage-gated calcium channels, through ligand-gated

Abram Akopian; Paul Witkovsky

2002-01-01

287

Idiopathic Calcium Nephrolithiasis  

Microsoft Academic Search

Calcium nephrolithiasis (CaNL) accounts for more than 70% of all renal stones, and its prevalence has increased in the last decades. Under this definition are included patients passing stones, composed of calcium oxalates and\\/or calcium phosphates. Current views of the pathogenesis of CaNL are based on the role of metabolic abnormalities which concur to render urines more conducive to crystallization.

Martino Marangella; Corrado Vitale; Cristiana Bagnis; Michele Bruno; Adriano Ramello

1999-01-01

288

Nutrient leaching from conifer needles in relation to foliar apoplast cation-exchange capacity  

SciTech Connect

Limited evidence to date suggests that acidic precipitation promotes leaching of nutrient cations from conifer foliage. In order to evaluate the relative contribution of the apoplast cation exchange complex and symplast nutrient pools to the leached ions, the magnitude of potential foliar leaching in response to acidic precipitation was compared to foliar apoplast cation exchange capacity (CEC) for two conifer tree species (Pseudotsuga menziesii and Picea engelmanii). Leaching increased with decreasing pH and increasing time of immersion. At pH 2.1 and 3.1, equivalents of H+ depleted from the acidic solutions approximated equivalent of cations gained by the solutions. Maximum amounts leached were less than 40 micro equiv/g dry weight of needles for all ions combined. Measured foliar apoplast CEC for these species was approximately 120 micro equiv/g dry weight of needles. These relative magnitudes indicated that the apoplast provided the leached ions.

Turner, D.P.; van Broekhuizen, H.J.

1992-01-01

289

The role of the sodium-calcium exchanger for calcium extrusion in coronary arteries  

Microsoft Academic Search

Calcium ionophores, such as the A23187, cause endothelium-dependent relaxation of arterial strips with intact endothelium, whereas the effect of the ionophore should result from the combination of a relaxation caused by the endothelium-dependent factors and of a contraction of the smooth muscles. In addition, the application of a calcium ionophore to a strip of pig coronary arteries without endothelium does

Stéphane Budel; Jean-Louis Beny

2000-01-01

290

Application of the Molecular Interaction Volume Model (MIVM) to Calcium-Based Liquid Alloys of Systems Forming High-Melting Intermetallics.  

PubMed

The thermodynamic properties of multiple liquid alloys with strong negative deviation from ideality were successfully modeled by the molecular interaction volume model (MIVM). The modeled partial Gibbs free energy of calcium in Ca-Ag, Ca-In, Ca-Pb, Ca-Sn, Ca-Tl, and Ca-Zn at 800 °C was within 1.5 kJ/mol of the existing experimental data. The partial Gibbs free energy of calcium in Ca-Bi liquid alloys at 600 °C was predicted within 1.6 kJ/mol (or 1%) by the MIVM from experimental data at 800 °C. For the first time, the MIVM was applied to a ternary system far from ideality, Ca-Sb-Pb. The partial Gibbs free energy of Ca in six Ca-Pb-Sb alloys was determined by emf measurements in a cell configured as Ca(s)|CaF2(s)|Ca-Sb-Pb, over the temperature range of 500-830 °C. These values were 2% (or 5 kJ/mol) more negative than those predicted by the MIVM using experimental data for the Ca-Pb, Ca-Sb, and Pb-Sb binary alloys. This difference was attributed to the inability of the MIVM to account for interactions between the first nearest neighbors of Ca, Pb and Sb in the ternary Ca-Sb-Pb alloy. PMID:23621449

Poizeau, Sophie; Sadoway, Donald R

2013-05-24

291

EVALUATION OF CALCIUM SENSORS IN FRESH AND SALTWATER  

EPA Science Inventory

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

292

Eleven-year response of foliar chemistry to chronic nitrogen and sulfur additions at the Bear Brooks Watershed in Maine  

SciTech Connect

The foliar chemistry of sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since 1989 with ammonium sulfate ((NH4)2SO4) at a rate of 25.2 kg N·ha–1·year–1. Foliar N concentrations were higher in all tree species within the treated watershed compared with trees within the reference watershed. Foliar Ca and Mg concentrations were lower in American beech and red spruce within the treated watershed. There were no significant differences in foliar K concentrations between watersheds. Foliar P and Mn concentration differences between watersheds were inconsistent among years. Differences in foliar N concentrations between watersheds declined over time in sugar maple but not in red spruce or American beech. Differences in foliar Ca and Mg concentrations between the treated and reference watersheds increased over time for American beech and red spruce, primarily because of a consistent decline in concentrations of these nutrients in trees within the treated watershed. No temporal trends in foliar Ca and Mg concentration differences between watersheds were observed for sugar maple.

Jose Alexander Elvir; Gregory J. White

2005-06-01

293

Foliar injury, tree growth and mortality, and lichen studies in Mammoth Cave National Park. Final report, 1985-1986  

Microsoft Academic Search

Foliar condition, tree growth, tree mortality, and lichen communities were studied in Mammoth Cave National Park, Kentucky, to document the present forest condition and to provide a basis for detecting future changes. Foliar injury by ozone was common on many plant species in 1985. Species showing the most injury were white ash, green ash, redbud, sycamore, tulip poplar, milkweed, and

B. McCune; C. L. Cloonan; T. V. Armentano

1987-01-01

294

REMOTE SENSING OF FOLIAR MASS AND CHLOROPHYLL AS INDICATORS OF FOREST HEALTH: PRELIMINARY RESULTS FROM A PROJECT IN NORWAY  

Microsoft Academic Search

ABSTRACT Variations in foliar mass ,and chlorophyll concentration are ,likely to reflect temporal variation in forest health well, by capturing both defoliation and discoloration symptoms. Canopy chlorophyll mass is the product of foliar mass and chlorophyll concentration. In the current project, we try to model these two variables using airborne LiDAR and hyper-spectral data, respectively. On ground we have data

S. Solberg; E. Næsset; L. Aurdal; H. Lange; O. m. Bollandsås; R. Solberg

295

Calcium and bones  

MedlinePLUS

... mineral that is important for making healthy bones. (Phosphorous is another important mineral for healthy bones.) Calcium cannot be made by the body. The body gets the calcium it needs through the food you eat. If you do not get enough ...

296

Calcium signaling in neurodegeneration  

PubMed Central

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

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

2009-01-01

297

CALCIUM IMPROVES HATCHING SUCCESS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Research was conducted to determine the effect of removing supplemental calcium during 24-h developmental periods on channel catfish, Ictalurus punctatus, embryo survival. Low water calcium-hardness (< 10 mg/L as CaCO3) was found to have a dramatic negative effect (P < 0.05) on embryo survival duri...

298

Calcium Nutrition in Adolescence  

Microsoft Academic Search

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

Marta Mesías; Isabel Seiquer; M. Pilar Navarro

2011-01-01

299

1-dimensional calcium FORT  

NASA Astrophysics Data System (ADS)

We report efforts to trap calcium in a FORT. The FORT is created by focusing a 30 W argon laser to a 20 micron spot in a calcium MOT. The trap depth is calculated to be a few milliKelvin, a few times the Doppler temperature. The FORT should fill with metastable ^3P atoms, and evaporative cooling is expected to occur.

Daily, Jared; Cummings, Elizabeth; Durfee, Dallin; Bergeson, Scott

2004-05-01

300

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

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Calcium pantothenate, calcium chloride double salt. 172.330 Section 172... § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium...

2009-04-01

301

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

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Calcium pantothenate, calcium chloride double salt. 172.330 Section 172... § 172.330 Calcium pantothenate, calcium chloride double salt. The food additive calcium chloride double salt of calcium...

2010-01-01

302

Circadian Models of Serum Potassium, Sodium, and Calcium Concentrations in Healthy Individuals and Their Application to Cardiac Electrophysiology Simulations at Individual Level  

PubMed Central

In the article a brief description of the biological basis of the regulation of human biological clocks was presented in order to introduce the role of circadian rhythms in physiology and specifically in the pharmacological translational tools based on the computational physiology models to motivate the need to provide models of circadian fluctuation in plasma cations. The main aim of the study was to develop statistical models of the circadian rhythm of potassium, sodium, and calcium concentrations in plasma. The developed ion models were further tested by assessing their influence on QT duration (cardiac endpoint) as simulated by the biophysically detailed models of human left ventricular cardiomyocyte. The main results are model equations along with an electronic supplement to the article that contains a fully functional implementation of all models.

Fijorek, Kamil; Puskulluoglu, Miroslawa

2013-01-01

303

Surface properties of calcium phosphate particles for self setting bone cements  

Microsoft Academic Search

Calcium phosphate cements (CPC), consist of multicomponent powder mixtures of calcium orthophosphates with grain sizes in the region of 1–20 ?m. Due to the small particle sizes surface properties as the zeta potential and adsorption processes play a significant role during manufacturing and application. In the context of this work zeta potentials of different calcium phosphates, like dicalcium phosphate anhydride

U. Gbureck; J. Probst; R. Thull

2002-01-01

304

Constraints on Ca\\/Sr as a Proxy for Calcium in Forest Ecosystems  

Microsoft Academic Search

Calcium is a key plant nutrient and important base cation in ecosystems. Our current efforts to quantify Ca cycling in ecosystems rely on indirect proxies, e.g., Ca\\/Sr or Sr isotopic systems (1). An important assumption in these applications is that the elemental ratio of calcium to strontium faithfully represents calcium cycling and that little fractionation occurs through biogeochemical and physiological

C. J. Hoff; E. A. Hobbie; R. Hallett; J. Colpaert; J. G. Bryce

2004-01-01

305

Ultrathin calcium silicate hydrate nanosheets with large specific surface areas: synthesis, crystallization, layered self-assembly and applications as excellent adsorbents for drug, protein, and metal ions.  

PubMed

A simple and low-cost solution synthesis is reported for low-crystalline 1.4 nm tobermorite-like calcium silicate hydrate (CSH) ultrathin nanosheets with a thickness of ~2.8 nm and with a large specific surface area (SSA), via a reaction-rate-controlled precipitation process. The BET SSA of the CSH ultrathin nanosheets can reach as high as 505 m(2) g(-1) . The CSH ultrathin nanosheets have little cytotoxicity and can be converted to anhydrous calcium silicate (ACS) ultrathin nanosheets with a well preserved morphology via a heat treatment process. The crystallinity of CSH ultrathin nanosheets can be improved by solvothermal treatment in water/ethanol binary solvents or a single solvent of water, producing well-crystalline 1.1 nm tobermorite-like CSH nanobelts or nanosheets. CSH ultrathin nanosheets acting as building blocks can self-assemble into layered nanostructures via three different routes. The CSH ultrathin nanosheets are investigated as promising adsorbents for protein (hemoglobin, Hb), drug (ibuprofen, IBU), and metal ions (Cr(3+) , Ni(2+) , Cu(2+) , Zn(2+) , Cd(2+) , Pb(2+) ). The highest adsorbed percentages of Hb and IBU are found to be 83% and 94%, respectively. The highest adsorption capacities of Hb and IBU are found to be as high as 878 milligram Hb per gram CSH and 2.2 gram IBU per gram CSH, respectively. The ppm level metal ions can be totally adsorbed from aqueous solution in just a few minutes. Thus, the CSH ultrathin nanosheets are a promising candidate as excellent adsorbents in the biomedical field and for waste water treatment. Several empirical laws are summarized based on the adsorption profiles of Hb and IBU using CSH ultrathin nanosheets as the adsorbent. Furthermore, the ACS ultrathin nanosheets as adsorbents for Hb protein and IBU drug are investigated. PMID:23585365

Wu, Jin; Zhu, Ying-Jie; Chen, Feng

2013-04-15

306

21 CFR 184.1191 - Calcium carbonate.  

Code of Federal Regulations, 2013 CFR

...As a byproduct in the âLime soda processâ; (2) By precipitation of calcium carbonate from calcium hydroxide in the âCarbonation processâ; or (3) By precipitation of calcium carbonate from calcium chloride in the âCalcium...

2013-04-01

307

The processing, properties, and applications of calcium aluminate–phenol resin composite 1 1 This paper was originally submitted to Advanced Cement Based Materials on 15 October 1997 and accepted on 22 March 1998. The paper was received at the Editorial Office of Cement and Concrete Research on 20 August 1998 and accepted in final form on 14 September 1998  

Microsoft Academic Search

The processing, properties, and a few applications of calcium aluminate–phenol resin composite with very high flexural strength are discussed. This composite contains a very large amount of cement (70 vol%) but shows unusual engineering properties, which have not yet been achieved by traditional cement-based materials. The flexural strength of the composite is found to be 120 to 220 MPa; in

G. K. Dinilprem Pushpalal; Tadashi Kobayashi; Toshio Kawano; Naomi Maeda

1999-01-01

308

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

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

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

309

Vinylphosphonic acid-modified calcium aluminate and calcium silicate cements  

Microsoft Academic Search

Cementitious materials in terms of calcium phosphate cements (CPC) were prepared through the acid-base reaction between vinylphosphonic acid (VPA) and calcium aluminate cement (CAC) reactants or calcium silicate cement (CSC) reactants at 25 °C. Using CAC, two factors were responsible for the development of strength in the cements: one is the formation of an amorphous calcium-complexed vinylphosphonate (CCVP) salt phase

T. Sugama; R. N. Mora

1996-01-01

310

CORRELATION BETWEEN OZONE EXPOSURE AND VISIBLE FOLIAR INJURY IN PONDEROSA AND JEFFREY PINES. (R825433)  

EPA Science Inventory

Ozone exposure was related to ozone-induced visible foliar injury in ponderosa and Jeffrey pines growing on the western slopes of the Sierra Nevada Mountains of California. Measurements of ozone exposure, chlorotic mottle and fascicle retention were collected during the years ...

311

Isotopic study of post-anthesis foliar incorporation of sulphur and nitrogen in wheat  

Microsoft Academic Search

Nitrogen (N) and sulphur (S) supplies have a strong influence on the quality and quantity of wheat storage proteins, which play an important role in the bread-making process. In order to relate the incorporation and distribution of foliar N and S fertilisers at the post-anthesis stage to the quality of wheat, N and S isotopes were used as tracers. The

I. Tea; T. Genter; N. Naulet; E. Morvan; D. Kleiber

2003-01-01

312

Photochemical Transformation and Bacterial Utilization of Dissolved Organic Matter and Disinfection Byproduct Precursors from Foliar Litter  

Microsoft Academic Search

Foliar litter is an important terrestrial source of dissolved organic matter (DOM) in surface water. DOM is a public health concern since it is a precursor of carcinogenic disinfection byproducts (DBPs) during drinking water treatment. Chemical characterization of in-situ water samples for their impact on water treatment may be misleading because DOM characteristics can be altered from their original composition

A. T. Chow; P. Wong; A. T. O'Geen; R. A. Dahlgren

2009-01-01

313

Impact of the foliar pathogen Swiss needle cast on wood quality of Douglas-fir  

Microsoft Academic Search

Abstract: Many stands of Douglas-fir (Pseudotsuga,menziesii (Mirb.) Franco) near coastal areas of Oregon and Washington are heavily infected with the foliar pathogen causing Swiss needle cast (SNC) disease, and yet there is very little research on the resulting wood quality. Modulus of elasticity (MOE), modulus of rupture (MOR), microfibril angle (MFA), wood density, latewood proportion, and sapwood moisture content were

G. R. Johnson; Amy T. Grotta; Barbara L. Gartner; Geoff Downes

2005-01-01

314

DEFENDER: A HIGH-YIELDING, PROCESSING POTATO CULTIVAR WITH FOLIAR AND TUBER RESISTANCE TO LATE BLIGHT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Potato cultivar ‘Defender’ has resistance to both foliar and tuber infection by newer genotypes of Phytophthora infestans. Resistance was derived from its Polish parent, KSA195-90. Released in 2004, Defender is high yielding, white-skinned, and suitable for processing into frozen potato products di...

315

Effects of Foliar Herbivory on Male and Female Reproductive Traits of Wild Radish, Raphanus raphanistrum  

Microsoft Academic Search

Abstract. In this study, we examined how foliar herbivory affected the relative allo- cation to male and female reproductive traits in a hermaphroditic plant. In two experiments, one in the greenhouse and the other in a growth chamber, leaves of full sibling plants of the annual wild radish, Raphanus raphanistrum, received one of four damage treatments to leaves (0, 25%

Kari Lehtila; Sharon Y. Strauss

1999-01-01

316

DEFENDER: A HIGH-YIELDING, PROCESSING POTATO CULTIVAR WITH FOLIAR AND TUBER RESISTANCE TO LATE BLIGHT  

Technology Transfer Automated Retrieval System (TEKTRAN)

The potato cultivar ‘Defender’ is high-yielding, white-skinned, and notable for having foliar and tuber resistance to late blight infection caused by Phytophthora infestans (Mont.) de Bary. It was released in 2004 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washin...

317

HERITABILITY OF TOLERANCE TO EARLY FOLIAR DECLINE IN THREE AMERICAN PIMA COTTON POPULATIONS.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Early foliar decline (EFD) is a recurring problem of Pima cotton (Gossypium barbadense L.) in the San Joaquin Valley of California where it has been implicated in yield and fiber quality losses. Anecdotal evidence indicates that genetic variability for tolerance to EFD exists within Pima germplasm....

318

Foliar water uptake: a common water acquisition strategy for plants of the redwood forest.  

PubMed

Evaluations of plant water use in ecosystems around the world reveal a shared capacity by many different species to absorb rain, dew, or fog water directly into their leaves or plant crowns. This mode of water uptake provides an important water subsidy that relieves foliar water stress. Our study provides the first comparative evaluation of foliar uptake capacity among the dominant plant taxa from the coast redwood ecosystem of California where crown-wetting events by summertime fog frequently occur during an otherwise drought-prone season. Previous research demonstrated that the dominant overstory tree species, Sequoia sempervirens, takes up fog water by both its roots (via drip from the crown to the soil) and directly through its leaf surfaces. The present study adds to these early findings and shows that 80% of the dominant species from the redwood forest exhibit this foliar uptake water acquisition strategy. The plants studied include canopy trees, understory ferns, and shrubs. Our results also show that foliar uptake provides direct hydration to leaves, increasing leaf water content by 2-11%. In addition, 60% of redwood forest species investigated demonstrate nocturnal stomatal conductance to water vapor. Such findings indicate that even species unable to absorb water directly into their foliage may still receive indirect benefits from nocturnal leaf wetting through suppressed transpiration. For these species, leaf-wetting events enhance the efficacy of nighttime re-equilibration with available soil water and therefore also increase pre-dawn leaf water potentials. PMID:19585154

Limm, Emily Burns; Simonin, Kevin A; Bothman, Aron G; Dawson, Todd E

2009-07-08

319

Trends in Pinus ponderosa foliar pigment concentration due to chronic exposure of ozone and acid rain  

Microsoft Academic Search

To determine the effects of ozone and acid rain on mature Ponderosa pine trees, Lawrence Livermore National Lab. has collaborated with University of California Berkeley, University of California Davis, California State University Chico, and the US Forest Service at the latter's Chico Tree Improvement Center. Foliar tissue from mature grafted scions of Pinus ponderosa were exposed to two times ambient

L. Neuman; J. Houpis; P. Anderson

1991-01-01

320

Foliar plasticity of hybrid spruce in relation to crown position and stand age  

Microsoft Academic Search

This study examined the foliar response of putative hybrid Engelmann ? white ? Sitka spruce (Picea engelmannii Parry ? Picea glauca (Moench) Voss ? Picea sitchensis (Bong.) Carr) needles in relation to crown posi- tion and across three stages of development (15, 55, and 145 years). We focused on the morphological and anatomical response, and used physiological measures (photosynthesis and

A. D. Richardson; G. P. Berlyn; P. M. S. Ashton; R. Thadani; I. R. Cameron

2000-01-01

321

Ozone exposure thresholds and foliar injury on forest plants in Switzerland  

Microsoft Academic Search

Canton Ticino in southern Switzerland is exposed to some of the highest concentrations of tropospheric ozone in Europe. During recent field surveys in Canton Ticino, foliar symptoms identical to those caused by ozone have been documented on native tree and shrub species. In Europe, the critical ozone level for forest trees has been defined at an AOT40 of 10 ppm.h

D. VanderHeyden; J. Skelly; J. Innes; C. Hug; J. Zhang; W. Landolt; P. Bleuler

2001-01-01

322

Notas Científicas Controle químico de doenças foliares na cultura do arroz irrigado  

Microsoft Academic Search

Resumo - O objetivo deste trabalho foi avaliar a interferência das doenças foliares na produtividade de duas cultivares de arroz irrigado, bem como determinar a interação entre ingredientes ativos e momento de aplicação, para o controle de escaldadura e mancha-marrom. Foram utilizados: tiofanato metílico, tebuconazole, azoxystrobin e trifloxystrobin + propiconazole, aplicados em cinco épocas, às cultivares IRGA 417 e El

Alisson Celmer; Marcelo Gripa Madalosso; Mônica Paula Debortoli

323

The effects of foliar pubescence and nutrient enrichment on arthropod communities of Metrosideros polymorpha (Myrtaceae)  

Microsoft Academic Search

Nutrient resource availability and host-plant foliar pubescence both influence arthropod food webs, but multifactor studies are needed to under- stand their interdependence and relative importance. Arthropods were sampled by clipping foliage from Metrosideros polymorpha (Myrtaceae) trees of pubescent, glabrous, and intermediate leaf forms on fertilised and unfertilised plots. 2. Fertilisation decreased leaf mass per area (LMA) but did not change

DANIEL S. G RUNER; A NDREW; D. T AYLOR; E. F ORKNER

2005-01-01

324

Control of stripe rust of winter wheat with foliar fungicides, 2007  

Technology Transfer Automated Retrieval System (TEKTRAN)

A total of nine foliar fungicide treatments were tested for efficacy to control stripe rust on spring wheat at Pullman, Washington during the 2006-2007 growth season using a randomized completed block design experiment with non-treated plots as the experimental control. Susceptible winter wheat var...

325

Observation and Confirmation of Foliar Ozone Symptoms of Native Plant Species of Switzerland and Southern Spain  

Microsoft Academic Search

Tropospheric ozone is considered as the major pollutant of concern to the health and productivity of forests in the eastern United States and has more recently become of increasing concern within the forests of southern Europe. Recent observations have clearly demonstrated foliar injury symptoms to be occurring on many tree and native plant species within remote forested areas. Several plant

J. M. Skelly; J. L. Innes; J. E. Savage; K. R. Snyder; D. Vanderheyden; J. Zhang; M. J. Sanz

1999-01-01

326

Effect of surface seeding on foliar blight severity and wheat performance  

Microsoft Academic Search

Spot blotch, caused by Cochliobolus sativus, is a serious disease constraint to wheat (Triticum aestivum L.) yields under rice–wheat systems in the lowlands of South Asia. The surface seeding of wheat, which is becoming popular as a resource conserving technology on resource-poor farms, might provide a more conducive environment for early foliar blight development. During 2002 and 2003 wheat growing

B. N. Mahto; E. Duveiller; R. C. Sharma

2006-01-01

327

SPECIATION OF GAS-PHASE AND FINE PARTICLE EMISSIONS FROM BURNING OF FOLIAR FUELS: JOURNAL ARTICLE  

EPA Science Inventory

NRMRL-RTP-P- 620 Hays**, M.D., Geron*, C.D., Linna**, K.J., Smith*, N.D., and Schauer, J.J. Speciation of Gas-Phase and Fine Particle Emissions from Burning of Foliar Fuels. Submitted to: Environmental Science & Technology EPA/600/J-02/234, http://pubs.acs.org/journals/esthag/...

328

Calcium Signaling and Neurodegeneration  

PubMed Central

Neurodegenerative disorders, such as Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), Huntington’s disease (HD), and spinocerebellar ataxias (SCA) are very important both for fundamental science and for practical medicine. Despite extensive research into the causes of these diseases, clinical researchers have had very limited progress and, as of now, there is still no cure for any of these diseases. One of the main obstacles in the way of creating treatments for these disorders is the fact that their etiology and pathophysiology still remain unclear. This paper reviews results that support the so–called “calcium hypothesis of neurodegenerative diseases.” The calcium hypothesis states that the atrophic and degenerative processes in the neurons of AD, PD, ALS, HD, and SCA patients are accompanied by alterations in calcium homeostasis. Moreover, the calcium hypothesis states that this deregulation of calcium signaling is one of the early–stage and key processes in the pathogenesis of these diseases. Based on the results we reviewed, we conclude that the calcium channels and other proteins involved in the neuronal calcium signaling system are potential drug targets for AD, PD, ALS, HD, and SCA therapy.

2010-01-01

329

76 FR 51991 - Determination That PENTETATE CALCIUM TRISODIUM (Trisodium Calcium Diethylenetriaminepentaacetate...  

Federal Register 2010, 2011, 2012, 2013

...FDA-2010-P-0628] Determination That PENTETATE CALCIUM TRISODIUM (Trisodium Calcium Diethylenetriaminepentaacetate) Solution for...Administration (FDA) has determined that PENTETATE CALCIUM TRISODIUM (trisodium calcium...

2011-08-19

330

Modeling calcium waves in cardiac myocytes: importance of calcium diffusion  

PubMed Central

Under certain conditions, cardiac myocytes engage in a mode of calcium signaling in which calcium release from the sarcoplasmic reticulum (SR) to myoplasm occurs in self-propagating succession along the length of the cell. This event is called a calcium wave and is fundamentally a diffusion-reaction phenomenon. We present a simple, continuum mathematical model that simulates calcium waves. The framework features calcium diffusion within the SR and myoplasm, and dual modulation of ryanodine receptor (RyR) release channels by myoplasmic and SR calcium. The model is used to illustrate the effect of varying RyR permeability, sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) activity and calcium ion mobility in myoplasm and SR on wave velocity. The model successfully reproduces calcium waves using experimentally-derived variables. It also supports the proposal for wave propagation driven by the diffusive spread of myoplasmic calcium, and highlights the importance of SR calcium load on wave propagation.

Swietach, Pawel; Spitzer, Kenneth W; Vaughan-Jones, Richard D

2010-01-01

331

Teaching calcium-induced calcium release in cardiomyocytes using a classic paper by Fabiato  

NSDL National Science Digital Library

This teaching paper utilizes the materials presented by Dr. Fabiato in his review article entitled "Calcium-induced release of calcium from the cardiac sarcoplasmic reticulum." In the review, supporting evidence of calcium-induced calcium release (CICR) is presented. Data concerning potential objections to the CICR theory are discussed as well. In closing, technical issues associated with the skinned cell model are mentioned. Based on this review article, teaching and learning points are put forth in this article to highlight two concepts: 1) the regulatory mechanisms of CICR in cardiomyocytes and 2) the recognition of contradicting hypotheses and limitations in experimental design. The first concept is certainly an important one for physiology students. The second concept is universally applicable to researchers in all fields of science. It is thus the aim of this article to cultivate a rewarding teaching and learning experience for both instructors and students.

Willmann Liang (Nanyang Technological University Biological Sciences)

2007-11-09

332

Remote assessment of forest health in southern Arizona, USA: evidence for ozone-induced foliar injury.  

PubMed

This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone exposure levels (SUM60 and W126) increased from 1982 to 1998 and were significantly correlated (r = 0.49 and 0.53, alpha = 0.05) with annual population totals in the Tucson area. Extensive masking of satellite images from 1972, 1986, and 1992 resulted in two optimal change detection areas, with one site, TVWMica, exposed mostly to the Tucson air pollution plume, while the other site, EMica, was more protected from Tucson-derived pollution. An overall increase in VI from 1972 to 1992 at both sites appears to have been caused by an increase in moisture availability. Larger foliar injury values in 1985 were associated with a smaller increase in VI (i.e., a smaller increase in green leaf biomass) from 1972 to 1986. From 1972 to 1986 and from 1986 to 1992, VI values at TV/WMica increased at a slower rate compared to those at EMica. The reduced increase in "green-up" may have been caused partially by ozone-induced foliar injury and resulting decreases in green leaf biomass. However, these spatial differences in VI values may have also been caused by a number of other factors. Results nevertheless reveal the strong possibility of distinct, topographically based, spatial variations in ozone-induced foliar injury within the Rincons. PMID:11830767

Diem, Jeremy E

2002-03-01

333

Climatic limits on foliar growth during major droughts in the southwestern USA  

NASA Astrophysics Data System (ADS)

Pronounced droughts during the 1950s and 2000s in the American Southwest provide an opportunity to compare mesoscale ecosystem responses to anomalously dry conditions before and during the regional warming that started in the late 1970s. This year-round warming has produced fewer cool season freezes, losses in regional snowpack, an 8-10 day advance in spring onset, and hotter summers, all of which should affect vegetation differently across seasons and elevations. Here, we examine indices that represent climatic limits on foliar growth for both drought periods and evaluate these indices for areas that experienced tree mortality during the 2000s drought. Relative to the 1950s drought, warmer conditions during the 2000s drought decreased the occurrence of temperatures too low for foliar growth at lower elevations in winter and higher elevations in summer. Higher vapor pressure deficits (VPDs), largely driven by warmer temperatures in the more recent drought, were more limiting to foliar growth from spring through summer at lower and middle elevations. At many locations where tree mortality occurred during the 2000s drought, low-temperature constraints on foliar growth were extremely unlimiting, whereas VPD constraints were extremely limiting from early spring through late autumn. Our analysis shows that in physiographically complex regions such as the Southwest, seasonality and elevational gradients are important for understanding vegetative responses to warming. It also suggests that continued warming will both increase the degree to which VPD limits foliar growth during future droughts and expand its reach to higher elevations and other seasons.

Weiss, Jeremy L.; Betancourt, Julio L.; Overpeck, Jonathan T.

2012-09-01

334

Atmospheric change alters foliar quality of host trees and performance of two outbreak insect species.  

PubMed

This study examined the independent and interactive effects of elevated carbon dioxide (CO(2)) and ozone (O(3)) on the foliar quality of two deciduous trees species and the performance of two outbreak herbivore species. Trembling aspen (Populus tremuloides) and paper birch (Betula papyrifera) were grown at the Aspen FACE research site in northern Wisconsin, USA, under four combinations of ambient and elevated CO(2) and O(3). We measured the effects of elevated CO(2) and O(3) on aspen and birch phytochemistry and on gypsy moth (Lymantria dispar) and forest tent caterpillar (Malacosoma disstria) performance. Elevated CO(2) nominally affected foliar quality for both tree species. Elevated O(3) negatively affected aspen foliar quality, but only marginally influenced birch foliar quality. Elevated CO(2) slightly improved herbivore performance, while elevated O(3) decreased herbivore performance, and both responses were stronger on aspen than birch. Interestingly, elevated CO(2) largely offset decreased herbivore performance under elevated O(3). Nitrogen, lignin, and C:N were identified as having strong influences on herbivore performance when larvae were fed aspen, but no significant relationships were observed for insects fed birch. Our results support the notion that herbivore performance can be affected by atmospheric change through altered foliar quality, but how herbivores will respond will depend on interactions among CO(2), O(3), and tree species. An emergent finding from this study is that tree age and longevity of exposure to pollutants may influence the effects of elevated CO(2) and O(3) on plant-herbivore interactions, highlighting the need to continue long-term atmospheric change research. PMID:21971584

Couture, John J; Meehan, Timothy D; Lindroth, Richard L

2011-10-05

335

Climatic limits on foliar growth during major droughts in the Southwestern U.S.A.  

USGS Publications Warehouse

Pronounced droughts during the 1950s and 2000s in the Southwestern U.S.A. (SW) provide an opportunity to compare mesoscale ecosystem responses to anomalously dry conditions before and during the regional warming that started in the late 1970s. This year-round warming has produced fewer cool season freezes, losses in regional snowpack, an 8-10 day advance in spring onset, and hotter summers, all of which should affect vegetation differently across seasons and elevations. Here, we examine indices that represent climatic limits on foliar growth for both drought periods, and evaluate these indices for areas that experienced tree mortality during the 2000s drought. Relative to the 1950s drought, warmer conditions during the 2000s drought decreased the occurrence of temperatures too low for foliar growth at lower elevations in winter and higher elevations in summer. Higher vapor pressure deficits (VPDs) largely driven by warmer temperatures in the more recent drought were more limiting to foliar growth from spring through summer at lower and middle elevations. At many locations where tree mortality occurred during the 2000s drought, low-temperature constraints on foliar growth were extremely unlimiting, whereas VPD constraints were extremely limiting from early spring through late autumn. Our analysis shows that in physiographically complex regions like the SW, seasonality and elevational gradients are important for understanding vegetative responses to warming. It also suggests that continued warming will increase the degree to which VPD limits foliar growth during future droughts, and expand its reach to higher elevations and other seasons.

Weiss, Jeremy L.; Betancourt, Julio L.; Overpeck, Jonathan T.

2012-01-01

336

Hormonal Control of Calcium Homeostasis  

Microsoft Academic Search

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

Gregory R. Mundy; Theresa A. Guise

1999-01-01

337

Foliar amino acid accumulation as an indicator of ecosystem stress for first-year sugar maple seedlings  

SciTech Connect

Accumulation of certain plant foliar amino acids (arginine, glutamine, and proline) can be used as indicators of anthropogenic and natural stressors, such as atmospheric deposition and mineral nutritional imbalances, which result in decreased plant growth. In this study a number of factors were evaluated to assess the use of foliar amino acid accumulation as indicators of sugar maple seedling stress at two sugar maple dominated forests in Michigan. These factors were: (1) first-year sugar maple (Acer saccharum Marshall) seedling growth, (2) N and P nutrition, (3) soluble foliar and root total amino acid concentrations, and (4) concentrations of foliar arginine, glutamine, and proline. The most southern site (Wellston), which was exposed to high atmospheric deposition and had high available soil P and seedling foliar P, had greater seedling growth. Foliar glutamine, arginine, and proline were greater at the most northern site (Alberta), which received lesser amounts of atmospheric deposition, but also had lower levels of available soil phosphorus, seedling foliar phosphorus, less seedling growth, and greater canopy closure. These results suggest that since atmospheric deposition is high in nitrogen, even the low levels of deposition at Alberta may be interacting with ecological variables such as, available soil phosphorus, light, or moisture to result in NIP imbalances and consequently higher arginine and glutamine concentrations in seedling foliage. 37 refs., 4 figs., 3 tabs.

McLaughlin, J.W.; Reed, D.D.; Jurgensen, M.F. [Michigan Technological Univ., Houghton, MI (United States)] [and others

1994-01-01

338

The Fusarium virguliforme toxin FvTox1 causes foliar sudden death syndrome-like symptoms in soybean.  

PubMed

Fusarium virguliforme causes sudden death syndrome (SDS) in soybean. The pathogen has never been isolated from diseased foliar tissues; therefore, one or more toxins have been considered to cause foliar SDS development. Cell-free F. virguliforme culture filtrates containing a toxin causes foliar SDS in soybean. A low-molecular-weight protein of approximately 13.5 kDa (FvTox1), purified from F. virguliforme culture filtrates, produces foliar SDS-like symptoms in cut soybean seedlings. Anti-FvTox1 monoclonal antibodies raised against the purified FvTox1 were used in isolating the FvTox1 gene. In the presence of light, recombinant FvTox1 protein expressed in an insect cell line resulted in chlorosis and necrosis in soybean leaf disks that are typical foliar SDS symptoms. SDS-susceptible but not the SDS-resistant soybean lines were sensitive to the baculovirus-expressed toxin. The requirement of light for foliar SDS-like symptom development indicates that FvTox1 induces foliar SDS in soybean, most likely through production of free radicals by interrupting photosynthesis. PMID:21635141

Brar, Hargeet K; Swaminathan, Sivakumar; Bhattacharyya, Madan K

2011-10-01

339

Calcium phosphate cements comprising autologous bone  

US Patent & Trademark Office Database

Aspects of the invention include methods for producing flowable compositions, e.g. pastes, that set into calcium phosphate containing products, where the products include autologous bone. Aspects of the invention further include compositions produced by the methods, as well as kits for preparing the same. The subject methods and compositions produced thereby find use in a variety of applications, including hard tissue repair applications.

Constantz; Brent R. (Cupertino, CA)

2010-02-09

340

Calcium in diet  

MedlinePLUS

... to take calcium supplements . The Recommended Dietary Allowance (RDA) for vitamins reflects how much of each vitamin most people should get each day. The RDA for vitamins may be used to help create ...

341

Calcium channel blocker overdose  

MedlinePLUS

Salhanick SD. Calcium channel antagonists. In: Shannon MW, Borron SW, Burns MJ, eds. Haddad and Winchester's Clinical Management of Poisoning and Drug Overdose . 4th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap ...

342

Stoichiometry of Calcium Medicines  

ERIC Educational Resources Information Center

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

Pinto, Gabriel

2005-01-01

343

Calcium supplements: Practical considerations  

Microsoft Academic Search

The preferable source of calcium is a balanced diet, but medicinal supplements are sometimes necessary if patients are to reach desired intakes. A divided dose regimen (4×\\/d; i.e., with meals and at bedtime) results in substantially greater absorption of a supplement than does l×\\/d dosing. However, differences in chemical solubility between supplement preparations are of little importance, with calcium carbonate

R. P. Heaney

1991-01-01

344

Calcium Bioavailability and Kinetics of Calcium Ascorbate and Calcium Acetate in Rats  

Microsoft Academic Search

The objective was to investigate the bioavailability and mech- anism of calcium absorption of calcium ascorbate (ASC) and calcium acetate (AC). A series of studies was performed in adult Sprague-Dawley male rats. In the first study, each group of rats (n = 10\\/group) was assigned to one of the five test meals labeled with 45Ca: (i) 25 mg calcium as

JIANWEI CAI; QINMIN ZHANG; MERYL E. WASTNEY; CONNIE M. WEAVER

345

Response of sugar maple to calcium addition to northern hardwood forest.  

PubMed

Watershed budget studies at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, have demonstrated high calcium depletion of soil during the 20th century due, in part, to acid deposition. Over the past 25 years, tree growth (especially for sugar maple) has declined on the experimental watersheds at the HBEF. In October 1999, 0.85 Mg Ca/ha was added to Watershed 1 (W1) at the HBEF in the form of wollastonite (CaSiO3), a treatment that, by summer 2002, had raised the pH in the Oie horizon from 3.8 to 5.0 and, in the Oa horizon, from 3.9 to 4.2. We measured the response of sugar maple to the calcium fertilization treatment on W1. Foliar calcium concentration of canopy sugar maples in W1 increased markedly beginning the second year after treatment, and foliar manganese declined in years four and five. By 2005, the crown condition of sugar maple was much healthier in the treated watershed as compared with the untreated reference watershed (W6). Following high seed production in 2000 and 2002, the density of sugar maple seedlings increased significantly on W1 in comparison with W6 in 2001 and 2003. Survivorship of the 2003 cohort through July 2005 was much higher on W1 (36.6%) than W6 (10.2%). In 2003, sugar maple germinants on W1 were approximately 50% larger than those in reference plots, and foliar chlorophyll concentrations were significantly greater (0.27 g/m2 vs. 0.23 g/m2 leaf area). Foliage and fine-root calcium concentrations were roughly twice as high, and manganese concentrations twice as low in the treated than the reference seedlings in 2003 and 2004. Mycorrhizal colonization of seedlings was also much greater in the treated (22.4% of root length) than the reference sites (4.4%). A similar, though less dramatic, difference was observed for mycorrhizal colonization of mature sugar maples (56% vs. 35%). These results reinforce and extend other regional observations that sugar maple decline in the northeastern United States and southern Canada is caused in part by anthropogenic effects on soil calcium status, but the causal interactions among inorganic nutrition, physiological stress, mycorrhizal colonization, and seedling growth and health remain to be established. PMID:16761605

Juice, Stephanie M; Fahey, Timothy J; Siccama, Thomas G; Driscoll, Charles T; Denny, Ellen G; Eagar, Christopher; Cleavitt, Natalie L; Minocha, Rakesh; Richardson, Andrew D

2006-05-01

346

Portable fluorescence photometer for monitoring free calcium  

NASA Astrophysics Data System (ADS)

We introduce a compact and portable photometric system for measurements of the calcium dynamics in cells. The photometer is designed for applications in centrifuges or in zero gravity environment and thus extremely compact and reliable. It operates with the calcium-sensitive dye Indo-1. The excitation wavelength of 345 nm is generated by frequency doubling of a laser diode. Two compact photomultiplier tubes detect the fluorescent emission. The electronics provide the sensitivity of photon counting combined with simultaneous measurement of the temperature, of air pressure, and of gravitational force. Internal data storage during the experiment is possible. A newly developed cell chamber stabilizes the cell temperature to 37.0+/-0.1 °C and includes a perfusion system to supply the cells with medium. The system has a modular setup providing the possibility of changing the light source and detectors for investigation of ions other than calcium. Measurements of the intracellular calcium concentration are based on a comprehensive calibration of our system. First experiments show that the calcium dynamics of osteosarcoma cells stimulated by parathyroid hormone is observable.

Struckmeier, Jens; Klopp, Erk; Born, Matthias; Hofmann, Martin; Tenbosch, Jochen; Jones, David B.

2000-12-01

347

Sintering of calcium phosphate bioceramics.  

PubMed

Calcium phosphate ceramics have become of prime importance for biological applications in the field of bone tissue engineering. This paper reviews the sintering behaviour of these bioceramics. Conventional pressureless sintering of hydroxyapatite, Ca10(PO4)6(OH)2, a reference compound, has been extensively studied. Its physico-chemistry is detailed. It can be seen as a competition between two thermally activated phenomena that proceed by solid-state diffusion of matter: densification and grain growth. Usually, the objective is to promote the first and prevent the second. Literature data are analysed from sintering maps (i.e. grain growth vs. densification). Sintering trajectories of hydroxyapatite produced by conventional pressureless sintering and non-conventional techniques, including two-step sintering, liquid phase sintering, hot pressing, hot isostatic pressing, ultrahigh pressure, microwave and spark plasma sintering, are presented. Whatever the sintering technique may be, grain growth occurs mainly during the last step of sintering, when the relative bulk density reaches 95% of the maximum value. Though often considered very advantageous, most assisted sintering techniques do not appear very superior to conventional pressureless sintering. Sintering of tricalcium phosphate or biphasic calcium phosphates is also discussed. The chemical composition of calcium phosphate influences the behaviour. Similarly, ionic substitutions in hydroxyapatite or in tricalcium phosphate create lattice defects that modify the sintering rate. Depending on their nature, they can either accelerate or slow down the sintering rate. The thermal stability of compounds at the sintering temperature must also be taken into account. Controlled atmospheres may be required to prevent thermal decomposition, and flash sintering techniques, which allow consolidation at low temperature, can be helpful. PMID:23212081

Champion, E

2012-12-02

348

Assessment of calcium balance in patients on hemodialysis, based on ionized calcium and parathyroid hormone responses.  

PubMed

Background: Identification of the underlying causes of secondary hyperparathyroidism (SHPT) in individual patients on hemodialysis (HD) is hampered by the lack of clinically reliable information on calcium balance. The aim of this study was to assess calcium balance during HD sessions with a method that is applicable in day-to-day practice.?Methods: Plasma ionized calcium (pCa2+) and ?parathyroid hormone (PTH) were measured at the beginning and end of HD to evaluate calcium fluxes in 23 patients on a dialysate calcium (DCa) concentration of 1.25 mmol/L.?Results: HD with a DCa of 1.25 mmol/L caused a ?decrease in pCa2+ from 1.15 ± 0.01 mmol/L to 1.09 ± 0.01 mmol/L (p<0.0001) and increased plasma PTH from 26.7 ± 1.8 pmol/L to 37.0 ± 2.9 pmol/L (p<0.0001). The changes in pCa2+ were inversely related to the predialysis pCa2+ levels (R2 = 0.86, p<0.001). Patients with a predialysis pCa2+ >1.06 mmol/L had a calcium efflux, whereas those with a predialysis pCa2+ <1.06 mmol/L had a calcium influx during HD. ?Conclusion: The results suggest that measurement of pCa2+ and PTH at the beginning and the end of HD provides useful information about calcium fluxes in individual patients. Further validation of this approach ?is warranted. PMID:23475464

Bech, Anneke; Reichert, Louis; Telting, Darryl; de Boer, Hans

2013-03-04

349

The reaction mechanism of calcium-activated photoprotein bioluminescence.  

PubMed

Calcium-activated photoproteins are important and useful bioluminescent reagents for detecting the calcium ion (Ca2+) in biological systems. In conjunction with photon imaging technology, they can be used to observe Ca2+-related life processes in a living cell. To develop useful applications of calcium-activated photoproteins, we need to understand the molecular basis of the bioluminescence reaction. For this purpose, this review describes the oxygenation, chemiexcitation, and light emission processes of calcium-activated photoproteins in the bioluminescence reaction together with the fundamental chemistry of the luminous substrate, coelenterazine, based on recent results from mechanistic chemical studies of these primary processes. Finally, the whole reaction mechanism, including the active site structures of apoproteins, along with available information about the molecular mechanism and the crystallographic structures of calcium-activated photoproteins are summarized. PMID:22039804

Hirano, Takashi

2012-11-01

350

Inositol trisphosphate and calcium signalling  

NASA Astrophysics Data System (ADS)

Inositol trisphosphate is a second messenger that controls many cellular processes by generating internal calcium signals. It operates through receptors whose molecular and physiological properties closely resemble the calcium-mobilizing ryanodine receptors of muscle. This family of intracellular calcium channels displays the regenerative process of calcium-induced calcium release responsible for the complex spatiotemporal patterns of calcium waves and oscillations. Such a dynamic signalling pathway controls many cellular processes, including fertilization, cell growth, transformation, secretion, smooth muscle contraction, sensory perception and neuronal signalling.

Berridge, Michael J.

1993-01-01

351

Genetic gain and cost efficiency of marker-assisted selection of maize for improved resistance to multiple foliar pathogens  

Microsoft Academic Search

Northern corn leaf blight (NCLB) caused by Exserohilum turcicum, gray leaf spot (GLS) caused by Cercospora zeae-maydis and maize streak caused by maize streak Mastrevirus (MSV) are the most destructive foliar diseases limiting maize production in sub-Saharan Africa. Most foliar diseases of maize\\u000a are managed using quantitative (partial) resistance, and previous studies have reported quantitative trait loci associated\\u000a with host

Godfrey AseaBindiganavile; Bindiganavile S. Vivek; Patrick E. Lipps; Richard C. Pratt

352

Identification of quantitative trait loci associated with resistance to foliar diseases in sorghum [ Sorghum bicolor (L.) Moench  

Microsoft Academic Search

Forage sorghum cultivars grown in India are susceptible to various foliar diseases, of which anthracnose, rust, zonate leaf\\u000a spot, drechslera leaf blight and target leaf spot cause severe damage. We report here the quantitative trait loci (QTLs) conferring\\u000a resistance to these foliar diseases. QTL analysis was undertaken using 168 F7 recombinant inbred lines (RILs) of a cross between a female

S. Murali Mohan; R. Madhusudhana; K. Mathur; D. V. N. Chakravarthi; Sanjay Rathore; R. Nagaraja Reddy; K. Satish; G. Srinivas; N. Sarada Mani; N. Seetharama

2010-01-01

353

Ozone sensitivity of Fagus sylvatica and Fraxinus excelsior young trees in relation to leaf structure and foliar ozone uptake  

Microsoft Academic Search

During the summer of 2001, 2-year-old Fraxinus excelsior and Fagus sylvatica plants were subjected to ozone-rich environmental conditions at the Regional Forest Nursery at Curno (Northern Italy). Atmospheric ozone concentrations and stomatal conductance were measured, in order to calculate the foliar fluxes by means of a one-dimensional model. The foliar structure of both species was examined (thickness of the lamina

Giacomo Gerosa; Riccardo Marzuoli; Filippo Bussotti; Marica Pancrazi; Antonio Ballarin-Denti

2003-01-01

354

Spatial patterns of foliar stable carbon isotope compositions of C 3 plant species in the Loess Plateau of China  

Microsoft Academic Search

The spatial pattern of foliar stable carbon isotope compositions (?13C) of dominant species and their relationships with environmental factors in seven sites, Yangling, Yongshou, Tongchuan, Fuxian,\\u000a Ansai, Mizhi and Shenmu, standing from south to north in the Loess Plateau of China, was studied. The results showed that\\u000a in the 121 C3 plant samples collected from the Loess Plateau, the foliar

Shuxia Zheng; Zhouping Shangguan

2007-01-01

355

Phytotoxic activity of foliar volatiles and essential oils of Calamintha nepeta (L.) Savi.  

PubMed

Foliar volatiles and essential oils of Calamintha nepeta (L.) Savi, a Mediterranean plant species belonging to the Labiatae family, were investigated for their phytotoxic activities on seed germination and root growth of crops (Lactuca sativa L. and Raphanus sativus L.) and weed species (Lolium perenne L. and Amaranthus retroflexus L.). Foliar volatiles of C. nepeta (L.) Savi strongly inhibited both germination and root growth of lettuce, and its essential oils, especially at 125, 250 and 500 ?L/L, inhibited both processes in lettuce, radish and A. retroflexus L. species, while displaying a little effect on L. perenne L. By GC-MS, 28 chemicals were identified: 17 monoterpenes, 8 sesquiterpenes, 1 diterpene and 2 miscellaneous. Pulegone was the main constituent of the C. nepeta (L.) Savi essential oils. The terpenic components of essentials oils were probably responsible for the phytotoxic activities. PMID:23216166

Araniti, Fabrizio; Lupini, Antonio; Sorgonà, Agostino; Statti, Giancarlo Antonio; Abenavoli, Maria Rosa

2012-12-06

356

Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.  

ERIC Educational Resources Information Center

The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)

Henrickson, Charles H.; Robinson, Paul R.

1979-01-01

357

Gravimetric Determination of Calcium as Calcium Carbonate Hydrate.  

ERIC Educational Resources Information Center

|The gravimetric determination of calcium as calcium carbonate is described. This experiment is suitable for undergraduate quantitative analysis laboratories. It is less expensive than determination of chloride as silver chloride. (BB)|

Henrickson, Charles H.; Robinson, Paul R.

1979-01-01

358

Draft Guidance on Calcium Acetate Active ingredient: Calcium ...  

Center for Drug Evaluation (CDER)

Text VersionPage 1. Contains Nonbinding Recommendations Draft Guidance on Calcium Acetate ... Active ingredient: Calcium Acetate Form/Route: Tablets/Oral ... More results from www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation

359

Calcium Signalling: Fishing Out Molecules of Mitochondrial Calcium Transport  

PubMed Central

Cellular energy metabolism, survival and death are controlled by mitochondrial calcium signals originating in the cytoplasm. Now, RNAi studies link three proteins — MICU1, NCLX and LETM1 — to the previously unknown molecular mechanism of mitochondrial calcium transport.

Hajnoczky, Gyorgy; Csordas, Gyorgy

2011-01-01

360

Regional patterns in foliar 15N across a gradient of nitrogen deposition in the northeastern US  

Microsoft Academic Search

Recent studies have demonstrated that natural abundance 15N can be a useful tool for assessing nitrogen saturation, because as nitrification and nitrate loss increase, ?15N of foliage and soil also increases. We measured foliar ?15N at 11 high-elevation spruce-fir stands along an N deposition gradient in 1987–1988 and at seven paired northern hardwood and spruce-fir stands in 1999. In 1999,

Linda H. Pardo; Steven G. McNulty; Johnny L. Boggs; Sara Duke

2007-01-01

361

FOLIAR BORON ENHANCES LEAF CHLOROSIS AND DOES NOT AFFECT PECAN PRODUCTION AND NUT QUALITY  

Microsoft Academic Search

The narrow range between boron (B) deficiency and toxicity compared with other micronutrients is a serious problem for sustainable production of pecan throughout the southwest United States of America. However, performance of pecan under foliar B is lacking. Five B treatments (0, 0.5, 1.0, 1.5 kg B ha, water spray) were applied to 27 years old trees of pecan variety

Shad Khan Khalil; John Mexal; Abdur Rehman; Amanullah; Fida Muhammad; Amir Zaman Khan

2011-01-01

362

Effects of ozone on morphogenesis of the foliar embryos of bryophyllum calycinum Salisb  

SciTech Connect

Explants from three different ages, including the foliar embryo of ozonated and non-ozonated marginal leaf tissue from Bryophyllum calycinum were cultured on modified formulations of Murashige and Skoog's medium. Kinetin 2,4-D and IAA were added to the media individually or in combination. The development of the embryos was affected by tissue age, media composition and prior exposure to ozone. The production of callus, shoots, roots and anthocyanin were all in response to different sets of culture conditions.

Rier, J.P.; Phillips, G. (Howard Univ., Washington, DC (USA))

1990-01-01

363

Patterns of Carbon, Nitrogen and Phosphorus Dynamics in Decomposing Foliar Litter in Canadian Forests  

Microsoft Academic Search

We examined the patterns of nitrogen (N) and phosphorus (P) gain, retention or loss in ten foliar tissues in a litterbag experiment\\u000a over 6 years at 18 upland forest sites in Canada, ranging from subarctic to cool temperate. N was usually retained in the\\u000a decomposing litter until about 50% of the original C remained. The peak N content in the

T. R. Moore; J. A. Trofymow; C. E. Prescott; J. Fyles; B. D. Titus

2006-01-01

364

Efeitos da radiação ultravioleta-B sobre a morfologia foliar de Arabidopsis thaliana (L.) Heynh. (Brassicaceae)  

Microsoft Academic Search

s -1 de radiação fotossinteticamente ativa (PAR) com ou sem 6 kJ m -2 s -1 de radiação UV-Bbe (UV-Bbe; UV-B biologicamente efetiva). Após 21 dias, 10 folhas de cada tratamento (com e sem radiação UV-B) foram coletadas para avaliar área foliar, massa fresca e seca, AEF, densidades estomáticas e de tricomas de ambas as faces da folha, espessura da

Maria Regina Torres Boeger; Mary E. Poulson

2006-01-01

365

Effect of Foliar Fertilizer as Seed Pretreatment on Yield Components in Common Wheat (Triticum aestivum L.)  

Microsoft Academic Search

Aim of this research is to evaluate the effect of foliar fertilizer as seed pre-treatment at different concentrations and times to the yield components in the ?kizce 96 common wheat (Triticum aestivum L) under field conditions of Central Anatolia in a split-split plot design with four replications during 1998-99 and 1999-2000 at the University of Ankara, Faculty of Agriculture, Haymana

Hakan ULUKAN

366

Costs of defense: correlated responses to divergent selection for foliar glucosinolate content in Brassica rapa  

Microsoft Academic Search

The evolutionary response of plant populations to herbivore imposed selection for defense may theoretically be constrained\\u000a by the costs of defense, yet few studies convincingly demonstrate such costs. We investigated possible constraints on the\\u000a evolution of defense in rapid cycling Brassica rapa by divergently selecting lines for investment in foliar glucosinolate content, a chemical defense in this species. Costs\\u000a would

Kirk A. StoweRobert; Robert J. Marquis

2011-01-01

367

Sucrose fatty acid esters enhance efficiency of foliar-applied urea-nitrogen to soybeans  

Microsoft Academic Search

A greenhouse study is described showing the effect of sucrose fatty acid esters (SFE) applied to soybeans (Glycine max (L.) Merrill cv Fukuyutaka) during the flowering and\\/or pod-filling periods on the efficiency of foliar-applied urea-nitrogen. SFE applied in combination with urea delayed senescence and when applied during both the flowering and pod-filling periods increased seed yields by 103% and nitrogen

M. Ikeda; W. K. Choi; Y. Yamada

1991-01-01

368

Measuring the relative particle foliar combustibility of WUI forest species located near athens  

Microsoft Academic Search

The relative particle foliar combustibility of seven dominant Mediterranean plant species from a wildland\\/urban interface\\u000a (WUI) area near Athens has been determined, using thermal analysis (TG, DTG and SDTA) under oxygen atmosphere, calorimetry\\u000a and a new lab-scale flame spread test. In addition, the moisture content, total ash content and elemental composition of forest\\u000a species were determined, in order to correlate

S. Liodakis; T. Kakardakis

2008-01-01

369

Tree resistance to Lymantria dispar caterpillars: importance and limitations of foliar tannin composition  

Microsoft Academic Search

The ability of foliar tannins to increase plant resistance to herbivores is potentially determined by the composition of the\\u000a tannins; hydrolyzable tannins are much more active as prooxidants in the guts of caterpillars than are condensed tannins.\\u000a By manipulating the tannin compositions of two contrasting tree species, this work examined: (1) whether increased levels\\u000a of hydrolyzable tannins increase the resistance

Raymond V. Barbehenn; Adam Jaros; Grace Lee; Cara Mozola; Quentin Weir; Juha-Pekka Salminen

2009-01-01

370

Foliar architecture and anatomy of Bernardia and other genera of Acalyphoideae (Euphorbiaceae)  

Microsoft Academic Search

A comparative study of leaf architecture and anatomy of 42 species of Bernardia and other genera related of Acalyphoideae was undertaken to identify characters that support infrageneric and specific delimitation.\\u000a Thirty variable foliar architectural and anatomical characters were studied. Some characters are consistent (e.g., venation\\u000a pattern, secondary and tertiary vein arrangement, presence or absence of agrophic veins, type of areoles,

Angélica Cervantes; Teresa Terrazas; Héctor M. Hernández

2009-01-01

371

Elevational and age gradients in hawaiian montane rainforest: foliar and soil nutrients  

Microsoft Academic Search

Soils and plants were sampled along an elevational gradient from 265–1675 m on a 133-and a 3100-year-old lava flow on Mauna Loa, Hawai'i. Soil organic matter and nutrients accumulated more rapidly at low elevation on the young flow, but reached higher levels at higher elevation on the old flow. Foliar nitrogen and phosphorus concentrations were less and specific leaf weight

Peter M. Vitousek; Pamela A. Matson; Douglas R. Turner

1988-01-01

372

pre-Pleistocene relicts? Evidence from foliar physiognomy, palaeoclimate, and phytogeography  

Microsoft Academic Search

Aim We ask whether contemporary forests of the Chilean Coastal Range can be considered to be direct and conservative descendants of pre-Pleistocene palaeofloras that occurred in southern South America from the Palaeogene to early Neogene periods (65-10 Ma), maintaining foliar physiognomies that do not match their present-day climate. We also identify the most likely ancestors of present-day coastal forests. Location

Luis Felipe Hinojosa; Juan J. Armesto; Carolina Villagran

373

Application of intact cell-based NFAT-?-lactamase reporter assay for Pasteurella multocida toxin-mediated activation of calcium signaling pathway  

PubMed Central

Pasteurella multocida toxin (PMT) stimulates and subsequently uncouples phospholipase C ?1 (PLC?1) signal transduction through its selective action on the alpha subunit of the Gq protein. Here, we describe the application of an NFAT-?-lactamase reporter assay as a functional readout for PMT-induced activation of the Gq-protein-coupled PLC?1-IP3-Ca2+ signaling pathway. Use of the NFAT-?-lactamase reporter assay with a cell-permeable fluorogenic substrate provides high sensitivity due to the absence of endogenous ?-lactamase activity in mammalian cells. This assay system was optimized for cell density, dose and time exposure of PMT stimulation. It is suited for quantitative characterization of PMT activity in mammalian cells and for use as a high-throughput screening method for PMT deletion and point mutants suitable for vaccine development. This method has application for diagnostic screening of clinical isolates of toxinogenic P. multocida.

Luo, Shuhong; Ho, Mengfei; Wilson, Brenda A.

2009-01-01

374

Calcium absorption from a new calcium delivery system (CCM)  

Microsoft Academic Search

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

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

1987-01-01

375

Foliar and soil deposition of pesticide sprays in peanuts and their washoff and runoff under simulated worst-case rainfall conditions.  

PubMed

There are few studies that relate the timing and amounts of pesticide washoff from plant foliage during rainfall to runoff losses at the edge of the field. We hypothesized that foliar deposits, if washed onto the soil slowly during rainfall, may then undergo less leaching during the period of infiltration that occurs prior to soil saturation and runoff, thus exhibiting larger runoff losses than pesticides on/in the soil at the beginning of rain. We measured the runoff of ethalfluralin, metolachlor, chlorothalonil, and rhodamine WT dye using simulated rainfall on 450 m2 mesoplots planted in peanut. Ethalfluralin was applied preplant incorporated, and metolachlor was applied preemergence on bare soil. Chlorothalonil and rhodamine WT were applied to the peanut canopy at maturity. Rainfall was simulated 24 h after each chemical application (in May and July, 1998, and May and August, 1999) using raindrop sprinklers, applying 5.5 +/- 0.5 cm over a 2 h period to create reasonable worst-case conditions; between 3 and 9 mm of runoff was generated. Volume-weighted average concentrations of chemicals in runoff were 7, 104, 163, and 179 ug L(-1) for ethalfluralin, metolachlor, chlorothalonil, and rhodamine WT, respectively. The total amounts of chemicals lost in the runoff events were 0.04 +/- 0.01, 0.2 +/- 0.1, 0.6 +/- 0.5, and 0.2 +/- 0.1, as percents of amounts applied, respectively. Rhodamine WT formed a vivid red solution on wetting and provided visual clues to the dynamics of chemical washoff/runoff. The washoff from rain-exposed peanut foliage appeared to be complete within a few minutes of the beginning of rainfall, and disappearance of dye from rain-exposed soil surface occurred within the first 10 min of rainfall. However, dye was present in runoff water at near-constant concentrations throughout the 2 h runoff event, indicating that near-constant amounts of chemical remained in the soil extraction zone. These results confirm earlier studies showing that soil incorporation at application significantly reduces runoff losses and that a majority of foliar residues can be washable if rainfall occurs within a few days after application. Runoff losses of foliar-applied pesticides were small relative to washoff amounts but were sensitive to runoff timing relative to washoff. PMID:15537318

Wauchope, R Don; Johnson, W Carroll; Sumner, Harold R

2004-11-17

376

Induced defensive response of myrtle oak to foliar insect herbivory in ambient and elevated CO2.  

PubMed

The rising level of atmospheric CO2 has stimulated several recent studies attempting to predict the effects of increased CO2 on ecological communities. However, most of these studies have been conducted in the benign conditions of the laboratory and in the absence of herbivores. In the current study, we utilized large octagonal chambers, which enclosed portions of an intact scrub-oak community to investigate the interactive effects of CO2 and insect herbivory on myrtle oak, Quercus myrtifolia. Specifically, we assessed the effects of ambient and elevated CO2 (2x current concentrations) on percent foliar nitrogen, C:N ratio, total relative foliar tannin content, and the presence of leaf damage caused by leaf mining and leaf chewing insects that feed on myrtle oak. Total foliar N declined and C:N ratios increased significantly in oaks in elevated CO2 chambers. The percentages of leaves damaged by either leafminers or leaf chewers tended to be lower in elevated compared to ambient chambers, but they co-occurred on leaves less than expected, regardless of CO2 treatment. Leaves that had been either mined or chewed exhibited a similar wounding or defensive response; they had an average of 25 and 21% higher protein binding ability, which is correlated with tannin concentration, compared to nondamaged control leaves, respectively. While the protein-binding ability (expressed as total percent tannin) of leaves from elevated CO2 was slightly higher than from leaves grown in ambient chambers, this difference was not significant. PMID:15303319

Rossi, Anthony M; Stiling, Peter; Moon, Daniel C; Cattell, Maria V; Drake, Bert G

2004-06-01

377

Differential effects of foliar endophytic fungi on insect herbivores attacking a herbaceous plant.  

PubMed

Foliar endophytic fungi appear to be ubiquitous in nature, occurring in a very wide range of herbaceous plants. However, their ecological role within forbs is very poorly known and interactions with foliar-feeding insects virtually unexplored. In this study, leaves of Cirsium arvense were infected with different combinations of endophyte fungi that had been previously isolated from this plant species. Two months later, leaf material was fed to larvae of a generalist insect, Mamestra brassicae, and adults of a specialist feeder, Cassida rubiginosa. Endophytes had different effects on the two insects; one species, Chaetomium cochliodes, reduced growth of M. brassicae but increased feeding by C. rubiginosa. Another species, Cladosporium cladosporioides, increased beetle feeding also, but had no effect on M. brassicae. Interactions were also seen between fungal species and dual infection with C. cladosporioides and Trichoderma viride greatly reduced beetle feeding. It is concluded that endophytes have significant effects on foliar feeding insects that differ with degree of specialism of the herbivore. We suggest that these effects are due to chemical changes in the host, brought about by fungal infection. These fungi have received remarkably little attention in the study of insect-plant interactions and yet could be important determinants of insect growth and even population dynamics. PMID:21989607

Gange, Alan C; Eschen, René; Wearn, James A; Thawer, Alim; Sutton, Brian C

2011-10-12

378

The contribution of foliar endophytes to quantitative resistance to Melampsora rust.  

PubMed

Foliar endophytes of Populus do not induce the hypersensitive response associated with major genes for resistance to Melampsora leaf rust. But they could contribute to the quantitative resistance that represents a second line of defense. Quantitative resistance is thought to be determined by suites of minor genes in both host and pathogen that are influenced by the abiotic environment. Here, we determined the relative importance to quantitative resistance of foliar endophytes, one element of the biotic environment. Leaves of six host genotypes differing in genetic resistance to Melampsora × columbiana were inoculated first with one of four foliar endophytes (Stachybotrys sp., Trichoderma atroviride, Ulocladium atrum or Truncatella angustata), and then with Melampsora. These endophytes greatly reduced rust severity within inoculated leaves (i.e. local effects), but they had no systemic effect on rust of leaves not inoculated with endophytes. Differences among endophytes and their controls explained 54% of the total variation in quantitative resistance (i.e. rust severity); the six host/pathogen genotypes explained just 5%. In terms of magnitude of effect on rust severity, Stachybotrys, Trichoderma, Ulocladium and Truncatella were ranked in this order on all host/pathogen genotypes. Endophytes may contribute significantly to quantitative resistance to Melampsora in leaves of Populus. PMID:23228058

Raghavendra, Anil K H; Newcombe, George

2012-12-10

379

Rates of foliar penetration of chelated Fe(III): role of light, stomata, species, and leaf age.  

PubMed

Rates of foliar penetration of Fe(III) chelates of imidodisuccinic acid (IDHA), ligninsulfonic acid (Natrel), and citric acid (ammonium ferric citrate) were studied at 20 degrees C using a leaf disk method. After drying of the donor droplets, the humidity over the donor residues was maintained at 100% because Fe(III) chelates deliquesce only when humidity is higher than 90%. The wetting agent Glucopon 215 CSUP was added at a concentration of 0.2 g L(-1) to all donor solutions. With fully expanded stomatous broad bean leaves, penetration of Fe-IDHA followed first-order kinetics and rate constants of penetration were higher in light (0.073 h(-1)) than in the dark (0.042 h(-1)). Permeability of broad been leaves to CaCl2 was about 8 times higher than to Fe-IDHA. Doubling the Fe-IDHA concentration in the donor from 2.5 to 5 mmol L(-1) decreased rate constants of Fe-IDHA penetration by a factor of 2.2. Adding the silicon surfactant Break Thru S240 at 10 g L(-1) to the donor induced infiltration of open stomata and about 80% of the applied Fe-IDHA penetrated during droplet drying, while with Glucopon 215 CSUP stomatal infiltration was not observed. With broad bean leaves, penetration of Natrel and ammonium ferric citrate also followed first-order kinetics and rate constants were also higher in light than in the dark. Adaxial astomatous surfaces of fully expanded pear, apple, and grapevine leaves were practically impermeable to Fe-IDHA while stomatous abaxial leaf surfaces were permeable, but rate constants of penetration decreased with time and differed greatly among species. Astomatous surfaces of young unfurling grapevine and peach leaves were permeable to Fe-IDHA, but permeability of stomatous surfaces was much higher. The effect of light on permeability of stomatous leaf surfaces is attributed to the presence of aqueous pores in cuticles over guard cells, and it is suggested that permeability of these pores increases as stomata open. Consequences of these results for foliar applications of Fe chelates are discussed. PMID:16939343

Schlegel, Thomas K; Schönherr, Jörg; Schreiber, Lukas

2006-09-01

380

21 CFR 172.410 - Calcium silicate.  

Code of Federal Regulations, 2013 CFR

...Drugs 3 2013-04-01 2013-04-01 false Calcium silicate. 172.410 Section 172.410 Food...HUMAN CONSUMPTION Anticaking Agents § 172.410 Calcium silicate. Calcium silicate, including synthetic calcium...

2013-04-01

381

76 FR 71459 - Prohexadione Calcium; Pesticide Tolerances  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2010-0780; FRL-9326-4] Prohexadione Calcium; Pesticide Tolerances AGENCY: Environmental...tolerance for residues of prohexadione calcium in or on sweet cherry. BASF Corporation...the plant growth regulator prohexadione calcium, calcium,...

2011-11-18

382

21 CFR 573.240 - Calcium periodate.  

Code of Federal Regulations, 2013 CFR

...accordance with the following prescribed conditions: (a) The additive is produced by reacting calcium iodate with calcium hydroxide or calcium oxide to form a substance consisting of not less than 60 percent by weight of penta calcium...

2013-04-01

383

Sensitivity to Calcium Intake in Calcium Stone Forming Patients  

Microsoft Academic Search

The absorptive or renal origin of hypercalciuria can be discriminated using an acute oral calcium load test (ACLT). Of 86 patients with calcium oxalate kidney stones, 28 (23%) were found to be hypercalciuric (HCa) and 58 (67%) normocalciuric (NCa) on their customary free diet, containing 542 ± 29 mg\\/ day (mean ± SE) of calcium. Since the apparently normal 24-hour

Ita Pfeferman Heilberg; Ligia Araujo Martini; Sergio Antonio Draibe; Horacio Ajzen; Oswaldo Luiz Ramos; Nestor Schor

1996-01-01

384

Calcium Entry Leads to Inactivation of Calcium Channel in Paramecium  

Microsoft Academic Search

Under depolarizing voltage clamp of Paramecium an inward calcium current developed and subsequently relaxed within 10 milliseconds. The relaxation was substantially slowed when most of the extracellular calcium was replaced by either strontium or barium. Evidence is presented that the relaxation is not accounted for by a drop in electromotive force acting on calcium, or by activation of a delayed

Paul Brehm; Roger Eckert

1978-01-01

385

[Calcium and vitamins].  

PubMed

Sufficient calcium intake and vitamin D adequacy are prerequisite for any pharmacological treatment for osteoporosis. The latter has been often ignored in Japan, partly because serum 25(OH)D measurement is not reimbursed by health insurance policy and perhaps because natural vitamin D cannot be prescribed by phySicians in this country. Here, some of the recent metaanalyses of calcium, vitamin D metabolites, and vitamin K on osteoporosis are reviewed. A new vitamin D metabolite, eldecalcitol, will also be discussed. PMID:21774368

Okazaki, Ryo

2011-07-01

386

Calcium Transport in the Intestine.  

National Technical Information Service (NTIS)

The effects of colchicine and cytochalasin B (CB) on the ultrastructure, calcium distribution and transport characteristics of the intestine were investigated. Colchicine at low doses inhibited both cellular uptake and transepithelial transport of calcium...

B. P. Halloran

1976-01-01

387

A sensor for calcium uptake  

PubMed Central

Mitochondria — the cell’s power plants — increase their energy production in response to calcium signals in the cytoplasm. A regulator of the elusive mitochondrial calcium channel has now been identified.

Collins, Sean; Meyer, Tobias

2011-01-01

388

Electrolytic Production of Calcium Metal.  

National Technical Information Service (NTIS)

The Bureau of Mines developed an alternative electrochemical process for the production of calcium metal. The current industrial practice is costly, complex, and inefficient. The Bureau method involves electrowinning of a calcium-tin alloy followed by ele...

J. J. Lukasko J. E. Murphy

1990-01-01

389

Antagonist effects of calcium on borosilicate glass alteration  

NASA Astrophysics Data System (ADS)

Numerous studies have been conducted on glass and cement durability in contact with water, but very little work to date has focused directly on interactions between the two materials. These interactions are mostly controlled by silicon-calcium reactivity. However, the physical and chemical processes involved remain insufficiently understood to predict the evolution of coupled glass-cement systems used in several industrial applications. Results are reported from borosilicate glass alteration in calcium-rich solutions. Our data show that four distinct behaviors can be expected according to the relative importance of three key parameters: the pH, the reaction progress (short- or long-term alteration) and the calcium concentration. Glass alteration is thus controlled by specific mechanisms depending on the solution chemistry: calcium complexation at the glass surface, precipitation of calcium silicate hydrates (C-S-H) or calcium incorporation in the altered layer. These findings highlight the impact of silicon-calcium interactions on glass durability and open the way for a better understanding of glass-cement mixing in civil engineering applications as well as in nuclear waste storage.

Mercado-Depierre, S.; Angeli, F.; Frizon, F.; Gin, S.

2013-10-01

390

Molten salt applications in materials processing  

Microsoft Academic Search

The science of molten salt electrochemistry for electrowinning of reactive metals, such as calcium, and its in situ application in pyro-reduction has been described. Calcium electrowinning has been performed in a 5–10wt% calcium oxide–calcium chloride molten salt by the electrolytic dissociation of calcium oxide. This electrolysis requires the use of a porous ceramic sheath around the anode to keep the

Brajendra Mishra; David L. Olson

2005-01-01

391

Calcium in Pregnancy and Lactation  

Microsoft Academic Search

Pregnancy and lactation are times of high calcium demand. Approximately 25 to 30 g of calcium are transferred to the fetal\\u000a skeleton by the end of pregnancy. The fetus accumulates 2–3 mg\\/d of calcium during the first trimester, increasing to 250\\u000a mg\\/d during the third trimester (1). Maternal calcium losses to breast milk are approx 200–240 mg\\/d (2). Considering that

Heidi J. Kalkwarf

392

Quantifying Foliar Pigment Concentrations of Temperate Forest Species Using Digital Photography and Hyperspectral Reflectance Indices  

NASA Astrophysics Data System (ADS)

Determination of leaf chlorophyll content is a common and important procedure for plant scientists. There are many multispectral techniques for non destructive in-vivo, estimation of chlorophyll in foliage. Although much has been done to explore the estimation of foliar pigments using remote sensing, very little work has been done exploring the potential that basic, affordable, digital cameras may have for such analysis. This study utilizes a combination of digital photography, hyperspectral laboratory remote sensing, and chlorophyll extractions to determine if digital photographs can be used to accurately predict foliar chlorophyll concentrations as well to compare this digital approach with several common spectral indices used for estimating foliar chlorophyll content. Foliar materials for this study come from three sources. A large collection of samples were collected (60) from 9 common temperate forest species in July and late September over a 1 kilometer area at the Bartlett Experimental Forest in northern New Hampshire. Secondly, 15 trees were selected in a forested setting near the University of New Hampshire for more intensive phenological analysis. These samples consist of 5 white pine (Pinus strobus), 5 black oak (Quercus velutina) and 5 sugar maple (Acer saccharum). Finally, dozens of samples of white pine utilized in Forest Watch, a successful K-12 science outreach which assesses the impact of tropospheric ozone on forest health in New England, were also analyzed for this study. For all samples in this study, chlorophyll extractions were conducted to determine chlorophyll a, chlorophyll b, and total chlorophyll concentrations. Laboratory spectral analysis was performed using a GER 2600 Spectroradiometer to determine hyperspectral estimates of chlorophyll content using a Red Edge Inflection Point (REIP) approach, as well as a Transformed Chlorophyll Absorption Reflectance Index/Optimized Soil Adjusted Vegetation Index (TCARI/OSAVI) approach. These measures of chlorophyll estimation were utilized to determine whether red, green and blue spectral data from digital images taken with a Kodak C713 model camera could be used to estimate foliar chlorophyll concentrations in forest foliage. Preliminary results of this study will be presented.

Gagnon, M. T.; Rock, B. N.; Jahnke, L. S.; Lee, T. D.

2008-12-01

393

Role of Calcium in Osteoporosis.  

National Technical Information Service (NTIS)

Calcium requirements may vary throughout the lifespan. During the growth years and up to age 25 to 30, it is important to maximize dietary intake of calcium to maintain positive calcium balance and achieve peak bone mass, thereby possibly decreasing the r...

C. D. Arnaud S. D. Sanchez

1991-01-01

394

Osteoinduction by calcium phosphate biomaterials  

Microsoft Academic Search

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

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

1998-01-01

395

Stable Prenucleation Calcium Carbonate Clusters  

Microsoft Academic Search

Calcium carbonate forms scales, geological deposits, biominerals, and ocean sediments. Huge amounts of carbon dioxide are retained as carbonate ions, and calcium ions represent a major contribution to water hardness. Despite its relevance, little is known about the precipitation mechanism of calcium carbonate, and specified complex crystal structures challenge the classical view on nucleation considering the formation of metastable ion

Denis Gebauer; Antje Völkel; Helmut Cölfen

2008-01-01

396

Plant protein and calcium balance  

Microsoft Academic Search

The effect of low protein intake from plant sources on calcium excretions and calcium balance of seven young adults was investigated. The diets (four combinations of egg, groundnut and soyabean nitrogen) furnished 43 g protein (0.58 g protein\\/kg) and 550 mg calcium daily.

Olufunmike A. Ajayi

1977-01-01

397

Revisiting intracellular calcium signaling semantics  

Microsoft Academic Search

Cells use intracellular free calcium concentration changes for signaling. Signal encoding occurs through both spatial and temporal modulation of the free calcium concentration. The encoded message is detected by an ensemble of intracellular sensors forming the family of calcium-binding proteins (CaBPs) which must faithfully translate the message using a new syntax that is recognized by the cell. The cell is

Jacques Haiech; Emilie Audran; Marie Fève; Raoul Ranjeva; Marie-Claude Kilhoffer

2011-01-01

398

Letter: Calcium and blood pressure  

Microsoft Academic Search

While I greatly enjoyed the editorial by Prof. Kaplan (1988;2:269-274) on calcium and blood pressure, I do not agree with his conclusion that until the biochemical markers for responsiveness to calcium supplements are better defined (p. 273, last para.), calcium should not be used in the treatment of hypertension. One of the striking problems is that most of us are

R. B. Singh

1990-01-01

399

Calcium and Vitamin D  

Technology Transfer Automated Retrieval System (TEKTRAN)

Adequate intakes of vitamin D and calcium are essential preventative measures and essential components of any therapeutic regimen for osteoporosis. Vitamin D is also important for the prevention of falls. Current evidence suggests that a 25-hydroxyvitamin D level of 75 nmol/L (30 ng/ml) or higher ...

400

Calcium signaling in osteoclasts  

Microsoft Academic Search

It has long been known that many bone diseases, including osteoporosis, involve abnormalities in osteoclastic bone resorption. As a result, there has been intense study of the mechanisms that regulate both the differentiation and bone resorbing function of osteoclast cells. Calcium (Ca2+) signaling appears to play a critical role in the differentiation and functions of osteoclasts. Cytoplasmic Ca2+ oscillations occur

Sung-Yong Hwang; James W. Putney

2011-01-01

401

Variability of calcium absorption  

Microsoft Academic Search

Variability in calcium absorption was estimated in three groups of normal subjects in whom Ca absorption was measured by standard isotopic-tracer methods at interstudy intervals ranging from 1 to 4 mo. Fifty absorption tests were performed in 22 subjects. Each was done in the morning after an overnight fast with an identical standard breakfast containing a Ca load of approximately

R. P. Heaney; R. R. Recker; S. M. Hinders

1988-01-01

402

Calcium silicate insulation structure  

DOEpatents

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

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

1995-01-01

403

CALCIUM AND PHOSPHORUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

This chapter provides a comprehensive overview of the biochemical, physiological and molecular aspects of calcium (Ca) and phosphorus (P) in human nutrition. Specific topics include: the chemical properties of Ca and P; physiological and metabolic functions of Ca and P; hormonal regulation, homeosta...

404

Modeling Mercury's Calcium Exosphere  

Microsoft Academic Search

Three elements (H, He, O) were seen in emission in Mercury's atmosphere by the UV spectrometer onboard the Mariner 10 spacecraft (Broadfoot et al., Science 185, 1974). Two additional species (Na and K) were discovered by Potter and Morgan two decades later using ground-based telescopes (Potter and Morgan, Science 229, 1985; Icarus 67, 1986). Calcium was discovered in Mercury's exosphere

R. Killen; T. Bida; M. Sarantos; D. Boice

2002-01-01

405

Calcium Chromate Drying Studies.  

National Technical Information Service (NTIS)

Samples of calcium chromate were heated at 110 and 400 exp 0 C for specified periods of time to determine the percent weight loss under these conditions. Data indicate that a drying time of 8 hours at 110 exp 0 C plus 4 hours at 400 exp 0 C for milled sam...

B. M. Dillard C. P. Lofton E. N. Kling

1977-01-01

406

Setting Reaction and Hardening of an Apatitic Calcium Phosphate Cement  

Microsoft Academic Search

The combination of self-setting and biocompatibility makes calcium phosphate cements potentially useful materials for a variety of dental applications. The objective of this study was to investigate the setting and hardening mechanisms of a cement-type reaction leading to the formation of calcium-deficient hydroxyapatite at low temperature. Reactants used were a-tricalcium phosphate containing 17 wt% ?-tricalcium phosphate, and 2 wt% of

M. P. Ginebra; E. Fernández; E. A. P. De Maeyer; R. M. H. Verbeeck; M. G. Boltong; J. Ginebra; F. C. M. Driessens; J. A. Planell

1997-01-01

407

Calcium aluminate in alumina  

NASA Astrophysics Data System (ADS)

The properties of ceramic materials are determined not only by the composition and structure of the phases present, but also by the distribution of impurities, intergranular films and second phases. The phase distribution and microstructure both depend on the fabrication techniques, the raw materials used, the phase-equilibrium relations, grain growth and sintering processes. In this dissertation research, various approaches have been employed to understand fundamental phenomena such as grain growth, impurity segregation, second-phase formation and crystallization. The materials system chosen was alumina intentionally doped with calcium. Atomic-scale structural analyses of grain boundaries in alumina were carried on the processed samples. It was found that above certain calcium concentrations, CA6 precipitated as a second phase at all sintering temperatures. The results also showed that abnormal grain growth can occur after precipitation and it is not only related to the calcium level, but it is also temperature dependent. In order to understand the formation mechanism of CA6 precipitates in calcium doped alumina samples, several studies have been carried out using either bulk materials or thin films The crystallization of CA2 and CA6 powders has been studied. Chemical processing techniques were used to synthesize the powders. It was observed that CA2 powders crystallized directly, however CA6 powders crystallized through gamma-Al 2O3 solid solution. The results of energy-loss near-edge spectrometry confirmed that gamma-Al2O3 can dissolve calcium. Calcium aluminate/alumina reaction couples have also been investigated. All reaction couples were heat treated following deposition. It was found that gamma-Al2O3 was formed at the interface as a result of the interfacial reaction between the film and the substrate. gamma-Al 2O3 at the interface was stable at much higher temperatures compared to the bulk gamma-Al2O3 formed prior to the CA6 crystallization. In order to complement the studies carried out on the calcium aluminate phases, energy-loss near-edge structure (ELNES) fingerprints of CA2 and CA6 were obtained. It was shown that it is possible to distinguish these phases from each other by comparing the ELNES fingerprints. Theoretical calculations of ELNES were used to assign spectral features to certain symmetry environments that can later be used to understand the structures of unknown materials.

Altay, Arzu

408

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

Microsoft Academic Search

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

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

1989-01-01

409

Coupled nitrogen and calcium cycles in forests of the Oregon Coast Range  

USGS Publications Warehouse

Nitrogen (N) is a critical limiting nutrient that regulates plant productivity and the cycling of other essential elements in forests. We measured foliar and soil nutrients in 22 young Douglas-fir stands in the Oregon Coast Range to examine patterns of nutrient availability across a gradient of N-poor to N-rich soils. N in surface mineral soil ranged from 0.15 to 1.05% N, and was positively related to a doubling of foliar N across sites. Foliar N in half of the sites exceeded 1.4% N, which is considered above the threshold of N-limitation in coastal Oregon Douglas-fir. Available nitrate increased five-fold across this gradient, whereas exchangeable magnesium (Mg) and calcium (Ca) in soils declined, suggesting that nitrate leaching influences base cation availability more than soil parent material across our sites. Natural abundance strontium isotopes (87Sr/86Sr) of a single site indicated that 97% of available base cations can originate from atmospheric inputs of marine aerosols, with negligible contributions from weathering. Low annual inputs of Ca relative to Douglas-fir growth requirements may explain why foliar Ca concentrations are highly sensitive to variations in soil Ca across our sites. Natural abundance calcium isotopes (??44Ca) in exchangeable and acid leachable pools of surface soil measured at a single site showed 1 per mil depletion relative to deep soil, suggesting strong Ca recycling to meet tree demands. Overall, the biogeochemical response of these Douglas-fir forests to gradients in soil N is similar to changes associated with chronic N deposition in more polluted temperate regions, and raises the possibility that Ca may be deficient on excessively N-rich sites. We conclude that wide gradients in soil N can drive non-linear changes in base-cation biogeochemistry, particularly as forests cross a threshold from N-limitation to N-saturation. The most acute changes may occur in forests where base cations are derived principally from atmospheric inputs. ?? 2006 Springer Science+Business Media, Inc.

Perakis, S. S.; Maguire, D. A.; Bullen, T. D.; Cromack, K.; Waring, R. H.; Boyle, J. R.

2006-01-01

410

Coupled nitrogen and calcium cycling in forests of the Oregon Coast Range  

USGS Publications Warehouse

Nitrogen (N) is a critical limiting nutrient that regulates plant productivity and the cycling of other essential elements in forests. We measured foliar and soil nutrients in 22 young Douglas-fir stands in the Oregon Coast Range to examine patterns of nutrient availability across a gradient of N-poor to N-rich soils. N in surface mineral soil ranged from 0.15 to 1.05% N, and was positively related to a doubling of foliar N across sites. Foliar N in half of the sites exceeded 1.4% N, which is considered above the threshold of N-limitation in coastal Oregon Douglas-fir. Available nitrate increased five-fold across this gradient, whereas exchangeable magnesium (Mg) and calcium (Ca) in soils declined, suggesting that nitrate leaching influences base cation availability more than soil parent material across our sites. Natural abundance strontium isotopes (87Sr/86Sr) of a single site indicated that 97% of available base cations can originate from atmospheric inputs of marine aerosols, with negligible contributions from weathering. Low annual inputs of Ca relative to Douglas-fir growth requirements may explain why foliar Ca concentrations are highly sensitive to variations in soil Ca across our sites. Natural abundance calcium isotopes (I'44Ca) in exchangeable and acid leachable pools of surface soil measured at a single site showed 1 per mil depletion relative to deep soil, suggesting strong Ca recycling to meet tree demands. Overall, the biogeochemical response of these Douglas-fir forests to gradients in soil N is similar to changes associated with chronic N deposition in more polluted temperate regions, and raises the possibility that Ca may be deficient on excessively N-rich sites. We conclude that wide gradients in soil N can drive non-linear changes in base-cation biogeochemistry, particularly as forests cross a threshold from N-limitation to N-saturation. The most acute changes may occur in forests where base cations are derived principally from atmospheric inputs.

Perakis, Steven S.; Maguire, Douglas A.; Bullen, Thomas D.; Cromack, Kermit; Waring, Richard H.; Boyle, James R.

2006-01-01

411

Detection and quantification of some plant growth regulators in a seaweed-based foliar spray employing a mass spectrometric technique sans chromatographic separation.  

PubMed

The sap expelled from the fresh harvest of Kappaphycus alvarezii , a red seaweed growing in tropical waters, has been reported to be a potent foliar spray. Tandem mass spectrometry of various organic extracts of the sap confirmed the presence of the plant growth regulators (PGRs) indole 3-acetic acid, gibberellin GA(3), kinetin, and zeatin. These PGRs were quantified in fresh state and after 1 year of storage by ESI-MS without recourse to chromatographic separation. Quantification was validated against HPLC data. The results may be useful in correlating with the efficacy of the sap. The methodology was extended to two other seaweeds. The method developed is convenient and precise and may find application in other agricultural formulations containing these growth hormones. PMID:20355716

Prasad, Kamalesh; Das, Arun Kumar; Oza, Mihir Deepak; Brahmbhatt, Harshad; Siddhanta, Arup Kumar; Meena, Ramavatar; Eswaran, Karuppanan; Rajyaguru, Mahesh Rameshchandra; Ghosh, Pushpito Kumar

2010-04-28

412

Growth rate of ?-calcium sulfate hemihydrate in K–Ca–Mg–Cl–H 2O systems at elevated temperature  

Microsoft Academic Search

Kinetics of calcium sulfate hemihydrate (HH) crystal growth plays an important role in mineralization of calcium sulfate phases in nature. HH crystal growth and the conversion of calcium sulfate phases form the basis for the production and application of gypsum based building material. ?-HH crystals have been grown in 3.74M CaCl2 solutions at a fixed initial ratio of calcium to

Liuchun Yang; Zhongbiao Wu; Baohong Guan; Hailu Fu; Qingqing Ye

2009-01-01

413

Calcium regulation of keratinocyte differentiation  

PubMed Central

Calcium is the major regulator of keratinocyte differentiation in vivo and in vitro. A calcium gradient within the epidermis promotes the sequential differentiation of keratinocytes as they traverse the different layers of the epidermis to form the permeability barrier of the stratum corneum. Calcium promotes differentiation by both outside–in and inside–out signaling. A number of signaling pathways involved with differentiation are regulated by calcium, including the formation of desmosomes, adherens junctions and tight junctions, which maintain cell–cell adhesion and play an important intracellular signaling role through their activation of various kinases and phospholipases that produce second messengers that regulate intracellular free calcium and PKC activity, critical for the differentiation process. The calcium receptor plays a central role by initiating the intracellular signaling events that drive differentiation in response to extracellular calcium. This review will discuss these mechanisms.

Bikle, Daniel D; Xie, Zhongjian; Tu, Chia-Ling

2012-01-01

414

Application of plant growth regulators mitigates chlorotic foliar injury by the black pecan aphid (Hemiptera: Aphididae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Chlorotic feeding injury by the black pecan aphid, Melanocallis caryaefoliae (Davis) (Hemiptera: Aphididae), to pecan (Carya illinoinensis [Wangenh.] K. Koch) foliage can result in leaf senescence and abscission. The plant growth regulators chlorforfenuron (CPPU), gibberellic acid (GA3) and aminoet...

415

Crenate broomrape control in pea by foliar application of benzothiadiazole (BTH)  

Microsoft Academic Search

Parasitic plants are becoming a severe constraint on major agricultural crops in Mediterranean and tropical countries and\\u000a the efficacy of available means of control is minimal. The problem is particularly severe in field pea, which is very sensitive\\u000a to standard glyphosate treatments and in which little resistance has been identified. Systemic Acquired Resistance (SAR) has\\u000a proven to be effective as

A. Pérez-de-Luque; J. V. Jorrín; D. Rubiales

2004-01-01

416

The influence of post-veraison foliar potassium applications on table grape quality  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sugar concentration and skin color (for pigmented table grape cultivars) are primary indicators of maturity and are important for marketing purposes. Treatments that accelerate sugar and pigment development enable earlier harvest. Early harvest not only improves marketing, it reduces risks of losses...

417

INVESTIGATIONS OF COLORADO POTATO BEETLE MORTALITY FOLLOWING FOLIAR APPLICATIONS OF BEAUVERIA BASSIANA  

Technology Transfer Automated Retrieval System (TEKTRAN)

The fungus Beauveria bassiana (Bb) has the potential to kill Colorado potato beetle larvae within a few days after infection. However, under suboptimal conditions, (e.g., during hot weather), pathogenesis is slowed, allowing the beetles to complete larval development and enter the soil to pupate. Li...

418

Effect of glyphosate application on foliar diseases in glyphosate-tolerant alfalfa  

Technology Transfer Automated Retrieval System (TEKTRAN)

Glyphosate, the active ingredient in Roundup herbicide, inhibits 5-enol-pyruvyl shikimate 3-phophate synthase (EPSPS), an enzyme found in plants, fungi, and bacteria. Plants engineered for glyphosate tolerance with a glyphosate-insensitive EPSPS take up and translocate the herbicide throughout the p...

419

Fabrication and Evaluation of Ceramic Implant Materials for Replacement of Teeth and Bone - Mechanical Strength Testing of Highly Porous Calcium Aluminate Ceramics.  

National Technical Information Service (NTIS)

Porous calcium aluminate ceramics have been considered for applications as structural materials in orthopedic and dental prostheses. Calcium aluminate specimens varying in chemical composition from 23 to 34 weight percent CaO and varying in amount of poro...

S. F. Hulbert J. J. Klawitter C. N. Wilson

1971-01-01

420

Stochastic calcium mechanisms cause dendritic calcium spike variability.  

PubMed

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

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

2013-10-01

421

Nutrition in calcium nephrolithiasis  

PubMed Central

Idiopathic calcium nephrolithiasis is a multifactorial disease with a complex pathogenesis due to genetic and environmental factors. The importance of social and health effects of nephrolithiasis is further highlighted by the strong tendency to relapse of the disease. Long-term prospective studies show a peak of disease recurrence within 2–3 years since onset, 40-50% of patients have a recurrence after 5 years and more than 50-60% after 10 years. International nutritional studies demonstrated that nutritional habits are relevant in therapy and prevention approaches of nephrolithiasis. Water, right intake of calcium, low intake of sodium, high levels of urinary citrate are certainly important for the primary and secondary prevention of nephrolithiasis. In this review is discussed how the correction of nutritional mistakes can reduce the incidence of recurrent nephrolithiasis.

2013-01-01

422

Chemistry misconceptions associated with understanding calcium and phosphate homeostasis.  

PubMed

Successful learning of many aspects in physiology depends on a meaningful understanding of fundamental chemistry concepts. Two conceptual diagnostic questions measured student understanding of the chemical equilibrium underlying calcium and phosphate homeostasis. One question assessed the ability to predict the change in phosphate concentration when calcium ions were added to a saturated calcium phosphate solution. Fifty-two percent of the students correctly predicted that the phosphate concentration would decrease in accord with the common ion effect. Forty-two percent of the students predicted that the phosphate concentration would not change. Written explanations showed that most students failed to evoke the idea of competing chemical equilibria. A second question assessed the predicted change in calcium concentration after solid calcium phosphate was added to a saturated solution. Only 11% of the students correctly predicted no change in calcium concentration; 86% of the students predicted an increase, and many based their prediction on a mistaken application of Le Chatelier's principle to heterogeneous equilibria. These results indicate that many students possess misconceptions about chemical equilibrium that may hamper understanding of the processes of calcium and phosphate homeostasis. Instructors can help students gain greater understanding of these physiochemical phenomena by adopting strategies that enable students achieve more accurate conceptions of chemical equilibria. PMID:19948683

Cliff, William H

2009-12-01

423

Chemistry misconceptions associated with understanding calcium and phosphate homeostasis  

NSDL National Science Digital Library

Successful learning of many aspects in physiology depends on a meaningful understanding of fundamental chemistry concepts. Two conceptual diagnostic questions measured student understanding of the chemical equilibrium underlying calcium and phosphate homeostasis. One question assessed the ability to predict the change in phosphate concentration when calcium ions were added to a saturated calcium phosphate solution. Fifty-two percent of the students correctly predicted that the phosphate concentration would decrease in accord with the common ion effect. Forty-two percent of the students predicted that the phosphate concentration would not change. Written explanations showed that most students failed to evoke the idea of competing chemical equilibria. A second question assessed the predicted change in calcium concentration after solid calcium phosphate was added to a saturated solution. Only 11% of the students correctly predicted no change in calcium concentration; 86% of the students predicted an increase, and many based their prediction on a mistaken application of Le Chatelier's principle to heterogeneous equilibria. These results indicate that many students possess misconceptions about chemical equilibrium that may hamper understanding of the processes of calcium and phosphate homeostasis. Instructors can help students gain greater understanding of these physiochemical phenomena by adopting strategies that enable students achieve more accurate conceptions of chemical equilibria.

William H. Cliff (Niagara University Biology)

2009-12-01

424

Assay for calcium channels  

Microsoft Academic Search

This chapter focuses on biochemical assays for Ca\\/sup 2 +\\/-selective channels in electrically excitable membranes which are blocked in electrophysiological and pharmacological experiments by verapamil, 1,4-dihydropyridines, diltiazen (and various other drugs), as well as inorganic di- or trivalent cations. The strategy employed is to use radiolabeled 1,4-dihydropyridine derivatives which block calcium channels with EDââ values in the nanomolar range. Although

H. Glossmann; D. R. Ferry

1985-01-01

425

Native Environment Modulates Leaf Size and Response to Simulated Foliar Shade across Wild Tomato Species  

PubMed Central

The laminae of leaves optimize photosynthetic rates by serving as a platform for both light capture and gas exchange, while minimizing water losses associated with thermoregulation and transpiration. Many have speculated that plants maximize photosynthetic output and minimize associated costs through leaf size, complexity, and shape, but a unifying theory linking the plethora of observed leaf forms with the environment remains elusive. Additionally, the leaf itself is a plastic structure, responsive to its surroundings, further complicating the relationship. Despite extensive knowledge of the genetic mechanisms underlying angiosperm leaf development, little is known about how phenotypic plasticity and selective pressures converge to create the diversity of leaf shapes and sizes across lineages. Here, we use wild tomato accessions, collected from locales with diverse levels of foliar shade, temperature, and precipitation, as a model to assay the extent of shade avoidance in leaf traits and the degree to which these leaf traits correlate with environmental factors. We find that leaf size is correlated with measures of foliar shade across the wild tomato species sampled and that leaf size and serration correlate in a species-dependent fashion with temperature and precipitation. We use far-red induced changes in leaf length as a proxy measure of the shade avoidance response, and find that shade avoidance in leaves negatively correlates with the level of foliar shade recorded at the point of origin of an accession. The direction and magnitude of these correlations varies across the leaf series, suggesting that heterochronic and/or ontogenic programs are a mechanism by which selective pressures can alter leaf size and form. This study highlights the value of wild tomato accessions for studies of both morphological and light-regulated development of compound leaves, and promises to be useful in the future identification of genes regulating potentially adaptive plastic leaf traits.

Filiault, Daniele L.; Kumar, Ravi; Jimenez-Gomez, Jose M.; Schrager, Amanda V.; Park, Daniel S.; Peng, Jie; Sinha, Neelima R.; Maloof, Julin N.

2012-01-01

426

Native environment modulates leaf size and response to simulated foliar shade across wild tomato species.  

PubMed

The laminae of leaves optimize photosynthetic rates by serving as a platform for both light capture and gas exchange, while minimizing water losses associated with thermoregulation and transpiration. Many have speculated that plants maximize photosynthetic output and minimize associated costs through leaf size, complexity, and shape, but a unifying theory linking the plethora of observed leaf forms with the environment remains elusive. Additionally, the leaf itself is a plastic structure, responsive to its surroundings, further complicating the relationship. Despite extensive knowledge of the genetic mechanisms underlying angiosperm leaf development, little is known about how phenotypic plasticity and selective pressures converge to create the diversity of leaf shapes and sizes across lineages. Here, we use wild tomato accessions, collected from locales with diverse levels of foliar shade, temperature, and precipitation, as a model to assay the extent of shade avoidance in leaf traits and the degree to which these leaf traits correlate with environmental factors. We find that leaf size is correlated with measures of foliar shade across the wild tomato species sampled and that leaf size and serration correlate in a species-dependent fashion with temperature and precipitation. We use far-red induced changes in leaf length as a proxy measure of the shade avoidance response, and find that shade avoidance in leaves negatively correlates with the level of foliar shade recorded at the point of origin of an accession. The direction and magnitude of these correlations varies across the leaf series, suggesting that heterochronic and/or ontogenic programs are a mechanism by which selective pressures can alter leaf size and form. This study highlights the value of wild tomato accessions for studies of both morphological and light-regulated development of compound leaves, and promises to be useful in the future identification of genes regulating potentially adaptive plastic leaf traits. PMID:22253737

Chitwood, Daniel H; Headland, Lauren R; Filiault, Daniele L; Kumar, Ravi; Jiménez-Gómez, José M; Schrager, Amanda V; Park, Daniel S; Peng, Jie; Sinha, Neelima R; Maloof, Julin N

2012-01-12

427

Calcium bioavailability and kinetics of calcium ascorbate and calcium acetate in rats.  

PubMed

The objective was to investigate the bioavailability and mechanism of calcium absorption of calcium ascorbate (ASC) and calcium acetate (AC). A series of studies was performed in adult Sprague-Dawley male rats. In the first study, each group of rats (n = 10/group) was assigned to one of the five test meals labeled with (45)Ca: (i) 25 mg calcium as heated ASC or (ii) unheated ASC, (iii) 25 mg calcium as unheated AC, (iv) 3.6 mg Ca as unheated ASC, or (v) unheated AC. Femur uptake indicated better calcium bioavailability from ASC than AC at both calcium loads. A 5-min heat treatment partly reduced bioavailability of ASC. Kinetic studies were performed to further investigate the mechanism of superior calcium bioavailability from ASC. Two groups of rats (n = 10/group) received oral doses of 25 mg Ca as ASC or AC. Each dose contained 20 micro Ci (45)Ca. Two additional groups of rats (n = 10/group) received an intravenous injection (iv) of 10 micro Ci (45)Ca after receiving an unlabeled oral dose of 25 mg calcium as ASC or AC. Sequential blood samples were collected over 48 hrs. Urine and fecal samples were collected every 12 hrs for 48 hrs and were analyzed for total calcium and (45)Ca content. Total calcium and (45)Ca from serum, urine, and feces were fitted by a compartment kinetics model with saturable and nonsaturable absorption pathways by WinSAAM (Windows-based Simulation Analysis and Modeling). The difference in calcium bioavailability between the two salts was due to differences in saturable rather than passive intestinal absorption and not to endogenous secretion or calcium deposition rate. The higher bioavailability of calcium ascorbate was due to a longer transit time in the small intestine compared with ASC. PMID:14709775

Cai, Jianwei; Zhang, Qinmin; Wastney, Meryl E; Weaver, Connie M

2004-01-01

428

[Paramagnetic calcium melanins].  

PubMed

Treatment of catechol, pyrogallol, DOPA, dopamine, norepinephrine, and natural polyhydroxy-1,4-naphthoquinone echinochrome by aqueous solution of potassium superoxide (KO2) in the presence of CaCl2 leads to the formation of water-insoluble dark pigments with stable paramagnetic properties ("calcium melanins"). In control experiments in the same procedure without Ca2+, the pigments were not formed. EPR spectra of the calcium melanins had little difference from each other and from known melanins in shape, line width, and the g factor about 2,004. Addition of EDTA water solution to dried paramagnetic pigments leads to their fast dissolving and disappearing of EPR signal. Formation of similar polymers is also observed during autoxidation of o-diphenols in Ca(2+)-containing alkaline buffer solution, however, this process takes a few days instead of few seconds in the presence of KO2. Thus, calcium (and other divalent cation M2+) can consider as a key structural element in formation of M(2+)-catecholate paramagnetic Polymer. We assume the existence of two types of paramagnetic centers in melanin-like polymer: M(2+)-stabilized o-semiquinone radical or bi-radical complex containing o-semiquinone and superoxide anion radicals, stabilized by M2+. PMID:23650854

Lebedev, A V; Ivanova, M V; Timoshin, A A; Ruuge, E K

429

Changes of intracellular free calcium following mechanical injury in a spinal cord slice preparation.  

PubMed

Intracellular calcium ions are, in addition to free radicals, an important mediator of tissue destruction following traumatic injury to the spinal cord. In vivo measurements of calcium in the interstitial space and in the tissue suggest the occurrence of a posttraumatic shift of calcium from the extracellular to the intracellular compartment at the injury site. No information is, however, available on the posttraumatic changes of calcium in the intracellular compartment, where the ion exerts its crucial messenger function. We developed an in vitro model of local traumatic spinal injury, using a spinal cord slice preparation, allowing us to investigate injury-related changes of intracellular free calcium. The injury consisted of the impact of a small needle, and intracellular free calcium was measured with fura-2. Application of the injury at different places within the gray matter caused a transient and reproducible increase in the fura-2 fluorescence ratio. This injury-induced ratio increase was largely, but not completely, suppressed under zero extracellular calcium conditions. It was also largely depressed in the presence of high extracellular potassium and in the absence of extracellular sodium. It was modestly depressed by the calcium channel blocker nifedipin, by the calcium release channel blocker dantrolene, and by the gap junction blockers halothane and octanol. The calcium channel blocker flunarizine, the N-methyl D-aspartate (NMDA)-receptor-channel blocker MK-801 and the endoplasmic reticulum calcium-ATPase blocker thapsigargin had no effect. The experiments suggest that injury is associated with an increase in intracellular free calcium that is mediated by calcium influx, in part via L-type calcium channels. They furthermore give evidence that sodium influx and gap junctions are involved in these injury-associated changes of intracellular free calcium. PMID:9007541

Leybaert, L; de Hemptinne, A

1996-12-01

430

Calcium entry through nicotinic receptor channels and calcium channels in cultured rat superior cervical ganglion cells.  

PubMed Central

1. Patch-clamp techniques in conjunction with indo-1 fluorescent measurements were used to measure increases in intracellular free calcium concentration and membrane conductance induced by the activation of nicotinic and calcium channels in cultured rat sympathetic neurons. 2. Under voltage-clamp conditions, pressure application of the nicotinic agonist DMPP (1,1-dimethyl-4-phenylpiperazinium iodide, 100 microM, 100 ms) increased [Ca2+]i by 193 +/- 26 nM at a clamp potential of -60 mV. This was accompanied by an inward current of -4.53 +/- 0.89 nA, giving a mean ratio of the delta (Ca2+]i to the total inward charge transfer of 42.7 nmoles per litre of free calcium per nanocoulomb of charge (M/q ratio). 3. The DMPP-induced current and associated delta [Ca2+]i were reduced by mecamylamine (100 nM-10 microM) but were unaffected by alpha-bungarotoxin (100 nM) or cadmium (100 microM). 4. The M/q ratio was not affected by the holding potential (from -80 to -40 mV) but was a function of the external calcium concentration. 5. The M/q ratio was reduced by increasing the intracellular calcium buffering capacity and increased by heparin but not affected by ryanodine or by depletion of the caffeine-sensitive calcium store. 6. Under the same recording conditions, we quantified the increase in [Ca2+]i associated with activation of the voltage-dependent calcium current. On average at -60 mV, the M/q ratio of this highly calcium-selective permeability was 1961 mM nC-1, which is 46 times that obtained for the nicotinic channel. 7. Assuming constant-field theory, ion-substitution experiments suggest that in 2.5 mM external calcium, the permeability sequence for the nicotinic conductance was Cs+ < Li+ < Na+ < K+ < Ca2+. 8. We conclude that the nicotinic channels in rat sympathetic neurones are significantly permeant to Ca2+ and that the influx of Ca2+ through these channels is the principal cause of the rise in [Ca2+]i seen under voltage clamp.

Trouslard, J; Marsh, S J; Brown, D A

1993-01-01

431

Regulation of cellular calcium metabolism and calcium transport by calcitonin  

Microsoft Academic Search

Summary Calcitonin was studied in isolated kidney cells and in isolated mitochondria. A concentration of 10 ng\\/ml of synthetic calcitonin increases the cellular accumulation of45Ca and the total cell calcium. The mitochondrial pool is increased several-fold. Kinetic analysis of the data shows that although the total cellular exchangeable calcium pool is enlarged, calcium influx and efflux are significantly depressed by

André B. Borle

1975-01-01

432

A calcium conducting channel akin to a calcium pump  

Microsoft Academic Search

Summary  Calcium conducting channels were studied in blebs of sarcoplasmic reticulum described by Stein & Palade (1988). The calcium channels had at least three conductance states (70 pS, 50 pS and 37 pS) and were weakly selective for calcium ions, with a permeability ratio Ca2+ to K+ of about 3.4. The open probability of the channel was strongly voltage dependent, decreasing

Jinsong Wang; John M. Tang; Robert S. Eisenberg

1992-01-01

433

Effect of strontium ions substitution on gene delivery related properties of calcium phosphate nanoparticles  

Microsoft Academic Search

Gene therapy has been considered a strategy for delivery of therapeutic nucleic acids to a specific site. Calcium phosphates\\u000a are one gene delivery vector group of interest. However, low transfection efficiency has limited the use of calcium phosphate\\u000a in gene delivery applications. Present work aims at studying the fabrication of strontium substituted calcium phosphate nanoparticles\\u000a with improved gene delivery related

A. HanifiM; M. H. Fathi; H. Mir Mohammad Sadeghi

2010-01-01

434

Calcium Isotope Systematics During Development of the Domestic Chicken (Gallus gallus)  

NASA Astrophysics Data System (ADS)

Calcium isotope distributions have been recognized as showing systematic and predictable fractionation in nature. However, most of the observed calcium isotope fractionation to date is due to biological processes. The presence of abundant amounts of calcium in mineralized tissues makes the isotopic system of calcium particularly valuable in biological and paleobiological questions involving biomineralization. In order to apply calcium isotope systematics to paleobiological questions the changes in the calcium isotope signatures of mineralized tissue in modern animals should be studied. My study observed the domestic chicken (Gallus gallus) through embryologic ontogeny. This was accomplished by obtaining fertilized eggs staged in a growth series from day 12 to day 20. The eggs were dissected and shell, embryonic bone, albumen, and yolk were analyzed in order to characterize the calcium isotopic composition of the individual components over the course of the growth series. Several systematic changes in the isotopic signatures of various tissues were observed during the course of the development of the embryos. In general, mineralization in biological systems preferentially partitions the lighter isotopes of calcium into hard parts. As a result of this fractionation during mineralization, partitioning of light isotopes of calcium into the mineralized tissues may result in residual tissues being enriched in the heavier isotopes as ontogeny progresses. Better understanding of the behavior of calcium in modern biological systems will improve its application to fossils and expand the number of paleobiological and evolutionary questions that can be addressed using calcium isotopic data.

Wheatley, P. V.

2003-12-01

435

CALCIUM SIGNALLING AND CALCIUM TRANSPORT IN BONE DISEASE  

PubMed Central

Calcium transport and calcium signalling mechanisms in bone cells have, in many cases, been discovered by study of diseases with disordered bone metabolism. Calcium matrix deposition is driven primarily by phosphate production, and disorders in bone deposition include abnormalities in membrane phosphate transport such as in chondrocalcinosis, and defects in phosphate-producing enzymes such as in hypophosphatasia. Matrix removal is driven by acidification, which dissolves the mineral. Disorders in calcium removal from bone matrix by osteoclasts cause osteopetrosis. On the other hand, although bone is central to management of extracellular calcium, bone is not a major calcium sensing organ, although calcium sensing proteins are expressed in both osteoblasts and osteoclasts. Intracellular calcium signals are involved in secondary control including cellular motility and survival, but the relationship of these findings to specific diseases is not clear. Intracellular calcium signals may regulate the balance of cell survival versus proliferation or anabolic functional response as part of signalling cascades that integrate the response to primary signals via cell stretch, estrogen, tyrosine kinase, and tumor necrosis factor receptors

Blair, H.C.; Schlesinger, P.H.; Huang, Christopher L.-H.; Zaidi, M.

2010-01-01

436

Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species.  

PubMed

Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. PMID:15809106

Novak, K; Schaub, M; Fuhrer, J; Skelly, J M; Hug, C; Landolt, W; Bleuler, P; Kräuchi, N

2005-07-01

437

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

Code of Federal Regulations, 2013 CFR

... 3 2013-04-01 2013-04-01 false Calcium pantothenate, calcium chloride double salt. 172.330 Section 172...Dietary and Nutritional Additives § 172.330 Calcium pantothenate, calcium chloride double salt....

2013-04-01

438

Secondary calcium solid electrolyte high temperature battery  

NASA Astrophysics Data System (ADS)

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

Sammells, A. F.; Schumacher, B.

1986-01-01

439

Calcium signaling in Xenopus oocyte.  

PubMed

Knowledge about calcium signaling had increased thanks to the development and manipulation of various cell models. Among all of these prototypes, Xenopus laevis oocyte appears to be one of the most relevant. The understanding of the role of calcium during oocyte oogenesis, maturation and fertilization is facilitated by the big size of the cell but also by using imaging and electrophysiological approaches. So, this chapter presents how recordings of calcium-activated chloride channels and Store-Operated Calcium Channels activities lead to demonstrate the implication of the MPF in the uncoupling between intracellular calcium releasing and capacitative calcium entry. Moreover, it will help us to understand the several reorganizations happening consequently to the pH variations of maturation or just at the moment of fertilization. PMID:22453984

Marin, Matthieu

2012-01-01

440

Organization of early development by calcium patterns  

Microsoft Academic Search

Summary This survey focuses on early or primitive developmental phenomena for which the location of a steady high calcium region or the direction of a calcium wave is critical and calcium is more than a trigger. It starts with the long studied roles of calcium in fucoid eggs and in Dictyostelium and progresses to newer work on high calcium regions

Lionel F. Jaffe

1999-01-01

441

Calcium-activated potassium channels  

Microsoft Academic Search

Calcium-activated potassium channels are fundamental regulators of neuronal excitability, participating in interspike interval and spike-frequency adaptation. For large-conductance calcium-activated potassium (BK) channels, recent experiments have illuminated the fundamental biophysical mechanisms of gating, demonstrating that BK channels are voltage gated and calcium modulated. Structurally, BK channels have been shown to possess an extracellular amino-terminal domain, different from other potassium channels. Domains

Cecilia Vergara; Ramon Latorre; Neil V Marrion; John P Adelman

1998-01-01

442

INTEGUMENTARY LOSS OF CALCIUM.: 839  

Microsoft Academic Search

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

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

1978-01-01

443

Peroral cholegraphy with ipodate calcium  

Microsoft Academic Search

Ipodate calcium was given orally to 246 patients. It outlined the extrahepatic ducts and gall bladder in their natural states in 177 patients, 71.9%. The delineation of the gall bladder was considered good or excellent in 176 patients, 71.5%. Reactions, all of a minor nature, occurred in 31 patients, 12.6% of all patients examined radiographically with ipodate calcium. Ipodate calcium

Alexander Lewitan; Jose Felix Garcia

1965-01-01

444

Noninvasive Quantification of Coronary Calcium  

Microsoft Academic Search

Calcium in the form of hydroxyapatite (HA) is regarded as a known marker for the presence of atherosclerotic lesions of the\\u000a coronary arteries. Several studies have demonstrated that the risk for coronary events is associated and strongly correlated\\u000a with the amount of coronary calcium (1,2). The absence of coronary calcium does almost certainly imply the absence of coronary artery disease

Stefan Ulzheimer; Kaiss Shanneik; Willi A. Kalender

445

Calcium Deficiency Alters Chorda Tympani Nerve Responses to Oral Calcium Chloride  

Microsoft Academic Search

Inoue, M. and M. G. Tordoff.Calcium deficiency alters chorda tympani nerve responses to oral calcium chloride.PHYSIOL BEHAV 63(2) 297–303, 1998.—As a preliminary examination of the influence of calcium deficiency on gustatory sensitivity to calcium, we recorded electrophysiological responses of the chorda tympani nerve of calcium-replete and calcium-deprived rats. Relative to rats fed calcium-replete diet, rats fed low calcium diet had

Masashi Inoue; Michael G Tordoff

1998-01-01

446

Changes in conifer and deciduous forest foliar and forest floor chemistry and basal area tree growth across a nitrogen (N) deposition gradient in the northeastern US  

Microsoft Academic Search

We evaluated foliar and forest floor chemistry across a gradient of N deposition in the Northeast at 11 red spruce (Picea rubens Sarg.) sites in 1987\\/1988 and foliar and forest floor chemistry and basal area growth at six paired spruce and deciduous sites in 1999. The six red spruce plots were a subset of the original 1987\\/1988 spruce sites. In

Johnny L. Boggs; Steven G. McNulty; Linda H. Pardo

2007-01-01

447

Integrated biological control of bacterial speck and spot of tomato under field conditions using foliar biological control agents and plant growth-promoting rhizobacteria  

Microsoft Academic Search

Integration of foliar bacterial biological control agents and plant growth promoting rhizobacteria (PGPR) was investigated to determine whether biological control of bacterial speck of tomato, caused by Pseudomonas syringae pv. tomato, and bacterial spot of tomato, caused by Xanthomonas campestris pv. vesicatoria and Xanthomonas vesicatoria, could be improved. Three foliar biological control agents and two selected PGPR strains were employed

P. Ji; H. L. Campbell; J. W. Kloepper; J. B. Jones; T. V. Suslow; M. Wilson

2006-01-01

448

Effectiveness of different sources of manganese foliar sprays in alleviating manganese deficiency of Lupinus angustifolius L. grown on manganese deficient soils in western Australia  

Microsoft Academic Search

Responses of narrow?leafed sweet lupins (Lupinus angustifolius L.) to foliar sprays of different sources of manganese (Mn) were compared in field experiments in three years at six sites in Western Australia. The relative effectiveness of manganese chelate (EDTA; 14% Mn) and manganese sulfate (25% Mn) applied as foliar sprays for alleviating Mn deficiency of lupins was assessed. Each source was

R. F. Brennam

1996-01-01

449

Integrated biological control of bacterial speck and spot of tomato under Weld conditions using foliar biological control agents and plant growth-promoting rhizobacteria  

Microsoft Academic Search

Integration of foliar bacterial biological control agents and plant growth promoting rhizobacteria (PGPR) was investigated to deter- mine whether biological control of bacterial speck of tomato, caused by Pseudomonas syringae pv. tomato, and bacterial spot of tomato, caused by Xanthomonas campestris pv. vesicatoria and Xanthomonas vesicatoria, could be improved. Three foliar biological control agents and two selected PGPR strains were

P. Ji; H. L. Campbell; J. W. Kloepper; J. B. Jones; T. V. Suslow; M. Wilson

2006-01-01

450

CALCIUM BINDING TO INTESTINAL MEMBRANES  

PubMed Central

Flame photometry reveals that glutaraldehyde and buffer solutions in routine use for electron microscopy contain varying amounts of calcium. The presence of electron-opaque deposits adjacent to membranes in a variety of tissues can be correlated with the presence of calcium in the fixative. In insect intestine (midgut), deposits occur adjacent to apical and lateral plasma membranes. The deposits are particularly evident in tissues fixed in glutaraldehyde without postosmication. They are also observed in osmicated tissue if calcium is added to wash and osmium solutions. Deposits are absent when calcium-free fixatives are used, but are present when traces of CaCl2 (as low as 5 x 10-5 M) are added. The deposits occur at regular intervals along junctional membranes, providing images strikingly similar to those obtained by other workers who have used pyroantimonate in an effort to localize sodium. Other divalent cations (Mg++, Sr++, Ba++, Mn++, Fe++) appear to substitute for calcium, while sodium, potassium, lanthanum, and mercury do not. After postfixing with osmium with calcium added, the deposits can be resolved as patches along the inner leaflet of apical and lateral plasma membranes. The dense regions may thus localize membrane constituents that bind calcium. The results are discussed in relation to the role of calcium in control of cell-to-cell communication, intestinal calcium uptake, and the pyroantimonate technique for ion localization.

Oschman, James L.; Wall, Betty J.

1972-01-01

451

Cardiovascular effects of calcium supplements.  

PubMed

Calcium supplements reduce bone turnover and slow the rate of bone loss. However, few studies have demonstrated reduced fracture incidence with calcium supplements, and meta-analyses show only a 10% decrease in fractures, which is of borderline statistical and clinical significance. Trials in normal older women and in patients with renal impairment suggest that calcium supplements increase the risk of cardiovascular disease. To further assess their safety, we recently conducted a meta-analysis of trials of calcium supplements, and found a 27%-31% increase in risk of myocardial infarction, and a 12%-20% increase in risk of stroke. These findings are robust because they are based on pre-specified analyses of randomized, placebo-controlled trials and are consistent across the trials. Co-administration of vitamin D with calcium does not lessen these adverse effects. The increased cardiovascular risk with calcium supplements is consistent with epidemiological data relating higher circulating calcium concentrations to cardiovascular disease in normal populations. There are several possible pathophysiological mechanisms for these effects, including effects on vascular calcification, vascular cells, blood coagulation and calcium-sensing receptors. Thus, the non-skeletal risks of calcium supplements appear to outweigh any skeletal benefits, and are they appear to be unnecessary for the efficacy of other osteoporosis treatments. PMID:23857224

Reid, Ian R

2013-07-05

452

110mAg root and foliar uptake in vegetables and its migration in soil.  

PubMed

110mAg, as a radionuclide of corrosion products in water-cooled nuclear reactors, was detected in the liquid effluents of Guangdong Daya Bay Nuclear Power Station (GNPS) of Daya Bay under normal operation conditions. Experiments on a simulated terrestrial agricultural ecosystem were carried out using the pot experiment approach. The most common plants in Hong Kong and the South China vegetable gardens such as lettuce, Chinese spinach, kale, carrot, pepper, eggplant, bean, flowering cabbage, celery, European onion and cucumber were selected for (110m)Ag root and foliar uptake tests. The results show that carrot, kale and flowering cabbage have the greatest values of soil to plant transfer factor among the vegetables, while(110m)Ag can be transferred to Chinese spinach via foliar uptake. Flowering cabbage, the most popular leafy vegetable locally, could be used as a biomonitor for the radioisotope contamination in vegetables. Soil column and adsorption tests were also carried out to study the leaching ability and distribution coefficient (K(d)) of (110m)Ag in the soil. The results show that most of the radionuclide was adsorbed in the top 1 cm of soil regardless of the pH value. The K(d) was also determined. PMID:12573862

Shang, Z R; Leung, J K C

2003-01-01

453

Effect of foliar disease on the epiphytic yeast communities of creeping bentgrass and tall fescue.  

PubMed

The effect of mechanical wounding or foliar diseases caused by Sclerotinia homoeocarpa or Rhizoctonia solani on the epiphytic yeast communities on creeping bentgrass and tall fescue were determined by leaf washing and dilution plating. Total yeast communities on healthy bentgrass and tall fescue leaves ranged from 7.9 x 103 to 1.4 x 105 CFU.cm-2 and from 2.4 x 103 to 1.6 x 104 CFU.cm-2, respectively. Mechanically wounded leaves (1 of 2 trials) and leaves with disease lesions (11 of 12 trials) supported significantly larger communities of phylloplane yeasts. Total yeast communities on S. homoeocarpa infected or R. solani infected bentgrass leaves were 3.6-10.2 times and 6.2-6.4 times larger, respectively, than the communities on healthy leaves. In general, healthy and diseased bentgrass leaves supported larger yeast communities than healthy or diseased tall fescue leaves. We categorized the majority of yeasts as white-pigmented species, including Cryptococcus laurentii, Cryptococcus flavus, Pseudozyma antarctica, Pseudozyma aphidis, and Pseudozyma parantarctica. The percentage of pink yeasts in the total yeast community ranged from 2.6% to 9.9% on healthy leaves and increased to 32.0%-44.7% on S. homoeocarpa infected leaves. Pink-pigmented yeasts included Rhodotorula glutinis, Rhodotorula mucilaginosa, Sakaguchia dacryoidea, and Sporidiobolus pararoseus. Foliar disease significantly affected community size and composition of epiphytic yeasts on bentgrass and tall fescue. PMID:15644900

Allen, Tom W; Quayyum, Habib A; Burpee, Leon L; Buck, James W

2004-10-01

454

Effects of simulated sulfuric acid rain on yield, growth, and foliar injury of several crops  

SciTech Connect

This study was designed to reveal patterns of response of major United States crops to sulfuric acid rain. Potted plants were grown in field chambers and exposed to simulated sulfuric acid rain (pH 3.0, 3.5 or 4.0) or to a control rain (pH 5.6). At harvest, the weights of the marketable portion, total aboveground portion and roots were determined for 28 crops. Of these, marketable yield production was inhibited for 5 crops (radish, beet, carrot, mustard greens, broccoli), stimulated for 6 crops (tomato, green pepper, strawberry, alfalfa, orchardgrass, timothy), and ambiguously affected for 1 crop (potato). In addition, stem and leaf production of sweet corn was stimulated. Visible injury of tomatoes might have decreased their marketability. No statistically significant effects on yield were observed for the other 15 crops. The results suggest that the likelihood of yield being affected by acid rain depends on the part of the plant utilized, as well as on species. Effects on the aboveground portions of crops and on roots are also presented. Plants were regularly examined for foliar injury associated with acid rain. Of the 35 cultivars examined, the foliage of 31 was injured at pH 3.0, 28 at pH 3.5, and 5 at pH 4.0. Foliar injury was not generally related to effects on yield. However, foilar injury of swiss chard, mustard greens and spinach was severe enough to adversely affect marketability.

Lee, J.J.; Neely, G.E.; Perrigan, S.C.; Grothaus, L.C.

1980-10-01

455

Endohyphal bacterium enhances production of indole-3-acetic Acid by a foliar fungal endophyte.  

PubMed

Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions. PMID:24086270

Hoffman, Michele T; Gunatilaka, Malkanthi K; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A Elizabeth

2013-09-24

456

Foliar response and growth of apple trees following exposure to ozone and sulfur dioxide  

SciTech Connect

Three cultivars of greenhouse-grown apple trees (Malus domestica, Borkh.) were fumigated for single, 4-hour exposures with ozone (O/sub 3/) and/or sulfur dioxide (SO/sub 2/) at 0.40 and 0.80 ppm. Fumigations were performed in a plexiglass chamber situated within a controlled environment walk-in growth chamber. All 3 cultivars responded to treatments in a similar manner. When applied separately both gases induced characteristic foliar injury. In general, apple trees were more sensitive to 0.40 ppm O/sub 3/ than to 0.40 ppm SO/sub 2/; but they responded similarly to 0.80 ppm O/sub 3/ or SO/sub 2/. Foliar injury, leaf abscission, and shoot growth reduction were greatest when 0.80 ppm O/sub 3/ and 0.80 ppm SO/sub 2/ were combined. The data showed a less-than additive response when the 2 pollutants were combined; a response due, in part, to the high amount of injury induced by single pollutants at these concentrations. All O/sub 3/ and/or SO/sub 2/ fumigations resulted in stomatal closure.

Shertz, R.D.; Kender, W.J.; Musselman, R.C.

1980-01-01

457

Foliar ozone injury on different-sized Prumus serotina Ehrh. trees  

SciTech Connect

Black cherry (Prunus serotina Ehrh.) is a common tree species in the eastern U.S. that is highly sensitive to ozone relative to other associated deciduous tree species. Because of difficulties in conducting exposure-response experiments on large trees, air pollution studies have often utilized seedlings and extrapolated the results to predict the potential response of larger forest trees. However, physiological differences between seedlings and mature forest trees may alter responses to air pollutants. A comparative study of seedling, sapling, and canopy black cherry trees was conducted to determine the response of different-sized trees to known ozone exposures and amounts of ozone uptake. Apparent foliar sensitivity to ozone, observed as a dark adaxial leaf stipple, decreased with increasing tree size. An average of 46% of seedling leaf area was symptomatic by early September, compared to 15% - 20% for saplings and canopy trees. In addition to visible symptoms, seedlings also appeared to have greater rates of early leaf abscission than larger trees. Greater sensitivity (i.e., foliar symptoms) per unit exposure with decreasing tree size was closely correlated with rates of stomatal conductance. However, after accounting for differences in stomatal conductance, sensitivity appeared to increase with tree size.

Fredericksen, T.S.; Skelly, J.M.; Steiner, K.C. [Pennsylvania State Univ., University Park, PA (United States)

1995-06-01

458

EDU and ozone protection: Foliar glycerolipids and steryl lipids in snapbean exposed to O sub 3  

SciTech Connect

Effects of ethylene diurea (EDU) on foliar lipids in snapbeans before and after a single, acute ozone exposure were assessed. Systemic treatment with EDU slightly reduced membrane lipid content in the first trifoliate leaf. EDU conferred protection against ozone-induced necrosis. Leaves of untreated controls had lost ca 50% of both galacto- (GL) and phospholipids (PL) after a 3 hr exposure to 0.4 ppm O{sub 3}, whereas EDU-treated plants showed no significant loss of foliar GL and PL. A decline in the ratio of mono- to digalactosyl-diacylglycerol (MGDG/DGDG) was associated with the loss of GL, and a decline in the ratio of linoleic to linolenic acid (18:2/18:3) associated with the loss of PL, in untreated controls. The MGDG/DGDG ratio declined only slightly and the 18:2/18:3 ratio in PL increased during O{sub 3} exposure of EDU-treated seedlings. The level of total membrane sterols, including free sterols (FS), acylated steryl glycosides (ASG) and steryl glycosides (SG), did not change during O{sub 3} exposure of either treated or untreated plants. ASG and SG increased at the expense of FS, and the ratio of stigmasterol/sitosterol increased in ASG and SG in controls. In EDU-treated plants, a small increase in SG was offset by a decrease in FS, and there was no change in the stigmasterol/sitosterol ratio in ASG, SG or FS.

Whitaker, B.D.; Lee, E.H.; Rowland, R.A. (USDA/Agricultural Research Service, Beltsville, MD (USA))

1990-05-01

459

Endohyphal Bacterium Enhances Production of Indole-3-Acetic Acid by a Foliar Fungal Endophyte  

PubMed Central

Numerous plant pathogens, rhizosphere symbionts, and endophytic bacteria and yeasts produce the important phytohormone indole-3-acetic acid (IAA), often with profound effects on host plants. However, to date IAA production has not been documented among foliar endophytes -- the diverse guild of primarily filamentous Ascomycota that live within healthy, above-ground tissues of all plant species studied thus far. Recently bacteria that live within hyphae of endophytes (endohyphal bacteria) have been detected, but their effects have not been studied previously. Here we show not only that IAA is produced in vitro by a foliar endophyte (here identified as Pestalotiopsis aff. neglecta, Xylariales), but that IAA production is enhanced significantly when the endophyte hosts an endohyphal bacterium (here identified as Luteibacter sp., Xanthomonadales). Both the endophyte and the endophyte/bacterium complex appear to rely on an L-tryptophan dependent pathway for IAA synthesis. The bacterium can be isolated from the fungus when the symbiotic complex is cultivated at 36°C. In pure culture the bacterium does not produce IAA. Culture filtrate from the endophyte-bacterium complex significantly enhances growth of tomato in vitro relative to controls and to filtrate from the endophyte alone. Together these results speak to a facultative symbiosis between an endophyte and endohyphal bacterium that strongly influences IAA production, providing a new framework in which to explore endophyte-plant interactions.

Hoffman, Michele T.; Gunatilaka, Malkanthi K.; Wijeratne, Kithsiri; Gunatilaka, Leslie; Arnold, A. Elizabeth

2013-01-01

460

Natural variations in calcium isotope composition as a monitor of bone mineral balance in humans.  

NASA Astrophysics Data System (ADS)

The skeleton is the largest reservoir of calcium in the human body and is responsible for the short term control of blood levels of this element. Accurate measurement of changes in bone calcium balance is critical to understanding how calcium metabolism responds to physiological and environmental changes and, more specifically, to diagnosing and evaluating the effectiveness of treatments for osteoporosis and other serious calcium-related disorders. It is very difficult to measure bone calcium balance using current techniques, however, because these techniques rely either on separate estimates of bone resorption and formation that are not quantitatively comparable, or on complex and expensive studies of calcium kinetics using administered isotopic tracers. This difficulty is even more apparent and more severe for measurements of short-term changes in bone calcium balance that do not produce detectable changes in bone mineral density. Calcium isotopes may provide a novel means of addressing this problem. The foundation of this isotope application is the ca. 1.3 per mil fractionation of calcium during bone formation, favoring light calcium in the bone. This fractionation results in a steady-state isotopic offset between calcium in bone and calcium in soft tissues, blood and urine. Perturbations to this steady state due to changes in the net formation or resorption of bone should be reflected in changes in the isotopic composition of soft tissues and fluids. Here we present evidence that easily detectable shifts in the natural calcium isotope composition of human urine rapidly reflect changes in bone calcium balance. Urine from subjects in a 17-week bed rest study was analyzed for calcium isotopic composition. Bed rest promotes net resorption of bone, shifting calcium from bone to soft tissues, blood and urine. The calcium isotope composition of patients in this study shifted toward lighter values during bed rest, consistent with net resorption of isotopically-light bone calcium. In contrast, little shift was seen in patients who exercised during bed rest, consistent with the expectation that exercise should inhibit bone resorption. Most intriguingly, an opposite-sense shift was seen in patients who were administered aledronate, a drug which inhibits bone resorption. We hypothesize that these patients entered a state of positive bone mineral balance despite initiation of bed rest. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism confirms that the calcium isotope composition of urine reflects changes in bone mineral balance. Calcium isotope analysis of urine and soft tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.

Skulan, J.; Anbar, A.; Thomas, B.; Smith, S.

2004-12-01

461

The oxidation of calcium sulphite by calcium nitrate  

Microsoft Academic Search

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

Andrew K Galwey; Clodagh Ettarh

1998-01-01

462

New techniques in the post?harvest treatment of apple fruits with calcium salts  

Microsoft Academic Search

Calcium penetrates apple (Malus domestica Borkh) fruits from externally applied solutions primarily through lenticels and other small discontinuities. Since the skin is the major barrier to absorption, control of storage disorders varies with skin porosity. Calcium uptake is greater at higher concentrations of solution but, in practice, risk of lenticel injury limits application rates. Incorporation of a surfactant may increase

D. S. Johnson

1979-01-01

463

A novel method to make regenerable core-shell calcium-based sorbents  

Microsoft Academic Search

A sorbent having a calcium oxide core and a clay shell was prepared and shown to be capable of reusable applications in absorption and desorption processes for carbon dioxide. The novelty of this sorbent is that only calcium carbonate and clay are used for its preparation with water as a binder. A two-step granulation procedure is used to get the

F. J. Liu; K. S. Chou; Y. K. Huang

2006-01-01

464

Of the in vivo behavior of calcium phosphate cements and glasses as bone substitutes  

Microsoft Academic Search

The use of injectable self-setting calcium phosphate cements or soluble glass granules represent two different strategies for bone regeneration, each with distinct advantages and potential applications. This study compares the in vivo behavior of two calcium phosphate cements and two phosphate glasses with different composition, microstructure and solubility, using autologous bone as a control, in a rabbit model. The implanted

E. S. Sanzana; M. Navarro; F. Macule; S. Suso; J. A. Planell; M. P. Ginebra

2008-01-01

465

21 CFR 73.1070 - Calcium carbonate.  

Code of Federal Regulations, 2013 CFR

...Specifications. Calcium carbonate shall meet the specifications for precipitated calcium carbonate in the United States Pharmacopeia XX (1980). (c) Uses and restrictions. Calcium carbonate may be safely used in amounts...

2013-04-01

466

21 CFR 182.8217 - Calcium phosphate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Calcium phosphate. 182.8217 Section 182.8217 Food...RECOGNIZED AS SAFE Nutrients § 182.8217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2013-04-01

467

21 CFR 182.1217 - Calcium phosphate.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Calcium phosphate. 182.1217 Section 182.1217 Food...Purpose GRAS Food Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2009-04-01

468

21 CFR 182.1217 - Calcium phosphate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Calcium phosphate. 182.1217 Section 182.1217 Food...Purpose GRAS Food Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2013-04-01

469

21 CFR 182.8217 - Calcium phosphate.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Calcium phosphate. 182.8217 Section 182.8217 Food...RECOGNIZED AS SAFE Nutrients § 182.8217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2009-04-01

470

21 CFR 182.8217 - Calcium phosphate.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Calcium phosphate. 182.8217 Section 182.8217 Food...RECOGNIZED AS SAFE Nutrients § 182.8217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2010-01-01

471

21 CFR 182.1217 - Calcium phosphate.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2009-04-01 true Calcium phosphate. 182.1217 Section 182.1217 Food...Purpose GRAS Food Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

2010-01-01