Single and combined effects of two trace elements (Cd and Cu) on the asexual reproduction of Aurelia sp. polyps

The symptoms of trace element deficiency arise from the combined effects of the different lesions provoked within the animal body. Since a variety of different lesions have been described, many of which affect inter-related systems, it is not surprising that diverse symptoms may arise even from the one trace element deficiency; nor that similar symptoms may be caused by deficiencies of different trace elements. The major effects of trace element deficiencies on body functions have been outlined in Table 3.2.1 (from Underwood, 1980).

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Combined effects of food supply and temperature on asexual reproduction and somatic growth of polyps of the common jellyfish Aurelia aurita s.l.

Plankton and Benthos Research ◽

10.3800/pbr.5.98 ◽

2010 ◽

Vol 5 (3) ◽

pp. 98-105 ◽

Cited By ~ 73

Author(s):

Chang-Hoon Han ◽

Shin-ichi Uye

Keyword(s):

Asexual Reproduction ◽

Food Supply ◽

Somatic Growth ◽

Aurelia Aurita ◽

Combined Effects ◽

The Common

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Microanalytical Identification of a New Zr-Nb-Fe Phase

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134259 ◽

1990 ◽

Vol 48 (2) ◽

pp. 132-133

Author(s):

O.T. Woo ◽

G.J.C. Carpenter

Keyword(s):

Trace Elements ◽

Cold Rolling ◽

Proportionality Factor ◽

Tube Material ◽

X Ray ◽

Metal Foils ◽

Arc Melting ◽

Intermetallic Particles ◽

Intermetallic Precipitates ◽

Cold Worked

To study the influence of trace elements on the corrosion and hydrogen ingress in Zr-2.5 Nb pressure tube material, buttons of this alloy containing up to 0.83 at% Fe were made by arc-melting. The buttons were then annealed at 973 K for three days, furnace cooled, followed by ≈80% cold-rolling. The microstructure of cold-worked Zr-2.5 at% Nb-0.83 at% Fe (Fig. 1) contained both β-Zr and intermetallic precipitates in the α-Zr grains. The particles were 0.1 to 0.7 μm in size, with shapes ranging from spherical to ellipsoidal and often contained faults. β-Zr appeared either roughly spherical or as irregular elongated patches, often extending to several micrometres.The composition of the intermetallic particles seen in Fig. 1 was determined using Van Cappellen’s extrapolation technique for energy dispersive X-ray analysis of thin metal foils. The method was employed to avoid corrections for absorption and fluorescence via the Cliff-Lorimer equation: CA/CB = kAB · IA/IB, where CA and CB are the concentrations by weight of the elements A and B, and IA and IB are the X-ray intensities; kAB is a proportionality factor.

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XRMF applications of a monolithic, polycapillary, focusing x-ray optic

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163666 ◽

1996 ◽

Vol 54 ◽

pp. 240-241

Author(s):

D. A. Carpenter ◽

Ning Gao ◽

G. J. Havrilla

Keyword(s):

Trace Elements ◽

Point Source ◽

Focal Spot ◽

Fluorescence Analysis ◽

X Rays ◽

Focal Distance ◽

Spot Diameter ◽

X Ray ◽

Focal Spot Diameter

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.

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Trace Elements and Iron in Human Metabolism

Biochemical Society Transactions ◽

10.1042/bst0071330a ◽

1979 ◽

Vol 7 (6) ◽

pp. 1330-1331

Author(s):

E. D. WILLS

Keyword(s):

Trace Elements ◽

Human Metabolism

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Meat and Meat Products Consumption in Italy: Contribution to Trace Elements, Heme Iron and selected B Vitamins supply

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.74.4.247 ◽

2004 ◽

Vol 74 (4) ◽

pp. 247-251 ◽

Cited By ~ 13

Author(s):

Lombardi-Boccia ◽

Lanzi ◽

Lucarini ◽

Di Lullo

Keyword(s):

Trace Elements ◽

Daily Intake ◽

Meat Products ◽

Heme Iron ◽

B Vitamins ◽

Zinc Intake ◽

Consumption Frequency ◽

Iron And Zinc ◽

Iron Heme ◽

Daily Intakes

This study was undertaken to estimate the contribution of meat and meat products consumption to the daily intakes of trace elements (Fe, Zn, Cu, Se), heme iron, and selected B vitamins (thiamine, riboflavin, niacin) in Italy. Meat and meat products were selected on the basis of their consumption frequency reported by the most recent nationwide dietary individual survey carried out in Italy (INN-CA study). The daily intakes of total iron and heme iron were 1.65 and 1.13 mg/person/day. Zinc intake was 3.65 mg/person/day. Beef made the main contribution to iron, heme iron, and zinc daily intakes. Copper daily intake was 107.3 mug/person/day, with meat products provided the highest contribution (40 mug/person/day). Daily intake of selenium (7.14 mug/person/day) was provided mainly by poultry consumption. Thiamine intake was 228 mug/person/day, and meat products were the main source (110 mug/person/day). Riboflavin intake was 136 mug/person/day, with both beef and meat products as the main contributors (40 mug/person/day). Niacin intake was 7.53 mg/person/day, and poultry was the main source (2.28 mg/person/day). Meat and meat products were a valuable source of micronutrients, supplying 47, 48, and 24% of zinc, niacin, and thiamin daily requirements, respectively, and over 10% of iron, copper, selenium, and riboflavin daily average requirement values of the italian RDAs calculated for the population involved in the survey (INN-CA study).

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Effects of Retinoic Acid and 1,25-Dihydroxyvitamin D3 on IFN-gamma Secretion by Mononuclear Leukocytes from Nulliparous and Postparturient Dairy Cattle

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831.70.3.92 ◽

2000 ◽

Vol 70 (3) ◽

pp. 92-101 ◽

Cited By ~ 14

Author(s):

Burim Ametaj ◽

Brian Nonnecke ◽

Ronald Horst ◽

Donald Beitz

Keyword(s):

Retinoic Acid ◽

Dairy Cattle ◽

Dairy Cows ◽

Dairy Cow ◽

Pokeweed Mitogen ◽

Mononuclear Leukocytes ◽

Combined Effects ◽

Ifn Gamma ◽

Dihydroxyvitamin D ◽

1,25 Dihydroxyvitamin D

Individual and combined effects of several isomers of retinoic acid (RA) and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on interferon-gamma (IFN-gamma) secretion by blood mononuclear leukocytes (MNL) from nulliparous and postparturient Holstein cattle were evaluated in vitro. In the first experiment, effects on incubation period (24 to 72 hours) and time of supplementation (0 to 32 hours) with all-trans, 9-cis, 13-cis-, and 9,13-dicis-RAs (0 to 100 nM) on IFN-gamma secretion by pokeweed mitogen (PWM)-stimulated (0 and 10 mug/ml) MNL from nulliparous cattle were evaluated. In the second experiment, MNL from postparturient cows (bled at 0, 2, 4, and 16 days postpartum) were stimulated with PWM (0 and 10 mug/ml) in the presence of RA isomers (9-cis- or 9,13-dicis-RA; 0 to 100 nM), 1,25-(OH)2D3 (0 to 100 nM), or with combinations of these metabolites. The results show that individual isomers of RA had no effect on IFN-gamma secretion by PWM-stimulated MNL from nulliparous or postparturient cows. Furthermore 1,25-dihydroxyvitamin D3 inhibited IFN-gamma secretion by MNL from nulliparous and postparturient dairy cows; however, the degree of inhibition was greater when 9-cis- and 9,13-dicis-RA were also present in the cultures. Finally mononuclear leukocytes from postparturient dairy cows produced substantially less IFN-gamma than did MNL from nulliparous cattle. It is concluded that retinoic acids individually did not affect the capacity of leukocytes from dairy cattle to secrete IFN-gamma. This result is in marked contrast to studies in monogastric species indicating that RAs inhibit IFN-gamma secretion by peripheral blood T cells. Inhibition of IFN-gamma secretion by 1,25-(OH)2D3 was potentiated by 9-cis- and 9,13-di-cis-retinoics acids, suggesting that an excess of dietary vitamins A and D may compromise further the naturally immunosuppressed postparturient dairy cow. Additional research is necessary to determine if the combined effects of these metabolites on IFN-gamma secretion represent an increased susceptibility of the dairy cow to infectious diseases during the periparturient period. Lower secretion of IFN-gamma by MNL from postpartutient dairy cows, relative to nulliparous cattle, suggests that recently-calved cows are naturally immunosuppressed.

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