Highly Ordered Macroporous Poly-3,4-ortho-xylendioxythiophene Electrodes as a Sensitive Analytical Tool for Heavy Metal Quantification

Presence of hazardous minerals in three major components (soil, forage and buffalo serum) was evaluated for determining extent of metal contamination in Sargodha, Pakistan. Ten soil and forage samples for each season were taken from ten randomly selected sites. 30 grazing buffaloes of �niliravi� breed (calves, non-lactating and lactating) were also sampled randomly from these sites for collection of serum. Heavy metal quantification via atomic absorption spectrophotometry was carried out for selenium, molybdenum and arsenic. Non-significant but positive correlation was found for selenium (Se) concentrations in soil, forage and serum and molybdenum (Mo) concentrations in soil and serum. Negative correlation (p]0.05) was obtained for Mo level between forage-serum and soil-forage which was indicative of molybdenum deficiency in the soil. The results suggested that the heavy metals remained below maximum permissible levels and were non-toxic for the ruminants of the study area.

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A critical review on integrating multiple fish biomarkers as indicator of heavy metals contamination in aquatic ecosystem

International Journal of Bioassays ◽

10.21746/ijbio.2017.9.5 ◽

2017 ◽

Vol 6 (9) ◽

pp. 5494 ◽

Cited By ~ 1

Author(s):

Vijay Hemmadi

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Superoxide Dismutase ◽

Critical Review ◽

High Concentration ◽

Heavy Metals Contamination ◽

Metal Quantification ◽

Fish Biomarkers ◽

Selection Of ◽

Detection And Quantification

An immense amount of data is available on biomarkers related to different eco-toxicants. But data on contaminant-specific biomarkers in fishes is sparse. Traditionally, detection and quantification of heavy metals in sediment, water, and biota gave us valuable information on the quantity and the type of heavy metal present in the ecosystem. This information can be utilized to select a heavy metal specific biomarker. For an instance, if Cadmium (Cd), Zinc (Zn) and Cupper (Cu) are at high concentration, then Metallothionein (MT) can be a good candidate biomarker. Along with this, Superoxide dismutase (SOD) is a very potent indicator of Iron (Fe) and Mercury (Hg) contamination and also Catalase (CAT) is specific for Cadmium (Cd) and Zinc (Zn) exposure. For these kinds of selection of biomarker, the researchers should know heavy metals type specific biomarker. This review is the small effort towards cumulating the heavy metals type specific biomarker. This demonstrates the exposure and effects of heavy metals in fishes by integrating the heavy metal quantification and biomarker selection.

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LPCD framework: Analytical tool or psychological model?

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001383 ◽

2018 ◽

Vol 41 ◽

Author(s):

David Danks

Keyword(s):

Decision Making ◽

Analytical Tool ◽

Mathematical Framework ◽

Bayesian Decision ◽

Perceptual Decision Making ◽

Psychological Model ◽

Psychological Reality ◽

Psychological Theories ◽

Target Article ◽

Bayesian Decision Making

AbstractThe target article uses a mathematical framework derived from Bayesian decision making to demonstrate suboptimal decision making but then attributes psychological reality to the framework components. Rahnev & Denison's (R&D) positive proposal thus risks ignoring plausible psychological theories that could implement complex perceptual decision making. We must be careful not to slide from success with an analytical tool to the reality of the tool components.

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Complementary Z-Contrast Imaging and Digital Image Processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118394 ◽

1985 ◽

Vol 43 ◽

pp. 304-305

Author(s):

K. N. Colonna ◽

G. Oliphant

Keyword(s):

Image Processing ◽

Heavy Metal ◽

Digital Image Processing ◽

Digital Image ◽

Biological Tissue ◽

Biological Imaging ◽

Tissue Preparation ◽

Contrast Imaging ◽

Imaging Tool ◽

Z Contrast

Harmonious use of Z-contrast imaging and digital image processing as an analytical imaging tool was developed and demonstrated in studying the elemental constitution of human and maturing rabbit spermatozoa. Due to its analog origin (Fig. 1), the Z-contrast image offers information unique to the science of biological imaging. Despite the information and distinct advantages it offers, the potential of Z-contrast imaging is extremely limited without the application of techniques of digital image processing. For the first time in biological imaging, this study demonstrates the tremendous potential involved in the complementary use of Z-contrast imaging and digital image processing.Imaging in the Z-contrast mode is powerful for three distinct reasons, the first of which involves tissue preparation. It affords biologists the opportunity to visualize biological tissue without the use of heavy metal fixatives and stains. For years biologists have used heavy metal components to compensate for the limited electron scattering properties of biological tissue.

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Recent Progress In High-Resolution Shadowing For Biological Transmission Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100181300 ◽

1990 ◽

Vol 48 (1) ◽

pp. 510-511 ◽

Cited By ~ 1

Author(s):

Heinz Gross ◽

Katarina Krusche ◽

Peter Tittmann

Keyword(s):

Heavy Metal ◽

High Resolution ◽

Freeze Drying ◽

Atmospheric Conditions ◽

Vacuum Equipment ◽

Transmission Electron ◽

Gas Atmosphere ◽

Gas Molecules ◽

Residual Gas ◽

Backing Layer

Freeze-drying followed by heavy metal shadowing is a long established and straight forward approach to routinely study the structure of dehydrated macromolecules. Very thin specimens such as isolated membranes or single macromolecules are directly adsorbed on C-coated grids. After rapid freezing the grids are transferred into a suitable vacuum equipment for freeze-drying and heavy metal shadowing.To improve the resolution power of shadowing films we introduced shadowing at very low specimen temperature (−250°C). To routinely do that without the danger of contamination we developed in collaboration with Balzers an UHV (p≤10-9 mbar) machine (BAF500K, Fig.2). It should be mentioned here that at −250°C the specimen surface acts as effective cryopump for practically all impinging residual gas molecules from the residual gas atmosphere.Common high resolution shadowing films (Pt/C, Ta/W) have to be protected from alterations due to air contact by a relatively thick C-backing layer, when transferred via atmospheric conditions into the TEM. Such an additional C-coat contributes disturbingly to the contrast at high resolution.

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