The aim of this study was to investigate the presence of heavy metals/metalloids (Pb, Cd, Hg, Cu, Fe, Zn, As) in the muscle tissue of fish from the Danube River (two locations: Zemun and Grocka). For ...the purpose of heavy metal determination in fish muscle, 120 samples of six different fish species, Prussian carp, barbel, bream, carp, pike perch, and catfish were collected. For determining heavy metals, we used microwave oven digestion and atomic absorption spectrometer methods. The highest average content of Pb (0.084 ± 0.004 mg kg
−1
), Cd (0.082 ± 0.003 mg kg
−1
), Hg (0.466 ± 0.006 mg kg
−1
), and As (0.333 ± 0.007 mg kg
−1
) was found in the muscle of carp (an omnivorous fish) from Grocka, while the highest average level of Fe (13.60 ± 0.03 mg kg
−1
) was deposited in bream (also omnivorous) from Zemun. Also, the average Cu level (1.62 ± 0.13 mg kg
−1
) was the highest in catfish muscle (a carnivorous fish) from Grocka, while the highest Zn content (11.16 ± 0.17 mg kg
−1
) was determined in muscle of Prussian carp (an omnivorous fish) from Zemun. The highest content of heavy metals (Cu, Fe, and Zn, respectively) in muscle of the six different types of fish from both locations was symmetrically arranged by species (catfish, barbel, and Prussian carp, respectively). Concentrations of Pb, Hg, and As in the Danube River fish muscle were under the maximum residual levels prescribed by the European Union (EU) and the maximum allowed concentrations (MAC) for Serbia. On the other hand, in all fish muscle from both locations (Zemun and Grocka), higher concentrations of Cd than prescribed (MAC) were found, with the exception of bream and pike perch.
This paper illustrates the potential of the FOTELP-VOX code, a modification
of the general-purpose FOTELP code, combining Monte Carlo techniques to
simulate particle transportation from an external ...source through the
internal organs, resulting in a 3-D absorbed dose distribution. The study
shows the comparison of results obtained by FOTELP software and the
volumetric modulated arc therapy technique. This planning technique with two
full arcs was applied, and the plan was created to destroy the diseased
tissue in the eye tumor bed and avoid damage to surrounding healthy tissue,
for one patient. The dose coverage, homogeneity index, conformity index of
the target, and the dose volumes of critical structures were calculated.
Good agreement of the results for absorbed dose in the human eye was
obtained using these two techniques.
Nickel manganite nanocrystalline fibers were obtained by electrospinning and subsequent calcination at 400 °C. As-spun fibers were characterized by TG/DTA, Scanning Electron Microscopy and FT-IR ...spectroscopy analysis. X-ray diffraction and FT-IR spectroscopy analysis confirmed the formation of nickel manganite with a cubic spinel structure, while N2 physisorption at 77 K enabled determination of the BET specific surface area as 25.3 m2/g and (BJH) mesopore volume as 21.5 m2/g. The material constant (B) of the nanocrystalline nickel manganite fibers applied by drop-casting on test interdigitated electrodes on alumina substrate, dried at room temperature, was determined as 4379 K in the 20–50 °C temperature range and a temperature sensitivity of −4.95%/K at room temperature (25 °C). The change of impedance with relative humidity was monitored at 25 and 50 °C for a relative humidity (RH) change of 40 to 90% in the 42 Hzπ1 MHz frequency range. At 100 Hz and 25 °C, the sensitivity of 327.36 ± 80.12 kΩ/%RH was determined, showing that nickel manganite obtained by electrospinning has potential as a multifunctional material for combined humidity and temperature sensing.
Nanocrystalline iron manganite powder was synthesized using the sol-gel combustion process, with glycine as fuel. It was further calcined at 900 °C for 8 h, resulting in the formation of a loose ...cubic FeMnO
powder with a small specific surface area, net-like structure and plate-like particles as confirmed by XRD, N
physisorption, FESEM and TEM analyses. The metal ion release was studied by ICP-OES and showed that less than 10 ppb of Fe or Mn ions were released by leaching in water, but 0.36 ppm Fe and 3.69 ppm Mn was found in LB (Luria-Bertani) bacterial medium. The generation of reactive oxygen species (ROS) was monitored in distilled water and bacterial medium and showed that FeMnO
particles do not generate O
˙
ions with or without UV irradiation, but synthesize H
O
and show an antioxidative effect. Besides the higher stability of FeMnO
particles in aqueous solution they showed an inhibitory effect on
growth in LB medium even at low concentrations (0.01 mg ml
), but not in BHI medium even at 1 mg ml
. This study points out that the mechanism of antibacterial action of engineered metal oxides needs continued investigation and specific experimental controls.
Here, we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsychotic drug trifluoperazine (TFP). The sensor was built using inkjet-printed ...carbon nanotube (CNT) electrodes, which were modified with dimercaptosuccinic acid (DMSA)-coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron microscopy techniques (transmission electron microscopy (TEM) and field emission-scanning electron microscopy (FE-SEM)), X-ray powder diffraction, ζ-potential measurements, dynamic light scattering (DLS), and electrochemical methods (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)). The developed sensor, best operated at pH 7 in the Britton–Robinson buffer solution (BRBS), shows linear electrocatalytic activity with TFP in the concentration range of 1–50 μM, a low detection limit of 0.54 μM, and excellent selectivity, repeatability, and reproducibility with an relative standard deviation (RSD) of 2.4%. A voltammetric approach using square wave voltammetry (SWV) is a sensitive technique under optimized conditions for the analytical determination of submicromolar amounts of TFP. Bare CNT and RGO- and DMSA/Fe3O4-modified CNT electrodes showed lower electrocatalytic activity than the DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticle-decorated graphene nanosheets can offer a tool for point-of-care applications as sensors in biomedicine.
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•Iron manganite thick films on test interdigitated PdAg electrodes as humidity sensor.•Mercury porosimetry measured on thick film samples.•Fast response and recovery, low hysteresis.
...Iron manganite (FeMnO3) powder with a cubic (bixbyite, Ia3-) crystal structure was obtained by a solid state reaction. Thick film paste (powder + organic vehicles) was screen printed on alumina substrate with test interdigitated PdAg electrodes. Significant porosity (60.6%) composed of macropores (larger than 100 nm) was determined by Hg porosimetry, changing only slightly from the first extrusion run indicating a stable pore system. Hg porosimetry evaluation of thick film samples enabled estimation of true textural parameters of the thick film compared to powder. Impedance response of the thick film sensor was monitored in a humidity chamber in the relative humidity (RH) range 30–90%, at room temperature (25 °C) and frequency range from 42 Hz to 1 MHz. At 100 Hz the impedance reduced from 10.41 MΩ for RH 30% to 0.68 MΩ for RH 90%. Analysis of complex impedance using an equivalent circuit showed the dominant influence of grain boundaries. The sensor response and recovery was fast (several seconds) and a relatively low hysteresis value of 2.8% was obtained.
Boron neutron capture therapy is based on neutron capture by 10B and creation
of high energy alpha particle and recoiled 7Li ion which have ranges
comparable to cell dimensions. The MCNP5/X code is ...applied for calculation
of the absorbed doses as well as dose distribution by depth in pancreas
cancer and the organs of the analytical and voxelized Oak Ridge National
Laboratory phantom, which represents the human body. The depth dose
distributions for thermal, epithermal neutrons, and neutron spectrum, show
that the absorbed doses are the largest exactly in the cancer, in all cases.
It is found by this simulation that the epithermal neutrons are the
optimal choice for BNC therapy. They deliver a similar dose to cancer as the
thermal neutrons but, spare the healthy tissue more than the thermal ones.
Two new nitrato complexes of zinc and nickel with 1,4,8,11-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), have been synthesized and characterized. The IR spectral peaks showed ...that the coordinated and ionic nitrate ions are in agreement with the formula proposed by elemental analysis. Conductometric titrations predicted methanol to be a convenient solvent for synthesis and revealed the stoichiometry of the complexes, while molar electrical conductivities indicated a 1 : 3 complex electrolyte type for the zinc complex, and a 1 : 2 complex electrolyte type for the nickel complex. The optimized complex structure was obtained by molecular modeling and density functional theory calculations. The biological activity of the novel complexes was examined by screening eight different bacterial strains and two cancer cell lines. The zinc complex showed better antimicrobial activity against the bacterial strains, while the complexes did not show significance antiproliferative activity toward cancer cells MCF-7 and MDA-MB-231.
The aim of this study was to determine the influence of different feed composition and cultivation on the composition of fatty acids, their relationships, and the cholesterol content in the tissue of ...rainbow trout (Oncorhynchus mykiss). Trout were reared in ponds at two different altitudes and raised on different feeds. The total amount of monounsaturated fatty acids in fillets of both groups showed no statistically significant difference. However, higher levels of n‐6 fatty acids were found in Pond I trout fillets than in Pond II fillets, while Pond II fillets contained almost even amounts of n‐3 and n‐6 fatty acids. Total cholesterol content in Pond I trout fillets was significantly lower (p < 0.05) than in Pond II fillets. The results indicate that the final composition of the trout fillets was mostly dependent on the feed the live fish had consumed; the altitude of the ponds had less effect. Also, both groups of trout could be used in the human diet as biologically valuable foods.
Practical application: Our results show influence of altitude, feed, and fatty acid composition of feed on trout fillets. The average fatty acid level in the trout fillets increased in the order SFA <MUFA <PUFA. Trout fillets contain low levels of cholesterol but high levels of EPA, DPA, and DHA. These facts are important for fish industries and aquaculture producers to design a healthy food.
The trout, although grown at two different altitudes, showed differences in their basic chemical composition and in their fatty acid composition which more tended to be related to the composition of their feed. Low cholesterol levels and high levels of EPA, DPA, and DHA, as well as reasonably favorable ratios of n‐3 and n‐6 fatty acids indicate that the trout from both groups could be suitable for use in the human diet as biologically valuable foods.
The trout, although grown at two different altitudes, showed differences in their basic chemical composition and in their fatty acid composition which more tended to be related to the composition of their feed. Low cholesterol levels and high levels of EPA, DPA, and DHA, as well as reasonably favorable ratios of n‐3 and n‐6 fatty acids indicate that the trout from both groups could be suitable for use in the human diet as biologically valuable foods.
The purpose of the present study was to investigate and compare the effects of two ruthenium complexes with trifluoperazine on acethylcholinesterase enzyme activity and lactate dehydrogenase levels ...in vivo under physiological conditions in rats blood. Complexes 1 and 2 showed positive effects on acethylcholinesterase at all doses and did not disturb its normal activity. Total LDH activity was inhibited in the presence of both complexes, but Ru(II) complexes showed different effects on the activity of LDH isoenzymes. The activities of LDH
and LDH
isoenzymes were decreased in all applied doses of the complex 2, while the activity of LDH
reduced using complex 1 in the same doses. Results of the present study suggest the neuro- and cardio protective potential of oral administration of complexes 1 and 2, as non-toxic compounds under physiological conditions. These protective effects are the result of their potent antioxidant activity.
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