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Number of results: 9
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Abstract

The aim of this study was to verify the hypothesis postulating that the supplementation of turkey diets with Cu nanoparticles can lower dietary inclusion levels of Cu without compromising the growth rate and antioxidant status of turkeys. The experiment was carried out on 648 one-day-old Hybrid Converter turkeys divided into 6 groups with 6 replicates per group, in a two-factorial design with 3 dietary inclusion levels of Cu (20, 10 and 2 mg/kg) and 2 dietary sources of Cu - copper sulfate (Cu-SUL) and Cu nanoparticles (Cu-NP). At 42 days of age, blood samples were collected from 2 birds per replicate (12 birds per group), after slaughter livers were collected for analyses. Blood and liver samples were assayed for: Cu, Zn, Ca, P, Mg, GLU, TP, ALB, UREA, TAG, TC, UA, ALT, AST, ALT, GGT, ALP, SOD, GPx, CAT, VIT C, FRAP, GSH+GSSG, LOOH, MDA. The results of this experiment demonstrate that a decrease in the dietary inclusion levels of Cu from 10 mg/kg to 2 mg/kg does not compromise the growth performance of turkeys, but weakens antioxidant defense mechanisms. A Cu dose of 20 mg/kg induces oxidation reactions and has a much more inhibitory effect on the antioxidant defense system than dietary Cu content of 2 mg/kg. In turkeys, dietary supplementation with Cu-NP has a more beneficial effect on carbohydrate metabolism and antioxidant status compared with Cu-SUL. The results of analyses examining the antioxidant and metabolic status of young turkeys indicate that 10 mg/kg is the optimal dietary inclusion level of Cu.
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Authors and Affiliations

K. Kozłowski
J. Jankowski
K. Otowski
Z. Zduńczyk
K. Ognik
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Abstract

In this work, the spectrophotometric studies on the kinetics of redox reaction between gold(III) bromide complexes and sodium nitrite, were carried out. From the kinetic curves collected under different conditions of reactants concentration, addition of bromide ions, temperature, pH and ionic strength, corresponding rate constants have been determined. The obtained results suggest the complex path of the [AuBr4]– reduction consisting of two parallel, bimolecular reactions where different reductant species (HNO2 and NO2–) take place and consecutive step with the metallic gold production. The second-order rate constants at 20oC are equal to 2.948 and 0.191 M–1·s–1, respectively. The values of activation enthalpy and activation entropy for the first and the second parallel step of the reaction were found to be ΔH‡ = 29.18 kJ·mol–1 and ΔS‡ = –13.95 J·mol–1·K, and ΔH‡ = 40.75 kJ·mol–1 and ΔS‡ = –31.06 ­J·mol–1·K, respectively. It was found that the reaction accelerates significantly with the increase of pH and is inhibited with the increase of Br– concentration. The substitutive, inner-sphere mechanism of electron transfer in the studied system was also suggested.

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Authors and Affiliations

K. Pacławski
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Abstract

Marine sediments with rapid oxic/anoxic transitions are difficult to monitor in real time. Organic overload that may lead to anoxia and buildup of hydrogen sulfide can be caused by a variety of factors such as sewage spills, harbor water stagnation, algal blooms and the vicinity of aquaculture operations. We have tested a novel multiprobe technology (named SPEAR) on marine sediments to evaluate its performance in monitoring sediments and overlaying water. Our results show the ability of the SPEAR probes to distinguish electrochemical changes at 2-3 mm scale and at hourly cycles. SPEAR probes have the ability to identify redox interfaces and redox transition zones in sediments, but do not use micromanipulators (which are cumbersome in field and underwater applications). We propose that the best target habitats for SPEAR-type monitoring are rapidly evolving muddy deposits and sediments near aquaculture operations where pollution with organics stresses the ecosystem.
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Authors and Affiliations

R. Popa
1
ORCID: ORCID
I.C. Moga
1
ORCID: ORCID
K.H. Nealson
2
ORCID: ORCID
V.M. Cimpoiasu
3
ORCID: ORCID

  1. DFR Systems SRL, R&D Department, Bucharest, Romania
  2. University of Southern California, Los Angeles, 90089, USA
  3. University of Craiova, Biology and Environmental Engineering Department, Frontier Biology and Astrobiology Research Center, Craiova, 200585, Romania
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Abstract

The objective of the study was to determine the possibility of using organic soil under willow for wastewater purification of excess nitrate and phosphates, and to estimate the applicability of redox potential for the assessment oftransformation ofnitrogen compounds in the soil under study. The study showed the suitability of organic soil and willow for wastewater purification under the conditions of the ,,Hajdów" experimental object. Also, significant relationships were shown between redox potential and nitrogen transformation occurring in soil irrigated with wastewater after 2nd stage of treatment.
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Authors and Affiliations

Urszula Kotowska
Teresa Włodarczyk
Małgorzata Brzezińska
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Abstract

The most common means to analyze redox gradients in sediments is by push/pulling electrochemical probes through sediment’ strata while repeating measurements. Yet, as electrodes move up and down they disrupt the texture of the sediment layers thus biasing subsequent measurements. This makes it difficult to obtain reproducible measurements or to study the evolution of electrochemical gradients. One solution for solving this problem is to eliminate actuators and electrode movements altogether, while instead deploying probes with numerous electrodes positioned at various depths in the sediment. This mode of operation requires electrode switching. We discuss an electrode-switching solution for multi-electrode probes, based on Complementary Metal-Oxide-Semiconductor (CMOS) multiplexors. In this solution, electrodes can be individually activated in any order, sequence or time frame through digital software commands. We discuss constraints of CMOS-based multilayer electrochemical probes during cyclic voltammetry.
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Authors and Affiliations

V.M. Cimpoiasu
1
ORCID: ORCID
F. Radulescu
2
K.H. Nealson
3
ORCID: ORCID
I.C. Moga
4
ORCID: ORCID
R. Popa
4
ORCID: ORCID

  1. University of Craiova, Frontier Biology and Astrobiology Research Center, Biology and Environmental Engineering Department, Craiova, 200585, Romania
  2. Portland, OR, 97229
  3. University of Southern California, Department of Biological Sciences, 3616, Trousdale Parkway, Los Angeles, 90089, USA
  4. DFR Systems SRL, R&D Department, Bucharest, Romania
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Abstract

The use of lactoferrin (LF) and/or lactobacillus sp. (LB) to improve animal health and production has increased recently. However, information regarding the immune-modulatory role of LB supplementations either alone or in combination with LF in sheep remains unclear. Therefore, the present study was designed to evaluate the immune modulating properties and the antioxidant activity of supplementing commercially available LF and/or LB in healthy lambs. For this reason, twenty-four apparently healthy Ossimi lambs were used. After three weeks of acclimatization, the lambs were randomly allocated to four equal-sized groups and assigned to receive one of the following supplements: LB at a dose of ~ 1 g active ingredient/head (group 1), LF at a dose rate of 0.5 gm /head (group 2), a combination of both treatments using the same dosing regimens (group 3), and (group 4) received only 10 mL of isotonic saline and was considered as a control group. All supplements were given orally twice daily for 30 consecutive days. Blood samples were collected from each lamb before starting the experiment (T0) and two weeks (T15), and four weeks (T30) after giving supplements for hematological examinations, serum biochemical analyses, and RT-PCR assays. Our findings demonstrated that lambs receiving LB showed statistically significant (P<0.05) higher values of total leucocytes, lymphocytes and lysozyme activity than those receiving LF. In contrast, lambs that received LF had significantly (P< 0.05) higher values of serum catalase, nitric oxide and GSH with a significantly lower MDA level compared with those supplemented with LB. A combination of LF and LB supplementation elicited maximal up-regulation of Tollip, TLR4, IL-5, and IL-6 gene expression compared with other groups. The results suggest that bovine LF and or LB could be used as useful nutritional supplements to support the immune system in healthy lambs.

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Authors and Affiliations

M. El-Ashker
E. Risha
F. Abdelhamid
A. Ateya
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Abstract

The current task explores automatic generation control knowledge under old-style circumstances for a triple-arena scheme. Sources in area-1 are thermal-solar thermal (ST); thermalgeothermal power plant (GPP) in area-2 and thermal-hydro in area-3. An original endeavour has been set out to execute a new performance index named hybrid peak area integral squared error (HPA-ISE) and two-stage controller with amalgamation of proportional-integral and fractional order proportional-derivative, hence named as PI(FOPD). The performance of PI(FOPD) has been compared with varied controllers like proportional-integral (PI), proportional-integralderivative (PID). Various investigation express excellency of PI(FOPD) controller over other controller from outlook regarding lessened level of peak anomalies and time duration for settling. Thus, PI(FOPD) controller’s excellent performance is stated when comparison is undergone for a three-area basic thermal system. The above said controller’s gains and related parameters are developed by the aid of Artificial Rabbit Optimization (ARO). Also, studies with HPA-ISE enhances system dynamics over ISE. Moreover, a study on various area capacity ratios (ACR) suggests that high ACR shows better dynamics. The basic thermal system is united with renewable sources ST in area-1 also GPP in area-2. Also, hydro unit is installed in area-3. The performance of this new combination of system is compared with the basic thermal system using PI(FOPD) controller. It is detected that dynamic presentation of new system is improved. Action in existence of redox flow battery is also examined which provides with noteworthy outcome. PI(FOPD) parameters values at nominal condition are appropriate for higher value of disturbance without need for optimization.
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Authors and Affiliations

Arindita Saha
1
Tirumalasetty Chiranjeevi
2
Ramesh Devarapalli
3
ORCID: ORCID
Naladi Ram Babu
4
Puja Dash
5
Fausto Pedro Garcìa Màrquez
6

  1. Department of Electrical Engineering, RegentEducation & Research Foundation Group of Institutions, Kolkata, West Bengal, India
  2. Department of ElectricalEngineering, Rajkiya Engineering College Sonbhadra, U.P., India
  3. Institute of Chemical Technology, IndianOil Odisha Campus, Bhubaneswar, India
  4. Department of Electrical & Electronics Engineering,Aditya Engineering College, Surampalem, Andhra Pradesh, India
  5. Department of Electrical and Electronics Engineering,Gayatri Vidya Parishad College of Engineering (Autonomous), Visakhapatnam, Andhra Pradesh,India
  6. Ingenium ResearchGroup, University of Castilla-La Mancha, Spain
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Abstract

Electricity storage is one of the best-known methods of balancing the energy supply and demand at a given moment. The article presents an innovative solution for the construction of an electric energy storage device obtained from an innovative photovoltaic panel made of new dye-based photovoltaic modules and newly developed supercapacitors – which can be used as an emergency power source. In the paper, for the first time, we focused on the successful paring of new dye-sensitized solar cell (DSSC) with novel supercapacitors. In the first step, a microprocessor stand was constructed using Artificial Intelligence algorithms to control the parameters of the environment, as well as the solar charger composed of six DSSC cells with the dimensions of 100_100 mm and 126 CR2032 coin cells with a total capacitance of 60 F containing redox-active aqueous electrolyte. It was proven that the solar charger store enough energy to power, i.e. SOS transmitter or igniters, using a 5 V signal.
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Authors and Affiliations

Ireneusz Plebankiewicz
1
ORCID: ORCID
Krzysztof. A. Bogdanowicz
1
ORCID: ORCID
Paweł Kwaśnicki
2 3
Magdalena Skunik-Nuckowska
4
Patryk M. Rączka
3
Paweł Kulesza
4
Agnieszka Iwan
1
ORCID: ORCID
Wojciech Przybył
1

  1. Military Institute of Engineer Technology, ul. Obornicka 136, 50-961 Wrocław, Poland
  2. Research & Development Centre for Photovoltaics, ML System S.A. Zaczernie 190G, 36-062 Zaczernie, Poland
  3. Department of Physical Chemistry and Physicochemical Basis of Environmental Engineering, Institute of Environmental Engineering in Stalowa Wola, John Paul II Catholic University of Lublin, ul. Ofiar Katynia 6, 37-450 Stalowa Wola Poland
  4. Faculty of Chemistry, Warsaw University, ul. Pasteura 1, 02-093 Warsaw, Poland
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Abstract

The nature of the Cenomanian–Turonian Oceanic Anoxic Event (CTOAE) and its δ13 C Excursion is considered in the light of (1) the stratigraphical framework in which the CTOAE developed in the European shelf seas, (2) conclusions that can be drawn from new detailed investigations of the Chalk succession at three locations in England, at Melton Ross and Flixton in the Northern Province where organic-rich ‘black bands’ are present, and at Dover in the Southern Province (part of the Anglo-Paris Basin) where they are absent, and (3) how these conclusion fit in with the present understanding of the CTOAE. The application of the cerium anomaly method (German and Elderfield 1990) at Dover, Melton Ross and Flixton has allowed the varying palaeoredox conditions in the Chalk Sea and its sediments to be related to the acid insoluble residues, organic carbon, δ18O (calcite), δ13C (calcite), δ13C (organic matter), Fe 2+ and Mn2+ (calcite), and P/TiO2 (acid insoluble residue). This has provided evidence that the initial stages of the δ13C Excursion in England were related to (1) a drop of sea level estimated at between 45 and 85 metres, (2) influxes of terrestrial silicate and organic detritus from adjacent continental sources and the reworking of exposed marine sediments, and (3) the presence of three cold water phases (named the Wood, Jefferies and Black) associated with the appearance of the cold-water pulse fauna during the Plenus Cold Event. Conditions in the water column and in the chalk sediment were different in the two areas. In the Northern Province, cerium-enriched waters and anoxic conditions were widespread; the δ13C pattern reflects the interplay between the development of anoxia in the water column and the preservation of terrestrial and marine organic matter in the black bands; here the CTOAE was short-lived (~0.25 Ma) lasting only the length of the Upper Cenomanian Metoicoceras geslinianum Zone. In the Southern Province, water conditions were oxic and the δ13C Excursion lasted to the top of the Lower Turonian Watinoceras devonense Zone, much longer (~1.05 Ma) than in the Northern Province. These differences are discussed with respect to (1) the Cenomanian–Turonian Anoxic Event (CTAE) hypothesis when the ocean-continent-atmosphere systems were linked, (2) limitations of chemostratigraphic global correlation, and (3) the Cenomanian–Turonian Anoxic Event Recovery (CTOAER), a new term to define the varying lengths of time it took different oceans and seas to recover once the linked ocean-continent-atmosphere system was over. The possibility is considered that glacio- eustasy (the glacial control hypothesis of Jeans et al. 1991) with the waxing and waning of polar ice sheets, in association with the degassing of large igneous provinces, may have set the scene for the development of the Cenomanian–Turonian Anoxic Event (CTAE).
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Authors and Affiliations

Christophers V. Jeans
1
David S. Wray
2
C. Terry Williams
3
David J. Bland
4
Christopher J. Wood
5

  1. Department of Earth Sciences, University of Cambridge, Downing Place, Cambridge, CB2 3EN, UK
  2. School of Science, University of Greenwich, Pembroke, Chatham Maritime, Kent, ME4 4TB, UK
  3. Department of Mineralogy, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
  4. 15 Pains Close, Pinner, Middlesex, HA5 3BN, UK
  5. Deceased

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