67 research outputs found
A novel dopamine electrochemical sensor based on La3+/ZnO nanoflower modified graphite screen printed electrode
Flower-like La3+/ZnO nanocomposite was facile synthesized. A simple and ultrasensitive sensor based on graphite screen printed electrode (SPE) modified by La3+/ZnO nanoflower was developed for the electrochemical determination of dopamine. The electrochemical behavior of dopamine was studied in 0.1 M phosphate buffer solution (PBS) using cyclic voltammetry (CV), chronoamperometry (CA) and differential pulse voltammetry (DPV). Compared with the unmodified graphite screen printed electrode, the modified electrode facilitates the electron transfer of dopamine, since it notably increases the oxidation peak current of dopamine. Also, according to CV results the maximum oxidation of dopamine on La3+/ZnO/SPE occurs at 150 mV which is about 140 mV more negative compared with unmodified SPE. Under optimized conditions, the modified electrode exhibited a linear response over the concentration range from 0.15 to 300.0 μM, with a detection limit of 0.08 μM (S/N = 3). The proposed sensor exhibited a high sensitivity, good stability and was successfully applied for dopamine determination in dopamine ampoule, with high recovery
An Intelligent technical analysis using neural network
Technical analysis has been one of the most popular methods for stock market predictions for the past few decades. There have been enormous technical analysis methods to study the behavior of stock market for different kinds of trading markets such as currency, commodity or stock. In this paper, we propose two different methods based on volume adjusted moving average and ease of movement for stock trading. These methods are used with and without generalized regression neural network methods and the results are compared with each other. The preliminary results on historical stock price of 20 firms indicate that there is no meaningful difference between various proposed models of this paper
A sensitive Cu(salophen) modified screen-printed electrode for simultaneous determination of dopamine and uric acid
This research applied a nanostructured electrochemical sensor with a screen-printed electrode (SPE) for examining the dopamine (DA) electrocatalytic oxidation when uric acid (UA) was present. Cu(salophen) nanostructured modified SPE (Cu(salophen)/SPE)was employed to investigate the electrochemical behavior of DA. At optimal pH (pH7.0), oxidation of DA at the modified electrode takes place at a potential around 100 mV less positive than at the unmodified SPE. Chronoamperometry was used to determine the diffusion coefficient of DA (D=1.96×10-5cm2s-1). Differential pulse voltammetry (DPV) showed linear response in the range between 0.2-450.0 μM for DA. The limit of detection (LOD) of DA was computed to be 0.05 μM. Moreover, Cu(salophen)/SPE was employed for determining DA in the presence of UA using DPV. The DPV results showed that at the modified electrode, two well-separated oxidation peaks of DA and UA could be obtained at potentials of 180 and 325 mV, respectively. This separation forms the basis for the co-detection of these two materials on the surface of Cu(salophen)/SPE. This sensor was then employed to determine DA and UA in real specimens
Glutathione detection at carbon paste electrode modified with ethyl 2-(4-ferrocenyl-[1,2,3]triazol-1-yl)acetate, ZnFe2O4nano-particles and ionic liquid
The purpose of the present study was to introduce a newly designed approach for deter-mination of glutathione using modified carbon paste electrode with ZnFe2O4nanoparticles, ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) and ethyl-2-(4-ferrocenyl--[1,2,3]triazol-1-yl)acetate (EFTA/ZFO/IL/CPE). According to the results from the electro-chemical experiments, oxidation current of glutathione on the modified electrode surface was incremented and its oxidation potential was decreased compared to bare CPE. A linear response was observed for the electrode at different glutathioneconcentrations (0.2 to 300.0 μM)
Utjecaj stresa pri prijevozu na kortizol, hormone štitnjače i neke biokemijske pokazatelje u serumu iranske kašmirske (Raini) koze.
In this study the effect of transportation stress on serum concentrations of cortisol, thyroid hormones, β-hydroxybutyrate, nonesterified fatty acids, glucose and plasma total protein in Iranian cashmere (Raini) goats were evaluated. On the first day, blood samples from 10 Raini goats (5 males and 5 non-lactating nonpregnant females) were collected at 8 A.M. (T1), and after 3h food and water deprivation (T2). On the second day, samples were collected at 8 A.M. (T3), and after 3h transport (T4). Final blood sample was taken 24 h after transport ended (T5). Food and water deprivation caused a significant decrement in serum cortisol, and a significant increase between T2 and T3 was evident. Transportation caused a significant increase in serum cortisol, and the increase continued until T5. Serum T3 showed a marginally significant decrease due to the food and water deprivation. Serum T4 and NEFA significantly increased between T2 and T3. No significant change in serum concentrations of glucose, fT3, fT4, T3/T4 ratio and BHBA in different samplings was observed. The current study showed that short road transport had a significant effect on some stress biomarkers in cashmere goats, however, it takes a longer time before hormonal control of metabolism can be affected.U iranskih kašmirskih (Raini) koza istražen je učinak stresa pri prijevozu na koncentraciju kortizola u serumu, hormone štitnjače, β-hidroksibutirat, neesterificirane masne kiseline, glukozu i ukupne bjelančevine plazme. Prvi dan, u 8,00 sati (T1), uzeti su uzorci krvi od 10 Raini koza (5 mužjaka i 5 ženki koje nisu bile u laktaciji ni gravidne). Uzorci krvi ponovno su uzeti tri sata (T2) nakon što je kozama bila uskraćena hrana i voda. Drugog dana uzorci su prikupljeni u 8,00 sati (T3), te nakon 3 sata prijevoza (T4). Konačni uzorak krvi uzet je 24 sata nakon što je prijevoz završio (T5). Kortizol u serumu nakon uskraćivanja hrane i vode bio je značajno snižen, a između T2 i T3 značajno povišen. Prijevoz je uzrokovao značajan porast kortizola u serumu što je nastavljeno do T5. T3 u serumu je pokazao granično značajan pad zbog uskraćivanja hrane i vode. T4 i NEFA u serumu bili su značajno povećani između T2 i T3. U različitim uzorcima nisu utvrđene značajne promjene u serumskim koncentracijama glukoze, fT3, fT4, omjeru T3/T4 i BHBA. Istraživanje je pokazalo da kratki cestovni prijevoz ima značajan učinak na neke biomarkere stresa u kašmirskih koza, međutim, za utjecaj na hormonsku kontrolu metabolizma potrebno je duže vremensko razdoblje
The Relationship Between Post-Traumatic Stress Disorder After Childbirth and Social Support and Marital Satisfaction
Background: Childbirth is among the most significant and pleasant events in a woman’s life. This event can be a traumatic event and a threat to the mother’s mental health. This study recognizes the relationship between Post-Traumatic Stress Disorder (PTSD) after childbirth and social support and marital satisfaction.Methods: This Cross-sectional analytical study was performed on a sample of 400 mothers who had delivered at Shohadaye-15-Khordad Hospital in Varamin (in two groups with & without PTSD). The research instruments include the Demographic, Midwifery, Neonatal Factors checklist, Enrich Marital Satisfaction, Weinfeld and Tigman Social Support, and the PTSD Symptoms Scale. We used SPSS to analyze the descriptive and Pearson correlation and logistic regression data. A P<0.05 was considered significant.Results: The prevalence of PTDS in this study was equal to 16.8%. There was no significant correlation between the mean of the total score of PTSD in all dimensions with social support (P>0.05). Marital satisfaction significantly affected the probability of PTSD after childbirth (P=0.001). There was a significant correlation between PTSD total score and dimension of avoidance symptoms and infant gender (P=0.038). There was also a significant correlation between gestational age and avoidance symptoms (P=0.001) and type of nutrition feeding and motivational symptoms (P=0.041) of PTSD dimensions.Conclusion: According to the relationship between marital satisfaction and PTSD, it is recommended to design suitable interventions to improve the marital status and promptly diagnose the susceptible mothers to prevent the spread of this complication
Quantum Bohmian-inspired potential to model non–Gaussian time series and Its application in financial markets
We have implemented quantum modeling mainly based on Bohmian mechanics to study time series that contain strong coupling between their events. Compared to time series with normal densities, such time series are associated with rare events. Hence, employing Gaussian statistics drastically underestimates the occurrence of their rare events. The central objective of this study was to investigate the effects of rare events in the probability densities of time series from the point of view of quantum measurements. For this purpose, we first model the non-Gaussian behavior of time series using the multifractal random walk (MRW) approach. Then, we examine the role of the key parameter of MRW, λ, which controls the degree of non-Gaussianity, in quantum potentials derived for time series. Our Bohmian quantum analysis shows that the derived potential takes some negative values in high frequencies (its mean values), then substantially increases, and the value drops again for rare events. Thus, rare events can generate a potential barrier in the high-frequency region of the quantum potential, and the effect of such a barrier becomes prominent when the system transverses it. Finally, as an example of applying the quantum potential beyond the microscopic world, we compute quantum potentials for the S&P financial market time series to verify the presence of rare events in the non-Gaussian densities and demonstrate deviation from the Gaussian case
Application of Fe3O4@SiO2/GO nanocomposite for sensitive and selective electrochemical sensing of tryptophan
A simple strategy for determination of tryptophan (TRP) based on Fe3O4@SiO2/GO nanocomposite modified graphite screen printed electrode (Fe3O4@SiO2/GO/SPE) is reported. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to characterize the performance of the sensor. The Fe3O4@SiO2/GO/SPE displayed excellent electrochemical catalytic activities. The oxidation overpotentials of tryptophan decreased significantly and its oxidation peak current increased dramatically at Fe3O4@SiO2/GO/SPE. Under the optimized experimental conditions tryptophan showed linear response over the range of 1.0-400.0 μM. The lower detection limit was found to be 0.2 μM for tryptophan. The practical application of the modified electrode was demonstrated by measuring the concentration of tryptophan in real samples
Electrochemical measurements of ascorbic acid based on graphite screen printed electrode modified with La3+/Co3O4 nanocubes transducer
Electrochemical characterization of ascorbic acid oxidation on a graphite screen printed electrode (SPE) modified with La3+/Co3O4nanocubes is performed by applying cyclic voltammetry (CV), chronoamperometry (CHA), and differential pulse voltammetry (DPV) techniques. Synthesized La3+/Co3O4nanocubes for SPE modification, La3+/Co3O4/SPE, enhance the ascorbic acid electrooxidation kinetics by reducing the anodic overpotential. Excellent La3+/Co3O4/SPE electrochemical properties provide sensitive ascorbic acid voltammetric determination with low detection limit, good stability and quick response towards electrooxidation of ascorbic acid as compared to bare SPE. Under optimized conditions, DPV current demonstrates a linear response for ascorbic acid over a concentration range of 1.0 to 900.0 mM with a correlation coefficient of 0.9997, and detection limit (LOD) (S/N = 3) = 0.3 mM. The proposed procedure offers a potential application for producing the sensor with good repeatability. Also, fast response of fabricated sensor can allow a real-time analysis of real samples
Optimization of chemical conditions for metabolites production by Ganoderma lucidum using response surface methodology and investigation of antimicrobial as well as anticancer activities
Ganoderma lucidum (G. lucidum) is a medicinal mushroom that is known for its ability to produce compounds with physiological effects on human health. This research was undertaken to amplify the production of bioactive components of G. lucidum under optimal cultivation conditions, obtained in a submerged state and utilized in solid state fermentation, with the purpose of enhancing antimicrobial and anticancer activities. The results indicated that titanium dioxide (TiO2 NPs), magnesium oxide nanoparticles (MgO2 NPs), and B6, along with glucose syrup and CLS syrups, were the most effective for producing GA, while wheat starch and whey protein, along with MgO2 NPs and B6 vitamin, stimulated polysaccharide production using the One Factor at a Time (OFAT) method. After screening, the response surface method (RSM) statistically indicated that the media containing 42.11 g/L wheat starch with 22 g/L whey protein and 50 g/L glucose syrup with 30 g/L CSL were found to be the best conditions for polysaccharide (21.47% of dry weight biomass) and GA (20.35 mg/g dry weight biomass) production, respectively. The moss of the fruit body of G. lucidum produced under optimal GA conditions had the highest diversity in flavonoids and phenolic acids and significant antimicrobial activity against Esherichia coli (E. coli) and Bacillus subtilis (B. subtilis). In addition, the IC50 levels of shell and stem of G. lucidum were 465.3 and 485.7 μg/mL, respectively, while the moss did not reach 50% inhibition. In the end, the statistical approaches utilized in this research to elevate the levels of bioactive components in the fruiting body of G. lucidum produced a promising natural source of antimicrobial and anticancer agents
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