This paper proposes a Langmuir probe–based diagnostics for plasma parameters inside gridded cathodes at high bias potentials in inertial electrostatic confinement devices. As the first step for the proof of concept, floating potential profiles were measured in deuterium and helium plasmas in a glow-discharge mode. The measurements with fusion-relevant cathode voltages up to 55 kV were carried out successfully. The results revealed that the positive potential buildup at the center ranges from 5% to 8% of the applied bias voltage to the gridded cathode, which is found to be much smaller than those in earlier works under cathode voltages lower than 5 kV. It was also shown that the floating potential profile is different significantly between deuterium and helium discharge plasmas.

Abstract The effects of foliar applied H2O2 on chlorophyll, carotenoids, the non-enzymatic defense system (ascorbic acid), malondialdehyde (MDA) hydrogen peroxide ( H2O2) and growth were assessed in roots and shoots of pea (Pisum sativum L.) plants exposed to excess cadmium. In addition, we evaluated the influences of H2O2 spraying on proline, soluble sugars and soluble proteins contents. Excessive cadmium treatment caused reduction in the growth parameters (dry mass, pods and seeds dry weights), chlorophyll and carotenoids contents, roots total free amino acids, roots soluble sugars as well as shoots and roots soluble proteins levels but increased total free amino acids and soluble sugars contents in shoots. Concentrations of hydrogen peroxide and MDA was enhanced under Cd treatment. The foliar treatment of H2O2 alleviated the detrimental effects generated under Cd treatment that represented as increment in pea growth. H2O2 spraying increased photosynthetic pigments, growth characteristics, soluble proteins, and ascorbic acid contents comparing to the control sets not receiving H2O2. Similarly, a higher up-regulation was detected in proline contents of Cd + H2O2 set than Cd group ones at 0.25 mM Cd. Contrarily, malondialdehyde (MDA), soluble sugars and total free amino acids contents of Cd + H2O2 set revealed a lower decrease than Cd group ones especially in roots. The results demonstrated that H2O2 treatment could inverse the harmful effects of cadmium on growth, through inducing the non-enzymatic defense system (ascorbate), proline accumulation, maintenance of chlorophyll in pea leaves and lowering the intensity of H2O2 and lipid peroxidation (MDA).

Abstract The effects of foliar applied H2O2 on chlorophyll, carotenoids, the non-enzymatic defense system (ascorbic acid), malondialdehyde (MDA) hydrogen peroxide ( H2O2) and growth were assessed in roots and shoots of pea (Pisum sativum L.) plants exposed to excess cadmium. In addition, we evaluated the influences of H2O2 spraying on proline, soluble sugars and soluble proteins contents. Excessive cadmium treatment caused reduction in the growth parameters (dry mass, pods and seeds dry weights), chlorophyll and carotenoids contents, roots total free amino acids, roots soluble sugars as well as shoots and roots soluble proteins levels but increased total free amino acids and soluble sugars contents in shoots. Concentrations of hydrogen peroxide and MDA was enhanced under Cd treatment. The foliar treatment of H2O2 alleviated the detrimental effects generated under Cd treatment that represented as increment in pea growth. H2O2 spraying increased photosynthetic pigments, growth characteristics, soluble proteins, and ascorbic acid contents comparing to the control sets not receiving H2O2. Similarly, a higher up-regulation was detected in proline contents of Cd + H2O2 set than Cd group ones at 0.25 mM Cd. Contrarily, malondialdehyde (MDA), soluble sugars and total free amino acids contents of Cd + H2O2 set revealed a lower decrease than Cd group ones especially in roots. The results demonstrated that H2O2 treatment could inverse the harmful effects of cadmium on growth, through inducing the non-enzymatic defense system (ascorbate), proline accumulation, maintenance of chlorophyll in pea leaves and lowering the intensity of H2O2 and lipid peroxidation (MDA).

Discovering new anticancer drugs and screening their efcacy requires a huge amount of resources and time-con‑ suming processes. The development of fast, sensitive, and nondestructive methods for the in vitro and in vivo detec‑ tion of anticancer drugs’ efects and action mechanisms have been done to reduce the time and resources required to discover new anticancer drugs. For the in vitro and in vivo detection of the efciency, distribution, and action mechanism of anticancer drugs, the applications of electrochemical techniques such as electrochemical cell chips and optical techniques such as surface-enhanced Raman spectroscopy (SERS) have been developed based on the nanostructured surface. Research focused on electrochemical cell chips and the SERS technique have been reviewed here; electrochemical cell chips based on nanostructured surfaces have been developed for the in vitro detection of cell viability and the evaluation of the efects of anticancer drugs, which showed the high capability to evaluate the cytotoxic efects of several chemicals at low concentrations. SERS technique based on the nanostructured surface have been used as label-free, simple, and nondestructive techniques for the in vitro and in vivo monitoring of the distribution, mechanism, and metabolism of diferent anticancer drugs at the cellular level. The use of electrochemical cell chips and the SERS technique based on the nanostructured surface should be good tools to detect the efects and action mechanisms of anticancer drugs

Aflatoxins (AFs) are a family of fungal toxins that produced in food and feed by two Aspergillus species (Aspergillus flavus and Aspergillus parasiticus). Several techniques have been reported for AFs detection including high-pressure liquid chromatography, enzyme-linked immunosorbent assay, surface plasmon resonance and recombinant immune blotting assay. But, these methods are disadvantaged because they consumed a long time for analysis; in addition, they required a piece of complicated and expensive equipment. Therefore, developing of inexpensive sensors with high selectivity and sensitivity for detecting of AFs levels without extensive sample preparation has received great attention. Several electrochemical AFs sensors have been reported; however, there is still a need for developing a new, simple and rapid electrochemical AFs sensor. Here, we have developed a new AFs sensor based on Au nanostructures/graphene nanosheets modified ITO substrate that could enhance the Raman effect and the electrochemical conductivity. The modified electrode was prepared based on layer-by-layer electrochemical deposition method. AFs antibody was immobilized onto the Au nanostructures/graphene nanosheets; then it was used as a probe for rapid, simple and cheap detection of AFs level using Raman spectroscopy and electrochemical techniques. Our results demonstrated that the developed system showed a simple, easy and sensitive sensor for monitoring low concentrations of AFB1 with a detection limit of about 6.9 pg/mL, also it allowed the determination of AFB1 in spiked food samples.

Hepatitis C virus (HCV) is a blood-borne virus that causes infectious chronic hepatitis. Egypt has the largest epidemic of HCV in the world, with about 14.7% of the Egyptian population. Thus, HCV, which could cause severe risks for human health including liver failure, becomes a public health concern for Egyptians. Development of highly selective and sensitive biosensors for accurate detection of HCV levels without extensive sample preparation has received great attention. The present work reported on developing a new rapid, highly selective and highly selective HCV-based biosensor for early detection of HCV-RNA extracted from clinical samples. The HCV-based biosensor was constructed by fabrication of gold nanodots/indium tin oxide substrate and followed by immobilization of a specific peptide nucleic acid (as bio-receptors) terminated with thiol group onto gold nanodots/indium tin oxide. The principle of the developed biosensor was based on the selective hybridization between the peptide nucleic acid and the HCV-RNA at the untranslated regions (5′-UTR). Raman spectroscopy and Square wave voltammetry techniques were used to monitor the interaction between the HCV-RNA and the immobilized peptide nucleic acid. The reported HCV-biosensor demonstrated a high capability to detect HCVRNA

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Spectrophotometric techniques has been applied for studying the kinetics and mechanistics between Ag+ and [IrCl6]2− reaction in aqueous acidic solutions at a constant ionic strength of 1.0 moldm−3. The naked eyes observation showed that the brownish color of [IrCl6]2− solution was rapidly vanishing with simultaneous appearance of a new dark-blue color on mixing solution of the oxidant with Ag+ ion electrolyte in either neutral or acidic media. The new color was persisted for a few seconds or minutes depending on the reaction conditions. Then, it began to fading out with time elapsing. This result means that the reaction occurs through two distinct stages. The spectral traces indicated the formation of binuclear intermediate complex at the initial fast stage [Ag+…ClIrCl52−] (with the rate constants k1 = 1.15 × 10−2 dm 3 mol−1 s−1; k−1 = 7.35 × 10−5 s−1, formation constant (K) = 1.56 × 102 dm 3 mol−1 and pseudo first- order rate constant (kobs) = 1.31 × 10−4 s−1 at [IrCl6]2− = 2.2 × 10−4, [H+] = 1.0 mol dm−3 and 30 °C. The initial rapid part was followed by a subsequent slow stage corresponding to the decomposition of the formed binuclear intermediate in the rate-determining step to give rise to the final oxidation products. The formation of such binuclear intermediate was found to be of acid-independent; nature; whereas its decomposition was dependent on the acid concentration with inverse fractional first-order in [H+]. This means that the binuclear decomposition is of acid-inhibition nature. In case of presence of a large excess of [Ag+] over that of [IrCl6]2−, Ir(0) nanoparticles was formed as confirmed by the XRD-spectra and TEM morphology. The kinetic parameters for the formation constants and decomposition rate constants of the binuclear complex have been evaluated and a suitable reaction mechanism for the overall redox reaction is suggested and discussed.

The goal of this study is to investigate the effect of a single dose of ethanol on the developing chick embryo.. Fertilized eggs were divided into five groups; a control group, and the other groups were injected in the air sac, before incubation with a single dose of 100 µl saline solution, 5%, 10% or 15% ethanol in saline solution. Results revealed growth retardation and malformations in different organs. Retinal cells were degenerated and cell death was induced in later stages of development. Levels of lipid peroxidation are significantly increased, levels of nitric oxide are fluctuated between an increase in the 5% ethanol treated group and a decrease in the 10% and 15% ethanol treated groups. Levels of the antioxidants, glutathione and vitamin C are significantly decreased at all doses of ethanol used except for a significant increase of glutathione in case of treatment with 10% ethanol. It is suggested that ethanol might exert its action through slowing down the rate of development during the early stages of incubation (two and four days), and later (six days) the action was probably through cellular damage via releasing free radicals and changing levels of nitric oxide concentration. Thus, findings of the current study demonstrate the direct toxic effects of a single dose of ethanol on developing embryos in general and on the eye in particular. Since all human embryos are vulnerable to any accidental alcohol toxixity, pregnant mothers are required to check up for alcohol abnormalities.