Electrochemical Oxidation of Methionine Mediated by a Fullerene-C60 Modified Gold Electrode

The usefulness of a C60-fullerene modified gold (Au) electrode in mediating the oxidation of methionine in the presence of potassium ions electrolyte has been demonstrated. During cyclic voltammetry, an oxidation peak of methionine appearing at þ1.0 V vs. Ag/AgCl was observed. The oxidation current of methionine is enhanced by about 2 times using a C60 modified gold electrode. The current enhancement is significantly dependent on pH, temperature and C60 dosage. Calibration plot reveals linearity of up to 0.1 mM with a current sensitivity of close to 50 mA L mol1 and detection limit of 8.2106 M. The variation of scan rate study shows that the system undergoes diffusion-controlled process. Diffusion coefficient and rate constant of methionine were determined using hydrodynamicmethod(rotating disk electrode) with values of 1.11105 cm2 s1 and 0.0026 cm s1 respectively for unmodified electrode while the values of diffusion coefficient and rate constant of methionine using C60 modified Au electrode are 5.7106 cm2 s1 and 0.0021 cm s1 respectivel

Using Modified Bessel Functions for Analysis of Nonlinear Effects in a MOS Transistor Operating in Moderate Inversion

This work was supported in part by the NSERC, Canada, in part by the Portuguese Foundation for Science and Technology under Project PESTOEEEI/UI0066/2015 and foRESTER Project PCIF/SSI/0102/2017, and in part by the Academy of Finland.This paper describes analysis of nonlinear effects in a MOS transistor operating in moderate inversion and saturation. The dependence of the drain current on the gate-source and drain-source voltages is described using a modified version of the 'reconciliation' model developed by Y. Tsividis. In the new model, the current components, which correspond to the terms depending exponentially on normalized gate-source or drain-source modulating sinusoidal voltages, are presented using modified Bessel functions. This approach allows one to find the first, second, and third harmonics of the drain current caused by the gate-source or drain-source voltage sinusoidal modulation and find also the intermodulation terms produced by these two modulating voltages. The results are applied to set the requirements to the gate-source and drain-source bias voltages in design of low-distortion and/or low-voltage amplifiers. It is shown that the realization of the stage with the zero value of third-order harmonic requires extremely tight tolerances for the threshold voltage. The suppression of intermodulation terms requires increased drain-source voltage. These recommendations are confirmed by simulations.authorsversionpublishe

Anaemia of inflammation preceding dyspnoea, dry cough and weight loss in primary pulmonary lymphoma

Introduction: There is little information in the literature on the early, sub-clinical stage and laboratory test results in patients with primary mucosa-associated lymphoid tissue (MALT) lymphoma of the lung, a rare disease. Case description: In a 75-year-old man, an open lung biopsy-confirmed diagnosis of primary pulmonary lymphoma was preceded by almost six months of anaemia of inflammatory disease and monocytosis without any pulmonary symptoms. When he developed a dry cough, increasing dyspnoea and marked weight loss, these changes deepened and became associated with reactive thrombocytosis; markedly increased ferritin and C-reactive protein (positive acute-phase reactants), as well as reduced albumin and transferrin (negative acute-phase reactants). Globulins increased, due to an increase in the alpha1, alpha2 and gamma fractions, and mild hyponatraemia developed due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH) secondary to the intrathoracic disease. All these changes were completely reversible following successful treatment and complete remission. Conclusion: The previously unreported detailed laboratory features of early, sub-clinical and advanced primary pulmonary lymphoma are presented. When a potentially susceptible patient develops an unexplained anaemia of inflammatory disease, primary pulmonary lymphoma should be added to the differential diagnosis

A Novel Low Delay High-Voltage Level Shifter with Transient Performance Insensitive to Parasitic Capacitance and Transfer Voltage Level

In this paper, a new high-voltage level shifter (HVLS) structure is proposed, which has a significantly improved transient response over existing structures. To overcome signal transfer delay of the conventional HVLS caused by parasitic capacitance due to high-voltage MOSFETs, this structure employs a novel circuit module “inverse Schmitt trigger” to drive the pull-up transistors of conventional HVLS. As a result, the “Miller Plateau” caused by parasitic capacitance can be minimized. Hence, the overall transfer delay of the structure is significantly reduced. The simulation results based on SPECTRE and 0.5 μm high-voltage CMOS process show that compared to other currently available structures whose transfer delays are several nanoseconds on average, the proposed structure is able to provide a nanosecond transfer delay without using large boost capacitors which are impractical to be integrated or using complex logic units which decrease reliability of circuit. Also, the typical transfer delay of the proposed structure is a constant 1.3 ns, which is irrelevant to parasitic capacitance and insensitive to transfer voltage level

Raising the standards of patient-centered outcomes research in myelodysplastic syndromes : Clinical utility and validation of the subscales of the QUALMS from the MDS-RIGHT project

Background Clinical decision-making for patients with myelodysplastic syndromes (MDS) is challenging, and both disease and treatment effects heavily impact health-related quality of life (HRQoL) of these patients. Therefore, disease-specific HRQoL measures can be critical to harness the patient voice in MDS research. Methods We report a prospective international validation study of the Quality of Life in Myelodysplasia Scale (QUALMS) with a main focus on providing information on the psychometric characteristics of its three subscales: physical burden (QUALMS-P), emotional burden (QUALMS-E), and benefit finding (QUALMS-BF). The analysis is based on patients enrolled from three European countries and Israel, participating to the MDS-RIGHT Project. The scale structure and psychometric properties of the QUALMS were assessed. Results Overall, 270 patients with a median age of 74?years were analyzed and the majority of them (60.3%) had a low MDS-Comorbidity Index score. Results of the confirmatory factor analysis supported the underlying scale structure of the QUALMS, which, in addition to a total score, includes three subscales: QUALMS-P, QUALMS-E, and the QUALMS-BF. The QUALMS-P exhibited the highest Cronbach's alpha coefficients. Discriminant validity analysis indicated good results with the QUALMS-P and QUALMS-E distinguishing between patients with different performance status, comorbidity, anemia, and transfusion dependency status. No floor and ceiling effects were observed. Responsiveness to change analysis supported the validity of the measure. Patients with a hemoglobin (Hb) level of Conclusions Our study provides additional validation data on the QUALMS from the international MDS-RIGHT Project. The use of this disease-specific HRQoL measure may contribute to raise quality standards of patient-centered outcomes research in MDS

L-Cysteine determination in embryo cell culture media using Co (II)-phthalocyanine modified disposable screen-printed electrodes

Thiol-containing compounds such as L-cysteine have been demonstrated to play an important role in metabolism and cellular growth, acting as powerful antioxidants. Consequently, their analytical determination in biological media has received a considerable amount of attention. In this work, an electrochemical sensor for the accurate electroanalytical determination of L-cysteine is proposed, based upon a Co(II)-phthalocyanine bulk modified disposable screen-printed graphite electrode (CoPc-SPE). Cyclic (CV) and Square Wave (SWV) voltammetry experiments have demonstrated an excellent electrocatalytic activity towards the electrochemical oxidation of L-cysteine using CoPc-SPEs within optimum neutral or basic pH. Moreover, the SWV response of L-cysteine is found to exhibit a linear range of 2.6–200 μM, with a low limit of detection of 4 μM (S/N = 3) and a sensitivity of 0.78 μA cm− 2 μM− 1. Coefficient of variation for reproducibility and repeatability of L-cysteine determination using the CoPc-SPE are 3 and 0.4%, respectively. The effect of inherent interferences such as naturally occurring amino acids, cystine and cysteic acid has been also evaluated. Finally, the applicability of the L-cysteine electrochemical sensor based upon CoPc-SPEs has been successfully demonstrated for the first time for the assessment of L-cysteine in a complex embryo cell culture medium