An Alternative to Monte Carlo Simulation Method

The quantification and propagation of uncertainty is a growing discipline, with applications within practically all sciences. Uncertainties are present in every prediction model of each discipline (natural, structural, biological, etc), since an exact and perfect definition of geometry, boundary conditions, material properties, initial conditions and excitations (among others) is rarely possible. A common and robust approach to perform the propagation of uncertainties is the Monte Carlo method, which usually implies running a large number of simulations. Complex systems, where uncertainty propagation is particularly interesting, require time expensive computations, and large memory and storage capacities in order to process such amount of data. Even thousands of runs of a slightly non-linear model with a few degrees of freedom could take a considerable time, despite the use of state-of-the-art solvers and parallelization techniques. In this work, a methodology that could allow the reduction of the number of simulations is discussed. The idea of the method is to perform a parametric sweep for a certain parameter X to be considered stochastic, then assign probabilities (according to a previously selected cumulative probability density function) to the values of X, and finally map the corresponding probability values to the target variables. Hence, the probability density function of the target variables could be estimated. Within this work, the theory and implementation of the proposed method are discussed and application examples are provided.Fil: Ballaben, Jorge Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Sur; ArgentinaFil: Goicoechea, Hector Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Rosales, Marta Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaXII Congreso Argentino de Mecánica ComputacionalSan Miguel de TucumánArgentinaAsociación Argentina de Mecánica Computaciona

MATLAB in electrochemistry: A review

International audienceMATLAB (MATrix LABoratory) is a multi-paradigm numerical computing environment and fourth-generation programming language. MATLAB allows matrix manipulations, plotting of functions and data, implementation of algorithms, creation of user interfaces and interfacing with programs written in other languages, including C, C ++ , Java, Fortran and Python. Electrochemistry is a branch of chemistry that studies the relationship between electricity, as a measurable and quantitative phenomenon, and identifiable chemical change, with either electricity considered an outcome of a particular chemical change or vice versa. MATLAB has obtained a wide range of applications in different fields of science and electrochemists are also using it for solving their problems which can help them to obtain more quantitative and qualitative information about systems under their studies. In this review, we are going to cast a look on different applications of MATLAB in electrochemistry and for each section, a number of selected articles published in the literature will be discussed and finally, the results will be summarized and concluded

Matrix augmentation as an efficient method for resolving interaction of bromocriptine with human serum albumin: trouble shooting and simultaneous resolution

This work reports the results of an interesting study related to the investigation of interactions of bromocriptine (BCP) with human serum albumin (HSA) by mathematicall modelling of voltammetric and spectroscopic data into an augmented data matrix and its resolution by multivariate curve resolution-alternating least squares (MCR-ALS). The quality of the results obtained by MCR-ALS was examined by MCR-BANDS and its outputs confirmed the absence of rotational ambiguities in the MCR-ALS results. BCP-HSA interactions were also modeled by molecular docking methods to verify the results obtained from experimental sections and fortunately, they were compatible. Hard modeling of the experimental data by EQUISPEC helped us to calculate the binding constant of the complex formed from BCP-HSA interactions which was in a good agreement with that of calculated from direct analysis of the experimental data. Finally, with the help of two different amperometric measurements based on BCP-HSA interactions a novel electroanalytical method was developed for biosensing of HSA in serum samples.Fil: Jalalvand, Ali R.. Kermanshah University of Medical Sciences; IránFil: Ghobadi, Sirous. Kermanshah University of Medical Sciences; IránFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Faramarzi, Elahe. Kermanshah University of Medical Sciences; IránFil: Mahmoudi, Majid. Kermanshah University of Medical Sciences; Irá

Multi-level data fusion strategies for modeling three-way electrophoresis capillary and fluorescence arrays enhancing geographical and grape variety classification of wines

Capillary electrophoresis with diode array detection (CE-DAD) and multidimensional fluorescence spectroscopy (EEM) second-order data were fused and chemometrically processed for geographical and grape variety classification of wines. Multi-levels data fusion strategies on three-way data were evaluated and compared revealing their advantages/disadvantages in the classification context. Straightforward approaches based on a series of data preprocessing and feature extraction steps were developed for each studied level. Partial least square discriminant analysis (PLS-DA) and its multi-way extension (NPLS-DA) were applied to CE-DAD, EEM and fused data matrices structured as two-way and three-way arrays, respectively. Classification results achieved on each model were evaluated through global indices such as average sensitivity non-error rate and average precision. Different degrees of improvement were observed comparing the fused matrix results with those obtained using a single one, clear benefits have been demonstrated when level of data fusion increases, achieving with the high-level strategy the best classification results.Fil: Ríos Reina, Rocío. Universidad de Sevilla; EspañaFil: Azcarate, Silvana Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Camiña, José Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; Argentin

Parallel factor analysis of 4.2K excitation-emission matrices for the direct determination of dibenzopyrene isomers in coal-tar samples with a cryogenic fiber optic probe coupled to a commercial spectrofluorimeter

Several studies have shown high concentrations of polycyclic aromatic hydrocarbons (PAHs) in living spaces and soil adjacent to parking lots sealed with coal-tar-based products. Recent attention has been paid to the presence of seven PAHs in coal-tar samples ? namely, benz[a]anthracene, benzo[k]-fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene, chrysene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene ? and their association to significant increases in estimated excess lifetime cancer risk for nearby residents. Herein, we present an analytical approach to screen the presence of five highly toxic, high-molecular weight PAHs (HMW-PAHs) in coal-tar samples. These include dibenzo[a,l]pyrene, dibenzo[a,i]pyrene, dibenzo[a,e]pyrene, dibnezo[a,h]pyrene and naphtho[2,3-a]pyrene. Their direct analysis ? no without chromatographic separation ? - in a reference coal-tar sample is made possible with the combination of excitation-emission matrices (EEMs) and parallel-factor analysis (PARAFAC). EEMs are recorded at 4.2 K with the aid of a cryogenic fiber optic probe and a commercial spectrofluorimeter. The simplicity of the experimental procedure and the excellent analytical figures of merit demonstrate the screening potential of this environmentally friendly approach for the routine analysis of numerous coal-tar samples.Fil: Moore, Anthony F. T.. University of Central Florida; Estados UnidosFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Barbosa, Fernando Jr.. Universidade de Sao Paulo; BrasilFil: Campiglia, Andres D.. University of Central Florida; Estados Unido

Mathematical modeling of interactions of cabergoline with human serum albumin for biosensing of human serum albumin

In this work, we are going to study the interactions of cabergoline (CBG) with human serum albumin (HSA) by mathematical modeling of voltammetric and spectroscopic data. To achieve this goal, voltammetric and spectroscopic data will be augmented into a data matrix which will be resolved by multivariate curve resolution-alternating least squares (MCR-ALS) as a powerful chemometric tool. Then, the quality of the data fitting by MCR-ALS will be examined by MCR-BANDS to ensure about the absence of the rotational ambiguities in the results. Molecular docking will also be used to model the interactions of CBG with HSA for verifying the results obtained from experimental methods. Hard-modeling of the experimental data will be performed by EQUISPEC to compute the binding constant of the complex formed from the interactions of CBG with HSA for verifying the binding constant obtained by direct analysis of the experimental data. Finally, two chrono-amperometric measurements based on CBG-HSA interactions will be performed to develop a novel electroanalytical method for determination of electro-inactive HSA.Fil: Jalalvand, Ali R.. Kermanshah University of Medical Sciences; IránFil: Ghobadi, Sirous. Razi University; IránFil: Akbari, Vali. Razi University; Irán. Kermanshah University of Medical Sciences; IránFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Faramarzi, Elahe. Kermanshah University of Medical Sciences; IránFil: Mahmoudi, Majid. Kermanshah University of Medical Sciences; Irá

Applications of liquid-phase microextraction procedures to complex samples assisted by response surface methodology for optimization

This review presents applications of liquid phase microextraction (LPME) for extracting analytes in complex samples. This process has been introduced to simplify the extraction methods, and enhance the selectivity, sample cleanup and efficiency, allowing the extraction of a wide variety of analytes. The revision was focused on those works in which the performance of the technique was optimized by the response surface methodology (RSM). Firstly, a description of the different LPME systems is presented. Then, a brief explanation of the most popular tools applied for optimization is displayed. After that, the results of a literature search of the works reported from 2009 to 2019 based on the implementation of microextraction supported by experimental design and optimization can be found summarized in a table. Finally, an illustrative example providing the necessary information to carry out this kind of work is presented. A list of the most popular software available to apply RSM is also presented.Fil: Carabajal, Maira Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Teglia, Carla Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Cerutti, Estela Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Culzoni, Maria Julia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; Argentin

The first attempt on fabrication of a nano-biosensing platform and exploiting first-order advantage from impedimetric data: application to simultaneous biosensing of doxorubicin, daunorubicin and idarubicin

In this work, for the first time, we have developed a novel and very interesting electroanalytical methodology assisted by first-order multivariate calibration (MVC) for simultaneous determination of doxorubicin (DX), daunorubicin (DN) and idarubicin (ID) as three chemotherapeutic drugs at simulated physiological conditions. A sever overlapping was observed among signals of the three drugs which hindered us for simultaneous determination of them by conventional electroanalytical techniques. Therefore, we had to assist our method by chemometric approaches to develop a novel method for simultaneous determination of DX, DN and ID. Among the existing electroanalytical methods, electrochemical impedance spectroscopy (EIS) due to its high sensitivity was chosen. After individual calibration of the three drugs with the EIS data, a set of calibration samples was designed which was used to develop several first-order MVC models by partial least squares (PLS), continuum power regression (CPR), radial basis function-partial least squares (RBF-PLS), RBF-artificial neural network (RBF-ANN) and least squares-support vector machines (LS-SVM) as linear and non-linear chemometric algorithms. Then, performance of the developed MVC models in predicting concentrations of DX, DN and ID in synthetic samples was compared to choose the best model for the analysis of real samples. Our records confirmed more superiority of RBF-PLS algorithm than the other developed models which motivated us to choose it for the analysis of real samples. Fortunately, the results of the RBF-PLS in the analysis of real samples towards simultaneous determination DX, DN and ID was acceptable.Fil: Soleimani, Shokoufeh. Kermanshah University Of Medical Sciences; IránFil: Arkan, Elham. Kermanshah University Of Medical Sciences; IránFil: Farshadnia, Tooraj. Kermanshah University Of Medical Sciences; IránFil: Mahnam, Zahra. Kermanshah University Of Medical Sciences; IránFil: Jalili, Faramarz. Kermanshah University Of Medical Sciences; IránFil: Goicoechea, Hector Casimiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; ArgentinaFil: Jalalvand, Ali R.. Kermanshah University Of Medical Sciences; Irá

Application of Quantum Cascade Laser-Infrared Spectroscopy and Chemometrics for In-Line Discrimination of Coeluting Proteins from Preparative Size Exclusion Chromatography

An external-cavity quantum cascade laser (EC-QCL)-based flow-through mid-infrared (IR) spectrometer was placed in line with a preparative size exclusion chromatography system to demonstrate real-time analysis of protein elutions with strongly overlapping chromatographic peaks. Two different case studies involving three and four model proteins were performed under typical lab-scale purification conditions. The large optical path length (25 μm), high signal-to-noise ratios, and wide spectral coverage (1350 to 1750 cm-1) of the QCL-IR spectrometer allow for robust spectra acquisition across both the amide I and II bands. Chemometric analysis by self-modeling mixture analysis and multivariate curve resolution enabled accurate quantitation and structural fingerprinting across the protein elution transient. The acquired concentration profiles were found to be in excellent agreement with the off-line high-performance liquid chromatography reference analytics performed on the collected effluent fractions. These results demonstrate that QCL-IR detectors can be used effectively for in-line, real-time analysis of protein elutions, providing critical quality attribute data that are typically only accessible through time-consuming and resource-intensive off-line methods.Fil: Akhgar, Christopher K.. Vienna University of Technology; AustriaFil: Ebner, Julian. Vienna University of Technology; AustriaFil: Alcaraz, Mirta R.. Institute Of Chemical Technologies And Analytics; AustriaFil: Kopp, Julian. Vienna University of Technology; AustriaFil: Goicoechea, Hector Casimiro. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Spadiut, Oliver. Vienna University of Technology; AustriaFil: Schwaighofer, Andreas. Vienna University of Technology; AustriaFil: Lendl, Bernhard. Vienna University of Technology; Austri

Chemometrical-electrochemical investigation for comparing inhibitory effects of quercetin and its sulfonamide derivative on human carbonic anhydrase II: Theoretical and experimental evidence

This paper reports results of a valuable study on investigation of inhibitory effects of the sulfonamide derivative of quercetin (QD) on human carbonic anhydrase II (CA-II) by electrochemical and chemometrical approaches. To achieve this goal, a glassy carbon electrode (GCE) was chosen as the sensing platform and different electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) were used to investigate and comparing inhibitory effects of quercetin (Q) and QD on CA-II. By the use of EQUISPEC, SPECFIT, SQUAD and REACTLAB as efficient hard-modeling algorithms, bindings of Q and QD with CA-II were investigated and the results confirmed that the QD inhibited the CA-II stronger than Q suggesting a highly relevant role of QD's-SO2NH2 group in inhibiting activity and also was confirmed by docking studies. Finally, a novel EIS technique based on interaction of Q and CA-II was developed for sensitive electroanalytical determination of CA-II and in this section of our study, the sensitivity of the developed electroanalytical methodology was improved by the modification of the GCE was with multi-walled carbon nanotubes-ionic liquid.Fil: Khodarahmi, Reza. Kermanshah University of Medical Sciences; IránFil: Khateri, Shaya. Kermanshah University of Medical Sciences; IránFil: Adibi, Hadi. Kermanshah University of Medical Sciences; IránFil: Nasirian, Vahid. State University of Louisiana; Estados UnidosFil: Hedayati, Mehdi. Kermanshah University of Medical Sciences; IránFil: Faramarzi, Elahe. Kermanshah University of Medical Sciences; IránFil: Soleimani, Shokoufeh. Kermanshah University of Medical Sciences; IránFil: Goicoechea, Hector Casimiro. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas. Laboratorio de Desarrollo Analítico y Quimiometría; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Jalalvand, Ali Reza. Kermanshah University Of Medical Sciences; Irá