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Exponential Continuous Non-Parametric Neural Identifier With Predefined Convergence Velocity

IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 1049-1060页

作者： Mariana Ballesteros Rita Q.Fuentes-Aguilar Isaac Chairez Instituto Politécnico Nacional Centro de Innovación y Desarrollo Tecnológico en Cómputo Unidad Profesional Interdisciplinaria de Biotecnología 07340Mexico CityMexico Tecnológico de Monterrey School of Engineering and SciencesZapopanJalisco 45138Mexico department of bioprocesses UPIBIInstituto Politécnico Nacional07340Mexico City

This paper addresses the design of an exponential function-based learning law for artificial neural networks(ANNs)with continuous dynamics.The ANN structure is used to obtain a non-parametric model of systems with uncertainties,which are described by a set of nonlinear ordinary differential equations.Two novel adaptive algorithms with predefined exponential convergence rate adjust the weights of the ANN.The first algorithm includes an adaptive gain depending on the identification error which accelerated the convergence of the weights and promotes a faster convergence between the states of the uncertain system and the trajectories of the neural identifier.The second approach uses a time-dependent sigmoidal gain that forces the convergence of the identification error to an invariant set characterized by an ellipsoid.The generalized volume of this ellipsoid depends on the upper bounds of uncertainties,perturbations and modeling errors.The application of the invariant ellipsoid method yields to obtain an algorithm to reduce the volume of the convergence region for the identification error.Both adaptive algorithms are derived from the application of a non-standard exponential dependent function and an associated controlled Lyapunov function.Numerical examples demonstrate the improvements enforced by the algorithms introduced in this study by comparing the convergence settings concerning classical schemes with non-exponential continuous learning methods.The proposed identifiers overcome the results of the classical identifier achieving a faster convergence to an invariant set of smaller dimensions.

关键词： Exponential Lyapunov functions learning laws non-parametric identifier predefined convergence rate

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Output Second-order Sliding-mode Control for a Gecko Biomimetic Climbing Robot

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Journal of Bionic Engineering 2019年第4期16卷 633-646页

作者： David Cruz-Ortiz Mariana Ballesteros-Escamilla Isaac Chairez Alberto Luviano SEPl UPIITAInstitute Politecnico NationalAv.Institute Politecnico National 258007340Mexico bioprocesses department UPIBIInstitute Politecnico NationalAv.Acueducto 55007340Mexico

The aim of this study is to propose the output controller to solve the execution of the gait sequence for Gecko Bio-inspired Robotic Devices (GBRDs).The Twisting Controller (TC) serves as basis of the tracking trajectory designed algorithm.The TC uses both the tracking error and its estimated derivative,which is calculated by a set of distributed Super-Twisting Algorithms (STAs).Each STA is implemented as a robust and exact differentiator.The output-based controller structure corresponds to a sort of decentralized form for robotic devices.Consequently,each articulation is controlled by an independent TC.A set of proposed references trajectories reproduce the gait cycle of a Real Gecko-Lizard (RG-L).The reference trajectories are proposed as the superposition of sigmoid functions ful-filling the conditions of the Bezzier polynomials.Numerical simulations evaluate the GBRD movement enforced by the suggested controller in the horizontal as well as the vertical gaits.An own 3D printed GBRD is the experimental platform aimed to test the distributed controller.Two controlled vacuum pumps are used to adhere the GBRD to the wall surfaces.A set of experimental validations confirm the robustness and the reliability of the proposed controller when its performance is compared with classical output feedback controllers.

关键词： gecko robot biomimetic output-based controller twisting controller Super-Twisting Algorithm(STA)

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Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk

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Asian Pacific Journal of Tropical Medicine 2018年第12期11卷 676-681页

作者： Adriana Méndez-Flores Ayerim Hérnandez-Almanza Aidé Sáenz-Galindo Jesús Morlett-Chávez Cristóbal N Aguilar Juan Ascacio-Valdés bioprocesses and Bioproducts Research Group Food Research Department School of Chemistry Autonomous University of Coahuila Organic Chemistry department School of Chemistry Autonomous University of Coahuila Molecular Biology Laboratory School of Chemistry Autonomous University of Coahuila

Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.

关键词： Mexican variety rambutan Ultra-sound assisted extraction Antioxidant polyphenolic compounds HPLC/ESI/MS

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Use of Prosopis laevigata Seed Gum and Opuntia ficus-indica Mucilage for the Treatment of Municipal Wastewaters by Coagulation-Flocculation

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Natural Resources 2012年第2期3卷 35-41页

作者： Luis G. Torres Sandra L. Carpinteyro-Urban department of bioprocesses Unidad Profesional Interdisciplinaria de Biotecnología UPIBI-Instituto Politécnico Nacional Mexico

Prosopis laevigata and Opuntia ficus-indica grow in arid and semiarid regions of Mexico and other countries. Both produce biopolymers with interesting characteristics from the rheological point of view as well as because of their coagulating-flocculating capabilities. Prosopis produce galactomannans inside the endosperm, very similar to those found in guar, locust bean, and tara gums. Opuntia sp. produces mucilage that contains polygalacturonic acid and five neutral sugars. Prosopis seed gum has not been proposed to be used as coagulant-flocculant before. In the case of Opuntia mucilage, some authors have suggested its use in the treatment of waters, using either the mucilage or the whole cladode powder. The use of these products in the treatment of municipal or even industrial wastewaters could give rise to diverse benefits. From the environmental point of view, treated waters with neither Fe nor Al, nor synthetic polymers would be obtained (with less toxicity risk). Besides, the produced sludges would be smaller in amount, with better biodegradability, and lower metals content. From the economical point of view, the use of these biopolymers would give an added value to the Opuntia and Prosopis culture in Mexico, helping small communities to enhance their incomes by producing environmental-friendly products. This work shows that both Prosopis galactomannan and Opuntia mucilage can be used to treat municipal wastewaters with an initial organic charge of about 827 mg/L as COD by the coagulation-flocculation process, with COD removals for the mesquite seed gum of up to 90% (pH 10, dose of 75 mg/L) and of 60% (pH 7, doses of 50 and 150 mg/L). In the case of mucilage, 65% of the initial COD was removed at pH 10 (dose of 50 mg/L). These figures are very promising for the treatment of wastewaters, with environmental-friendly products.

关键词： Biopolymers Coagulation Flocculation Opuntia ficus Mucilage Prosopis laevigata Seed Gum Wastewaters

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Total phenolic content,in vitro antioxidant activity and chemical composition of plant extracts from semiarid Mexican region

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Asian Pacific Journal of Tropical Medicine 2015年第2期8卷 104-111页

作者： Jorge E.Wong-Paz Juan C.Contreras-Esquivel Raúl Rodríguez-Herrera María L.Carrillo-Inungaray Lluvia I.López Guadalupe V.Nevárez-Moorillón Cristóbal N.Aguilar Laboratory of bioprocesses and Natural Products Food Research DepartmentSchool of ChemistryUniversidad Autónoma de CoahuilaSaltillo25280México Laboratory of Biochemistry Multidisciplinary Academic Unit-HuastecaUniversidad Autónoma de San Luis Potosí79060Cd.VallesS.L.P.Mexico department of Microbiology School of ChemistryUniversidad Autónoma de Chihuahua31125 ChihuahuaMexico

Objective:To determine the extraction suitable conditions of total phenolic content(TPC) by heat-reflux system,antioxidant activities and HPLC characterization of the aqueous-ethanolic extracts of Jatropha dioica(J.dioica)(Dragon's blood).Flourensia cernua(F.cernua)(Tar bush).Eucalyptus camaldulensis(E.camaldulensis)(Eucalyptus) and Turnera diffusa(T.diffusa)(Damiana).Methods:TPC was evaluated by the well-known colorimetric assay using FolinCiocalteu reagent.The antioxidant activities were assayed by three methods based on scavenging of DPPH,ABTS and by lipid oxidation inhibition.The chemical composition of the extracts obtained was subject to HPLC analysis.Results:TPC in the plant extracts ranged from 2.3 to14.12 mg gallic acid equivalents/g for J.dioica and E.camaldulensis,respectively.The plant extracts of F.cernua,E.camaldulensis and T.diffusa showed similar strong antioxidant activities on scavenging of DPPH and lipid oxidation inhibition.In contrast,J.dioica extracts had lowest potential antioxidant in three assays used.HPLC assay showed the presence of several phenolic compounds in the extracts used.Conclusions:The results obtained suggest that F.cernua,E.camaldulensis and T.diffusa are potential sources to obtain bioactive phenolic compounds with high antioxidant properties which can be used in the factories as antioxidant agents or for treatments in diseases.

关键词： Plant-extracts Polyphenols Natural antioxidants Mexican plants Heat-reflux system

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Trehalose and Sucrose Osmolytes Accumulated by Algae as Potential Raw Material for Bioethanol

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Natural Resources 2011年第3期2卷 173-179页

作者： Ma.del Pilar Bremauntz Luis G.Torres-Bustillos Rosa-Olivia Canizares-Villanueva Enrique Duran-Paramo Luis Fernández-Linares Laboratory of bioprocesses Department of BioprocessesUnidad Profesional Interdisciplinaria de Biotecnologia UPIBI-Instituto Politecnico NacionalMexico CityMexico Departamento de Biotecnologia y Bioingenieria Centro de Investigacion y de Estudios Avanzados-IPNMexico CityMexico

Currently, obtaining sustainable fuels, such as biodiesel and bioethanol, from cheap and renewable materials is a challenge. In recent years, a new approach being developed consists of producing, sugars from algae by photosynthesis. Sugar accumulation can be increased under osmotic stress (osmoregulation). The aim of this study is to show the pro-duction of sugars from algae, isolated from natural sources, and the effect of osmotic stress on fermentable sugars ac-cumulation. Strain isolation, production of sugars from each alga and the effect of osmotic stress on growth and sugar production are described. Twelve algal strains were isolated, showing growths between 0.6 and 1.8 g of biomass dry weight /L, all with production of intracellular and extracellular sugars. The strain identified as Chlorella sp. showed an increase in sugar production from 23.64 to 421 mg of sugars/g of biomass dry weight after 24 h of osmotic stress with 0.4 M NaCl. Sucrose and trehalose, both fermentable sugars, were the compatible osmolytes accumulated in response to the osmotic stress. The isolated strains are potential producers of fermentable sugars, using the photosynthetic pathway and osmotic stress.

关键词： Algae Biofuels Osmoregulators Carbohydrates Bioethanol

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Impact of simulated in vitro gastrointestinal digestion on bioactive compounds,bioactivity and cytotoxicity of melon (Cucumis melo L. inodorus) peel juice powder

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Food Bioscience 2022年第3期47卷 1358-1367页

作者： Ricardo Gómez-García Ana A.Vilas-Boas Manuela Machado Débora A.Campos Cristóbal N.Aguilar Ana R.Madureira Manuela Pintado Universidade Católica Portuguesa CBQF-Centro de Biotecnologia e Química Fina – Laboratório AssociadoEscola Superior de BiotecnologiaRua Diogo Botelho 13274169-005PortoPortugal BBG-DIA.bioprocesses and Bioproducts Group.Food Research department School of ChemistryAutonomous University of CoahuilaSaltilloCoahuilaMexico

The objectives of this research work were to evaluate the effect of in vitro gastrointestinal digestion (GIT) on melon peel juice (MPJ) powder from fruit processing industry by-products,considering (i) the recovery and accessibility indexes,(ii) the changes on antioxidant activity,and (iii) the prebiotic effect.Throughout exposition to GIT conditions a decrease on the total phenolic content (TPC = 65.31%) and antioxidant activity by ABTS = 39.77% and DPPH = 45.91% were observed.However,these both parameters exhibited stable accessibility,accounting with 81.89%,76.55%,and 54.07% for TPC,ABTS and DPPH,respectively.After gastrointestinal digestion,the non-absorbed fraction exhibited a positive impact on the growth of Bifidobacterium and Lactobacillus strains,possibly associated with the high content of simple sugar (glucose and fructose).This fraction also showed to be safe on Caco-2 intestinal cells.These findings suggest that MPJ might be used as a potential food functional ingredient.

关键词： Melon by-products Functional ingredients Phenolic antioxidants Simulated digestion Prebiotic effect

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Osmotic Stress Effect over Carbohydrate Production in a Native Starin of Scenedesmus sp.

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Natural Resources 2014年第1期5卷 5-9页

作者： Pilar Bremauntz Luis C.Fernandez-Linares Rosa O.Canizares-Villanueva Laboratory of bioprocesses Department of BioprocessesUnidad Profesional Interdisciplinaria de Biotecnologia(UPIBI)Instituto Politecnico NacionalMexicoD.F.Mexico Departamento de Biotecnologia y Bioingenieria Centro de Investigacion y de Estudios AvanzadosInstituto Politecnico NacionalMexicoD.F.Mexico

The production of biofuels is currently presented as a possible answer in the search for sustainable alternatives for the total or partial substitution of fossil fuels. One of the most successful biofuels that have been developed is bioethanol. However, bioethanol production has been limited since it relies on the use of sugar cane or cereals. These materials are important sources of food and their demand as both a biofuel and a foodstuff has led to the price increase and may lead to possible shortages. Our group has focused on searching for native microalgae as sources of carbohydrates and bioethanol, with the goal of finding a sustainable source of bioethanol. Currently, twelve different strains which reach growth rates between 0.7 - 1.8 g/L and present carbohydrate production under osmotic shock conditions have been isolated. In this work, we demonstrate the results obtained with the Chlorella sp. [1] strain and the results obtained with the Scenedesmus sp. strain. The Scenedesmus sp. strain showed an increase in the production from 22 to 650 mg/sugar/g of biomass (dry weight), after 24 hours of osmotic shock with 0.1 M NaCl. The osmolytes which were produced after osmotic shock were identified as sucrose and trehalose, both of which are fermentable. These results demonstrate that this strain, through the photosynthetic pathway and osmotic shock, is a potential source of fermentable sugars.

关键词： Biofuels Bioethanol Microalgae Scenedesmus sp. Carbohydrates

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Recent trends and technical advancements in biosensors and their emerging applications in food and bioscience

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Food Bioscience 2022年第3期47卷 1023-1050页

作者： Oluwatosin E.Bankole Deepak Kumar Verma Mónica L.Chávez González Juan Guzmán Ceferino JoséSandoval-Cortés Cristóbal N.Aguilar department of Chemical Sciences Faculty of Science and Science EducationAnchor UniversityLagos StateNigeria Agricultural and Food Engineering department Indian Institute of Technology KharagpurKharagpur721302West BengalIndia bioprocesses Research Group Food Research DepartmentSchool of ChemistryUniversidad Autonoma de CoahuilaUnidad Saltillo25280CoahuilaMexico Los Ríos Multidisciplinary Academic Division Universidad Juárez Autónoma de TabascoTabascoMexico department of Analytical Chemistry School of ChemistryUniversidad Autonoma de CoahuilaUnidad Saltillo25280CoahuilaMexico

Biosensor development has recently advanced as a result of their strong and indisputable uses as analytical methods in a variety of sectors,including medicine,food industry,environmental monitoring,metabolism,agriculture,military,and security.The popularity of biosensors as devices for a variety of applications may be ascribed to their distinct advantages of fast or rapid analysis,high sensitivity,minimal sample demand and preparation,and no need for the specific skill of operation that traditional analytical procedures require.We attempted to update earlier studies in this study by incorporating other materials that have been in use but have received less attention,such as carbon nano-onions(CNOs),metal-organic frameworks(MOFs),and biopolymers for biosensor manufacturing and design based on their unique properties.The assessment also took into account applicable applications in many sectors.Although considerable progress has been made in the application of biosensors,there is still a need for research development and enhancement,particularly in transforming most of the laboratory experiments that have already been published into portable on-site and implementable in the public domains.

关键词： Biosensors Nanotechnology Nano-materials Food quality and safety Food snd biomedical industry Industrial application

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Use of wastes from the tea and coffee industries for the production of cellulases using fungi isolated from the Western Ghats of India

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Systems Microbiology and Biomanufacturing 2021年第1期1卷 33-41页

作者： S.A.Saldana-Mendoza J.A.Ascacio-Valdes A.S.Palacios-Ponce J.C.Contreras-Esquivel R.Rodriguez-Herrera H.A.Ruiz J.L.Martinez-Hernandez S.Sugathan C.N.Aguilar bioprocesses and Bioproducts Research Group Food Research DepartmentAutonomous University of Coahuila25280 SaltilloMexico Faculty of Engineering in Mechanics and Production Sciences Polytechnic School of LitoralESPOLCampus Gustavo Galindo Km.30.5 Vía PerimetralP.O.Box 09-01-5863GuayaquilEcuador Microbiology Division Jawaharial Nehru Botanical Garden and Research InstitutePalodeThiruvananthapuramKerala 695562India

In this study,coffee pulp(Coffea arabica)and green tea(Camellia sinensis)residues were characterized for use as a substrate of solid-state fermentation for cellulases production.The invasion rate was evaluated,as well as cellulases production by strains of Aspergillus niger and Trichoderma asperellum from the western Ghats of India,on coffee pulp,green tea,and a mixture of both substrates(50:50).T.asperellum(AFP)strain was found to have the highest growth rate(0.409±0.021 mm/h)using a mixture of both substrates.The production of cellulases by T.asperellum was unsatisfactory due to the presence of polyphenols in the supports to which A.nigger cellulases are more resistant.The production of cellulases by A.nigger was linked to the pH of the supports,favouring the use of T and TC.It was found that the extracts produced by A.niger(28A strain using a mixture substrate,28A,and 20A strains using only green tea as a substrate)presented the highest cellulase activities when evaluated using a plate technique producing degradation halos of 2.3±0.1 cm of diameter.Aspergillus 28A strain did not require mineral enrichment media for cellulase production using green tea residues as support of solid-state fermentation.

关键词： Cellulases Fungal strains Solid-state fermentation Agroindustrial wastes Coffee pulp Green tea

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