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Journal of Earth Science 2024年

作者： flores daniel germán OCA?A Raúl Emmanuel MELIán Edgardo ORTEG Andrés ESPER AnGILLIERI María Yanina PITTALUGA María Alejandra CIGEOBIO (COnICET-UnSJ) Av.José I.de la Roza y Meglioli Gabinete de Geología Ambiental， InGEO， Universidad nacional de San Juan， Av.José I.de la Roza y Meglioli

The Monte Desert is characterized by a great diversity of landforms created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determine whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landforms， and 2: define whether morphometric， soil and surface properties influence vegetation patterns along alluvial landscape. Morphometric data were obtained by processing a 5 m digital elevation model. The coverage of rock fragments， fine sediments and mulch was quantified. Observations and descriptions of the soil profiles were restricted to the uppermost 50 cm. Vegetation properties were calculated using a Point Quadrat Method. The relationship between variables was evaluated through multivariate statistical analysis. The main results show the presence of 45 plant species distributed in 19 families， where shrubs are dominant. The wind effect， topographic wetness and dissection of the landscape are limiting factors of diversity. The coverage of superficial rock fragments influence vegetation coverage through the distribution and availability of rainwater. Furthermore， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and development of vegetation in the early stages of growth.

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Molecular Docking and Conceptual DFT-Based Study of Some Potential SARS-CoV-2 Inhibitors

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Computational Molecular Bioscience 2020年第4期10卷 111-128页

作者： norma flores-Holguín daniel Glossman-Mitnik Laboratorio Virtual nAnOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Miguel de Cervantes 120 Complejo Industrial Chihuahua Chihuahua Mexico

nowadays, the main effort of the scientific community is focused on the search of specific drugs for the inhibition of the Severe Acute Respiratory Syndrome—Coronavirus 2 (SARS-CoV-2), which is responsible for the Coro-navirus Disease 19 or COVID-19. With the same objective in mind, a Molecular Docking study was performed in this work in order to discover information about some antiviral drugs of common use as protease inhibitors. As a complement of this research, a chemical reactivity study of these potential drugs was done with the aim of finding a relationship between the inhibition ability and the chemical reactivity. The results presented in this research constitute one of the first predictions aimed to identify the best potential compounds for this purpose while at the same time verifying the validity of the employed theoretical and computational methodology. By means of the analysis of the number of hydrogen bonds as well as the binding energies coming from the Molecular Docking study, it can be said that Telaprevir, nelfinavir and Indinavir have the highest probability of success as potential inhibitors of SARS-CoV-2.

关键词： SARS-CoV-2 Molecular Docking DFT Binding Energy Conceptual DFT

Exploring the adjustment to parasite pressure hypothesis: differences in uropygial gland volume and haemosporidian infection in palearctic and neotropical birds

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Current Zoology 2021年第2期67卷 147-156页

作者： Sergio MAGALLAnES Anders Pape MøLLER Charlene LUJÁn-VEGA Esteban FOnG daniel VECCO Wendy flores-SAAVEDRA Luz GARCÍA-LOnGORIAA Florentino DE LOPE JoséA.IAnnACOnE Alfonso MARZAL Department of Anatomy Cellular Biology and ZoologyUniversity of ExtremaduraAvda.de Elvas S/NBadajoz ES-06006Spain Ecologie Systématique Evolution UniversitéParis-SudOrsay 91400France Key Laboratory for Biodiversity Science and Ecological Engineering of Ministry of Education College of Life SciencesBeiing Normal UniversityBeiing 100875China Pharmacology and Toxicology Graduate Group University of CaliforniaDavisDavisCA 95616USA EverGreen Institute-San Rafael Distrito de IndianaLoreto 16200Perú Centro Urku de Estudios Amazónicos Tarapoto 22202Perú Universidad nacional Agraria La Molina Lima 15024Perú Molecular Ecology and Evolution Lab Department of BiologyLund UniversityLund 22100Sweden Laboratorio de Ingenieria Ambiental Universidad Cientifica del Sur-Villa el SalvadorLima 15067Perú Laboratorio de Invertebrados Universidad Ricardo PalmaSantiago de Surco 15039Perú

Parasites are globally widespread pathogenic organisms,which impose im portant selective forces upon their ***,in accordance with the A djustm ent to parasite pressure hypothesis,it is expected that defenses among hosts vary relative to the selective pressure imposed by *** to the latitudinal gradient in diversity,species richness and abundance of parasites peak near the *** uropygial gland is an im portant defensive exocrine gland against pathogens in *** of the uropygial gland has been proposed to vary among species of birds because of divergent selection by pathogens on their ***,we should expect that bird species from the tropics should have relatively larger uropygial glands for their body size than species from higher ***,this hypothesis has not yet been ***,we analyze the size of the uropygial gland of 1719 individual birds belonging to 36 bird species from 3 neotropical(Peru)and 3 temperate areas(Spain).Relative uropygial gland volum e was 12.52%larger in bird species from the tropics than from temperate *** finding is consistent w ith the relative size of this defensive organ being driven by selective pressures imposed by *** also explored the potential role of this gland as a means of avoiding haemosporidian infection,showing that species with large uropygial glands for their body size tend to have lower mean prevalence of haemosporidian infection,regardless o f their geographical *** result provides additional support for the assum ption that secretions from the uropygial gland reduce the likelihood of becoming infected with haemosporidians.

关键词： adjustment to parasite pressure hypothesis malaria neotropical region preen oil temperate region

Computational Chemistry and Molecular Modeling Techniques for the Study of Micropeptin EI-964: Insights into Its Chemical Reactivity and Potential Pharmaceutical Properties

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Computational Molecular Bioscience 2023年第3期13卷 35-47页

作者： norma flores-Holguín Juan Frau daniel Glossman-Mitnik Laboratorio Virtual nAnOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Chihuahua Mexico Departament de Química Facultat de Ciències Universitat de les Illes Balears Palma de Mallorca Spain

Micropeptin EI-964 is a cyclic peptide compound isolated from a marine cyanobacterium with potent inhibitory activity against serine proteases, particularly chymotrypsin and trypsin. It has shown promising activity against various cancer cell lines, making it a candidate for drug development. The unique structure and activity of Micropeptin EI-964 make it a promising lead compound for the development of novel serine protease inhibitors and anti-cancer drugs. Computational Chemistry and Molecular Modeling techniques can provide valuable insights into the chemical reactivity and pharmaceutical properties of Micropeptin EI-964, guiding the design and development of new compounds with enhanced bioactivity and improved drug-like properties.

关键词： Micropeptin EI-964 Chemical Reactivity Conceptual DFT Computational Pharmacokinetics Pharmaceutical Drugs

Chemical Reactivity Properties, Drug-Likeness Features and Bioactivity Scores of the Cholecystokinin Peptide Hormone

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Computational Molecular Bioscience 2019年第2期9卷 41-47页

作者： norma flores-Holguín Juan Frau daniel Glossman-Mitnik Laboratorio Virtual nAnOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Chihuahua Mexico Departament de Química Universitat de les Illes Balears Palma de Mallorca Spain

Five density functionals, CAM-B3LYP, LC-ωPBE, Mn12SX, n12SX and ωB97XD, in connection with the Def2TZVP basis set were assessed together with the SMD solvation model for the calculation of the molecular and chemical reactivity properties of the Cholecystokinin peptide hormone (CCK-8) in the presence of water. All the chemical reactivity descriptors for the systems were calculated via Conceptual Density Functional Theory (CDFT). The potential bioavailability and druggability as well as the bioactivity scoresfor CCK-8 were predicted through different methodologies already reported in the literature which have been previously validated during the study of different peptidic systems. The conclusion was that the CCK-8 peptide will be moderately bioactive regarding all the interactions.

关键词： Cholecystokinin Peptide Hormone (CCK-8) Conceptual DFT Chemical Reactivity Drug-likeness Features Bioactivity Scores

Conceptual Density Functional Theory Study of the Chemical Reactivity Properties and Bioactivity Scores of the Leu-Enkephalin Opioid Peptide neurotransmitter

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Computational Molecular Bioscience 2019年第1期9卷 13-26页

作者： Juan Frau norma flores-Holguín daniel Glossman-Mitnik Departament de Química Universitat de les Illes Balears Palma de Mallorca Spain Laboratorio Virtual nAnOCOSMOS Departamento de Medio Ambiente y Energía Centro de Investigación en Materiales Avanzados Chihuahua Mexico

The SMD solvation model (Solvation Model based on the Density) and eight density functionals, CAM-B3LYP, LC-ωPBE, M11, Mn12SX, n12SX, ωB97, ωB97X, and ωB97XD, were assessed in link with the Def2TZVP basis set for the calculation of the structure of the Leu-Enkephalin Opioid Peptide neurotransmitter as well as their molecular properties. Through the Conceptual Density Functional Theory (CDFT), the entire chemical descriptors for the system were calculated. The active regions of the molecules necessary for electrophilic, nucleophilic and radical attacks were chosen through linking them with the corresponding Fukui functions. Furthermore, the prediction of the pKa value for the peptide is done with great accuracy as well as the ability of the studied molecule in acting as an efficient inhibitor of the formation of Advanced Glycation Endproducts (AGEs), which comprises of a useful knowledge for the development of drugs for preventing Alzheimer, Diabetes and Parkinson diseases. Lastly, the bioactivity scores for the studied peptides are predicted via various methodologies.

关键词： Leu-Enkephalin Opioid neurotransmitters Computational Chemistry Conceptual DFT Bioactivity Scores

Comparative study on simultaneous removal of calcium and sulfate ions from flotation recycling water by aluminum hydroxide

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Transactions of nonferrous Metals Society of China 2022年第7期32卷 2379-2390页

作者： Ángel daniel GUERRERO-flores Martha Araceli ELIZOnDO-ÁLVAREZ JoséManuel flores-ÁLVAREZ Alejandro URIBE-SALAS Department of Metallurgical Engineering CINVESTAV-IPNUnidad Saltillo25900Ramos ArizpeCoahuilaMéxico Department of Materials Unidad Académica de Ingeniería IUniversidad Autónoma de Zacatecas“Francisco García Salinas”ZacatecasZacatecasMéxico Facultad de Ciencias Químicas Universidad de ColimaCoquimatlánColimaMéxico

Due to the environmental policies and economic reasons,the water used in some flotation operations of complex sulfide ores is recirculated,causing the ion concentration of some species to increase over time,affecting the flotation of the minerals of *** this work,an experimental and thermodynamic analysis of the synthetic solutions was presented with a high content of calcium and sulfate *** study focused on evaluating the use of two aluminum compounds for the precipitation of Ca^(2+)and SO_(4)^(2−)in the form of *** amorphous aluminum hydroxide was found to be more efficient than the crystalline one,giving rise to 83%calcium and 91%sulfate *** XRD analysis of the solids showed the main reaction product of ettringite,accompanied by small amounts of calcite,due to the absorption of atmospheric carbon *** final solution after the chemical treatment showed residual calcium and sulfate concentrations below 200 mg/***,the kinetics of calcium removal appeared to correspond to a second order reaction with respect to calcium concentration,with an apparent activation energy of 53.48 kJ/mol,which may suggest that the ettringite precipitation process is governed by the chemical reaction.

关键词： ettringite ion removal aluminum hydroxide calcium sulfate

Computational Study of the Chemical Reactivity and Bioactivity Rates of Marine Peptides Hemiasterlin and Its A and B Derivatives Used in the Cancer Treatment through Conceptual Density Functional Theory

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Computational Molecular Bioscience 2019年第4期9卷 95-107页

作者： norma flores-Holguín Juan Frau daniel Glossman-Mitnik Laboratorio Virtual nAnOCOSMOS Departamento de Medio Ambiente y EnergíaCentro de Investigación en Materiales AvanzadosMiguel de Cervantes 120Complejo Industrial ChihuahuaChihuahua ChihMexico Departament de Química Universitat de les Illes BalearsPalma de MallorcaSpain

This study involved the assessment of the MnI2SX/Def2TZVP/H2O model chemistry to enhance the understanding of the structural composition of the marine peptide Hemiasterlin and its derivatives A and B used in cancer treatment. The Conceptual Density Functional theory was used in the calculation of molecular properties of the system chemical descriptors during the study. Integration of the active molecular regions into their respective Fukui functions was used in the selection of electrophilic and nucleophilic attacks. Additionally, the proposed correlation between global hardness and the pKa was used as the basis of deriving accurate predictions for the pKa values while a homology technique was used in the prediction of bioactivity and bioavailability scores of the peptides under investigation.

关键词： Hemiasterlins Computational Chemistry Conceptual DFT Bioavailability Bioactivity Scores

Chemical Reactivity Theory (CRT) Study of the Melanoidin M8: Local Conceptual Density Functional Theory Descriptors

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Computational Molecular Bioscience 2018年第2期8卷 80-90页

This study evaluated a fixed long-range corrected range-separated hybrid (RSH) density functional associated with the Def2TZVP basis set alongside the Solvation Model based on Density (SMD) for the computation of the structure, molecular properties and chemical reactivity of the M8 intermediate melanoidin pigment. The preference of the active sites pertinent to radical, nucleophilic and electrophilic attacks is made through linking them with the electrophilic and nucleophilic Parr functions, Fukui function indices, and condensed Dual Descriptor. This study showed that the Mn12SX density functional is the most suitable one for predicting the chemical reactivity of this system.

关键词： Melanoidin M8 Conceptual DFT Chemical Reactivity Dual Descriptor Parr Function

numerical Analysis of Slag Carry-Over during Molten Steel Draining

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Open Journal of Applied Sciences 2017年第11期7卷 611-616页

作者： daniel flores-Sanchez Miguel A. Barron Departmento De Materiales Universidad Autonoma Metropolitana Mexico City Mexico

Slag carry-over during the draining of molten steel from a teeming ladle is numerically studied here. Two-phase isothermal transient 3D Computational Fluid Dynamics simulations were employed to simulate the draining process. Two nozzle diameters, two nozzle positions and three slag heights were considered. From mass balances, the slag carry-over in terms of mass flow rate was obtained for each of the above variables. Besides, the draining times of the teeming ladle were estimated from theoretical considerations and CDF simulations, and compared.

关键词： CFD Simulations Draining Time Multiphase Flow Slag Carry-Over Teeming Ladle