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Impact of data balancing a multiclass dataset before the creation of association rules to study bacterial vaginosis

智慧医学（英文） 2024年第3期04卷 188-199页

作者： de la cruz-ruiz freddy Canul-Reich Juana Rivera-López Rafael de la cruz-Hernández Erick Academic Division of Science and Technology of the Information Juárez Autonomous University of Tabasco La Esmeralda District Tabasco Mexico department of Systems National Technological Institute of Mexico Technological Institute of Veracruz Veracruz Mexico Multidisciplinary Academic Division of Comalcalco Juárez Autonomous University of Tabasco Tabasco Mexico

Background:Bacterial vaginosis is a polymicrobial syndrome in which the homeostasis exerted by the latobacillus species that protect the vaginal mucosa has been lost. This study explored the data balancing process with the intention of improving the quality of association rules. The article aimed to balance the unbalanced multiclass dataset to improve association rule creation. Methods:A dataset with 201 observations and 58 variables was analyzed. A preconstructed dataset was used. The authors collected the data between August 2016 and October 2018 in Tabasco, Mexico. The study population comprised sexually active women ages 18 to 50 who underwent gynecological inspection at the infectious and metabolic diseases research laboratory at the Universidad Juarez Autonoma de Tabasco. To determine the best k-value, the random-forest algorithm was used and the balancing was performed with the synthetic minority over-sampling technique (SMOTE), random over-sampling examples (ROSE), and adaptive syntetic sampling approach for imbalanced learning (ADASYN) algorithms. The Apriori algorithm created the rules and to select rules with statistical significance, the ***(), ***(), and ***() functions and quality metric Fisher’s exact tes were used. The biological validation was carried out by the expert (bacteriologist). Results:The ADASYN algorithm at K = 9 the out of the bag (OOB) error was zero, this was the best K-values. In the balancing process the ADASYN algorithm show best the performance. From the dataset balanced with ADASYN, the apriori algorithm created the association rules and the selection with the quality metric Fisher’s exact test, and the biological validation reported 13 rules. Gram - bacteria Atopobium vaginae, Gardnerella vaginalis, Megasphaera filotipo 1,Mycoplasma hominis and Ureaplasma parvum were detected by the apriori algorithm from the balanced dataset. Conclu

关键词： Bacterial vaginosis Data balancing Random forest Synthetic minority over-sampling technique

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Role of bioengineering structures made of willow cuttings in marly sediment trapping: assessment of three real-size experiments in the Southern French Alps

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Journal of Mountain Science 2018年第2期15卷 225-236页

作者： freddy REY Univ.Grenoble Alpes Irstea Grenoble

Improving knowledge on the ability of bioengineering structures made of willow cuttings to enhance efficient and sustainable sediment trapping in marly gullies in the Southern French Alps under a mountainous Mediterranean climate, to decreasesediment trapped per experiment, the mean annual values reached 0.25, 0.14 and 0.08 m3 yr-1 in experiments C, A and B, respectively. Maximum values for one structure reached 1.94 m3 per year in experiment C. The significance of the volumes ofsediment yield at their outlets, is a key issue today for the international scientific community working in geosciences and ecology. This study therefore aims to assess three real-size experiments(A, B and C) carried out between 2003 and 2013 in this environment. A total of 157 bioengineering structures using purple and white willow(Salix purpurea and Salix incana)cuttings – which have been shown to resprout and survive more than 2 years after their installation,corresponding to brush layers with brush mats on wooden sills(BLM), 1.2 m wide and 2 m long,installed on the floors of 33 experimental marly gullies, were monitored. The results showed that sediment trapping occurred upstream of the vegetation barriers from the 1 st year *** the depth of sediment trapped per experiment, the mean annual values reached 11.2 cm yr-1 after 3 years in experiment A, 7.7 cm yr-1 after 2–4 years in experiment C and 5.1 cm yr-1 after 5 years in experiment B. Occasionally, BLMs showed that they could trap up to 16 and 15 cm yr-1 in experiments A and C, respectively. Considering the volumes oftrapped sediment and the sustainability of sediment trapping are discussed, and rules for bioengineering strategies are proposed.

关键词： Erosion Marly gully Vegetation barriers Ecological engineering Salix

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Inductive effect of Ti-doping in Fe_(2)O_(3)enhances the photoelectrochemical water oxidation

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Science China Chemistry 2023年第7期66卷 2091-2097页

作者： Yumei Lin Yan Wang Hongxia Wang Jingjing Wang Xiaofeng Wu Jan P.Hofmann Giulio Gorni Victor A.de la Pena O'Shea freddy E.Oropeza Kelvin H.L.Zhang State Key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Surface Science laboratory Department of Materials and Earth SciencesTechnical University of DarmstadtDarmstadt 64287Germany CELLS-ALBA Synchrotron Barcelona 08290Spain Institute of Optics(IO-CSIC) c/Serrano 121Madrid 28006Spain Photoactivated Processes Unit IMDEA Energy InstituteMadrid 28935Spain

Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water *** of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research efforts,the underlying mechanism still remains *** this work,we report a comprehensive study on the relationship between the electronic structure,interfacial reaction kinetics and PEC activity of Ti-doped Fe_(2)O_(3)*** results show that the interfacial charge transfer efficiency at the Fe_(2)O_(3)/electrolyte interface is the main factor in the significant increase of the PEC activity of doped Fe_(2)O_(3).Electrochemical impedance spectroscopy reveals that the interfacial charge transfer efficiency is determined by energy overlap between the water oxidation potential and energy distribution of an intermediate surface state that has been identified as Fe^(IV)=O groups on Fe_(2)O_(3)surface generated during PEC ***,the potential energy distribution of this intermediate surface state can be modulated by Ti doping,and a shift towards a more positive potential of the intermediate surface state increases the overlap with the water oxidation potential and thus enhances the kinetics of charge transfer for PEC water *** origin of such potential energy modulation is traced to the inductive effect from Ti-doping on the Fe^(3+)/Fe^(4+)redox transition and the Fe-O bond *** results provide new insight into the mechanism for the doping effect on the PEC water splitting,introducing new strategies to optimize the PEC activity by tuning the redox properties of active metal oxides.

关键词： hematite surface states doping photoelectrochemical water splitting electronic structure

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Highly efficient multi-metal catalysts for carbon dioxide reduction prepared from atomically sequenced metal organic frameworks

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Nano Research 2021年第2期14卷 493-500页

作者： Celia Castillo-Blas Consuelo Alvarez-Galvan Ines Puente-Orench Alba Garcia-Sanchez freddy E.Oropeza Enrique Gutirrez-Puebla Angeles Monge Victor A.de la Pena-O'hea Felipe Gandara Materials Science Institute of Madrid(CSIC) C/Sor Juana Ines de la Cruz 3Madrid 28049Spain Instituto de Catalisis y Petroleoquimica(CSIC) dM arie Curie 2Madrid 28049Spain Instituto de Ciencia de Materiales de Aragon Pedro Cerbuna 12Zaragoza 50009Spain Institut laue langevin 71 Avenue des Martyrs38042 GrenobleFrance Photoactivated Processes Unit IMdeA Energy Institute Mostoles Technology ParkAvenida Ramdn de la Sagra 3MostolesMadrid 28935Spain department of Inorganic Chemistry University Autonomous of MadridC/Frandsco Tomdsy Valiente 7Madrid 28049Spain

The precise control on the combination of multiple metal atoms in the structure of metal-organic frameworks(MOFs)endowed by reticular chemistry,allows the obtaining of materials with compositions that are programmed for achieving enhanced *** present work illustrates how through the transformation of MOFs with desired arrangements of metal cations,multi-metal spinel oxides with precise compositions can be obtained,and used as catalyst precursor for the reverse water-gas shift *** differences in the spinel initial composition and structure,determined by neutron powder diffraction,influence the overall catalytic activity with changes in the process of in s itu formation of active,metal-oxide supported metal nanoparticles,which have been monitored and characterized with in situ X-ray diffraction and photoelectron spectroscopy studies.

关键词： reticular chemistry multi-metal metal-organic frameworks(MOFs) carbon dioxide reduction heterogeneous catalysis reverse water-gas shift in-situ X-ray photoelectron spectroscopy(XPS)

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Correlating the electronic structure of perovskite la_(1-x)SrxCoO_(3) with activity for the oxygen evolution reaction:The critical role of Co 3d hole state

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Journal of Energy Chemistry 2022年第2期31卷 637-645页

作者： Zechao Shen Mei Qu Jueli Shi freddy E.Oropeza Victor A.de la Peña O’Shea Giulio Gorni C.M.Tian Jan P.Hofmann Jun Cheng Jun Li Kelvin H.L.Zhang State Key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Photoactivated Processes Unit IMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain CELLS-ALBA Synchrotron Carrer de la Llum 2-2608290 Cerdanyola del VallèsSpain Surface Science laboratory Department of Materials and Earth SciencesTechnical University of Darmstadt Otto-Berndt-Strasse 364287 DarmstadtGermany

Perovskite laCoO_(3) is being increasingly explored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).Sr doping in laCoO_(3)(la1-xSrxCoO_(3))has been found to substantially increase its catalytic *** this work,we report a detailed study on the evolution of the electronic structure of la1-xSrxCoO_(3) with 0≤x≤1 and its correlation with electrocatalytic activity for the OER.A combination of X-ray photoemission spectroscopy(XPS)and X-ray absorption spectroscopy(XAS)was used to unravel the electronic density of states(DOS)near the Fermi level(EF),which provide insights into the key electronic structure features for the enhanced OER catalytic *** analysis on the Co L-edge XAS suggest that laCoO_(3) has a low spin state with t_(2g)^(6) e_(g)^(0) configuration at room *** implies that the high OER catalytic activity of laCoO_(3) should not be rationalized by the occupancy of eg=1 *** Sr^(2+) for la^(3+) in laCoO_(3) induces Co4+oxidation states and effectively dopes hole states into the top of valence band.A semiconductor-to-metal transition is observed for x>0.2,due to the holeinduced electronic DOS at the EF and increased hybridization between Co 3 d and O 2 *** an electronic modulation enhances the surface adsorption of the*OH intermediate and reduces the energy barrier for interfacial charge transfer,thus improving the OER catalytic activity in la_(1-x)Sr_(x)CoO_(3).In addition,we found that the la_(1-x)Sr_(x)CoO_(3) surface undergoes amorphization after certain period of OER measurement,leading to a partial deactivation of the *** Sr doping levels accelerated the amorphization process.

关键词： Perovskite oxide Oxygen evolution Cobalt Electronic structure

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Vertically aligned Ni/NiO nanocomposites with abundant oxygen deficient hetero-interfaces for enhanced overall water splitting

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Science China Chemistry 2022年第10期65卷 1885-1894页

作者： Hongxia Wang Meiyan Cui Gaoliang Fu Jiaye Zhang Xingyu Ding Irene Azaceta Matthew Bugnet demie M.Kepaptsoglou Vlado K.lazarov Victor Ade la Peña O’Shea freddy E.Oropeza Kelvin H.L.Zhang State Key laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Henan Provincial Key laboratory of Nanocomposites and Applications Institute of Nanostructured Functional MaterialsHuanghe Science and Technology CollegeZhengzhou 450006China department of Physics University of YorkHeslingtonYorkYO105DDUK SuperSTEM laboratory SciTech Daresbury CampusDaresbury WA44ADUK School of Chemical and Process Engineering Univeristy of LeedsLeeds LS29JTUK Univ Lyon CNRSINSA LyonUCBLMATEISUMR 551069621 VilleurbanneFrance Photoactivated Processes Unit IMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain

The design of heterostructured transition metal-based electrocatalysts with controlled composition and interfaces is key to increasing the efficiency of the water electrolysis and the elucidation of reaction *** this work,we report the synthesis of well-controlled vertically aligned Ni/NiO nanocomposites consisting of Ni nanoclusters embedded in NiO,which result in highly efficient electrocatalysts for overall water *** show that such a high catalytic efficiency toward both the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)originates from a synergetic effect at Ni/NiO interfaces that significantly reduces the energy barrier for water dissociation,and favours the formation of reactive H*intermediates on the Ni side of the interface,and OH_(ads) on the NiO side of the interface.A study of water chemisorption based on near-ambient pressure photoelectron spectroscopy indicates that the abundant hetero-interfaces in Ni/NiO nanocomposite promote the dissociation of water with a three-fold increase in the surface concentration of OH_(ads) compared with pure *** functional theory calculations indicate that Ni/NiO interface leads to the reduction of the water dissociation energy barrier due to a high concentration of oxygen vacancies at NiO side of the interface,whereas the formation of highly active metallic Ni sites with an optimal value of Gibbs free energy of H*(ΔG_(H*)=−0.16 eV)owes to a favourable adjustment of the electron energetics at the interface,thus accelerating the overall electrochemical water splitting.

关键词： water splitting hydrogen evolution reaction electronic structure heterostructure vertically aligned nanocomposites

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Pore structure effects on the kinetics of methanol oxidation over nanocast mesoporous perovskites

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Chinese Journal of Catalysis 2016年第1期37卷 32-42页

作者： Mahesh M.Nair freddy Kleitz Serge Kaliaguine 拉瓦尔大学化学Materiaux Avances研究中心(CERMA) 加拿大魁北克G1V 0A6 拉瓦尔大学化工系加拿大魁北克G1V 0A6

Mesoporous laMnO3 perovskite catalysts with high surface area were synthesized by using the recently developed hard templating method designated as ＂nanocasting＂.Ordered mesoporous silica designated as SBA-15 was used as the hard *** was found that the surface area of the nanocast perovskites can be tuned（80–190 m2/g）by varying the aging temperature of the SBA-15 *** laMnO3 catalysts showed high conversion efficiencies for the total oxidation of methanol under steady state conditions,the one with the highest value of surface area being the best catalysts,as *** studies were performed for all of the synthesized *** constants were found to vary in accordance with the specific surface area of the nanocast catalyst which depends on the aging temperature of the parent *** the rate constants obtained from experimental conversions at various space velocities（19500 to 78200 h〈sup〉–1）,values of activation energy and pre-exponential factor for the three nanocast laMnO3 catalysts were determined by the linear regression of the Arrhenius *** is observed that the activation energy for all the catalysts remain constant irrespective of the variation in specific surface ***,a linear relationship was found to exist between the pre-exponential factor and specific surface areas of the catalysts indicating that the rates per unit surface area remains the same for all the catalysts.

关键词： Mesoporous perovskites High surface area Nanocasting Methanol oxidation Kinetics

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Synthesis, characterization and biological applications of novel Schiff bases of 2-(trifluoromethoxy) aniline

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Journal of Chinese Pharmaceutical Sciences 2018年第5期27卷 307-323页

作者： Thierry Youmbi Fonkui Monisola Itohan Ikhile freddy Munyololo Muganza Marthe Carine Djuidje Fotsing Charmaine Arderne Xavier Siwe-Noundou Rui Werner Macedo Krause derek Tantoh Ndinteh Patrick Berka Njobeh department of Biotechnology and Food Technology University of Johannesburg department of Applied Chemistry University of Johannesburg department of Chemistry Sefako Makgatho Health Sciences University department of Chemistry University of Johannesburg department of Chemistry Rhodes University

A series of five new Schiff bases(1–5) were synthesized by reacting 2-(trifluoromethoxy) aniline with different aromatic aldehydes. The Schiff base compounds were characterized by spectroscopic and analytical methods. Crystal structure of one new compound was also reported. The pharmacological properties, including antibacterial(14 bacterial species), antifungal(7 strains), antimalarial, anti-trypanosomal and anti-HIV activities of the compounds, were investigated. Cytotoxicity of the tested compounds was evaluated against human cervix adernocarcinoma cells(He la). Bacterial minimum inhibitory concentration(MIC) results by broth microdilution method showed that Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Proteus vulgaris, Klebsiella oxytoc and Klebsiella pneumonia were more sensitive in the presence of tested compounds with an MIC value of 15.6 μg/m L. All the tested compounds showed good to moderate activity against fungi. The sensitivity of Aspergillus fumigatus was higher than other strains with a minimum cell death concentration(MFC) of 15.6 μg/m L. Compound 1 showed greater antimalarial and anti-trypanosomal properties with very low to no cytotoxic effects against He la cells as compared with compound 5, while other compounds exhibited poor activity. Compounds 1–5 demonstrated good activity against HIV type-1. These Schiff base compounds could be used as good antimicrobial agents.

关键词： Synthesis Biological activity Schiff bases Antimicrobial 2-(Trifluoromethoxy) aniline

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Neutralization of Omicron BA.1,BA.5.1.6,BQ.1.3 and XBB1.1 induced by heterologous vaccination Ad5-nCoV and mRNA-1273

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Signal Transduction and Targeted Therapy 2023年第5期8卷 2085-2087页

作者： Jesús Hernández freddy dehesa-Canseco Alma B.Vázquez-López Mónica Reséndiz-Sandoval Graciela Caire-Juvera Mario Solís-Hernández Olivia Valenzuela Bruno Gómez-Gil Verónica Mata-Haro Centro de Investigación en Alimentación y desarrollo A.C.HermosilloSonora83304Mexico Comisión México-Estados Unidos para la Prevención de la Fiebre Aftosa y otras Enfermedades Exóticas de los Animales(CPA) SENASICASADERCiudad de México05010Mexico departamento de Ciencias Químico Biológicas Universidad de SonoraHermosilloSonora83000Mexico

dear Editor,The emergence of Omicron subvariants has required additional boosters to induce a highly neutralizing antibody response.1 However,the new Omicron subvariants BQ.1 and XBB,evade the humoral response induced by multiple mRNA vaccinations and infections.2,3 CansinoBio(Ad5-nCoV)is a single-dose adenovirus vector-based vaccine with high protection against severe disease4 but lower efficacy and antibody response than mRNA ***,hybrid immunity induced by infection plus vaccine or heterologous vaccines has produced a robust neutralizing antibody response.

关键词： vaccination vaccine immunity

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Anti-Inflammatory and Analgesic Effects of Aqueous Extract of Stem Bark of <i>Ceiba pentandra</i>Gaertn

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Pharmacology & Pharmacy 2014年第12期5卷 1113-1118页

作者： Romaric de Garde Elion Itou Rokia Sanogo Arnaud Wilfrid Etou Ossibi freddy Gelase Nsondé Ntandou Radard Ondelé Bonaventure Max Pénemé Nadége Okiémy Andissa Drissa Diallo Jean Maurille Ouamba Ange Antoine Abena laboratoire de Biochimie et Pharmacologie Faculté des Sciences de la Santé Université Marien Ngouabi Brazzaville Congo Département Médecine Traditionnelle (DMT) Faculté de Médecine de Pharmacie et d’Odonto-StomatologieUniversité de Bamako Bamako Mali Unité de Chimie du Végétale et de la vie Faculté des Sciences et Techniques Université Marien Ngouabi Brazzaville Congo

Anti-inflammatory and analgesic effects of the aqueous extract of the stem bark of Ceiba pentandra Gaertn (Bombacaceae) were recorded in rat and mice. Inflammation was induced by carrageenan and cotton pellet. The pain was studied using analgesymeter, Koster and hot plate Methods. Aqueous extract (400 and 800 mg/kg) of Ceiba pentandra presents a significant anti-inflammatory and analgesic activity. Flavono?ds present in the extract seem to be responsible for the activity.

关键词： Analgesic Anti-Inflammatory Ceiba pentandra

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