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Expanding the Boundaries of the Chemical space of DNA Methyltransferase 1 Modulators

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Computational Molecular Bioscience 2024年第1期14卷 1-16页

作者： Massyel s. Martínez-Cortés Diana l. Prado-Romero José l. medina-Franco DIFACQUIM Research Group Department of Pharmacy School of Chemistry Universidad Nacional Autónoma de México Avenida Universidad 3000 Mexico City México

DNA methyltransferase 1 (DNMT1), one of the main epigenetic targets, is involved in the duplication of the DNA methylation pattern during replication, and it is essential for proper mammalian development. small molecule DNMT1 modulators are attractive for biochemical epigenetic studies and have the potential to become drugs. so far, more than five hundred small molecules have been reported as DNMT1 inhibitors. However, only a limited number of DNMT1 activators have been disclosed because, at least in part, DNMT1 activators are typically regarded as negative data in virtual screening campaigns or optimization projects. This manuscript aims to report the chemical structures and biological activity of small molecules that increase the enzymatic activity of DNMT1. Results of the biochemical experimental assays are discussed. It was found that small molecule activators have a large variety of chemical scaffolds but share pharmacophore features. Visual analysis of the chemical space and multiverse based on molecular fingertips supported that activators are structurally diverse. This is the first report of eight small molecules that increase the enzymatic activity of DNMT1 by more than 400% in an enzymatic-based assay. The outcome warrants further investigation of the epigenetic activity of the compounds in a counter-screen assay, e.g., cell-based and in vivo context.

关键词： Chemical Multiverse Chemoinformatics Epigenetics Pharmacophore Hypothesis small Molecules

solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHPA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： P.A.Martínez-Montoya R.G.sanchez-Alvarado D.Y.medina-Velazquez M.l.Carrera-Jota P.Garnica-Chávez A.de J.Morales-Ramirez Higher school of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/l Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(s/l)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHPA functionalized resin,pH=1.5 and an s/l ratio of 10 mg/ml The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/l [H_(2)sO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)sO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery Rare earth solid-liquid extraction XAD-7 resin Fluorescent lamps recycling solid-liquid kinetics extraction

Autoantibodies against beta cells to predict early insulin requirements in pediatric patients with clinically diagnosed type 2 diabetes

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World Journal of Diabetes 2024年第8期15卷 1717-1725页

作者： Jorge M Molina Patricia G medina Rita A Gomez Julia R Herrera Nancy l Martínez Brenda Hernández Yesenia García Department of Endocrinology Children’s Hospital Federico GomezMexico 06720Mexico National Medical Center"siglo XXI" UMAE Hosp EspecialidadesUnidad Invest Med Epidemiol ClinMexican Social Security InstituteMexico 06720Mexico Research Division UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIMexican Institute of Social SecurityMexico 06720Mexico Epidemiology Research Unit in Endocrinology and Nutrition Federico Gómez Children’s HospitalMexico 06720Mexico Department of Endocrinology Comprehensive Health Unit for Trans PersonsMexico 11340Mexico

BACKGROUND Autoimmunity has emerged as a probable disease modifier in patients with clinically diagnosed type 2 diabetes mellitus(T2DM),that is,patients who have insulin resistance,obesity,and other cardiovascular risk factors,suggesting that the presence of glutamic acid decarboxylase(anti-GAD65),islet antigen 2(anti-IA2),and zinc transporter 8(anti-Zn8T)antibodies could have deleterious effects on beta cell function,causing failure and earlier requirement for insulin *** To evaluate anti-GAD65,anti-IA2 and anti-Zn8T as predictors of early insulin requirement in adolescents with a clinical diagnosis of *** This was a case–control study in patients with clinically diagnosed with T2DM(68 cases and 64 controls with and without early insulin dependence respectively),male and female,aged 12–18 ***,blood pressure,glucose,insulin,C-peptide,glycated hemoglobin A1c,and lipid profiles were *** was used to measure anti-GAD65,anti-IA2,and anti-Zn8T *** statistics,Pearson'sχ2 test,student's t test,and logistic regression was performed.Ps considered statistically *** There were 132 patients(53.8%female),with a mean age was 15.9±1.3 years,and there was a disease evolution time of 4.49±0.88 *** presence of anti-GAD65,anti-IA2,and anti-Zn8T positivity was found in 29.5%,18.2%,and 15.9%,*** the groups by early or no insulin dependence showed that the group with insulin had a higher frequency of antibody positivity:anti-GAD65 odds ratio(OR):2.42(1.112–5.303,P=0.026);anti-IA2:OR:1.55(0.859–2.818,P=0.105);and anti-Zn8T:OR:7.32(2.039–26.279,P=0.002).CONClUsION Anti-GAD65 positivity was high in our ***-GAD65 and anti-Zn8T positivity showed a significantly depleted beta cell reserve phenotype,leading to an increased risk of early insulin dependence.

关键词： Diabetes Obesity Adolescents Autoimmunity Beta cell Insulin requirements

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l silva l.A.O.Nunes s.M.lima l.H.C.Andrade Optical and Photothermal spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Weighted Probability Density Estimator with Updated Bandwidths

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Journal of systems science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKAsA RAO B l s school of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China school of Big Data and statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild ***,the random weighted estimator is also *** numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Model dependent analysis of D^(+)_(s)→η^(′)l+v_(l) decays in beyond standard model

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Chinese Physics C 2024年第9期48卷 82-95页

作者： s.Mahata M.Mandal H.Mahapatra s.Biswas s.sahoo Department of Physics National Institute of Technology Durgapur Durgapur 713209West BengalIndia

Motivated by the recent experimental results of branching fractions for D^(+)_(s)→η^(′)l+v_(l) decays,which deviate from their sM predictions,we hve investigated these decays in W' model and scalar leptoquark model to determine potential signatures of new physics(NP) in semileptonic charm decays induced by c→(s,d)l+v_(l) *** recent experimental results of branching fractions for semileptonic D meson decays,new coupling parameters are predicted for the aforementioned NP *** fraction,forward-backward asymmetry,and lepton polarization asymmetry are examined by considering the predicted NP coupling *** results of branching fractions in scalar leptoquark model are found very close to the experimental results and exist around the range of 1σ *** presented a comparative study of the NP models to check their sensitivity on these *** anticipate that further research on these decays will significantly support our findings.

关键词： charm decay new physics W′boson scalar leptoquark flavour changing charged current

Model Change Active learning in Graph-Based semi-supervised learning

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1270-1298页

作者： Kevin s.Miller Andrea l.Bertozzi Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLos AngelesCA 90095USA

Active learning in semi-supervised classification involves introducing additional labels for unlabelled data to improve the accuracy of the underlying classifier.A challenge is to identify which points to label to best improve performance while limiting the number of new labels."Model Change"active learning quantifies the resulting change incurred in the classifier by introducing the additional label(s).We pair this idea with graph-based semi-supervised learning(ssl)methods,that use the spectrum of the graph laplacian matrix,which can be truncated to avoid prohibitively large computational and storage *** consider a family of convex loss functions for which the acquisition function can be efficiently approximated using the laplace approximation of the posterior *** show a variety of multiclass examples that illustrate improved performance over prior state-of-art.

关键词： Active learning Graph-based methods semi-supervised learning(ssl) Graph laplacian

Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： silvana Trindade luiz F.Bittencourt Nelson l.s.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning