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The Journal of Biomedical Research 2020年第4期34卷 281-291页

作者： dimitri A.Svistunenko Andreea Manole Biomedical EPR Facility School ofLife SciencesUniversity of EssexColchesterEssex CO43SQUK Laboratory of Genetics The Salk Institute for Biological StudiesLa JollaCA 92037USA.

One of the difficulties in creating a blood substitute on the basis of human haemoglobin(Hb) is the toxic nature of Hb when it is outside the safe environment of the red blood *** plasma protein haptoglobin(Hp) takes care of the Hb physiologically leaked into the plasma-it binds Hb and makes it much less toxic while retaining the Hb’s high oxygen transporting *** used Electron Paramagnetic Resonance(EPR) spectroscopy to show that the protein bound radical induced by H2O2 in Hb and Hp-Hb complex is formed on the same tyrosine residue(s),but,in the complex,the radical is found in a more hydrophobic environment and decays slower than in unbound Hb,thus mitigating its oxidative *** data obtained in this study might set new directions in engineering blood substitutes for transfusion that would have the oxygen transporting efficiency typical of Hb,but which would be non-toxic.

关键词： blood substitute EPR haemoglobin toxicity haptoglobin HBOC protein-bound radical TRSSA

Spectral-Element andAdjointMethods in Seismology

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Communications in Computational Physics 2008年第1期3卷 1-32页

作者： Jeroen Tromp dimitri Komatitsch Qinya Liu Seismological Laboratory California Institute of TechnologyPasadenaCalifornia 91125USA. Department of Geophysical Modeling and Imaging University of Pau64013 Pau CedexFrance. Scripps Institution of Oceanography University of California San DiegoLa Jolla CA 92093-0225USA.

We provide an introduction to the use of the spectral-elementmethod (SEM)in seismology. Following a brief review of the basic equations that govern seismicwave propagation, we discuss in some detail how these equations may be solved numericallybased upon the SEM to address the forward problem in seismology. Examplesof synthetic seismograms calculated based upon the SEM are compared to datarecorded by the Global Seismographic Network. Finally, we discuss the challenge ofusing the remaining differences between the data and the synthetic seismograms toconstrain better Earth models and source descriptions. This leads naturally to adjointmethods, which provide a practical approach to this formidable computational challengeand enables seismologists to tackle the inverse problem.

关键词： Spectral-element method adjoint methods seismology inverse problems numerical simulations.

Iterative Bayesian Monte Carlo for nuclear data evaluation

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Nuclear Science and Techniques 2022年第4期33卷 105-135页

作者： Erwin Alhassan dimitri Rochman Alexander Vasiliev Mathieu Hursin Arjan JKoning Hakim Ferroukhi Laboratory for Reactor Physics and Thermal-Hydraulics Paul Scherrer Institute5232 VilligenSwitzerland Division Large Research Facilities(GFA) Paul Scherrer InstituteVilligenSwitzerland Ecole Polytechnique Federale de Lausanne LausanneSwitzerland Nuclear Data Section International Atomic Energy Commission(IAEA)ViennaAustria Division of Applied Nuclear Physics Department of Physics and AstronomyUppsala UniversityUppsalaSweden

In this work,we explore the use of an iterative Bayesian Monte Carlo(iBMC)method for nuclear data evaluation within a TALYS Evaluated Nuclear Data Library(TENDL)*** goal is to probe the model and parameter space of the TALYS code system to find the optimal model and parameter sets that reproduces selected experimental *** method involves the simultaneous variation of many nuclear reaction models as well as their parameters included in the TALYS ***‘best’model set with its parameter set was obtained by comparing model calculations with selected experimental *** experimental data types were used:(1)reaction cross sections,(2)residual production cross sections,and(3)the elastic angular *** improve our fit to experimental data,we update our‘best’parameter set—the file that maximizes the likelihood function—in an iterative *** was determined by monitoring the evolution of the maximum likelihood estimate(MLE)values and was considered reached when the relative change in the MLE for the last two iterations was within 5%.Once the final‘best’file is identified,we infer parameter uncertainties and covariance information to this file by varying model parameters around this *** this way,we ensured that the parameter distributions are centered on our *** proposed method was applied to the evaluation of p+^(59)Co between 1 and 100 ***,the adjusted files were compared with experimental data from the EXFOR database as well as with evaluations from the TENDL-2019,JENDL/He-2007 and JENDL-4.0/HE nuclear data libraries.

关键词： Iterative Bayesian Monte Carlo(iBMC) Nuclear reaction models Model parameters Adjustments Bayesian calibration Nuclear data TALYS

Metabolic activity of Streptococcus mutans biofilms and gene expression during exposure to xylitol and sucrose

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International Journal of Oral Science 2014年第4期6卷 195-204页

作者： Eva-Maria Decker Christian Klein dimitri Schwindt Christiane von Ohle Department for Pediatric and Operative Dentistry Periodontology and Endodontology Center of Dentistry Oral Medicine and Maxillofacial Surgery University of Tbingen Private Practice Zahngesundheit Waiblingen

The objective of the study was to analyse Streptococcus mutans biofilms grown under different dietary conditions by using multifaceted methodological approaches to gain deeper insight into the cariogenic impact of carbohydrates. S. mutans biofilms were generated during a period of 24 h in the following media： Schaedler broth as a control medium containing endogenous glucose, Schaedler broth with an additional 5% sucrose, and Schaedler broth supplemented with 1% xylitol. The confocal laser scanning microscopy（CLSM）-based analyses of the microbial vitality, respiratory activity（5-cyano-2,3-ditolyl tetrazolium chloride, CTC） and production of extracellular polysaccharides（EPS） were performed separately in the inner, middle and outer biofilm layers. In addition to the microbiological sample testing, the glucose/sucrose consumption of the biofilm bacteria was quantified, and the expression of glucosyltransferases and other biofilm-associated genes was investigated. Xylitol exposure did not inhibit the viability of S. mutans biofilms, as monitored by the following experimental parameters： culture growth, vitality, CTC activity and EPS production. However,xylitol exposure caused a difference in gene expression compared to the control. Gtf C was upregulated only in the presence of *** xylitol exposure, gtf B was upregulated by a factor of 6, while under sucrose exposure, it was upregulated by a factor of *** with glucose and xylitol, sucrose increased cell vitality in all biofilm layers. In all nutrient media, the intrinsic glucose was almost completely consumed by the cells of the S. mutans biofilm within 24 h. After 24 h of biofilm formation, the multiparametric measurements showed that xylitol in the presence of glucose caused predominantly genotypic differences but did not induce metabolic differences compared to the control. Thus, the availability of dietary carbohydrates in either a pure or combined form seems to affect the cariogenic potential of

关键词： biofilms 5-cyano-2 3-ditolyl tetrazolium chloride extracellular polysaccharides gene expression Streptococcus mutans sucrose viability xylitol

All journals should include a correspondence section

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World Journal of Gastroenterology 2022年第39期28卷 5731-5734页

作者： Nikolaos Papanas dimitri P Mikhailidis Debabrata Mukherjee Diabetes Centre Second Department of Internal MedicineDemocritus Univ ThraceAlexandroupolis 68100Greece Department of Surgical Biotechnology Division of Surgery and Interventional Scienceand Department of Clinical BiochemistryUniversity College London Medical SchoolRoyal Free Hosp CampusLondon NW32QGUnited Kingdom Department of Internal Medicine Texas Tech UniversityHealth Science CentralEl PasoTX 79905United States

Letters to the editor can provide useful scientific information and evaluation of published work as well as acting as an additional level of peer ***,letters are good reading material,especially if they involve a debate between ***,letters are relatively ***,inexperienced career researchers can use such an opportunity to practice putting together a cogent ***,it is far from an ideal situation if letters are the only(or main)type of article on which to base an academic career.

关键词： Correspondence Journals Letters to the editor Medical writing Peer review Debate

Feasibility of Using Wood Chips to Regulate Relative Humidity Inside a Building: A Numerical Study

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Journal of Renewable Materials 2019年第6期7卷 505-516页

作者： dimitri Bigot Cyril Ott Stéphane Guichard Bruno Malet-Damour University of La Réunion-40 avenue de Soweto-Terre Sainte-BP 373-97455 Saint-Pierre CedexLa RéunionFrance

The use of bio-based materials in buildings has become more and more significant last *** most of the cases,their health properties and natural provenance have made them a great solution to face global climate warming and the new policies to reduce building energy *** many thermal problems,biobased materials can allow to optimize the building thermal behavior according to its energy consumption and inside comfort *** it is when they are used as an insulation material in the ***,it is not the case in this *** fact,the bio-based matter is rather used as a desiccant wheel to control air conditioning inside the *** aim of this paper is to numerically verify if it is possible to use a bed of wood chips as a hygroscopic material(or a desiccant matter)in order to modify the relative humidity inside the building in Reunion Island and so improve thermal comfort.A simple model of heat and mass transfer between a bed of wood chips and building inside air has been set up and implemented into a validated building simulation code named *** simulations were set up for the four climate zones of the island regulations and a focus has been made on the low altitude one(with high,solar irradiation,temperature and relative humidity).Simulation results give the thermal behavior of the building particularly the temperature and relative humidity of inside air temperature,and temperature and moisture content of wood *** obtained results lead to determine if the wood chips bed is suitable for the reference building and to verify its technical feasibility(wood species,size of the bed,integration to the building,etc.).The results show that the use of a WCB help to decrease the building inside air temperature and water content up to 10°C less and 11.6 ***-1 *** are the ways to improve inside comfort ***,comfort analysis have shown the possibility to significantly increase building users’thermal comfort

关键词： Wood chips bed building inside comfort bio-based material desiccant relative humidity temperature building thermal modelling

Nanodiamonds as nanomaterial for biomedical field

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Frontiers of Materials Science 2021年第3期15卷 334-351页

作者： Sarah GARIFO dimitri STANICKI Gamze AYATA Robert NMULLER Sophie LAURENT General Organic and Biomedical Chemistry UnitNuclear Magnetic Resonance(NMR)and Molecular Imaging LaboratoryUniversity of Mons(UMONS)Avenue Maistriau 197000 MonsBelgium Center for Microscopy and Molecular Imaging(CMMI) Rue Adrienne Bolland 86041 GosseliesBelgium

Recent advances in nanotechnology have attracted significant attention to nanodiamonds(NDs)in both industrial and research areas thanks to their remarkable intrinsic properties:large specific area,poor cytotoxicity,chemical resistance,magnetic and optical properties,ease of large-scale production,and surface reactivity make them suitable for numerous applications,including electronics,optics,sensors,polishing materials,and more recently,biological *** interest in diamond platforms for bioimaging and chemotherapy is *** the outstanding features of these particles and their ease of tuning,current and future applications in medicine have the potential to display innovative imaging applications and to be used as tools for monitoring and tracking drug delivery in vivo.

关键词： nanodiamond scale-up synthesis bioimaging hyperpolarization drug delivery

Single Mutations in the Transmembrane Domains of Maize Plasma Membrane Aquaporins Affect the Activity of Monomers within a Heterotetramer

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Molecular Plant 2016年第7期9卷 986-1003页

作者： Marie C. Berny dimitri Gilis Marianne Rooman Francois Chaumont Institut des Sciences de la Vie University catholique de Louvain 1348 Louvain-la-Neuve Belgium Bioinformatique genomique et structurale Universite Libre de Bruxelles 1050 Brussels Belgium

Aquaporins are channels facilitating the diffusion of water and/or small uncharged solutes ecross biological membranes. They assemble as homotetramers but some of them also form heterotetramers, especially in plants. In Zea mays, aquaporins belonging to the plasma membrane intrinsic protein （PIP） subfamily are clustered into two groups, PIP1 and PIP2, which exhibit different water-channel activities when expressed in Xenopus oocytes. When PIP1 and PIP2 isoforms are co-expressed, they physically interact to modulate their subcellular localization and channel activity. Here, we demonstrated by affinity chromatography purification that, when co-expressed in Xenopus oocytes, the maize PIP1;2 and PIP2;5 isoforms assemble as homo- and heterodimers within heterotetramers. We built the 3D structure of such heterotetramers by comparative modeling on the basis of the spinach SoPIP2;1 X-ray structure and identified amino acid residues in the transmembrane domains which putatively interact at the interfaces between monomers. Their roles in the water-channel activity, subcellular localization, protein abundance, and physical interac- tion were investigated by mutagenesis. We highlighted single-residue substitutions that either inactivated PIP2;5 or activated PIP1;2 without affecting their interaction. Interestingly, the Phe220Ala mutation in the transmembrane domain 5 of PIP1 ;2 activated its water-channel activity and, at the same time, inactivated PIP2;5 within a heterotetramer. Altogether, these data contribute to a better understanding of the interaction mechanisms between PIP isoforms and the role of heterotetramerization on their water-channel activity.

关键词： aquaporin heterotetramer mutation oligomerization water-channel activity

Carrier frequency of HLA-DQB1*02 allele in patients affected with celiac disease:A systematic review assessing the potential rationale of a targeted allelic genotyping as a first-line screening

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World Journal of Gastroenterology 2020年第12期26卷 1365-1381页

作者： dimitri Poddighe Chiara Rebuffi Annalisa De Silvestri Cristina Capittini Department of Medicine School of MedicineNazarbayev UniversityNur-Sultan 010000Kazakhstan Grant Office and Scientific Documentation Center Fondazione IRCCS Policlinico San MatteoPavia 27100Italy Scientific Direction Clinical Epidemiology and Biometric UnitFondazione IRCCS Policlinico San MatteoPavia 27100Italy Department of Biology and Biotechnology"Lazzaro Spallanzani" University of PaviaPavia 27100Italy

BACKGROUND Celiac Disease(CD)is an immune-mediated disorder,in which the HLA immunogenetic background(DQ2 and DQ8 heterodimers)and environmental trigger(gluten)are well ***,both factors are necessary–but not sufficient–to develop ***,it is very likely that CD is underdiagnosed in both developing and developed countries,due to several aspects,including the fact that a lot of patients present mild and/or atypical symptoms,without the presence of any recognized risk ***,the possibility and feasibility of widened screening strategies to identify CD patients are *** To provide further evidence of the main epidemiological importance of HLADQB1*02 allele in the population of CD *** We performed a systematic search in PubMed,EMBASE,Cochrane,Web of Science and Scopus databases,in order to produce a systematic review assessing the carrier frequency of HLA-DQB1*02 allele in the celiac *** the PRISMA guidelines,we retrieved all the original articles describing CD patients’HLA-DQB1 genotype in such a way that could allow to assess the HLADQB1*02 carrier frequency among CD patients,along with the evidence of the appropriate diagnostic work-up to achieve a correct and final diagnosis of *** The final output of this systematic search in the medical literature consisted of 38 studies providing the appropriate HLA-DQB1 genotype information of the respective CD *** to this systematic review,including a pool of 4945 HLA-DQ genotyped CD patients,the HLA-DQB1*02 carrier frequency was 94.94%,meaning that only 5.06%of CD patients were completely lacking this allelic ***,if we consider only the studies whereby the prevalence of CD patients affected with type 1 diabetes mellitus was supposed or clearly established to be very low,the frequency of non-HLA-DQB1*02 carriers among CD patients dropped to 3.65%.CONCLUSION Such a high carrier frequency of the HLA-DQB1*02 allelic varian

关键词： Celiac disease Children HLA-DQB1*02 DQ2 heterodimer Screening Systematic review

A Systematic Design of Emulators for Multivariable Non Square and Nonlinear Systems

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International Journal of Automation and computing 2017年第6期14卷 742-754页

作者： Nesrine Bahri Asma Atig Ridha Ben Abdennour Fabrice Druaux dimitri Lefebvre University of Gabes National School of Engineers of Gabes-TunisiaStreet Omar Ibn Khattab 6029Gabes University of Havre 25 Rue Philippe Lebon76600 Le HavreFrance

In this paper, multimodel and neural emulators are proposed for uncoupled multivariable nonlinear plants with unknown dynamics. The contributions of this paper are to extend the emulators to multivariable non square systems and to propose a systematic method to compute the multimodel synthesis parameters. The effectiveness of the proposed emulators is shown through two simulation examples. The obtained results are very satisfactory, they illustrate the performance of both emulators and show the advantages of the multimodel emulator relatively to the neural one.

关键词： Uncoupled multimodel neural networks emulation multivariable nonlinear systems parameters estimation