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electrochemical Analysis of Zirconiumin Aqueous and Organic Media

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American Journal of Analytical Chemistry 2024年第2期15卷 99-118页

作者： Paul Mendy Démo Koita theodore Tzedakis Cheikhou Kane Codou Guèye Mar-Diop ecole Supérieure Polytechnique Université Cheikh Anta DIOP Dakar Sénégal Laboratoire de Génie Chimique Université de Toulouse III—Paul Sabatier Toulouse France

For the challenging nature of the zirconium environment analysis, this study consists to analyze the electrochemical behavior of Zirconium in both aqueous and organic media. To that end first the electrolytic media was selected on the basis of the Pourbaix potential-pH diagram, which provides informations on the predominance of Zr(IV) ion and Zr in aqueous media. In aqueous media, analyzes were first carried out in acidic media then in basic media. Studies have thus revealed that the acidic environment is not favourable for the electrochemical analysis of zirconium. Voltammograms obtained in an acidic environment show no zirconium detection signal;this is due to the strong presence of H+ ions in the solution. We have also observed in acidic media the phenomenon of passivation of the electrode surface. In aqueous alkaline media (pH = 13), we have drawn in reduction several Intensity-Potential curves by fixingsome technical parameterslike scanning speed, rotation speed of the electrode. The obtained voltammograms show cathodic waves, starting from -1.5 V/DHW and attributed to the reduction of Zr (IV) to Zr (0). The last phase of this study focused on the electrochemical analysis of zirconium in an organic media. In this media, several intensity-potential curves were plotted in reduction and in cyclic voltammetry with various parameters. Through several reduction analysis, the Zr (IV) was reduced to Zr (0) to the potential of -1.5 V/DHW. The electrochemical analysis of zirconium in organic media seems globally easier to achieve thanks to its large solvent window (i.e. dimethylformamide (DMF) solvent window > 6 V).

关键词： Zirconium electrochemical Reduction Cyclic Voltammetry Voltammogram Dymethylformamide

Systems and Control Impact in a Changing World

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维普期刊数据库

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Individual differences in transcranial electrical stimulation current density

第二十六届中国控制会议

作者： Djaferis theodore e electrical and Computer engineering University of Massachusetts Amherst

ISBN: (纸本)7900719229;9787900719225

The later half of the twentieth century can be characterized as a golden age for systems and control.A tremendous research effort led to the discovery of new knowledge that had a dramatic impact on the solution of many challenging engineering *** now face a new century and a new set of engineering problems many that lie at the boundaries of established *** the same time many technological innovations are constantly changing the *** creates challenges as well as opportunities for systems and control *** new century and global realities also create a new set of issues for engineering *** the educational arena many questions are being raised as to how engineering education should be shaped in both structure and content to better address the needs of the 21st *** course research and education are inextricably connected as past research developments shape the current engineering educational system and educational systems are in many ways crafted to facilitate *** is a fact that systems and control educators have historically played a fundamental role in engineering education and we are now poised to take a leadership role in shaping it for the future.I believe that the systems and control community has an opportunity to have a much greater impact on research and education in the 21st *** this talk I discuss these issues from my personal perspective drawing from my experiences over the last thirty years.

关键词： systems and control research systems and control education

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cnki会议

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The Journal of Biomedical Research 2013年第6期27卷 495-508页

作者： Michael J Russell theodore Goodman Ronald Pierson Shane Shepherd Qiang Wang Bennett Groshong David F wiley Aaken Research Institute Inc. Sutter Center for Psychiatry Brain Image Analysis LLC Radiological Associates of Sacramento Inc. Stratovan Corp.

Transcranial electrical stimulation （TCeS） is effective in treating many conditions, but it has not been possible to accurately forecast current density within the complex anatomy of a given subject＇s head. We sought to predict and verify TCeS current densities and determine the variability of these current distributions in patient-specific models based on magnetic resonance imaging （MRI） data. Two experiments were performed. The first experiment estimated conductivity from MRIs and compared the current density results against actual measurements from the scalp surface of 3 subjects. In the second experiment, virtual electrodes were placed on the scalps of 18 subjects to model simulated current densities with 2 mA of virtually applied stimulation. This procedure was repeated for 4 electrode locations. Current densities were then calculated for 75 brain regions. Comparison of modeled and measured external current in experiment 1 yielded a correlation of r = .93. In experiment 2, modeled individual differences were greatest near the electrodes （ten-fold differences were common）, but simulated current was found in all regions of the brain. Sites that were distant from the electrodes （e.g. hypothalamus） typically showed two- fold individual differences. MRI-based modeling can effectively predict current densities in individual brains. Significant variation occurs between subjects with the same applied electrode configuration. Individualized MRI- based modeling should be considered in place of the 10-20 system when accurate TCeS is needed.

关键词： RI modeling current density transcranial-stimulation tDCS

A unified intrinsic functional expansion theory for solitary waves

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Acta Mechanica Sinica 2005年第1期21卷 1-15页

作者： theodore Yaotsu Wu John Kao Jin e.Zhang California Institute of Technology Pasadena.CA 91125U.S.A.FellowInstitute of MechanicsChinese Academy of SciencesBeijing 100080China Warner Brothers GlendaleCA 91203.U.S.A. The university of Hong Kong.Pokfulam Road.Hong Kong SAR.China

A new theory is developed here for evaluating solitary waves on water, with results of high accuracy uniformly valid for waves of all heights, from the highest wave with a corner crest of 120 down to very low ones of diminishing height. Solutions are sought for the euler model by employing a unified expansion of the logarithmic hodograph in terms of a set of intrinsic component functions analytically determined to represent all the intrinsic properties of the wave entity from the wave crest to its outskirts. The unknown coefficients in the expansion are determined by minimization of the mean-square error of the solution, with the minimization optimized so as to take as few terms as needed to attain results as high in accuracy as attainable. In this regard, Stokess formula, F2= tan , relating the wave speed (the Froude number F) and the logarithmic decrement of its wave field in the outskirt, is generalized to establish a new criterion requiring (for minimizing solution error) the functional expansion to contain a finite power series in M terms of Stokess basic term (singular in ), such that 2M is just somewhat beyond unity, i.e. 2M1. This fundamental criterion is fully validated by solutions for waves of various amplitude-to-water depth ratio =a/h, especially about 0.01, at which M=10 by the criterion. In this pursuit, the class of dwarf solitary waves, defined for waves with 0.01, is discovered as a group of problems more challenging than even the highest wave. For the highest wave, a new solution is determined here to give the maximum height hst=0.8331990, and speed Fhst=1.290890, accurate to the last significant figure, which seems to be a new record.

关键词： Solitary waves on water Unified intrinsic functional expansion theory exact solutions High-accuracy computation of waves of arbitrary height Mass and energy transfer

Practical application of the neuroregenerative properties of ketamine: real world treatment experience

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Neural Regeneration Research 2016年第2期11卷 195-200页

作者： theodore A.Henderson Neuro-Luminance The Synaptic Space Neuro-Laser Foundation

While controversial, ketamine has emerged as an effective treatment for refractory depression. Serial infusions have been performed 3 times per week, but our practical experience has challenged this precept concerning infusion frequency. Depression is associated with neuron loss, reduced synapse numbers, and dearborization of dendrites. Ketamine appears to potently induce mechanisms which reverse these neurodegenerative processes. Ketamine not only blocks the glutamate receptor, it activates eukaroyotic elongation factor 2（e eF2）. This, in turn, activates brain-derived neurotrophic factor（BDNF） protein synthesis. This is thought to underlie ketamine＇s enduring benefits. In addition, ketamine alters glycogen synthase kinase-3（GSK-3） phosphorylation, probably responsible for its rapid antidepressant effect. Notably, inhibition of the BDNF receptor does not block the immediate benefits of ketamine, but does prevent the enduring effects. Neuro-Luminance Ketamine Infusion Centers have been treating patients with serial ketamine infusions for over three years. Our methods differ from what is often reported, as we perform infusions only once per week and generally do not perform more than five infusions. Data from 100 patients showed that 80% of the patients responded. The baseline Quick Inventory of Depressive Symptomatology-Self Report（QIDS-SR） score was 17.8 ± 2.8. Responders to ketamine showed a drop in QIDS-SR score of 10.8 ± 3.5, while non-responders showed a 0.8 ± 1.8 change. Moreover, they often had persistent benefits over several months. Recently, it was proposed that psychotomimetic effects are necessary during a ketamine infusion to yield effective antidepressant benefits. Yet, only one patient in our clinic has experienced hallucinations in three years. Nevertheless, 80% of our patients show clinical improvement. Further studies of clinical methods for ketamine infusion therapy are encouraged.

关键词： Ketamine brain-derived neurotrophic factor infusion therapy depression safety

Development of precision medicine approaches based on inter-individual variability of BCRP/ABCG2

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Acta Pharmaceutica Sinica B 2019年第4期9卷 659-674页

作者： Liming Chen Jose e.Manautou theodore P.Rasmussen Xiao-bo Zhong Department of Pharmaceutical Sciences School of Pharmacy University of Connecticut

Precision medicine is a rapidly-developing modality of medicine in human *** on each patient’s unique characteristics, more accurate dosages and drug selection can be made to achieve better therapeutic efficacy and less adverse reactions in precision medicine. A patient’s individual parameters that affect drug transporter action can be used to develop a precision medicine guidance, due to the fact that therapeutic efficacy and adverse reactions of drugs can both be affected by expression and function of drug transporters on the cell membrane surface. The purpose of this review is to summarize unique characteristics of human breast cancer resistant protein(BCRP) and the genetic variability in the BCRP encoded gene ABCG2 in the development of precision medicine. Inter-individual variability of BCRP/ABCG2 can impact choices and outcomes of drug treatment for several diseases, including cancer chemotherapy. Several factors have been implicated in expression and function of BCRP, including genetic, epigenetic, physiologic,pathologic, and environmental factors. Understanding the roles of these factors in controlling expression and function of BCRP is critical for the development of precision medicine based on BCRP-mediated drug transport.

关键词： BCRP epigenetics Gene polymorphisms Physiologic factors Precision medicine

On solitary *** 2 A unified perturbation theory for higher-order waves

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Acta Mechanica Sinica 2005年第6期21卷 515-530页

作者： theodore Yaotsu Wu Xinlong Wang Wendong Qu California Institute of Technology Pasadena CA 91125 U.S.A. Fellow Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Modern Acoustics and Institute of Acoustics Nanjing University Nanjing 210093 China California Institute of Technology Pasadena CA 91125 U.S.A PIMCO Newport Beach CA 92660 U.S.A.

A unified perturbation theory is developed here for calculating solitary waves of all heights by series expansion of base flow variables in powers of a small base parameter to eighteenth order for the one-parameter family of solutions in exact form, with all the coefficients determined in rational numbers. Comparative studies are pursued to investigate the effects due to changes of base parameters on （i） the accuracy of the theoretically predicted wave properties and （ii） the rate of convergence of perturbation expansion. Two important results are found by comparisons between the theoretical predictions based on a set of parameters separately adopted for expansion in turn. First, the accuracy and the convergence of the perturbation expansions, appraised versus the exact solution provided by an earlier paper [1] as the standard reference, are found to depend, quite sensitively, on changes in base parameter. The resulting variations in the solution are physically displayed in various wave properties with differences found dependent on which property （e.g. the wave amplitude, speed, its profile, excess mass, momentum, and energy）, on what range in value of the base, and on the rank of the order n in the expansion being addressed. Secondly, regarding convergence, the present perturbation series is found definitely asymptotic in nature, with the relative error δ （n）（the relative mean-square difference between successive orders n of wave elevations） reaching a minimum, δm at a specific order, n = n both depending on the base adopted, e.g. nm,α= 11-12 based on parameter α （wave amplitude）, nm,δ = 15 on δ （amplitude-speed square ratio）, and nm.ε= 17 on ε （ wave number squared）. The asymptotic range is brought to completion by the highest order of n = 18 reached in this work.

关键词： Solitary waves on water Unified perturbation theory Base functions Base parameters Asymptotic representation

Interaction of genotype and environment effects on important traits of cassava(Manihot esculenta Crantz)

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The Crop Journal 2017年第5期5卷 373-386页

作者： Athanase Nduwumuremyi Rob Melis Paul Shanahan Asiimwe theodore University of KwaZulu-Natal African Center for Crop Improvement (ACCI) Rwanda Agriculture Board (RAB)

General and specific environmental adaptation of genotypes is the main goal of ***, genotype-by-environment(G x e) interaction complicates the identification of genotypes for release. This study aimed at analyzing the effects of G x e interaction on the expression of important cassava traits using two multivariate analyses: additive main effects and multiplicative interaction(AMMI) and genotype stability index(GSI). Total carotene content(TCC), postharvest physiological deterioration(PPD), and reaction to viral diseases were significantly affected by G x e interaction effects. The low percent(%)variation due to genotype for cassava brown streak disease(GBSD) explained the influence of environment on CBSD expression. The % variation due to genotype for TCC was higher(96%) than variation due to environment(1.7%) and G x e interaction(2.4%) indicating a low interaction effect of environment on TCC accumulation. The % variation due to genotype was higher than % variation due to environment for all traits but CBSD root necrosis and CBSD on stems, indicating the influence of environment on the severity of the viral diseases. These findings indicate that screening for disease resistance requires multi-environment trials, whereas a single-environment trial suffices to screen for total carotene content.

关键词： Additive main effects and multiplicative interaction Genotype adaptation Genotype stability index Physiological postharvest deterioration Total carotene content

Directional neighbor discovery in mmWave wireless networks

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Digital Communications and Networks 2021年第1期7卷 1-15页

作者： Yu Wang Ticao Zhang Shiwen Mao theodore(Ted)S.Rappaport Department of electrical and Computer engineering Auburn UniversityAuburnAL36849-5201USA NYU WIReLeSS Center NYU Tandon School of EngineeringBrooklynNY11201USA

The directional neighbor discovery problem,i.e,spatial rendezvous,is a fundamental problem in millimeter wave(mmWave)wireless networks,where directional transmissions are used to overcome the high *** challenge is how to let the transmitter and the receiver beams meet in space under deafness caused by directional transmission and reception,where no control channel,prior information,and coordination are *** this paper,we present a Hunting based Directional Neighbor Discovery(HDND)scheme for ad hoc mmWave networks,where a node follows a unique sequence to determine its transmission or reception mode,and continuously r0-tates its directional beam to scan the neighborhood for other mmWave *** a rigorous analysis,we derive the conditions for ensured neighbor discovery,as well as a bound for the worst-case discovery time and the impact of *** validate the analysis with extensive simulations and demonstrate the superior perfor-mance of the proposed scheme over several baseline schemes.

关键词： Fifth generation(5G)wireless Beamforming Spatial fltering Directional antenna Directional neighbor discovery Initial access Milimeter wave(mmWave)networks Spatial rendezvous