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A Simple mathematical Formulation of the Correspondence Principle

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journal of modern Physics 2013年第1期4卷 108-112页

作者： j. Bernal A. martín-ruiz j. C. García-melgarejo Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. México Instituto Nacional de Astrofísica óptica y Electrónica Santa María Tonantzintla México Universidad juárez Autónoma de Tabasco División Académica de Ciencias Básicas Cunduacán México

In this paper we suggest a simple mathematical procedure to derive the classical probability density of quantum systems via Bohr’s correspondence principle. Using Fourier expansions for the classical and quantum distributions, we assume that the Fourier coefficients coincide for the case of large quantum number. We illustrate the procedure by analyzing the classical limit for the quantum harmonic oscillator and the particle in a box, although the method is quite general. We find, in an analytical fashion, the classical distribution arising from the quantum one as the zeroth order term in an expansion in powers of Planck’s constant. We interpret the correction terms as residual quantum effects at the microscopic-macroscopic boundary.

关键词： Correspondence Principle Classical Limits

Use of <i>Rosmarinus officinalis</i>as Green Corrosion Inhibitor for Carbon Steel in Acid medium

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American journal of Analytical Chemistry 2014年第2期5卷 55-64页

作者： m. A. Velázquez-González j. G. Gonzalez-Rodriguez m. G. Valladares-Cisneros I. A. Hermoso-diaz Universidad Autonoma del Estado de morelos CIICAp Col. Chamilpa Cuernavaca Mexico Universidad Autonoma del Estado de morelos FCQeI Col. Chamilpa Cuernavaca Mexico

The use of Rosmarinus officinalis as a corrosion inhibitor for 1018 carbon steel in 0.5 m H2SO4 has been evaluated by using weight loss, potentiodynamic polarization curves and electrochemical impedance spectroscopy techniques at 25°. Inhibitor concentrations were included within the range between 0 and 1000 ppm C using three extract solvents, namely acetone, hexane and methanol. Results have shown that Rosmarinus officinalis is a good corrosion inhibitor with its efficiency increasing with the concentration. The best efficiency was obtained with the hexanic extract. The passivating film properties of the steel were improved by the presence of flavonoids in the extract.

关键词： metals Corrosion Fourier Transform Infrared Spectroscopy Electrochemical Techniques

利用全身扩散加权mRI和FDG PET/mRI评估儿童肿瘤治疗反应

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国际医学放射学杂志 2020年第5期 611-612页

作者： A.j.Theruvath F.Siedek A.m.muehe j.Garcia-diaz j.Kirchner O.martin 刘思睿 Department of Radiology Molecular Imaging Program at Stanford Stanford University

摘要全身扩散加权(DW)mRI在检测肿瘤方面具有较高的敏感性。然而,肿瘤疗效的评估通常需要肿瘤代谢的相关信息,这种代谢信息可以通过氟-18-氟脱氧葡萄糖(FDG)

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Probabilistic tractography of the posterior subthalamic area in Parkinson’s disease patients

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journal of Biomedical Science and Engineering 2013年第3期6卷 381-390页

作者： m.G.GarcIa-Gomar Luis Concha S.Alcauter j.Soto Abraham j.D.Carrillo-ruiz G.Castro Farfan Francisco Velasco Campos Neurobiology Institute UNAM Campus JuriquillaJuriquillaQueretaroMexico National Institute of Psychiatry“Ramón de la Fuente muniz” México CityMéxico Unit for Stereotactic and Functional Neurosurgery and Radiosurgery México General HospitalMéxico CityMéxico

Deep brain stimulation (DBS) is a non-pharmacological treatment for Parkinson’s disease (PD), and its efficacy depends largely on which anatomical structure (target) is stimulated. The subthalamic nucleus (STN) is one of the most commonly used targets, but stimulation of new targets within the posterior sub-thalamic area (PSA), comprising a group of white matter fibers known as prelemniscal radiations (Raprl), as well as the caudal zonaincerta nucleus (Zic), have proven to be superior at improving certain clinical symptoms. Despite their clinical usefulness, their anatomical connectivity has not been completely described in humans. We performed constrained spherical deconvolution of the signal in diffusion-weighted images and subsequent tractography as a means to non-invasively define the connectivity of the Raprl and Zic in a group of five patients with PD. Further, we used track-density imaging, a novel method to improve the spatial resolution of the acquired images, in order to visualize the small subregions that comprise the PSA with a voxel resolution of 0.2 × 0.2 × 0.2 mm3. Both Raprl and Zic demonstrated high probability of connectivity with the dorsal brainstem, cerebellum, subcortical nuclei (globus pallidum ventral, lateral thalamic nuclei), and cortical areas (orbitofrontal cortex, primary and supplementary motor cortex areas). The connectivity patterns were re-producible between patients and were discretely organized as the tracts entered/exited the PSA, depending on their end points. These findings indicate that the PSA is part of the neuronal circuitry controlling movement, and the precise characterization of its connectivity will aid in our understanding of the net-works involved in PD and how they can be modulated with DBS in order to alleviate symptoms.

关键词： Parkinson Disease(PD) Posterior Subthalamic Area(PSA) Tractography Track-Density Images(TDI)

The Classical Limit of the Quantum Kepler Problem

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journal of modern Physics 2013年第6期4卷 818-822页

作者： A. martín-ruiz j. Bernal Alejandro Frank Adrián Carbajal-Dominguez Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. México Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. México Centro de Ciencias de la Complejidad Universidad Nacional Autónoma de México México D.F. México Universidad juárez Autónoma de Tabasco División Académica de Ciencias Básicas Cunduacán México

The classical limit of the quantum mechanical Kepler problem is derived by using a simple mathematical procedure recently proposed. The method is based both on Bohr’s correspondence principle and the local averages of the quantum probability distribution. We illustrate in a clear fashion the difference between Planck’s limit and Bohr’s correspondence principle. We discuss the confinement effect in macroscopic systems.

关键词： Kepler Problem Classical Limits

Probable benign paroxysmal positional vertigo, spontaneously resolved:Incidence in medical practice, patients’ characteristics and the natural course

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journal of Otology 2019年第3期14卷 111-116页

作者： m.G.Alvarez-morujo de Sande R. Gonzalez-Aguado G. Guerra-jimenez E. Domenech-Vadillo H. Galera-ruiz E. Figuerola-massana A. Ramos-macías C. morales-Angulo A.j. martín-mateos E. Domínguez-Duran Hospital Universitario Puerta del mar Cadiz Spain Hospital Universitario marques de Valdecilla Santander Spain Complejo Hospitalario Universitario Insular materno-Infantil Las Palmas de Gran Canaria Spain Hospital Universitari joan XXIII Tarragona Spain Hospital Infanta Luisa Sevilla Spain

Background: Probable benign paroxysmal positional vertigo, spontaneously resolved (pBPPVsr), is a variant of benign paroxysmal positional vertigo (BPPV) in which there is no observable nystagmus and no vertigo with any positional maneuver. Objectives: To calculate the incidence pBPPVsr, compare the characteristics of the patients with pBPPVsr and BPPV not spontaneously resolved and describe the spontaneous resolution in the natural course of BPPV. methods: multicenter prospective descriptive study. During a one-year period, all patients with suspected BPPV that presented to the Neurotology Units of five participating centers were recruited. The incidence of pBPPVsr was calculated as a percentage of the total number of patients with BPPV. The prevalence of several variables was compared between pBPPVsr and BPPV not spontaneously resolved. The timing of spontaneous resolution was estimated using Kaplan-meier curves. Results: 457 patients met the inclusion criteria. The incidence of pBPPVsr was 33.5%. It was significantly higher in males, in patients with normal bone mass and in patients who were not taking sulpiride. A rate of 18% of spontaneous resolution after the first month and 51% after the first year was found. This percentage did not change in a significant way after this moment. The curves for males, patients under 50 and patients with normal blood pressure decreased significantly faster. Conclusions: In our serie, BPPV spontaneously resolved in half of the patients with BPPV during the first year. This seemed to occur more commonly in males and could have been hindered by sulpiride intake, osteoporosis, advanced age and high blood pressure.

关键词： Benign paroxysmal positional vertigo Probable benign paroxysmal positional vertigo, spontaneously resolved Osteoporosis Sulpiride Hypertension

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进展期实体肿瘤对免疫检查点抑制剂有反应的基于CT的影像组学特征

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国际医学放射学杂志 2021年第3期44卷 357-358页

作者： m.Ligero A.Garcia-ruiz C.Viaplana G.Villacampa m.V.Raciti j.Landa 刘春明

摘要目前需要免疫检查点抑制剂做出反应的可靠的预测性影像学标志物。目的建立并验证一种基于治疗前CT的影像组学特征,以预测进展期实体肿瘤对免疫检查点抑制剂

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通过AI自动识别能否减少乳腺X线检查工作量的可行性研究

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国际医学放射学杂志 2019年第6期 745-746页

作者： A.Rodriguez-ruiz K.Lang A.Gubern-merida j.Teuwen m.Broeders G.Gennaro 张凯 Department of Radiology and Nuclear medicine Radboud University Medical Center

摘要目的探讨使用人工智能(AI)自动识别正常数字乳腺X线摄影(Dm)检查的可行性,以减少乳腺癌筛查的阅片工作量。方法从9个先前的多阅片者-多病例受试者操作

关键词：工作量乳腺癌筛查放射科医师 AI 可行性研究

mEP pathway products allosterically promote monomerization of deoxy-D-xylulose-5-phosphate synthase to feedback-regulate their supply

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Plant Communications 2023年第3期4卷 171-182页

作者： supply Xueni Di David Ortega-Alarcon Ramu Kakumanu javier Iglesias-Fernandez Lucia diaz Edward E.K.Baidoo Adrian Velazquez-Campoy manuel Rodríguez-Concepción jordi Perez-Gil Institute for Plant molecular and Cell Biology(IBmCP) CSIC-Universitat Politècnica de València46022 ValenciaSpain 2Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UBCampus UAB Bellaterra08193 BarcelonaSpain 3Institute for Biocomputation and Physics of Complex Systems(BIFI)Joint Unit GBsC-CSIC-BIFIUniversidad de Zaragoza50009 ZaragozaSpain 4Departamento de Bioquímica y Biología Molecular y CelularUniversidad de Zaragoza50009 ZaragozaSpain 5Joint BioEnergy Institute5885 Hollis StreetEmeryvilleCA 94608USA 6Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCA 94720USA 7Nostrum Biodiscovery SL08029 BarcelonaSpain 8Instituto de Investigación Sanitaria de Aragón(IIS Aragon)50009 ZaragozaSpain 9Centro de Investigación Biomédica en Red en elÁrea Temática de Enfermedades Hepáticas y Digestivas(CIBERehd)28029 MadridSpain

Isoprenoids are a very large and diverse family of metabolites required by all living *** isoprenoids derive fromthe double-bond isomers isopentenyl diphosphate(IPP)and dimethylallyl diphosphate(DmAPP),which are produced by the methylerythritol 4-phosphate(mEP)pathway in bacteria and plant *** has been reported that IPP and DmAPP feedback-regulate the activity of deoxyxylulose 5-phosphate synthase(DXS),a dimeric enzyme that catalyzes the main flux-controlling step of the mEP *** we provide experimental insights *** titration calorimetry and dynamic light scattering approaches showed that IPP and DmAPP can allosterically bind to DXS in vitro,causing a size *** silico ligand binding site analysis and docking calculations identified a potential allosteric site in the contact region between the two monomers of the active DXS *** of IPP and DmAPP contents in vivo followed by immunoblot analyses confirmed that high IPP/DmAPP levels resulted in monomerization and eventual aggregation of the enzyme in bacterial and plant *** of the enzymatically active dimeric conformation allows a fast and reversible reduction of DXS activity in response to a sudden increase or decrease in IPP/DmAPP supply,whereas aggregation and subsequent removal of monomers that would otherwise be available for dimerization appears to be a more drastic response in the case of persistent IPP/DmAPP overabundance(e.g.,by a blockage in their conversion to downstream isoprenoids).Our results represent an important step toward understanding the regulation of the mEP pathway and rational design of biotechnological endeavors aimed at increasing isoprenoid contents in microbial and plant systems.

关键词： isoprenoids DXS feedback regulation allosteric monomerization