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Open Journal of Medical Imaging 2021年第3期11卷 85-91页

作者： Ana Carla Farias Pimentel Mariana Santos Leite Pessoa Francisca Estefânia Mesquita Maciel de Lima manuel joaquim diógenes teixeira Cláudio Régis Sampaio Silveira Ana Carla Farias Pimentel MD Radiologist Hospital Geral de Fortaleza (HGF) Fortaleza-CE Brazil Mariana Santos Leite Pessoa MD Radiology Resident Hospital Geral de Fortaleza (HGF) Fortaleza-CE Brazil Francisca Estefania Mesquita Maciel de Lima MD Pathologist Laboratório Mikros Fortaleza-CE Brazil manuel joaquim diógenes teixeira MD Orthopedist Hospital Geral de Fortaleza (HGF) Fortaleza-CE Brazil Cláudio Régis Sampaio Silveira MD Radiologist Hospital Geral de Fortaleza (HGF) Fortaleza-CE Brazil Hospital S?o Carlos Fortaleza-CE Brazil

Vertebral hemangiomas are common benign lesions of the spine, characterized by abnormal vascular proliferation, being commonly asymptomatic incidental findings, presenting symptoms in only a small portion of affected individuals. In a smaller number of cases, however, hemangiomas can present an expansive effect and extra-osseous extension, determining a mass effect and neurological symptoms, being therefore called aggressive hemangiomas. On MRI, aggressive hemangiomas are characterized by having a larger vascular component and a smaller fat component, thus producing a low signal on T1-weighted images. We illustrate the case of a young male patient who presented with pain in the upper thoracic spine, who developed paraparesis and ascending sensory deficit and progressive lower limbs, progressing to paraplegia and loss of sphincter control.

关键词： Aggressive Vertebral Hemangioma Compressive Myelopathy Magnetic Resonance Imaging

Fabrication of cost-effective, highly reproducible large area arrays of nanotriangular pillars for surface enhanced Raman scattering substrates

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Nano Research 2016年第10期9卷 3075-3083页

作者： Kudilatt Hasna Aldrin Antony joaquim Puigdollers Kumaran Rajeev Kumar Madambi Kunjukuttan Jayaraj Nanophotonic & Optoelectronic Devices Laboratory Department of Physics Cochin University of Science & Technology Kochi 682 022 India Department of Instrumentation Cochin University of Science & Technology Kochi 682 022 India Department of Energy Science and Engineering Indian Institute of Technology Bombay Maharashtra 400 076 India Department of Enginyeria Electronica Universitat Politecnica Catalunya C/Jordi Girona 31 Modul C4 Barcelona 08034 Spain

Development of cost-effective, highly reproducible non-conventional fabrication techniques for anisotropic metal nanostructures is essential to realizing potential applications of plasmonic devices, photonic devices, and surface enhanced Raman scattering （SERS） phenomenon based sensors. This report highlights the fabrication of nanotriangle arrays via nanoimprinting to overcome difficulties in creating large-area SERS active substrates with uniform, reproducible Raman signals. Electron beam lithography of anisotropic nanostructures, formation of arrays of nanotriangles in silicon and the transfer of triangular shapes to polymethylmethacrylate （PMMA） sheets via nanoimprinting have not been reported elsewhere. The reuse of silicon masters offers potential for production of low cost SERS substrates. The SERS activity and reproducibility of nanotriangles are illustrated and a consistent average enhancement factor of up to -2.9 × 1011, which is the highest value reported for a patterned SERS substrate, is achieved.

关键词： metal nanostructures localized surface plasmon resonance (LSPR) surface enhanced Ramanscattering (SERS) substrate enhancement factor

Comparison of the Internal Structures of Bones by Microtomography

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Journal of Chemistry and Chemical Engineering 2017年第2期11卷 51-54页

作者： Julio Cesar Latini Stutz Joel. Sanchez Dominguez joaquim teixeira de Assis DEMEC/LEFI/IPRJ Universidade do Estado do Rio de Janeiro 28625-570 Nova Friburgo-RJ Brazil Universidade Estacio de Sa Nova Friburgo Rio de Janeiro Brazil

The use of computed microtomography （***） has revolutionized many areas of research, such as noninvasive, fast and high precision techniques, which allows immediate visualization of internal structures without any risk to the object of study. ~tCT is widely accepted for medical diagnostics, is also important for purposes of zoological research and paleontological. In this work, we used the μCT to investigate the internal structure of bones from mammalian and poultry. We studied the bones of rats and quail. Through microtomography images, we observed that the bones of the poultry have a bony structure in the form of a trellis that is not present in bones of mammals. These trellises bony is an evolutionary adaptation that allowed the bones of the birds to become longer and lighter maintaining its strength. It was also observed that the percentage of the trabecular area in poultry is almost half of that observed in mammals. The results obtained validate the use of μCT as a technique that allows the study of bone structures in small samples, enabling to explore the morphological differences between the bones of those species.

关键词： Microtomography bones X-ray.

Using Graphics Processing Units to Parallelize the FDK Algorithm for Tomographic Image Reconstruction

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Journal of Chemistry and Chemical Engineering 2012年第8期6卷 760-768页

作者： Joel Sancnchez Dominguez Luiz Femando de Oliveira Nilton Alves Junior joaquim teixeira de Assis Politechnical Institute of Rio de Janeiro State University Nova Friburgo-RJ 28625-570 Brazil Physics Institute of Rio de Janeiro State University Rio de Janeiro 20550-900 Brazil Brazilian center for physical research Rio de Janeiro 22290-180 Brazil

The paper presents the implementation of a parallel version of FDK （Felkamp, David e Kress） algorithm using graphics processing units. discussion was briefly some elements the computed tomographic scan and FDK algorithm; and some ideas about GPUs （Graphics Processing Units） and its use in general purpose computing were presented. The paper shows a computational implementation of FDK algorithm and the process of parallelization of this implementation. Compare the parallel version of the algorithm with the sequential version, used speedup as a performance metric. To evaluate the performance of parallel version, two GPUs, GeForce 9400GT （16 cores） a low capacity GPU and Quadro 2000 （192 cores） a medium capacity GPU was reached speedup of 3.37.

关键词： Computed tomography images reconstruction FDK algorithm GPUs CUDA-C parallel processing.

discogenic pain: Who cares?

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Health 2013年第11期5卷 1929-1937页

作者： Jose Pedro Lavrador Nuno Simas Edson Oliveira joaquim Cruz teixeira diogo Simao Sergio Livraghi Neurosurgical Department Hospital Santa MariaLisbonPortugal

Chronic low back pain has a huge impact on daily living and a negative economic and professional effect. It is a matter of debate and concern for all health professionals involved, particularly spine surgeons. Recent discoveries on the innervation and biochemical properties of the intervertebral disc clarify the role of this structure as a possible cause of chronic low back pain. However, multiple causes may be present in the same patient making the diagnosis a challenging process. discogenic pain is defined as a chronic low back pain induced by a degenerative disc disease. There are no specific characteristics of discogenic pain, although it has a higher incidence in younger age, it is usually localized medially in the back, worsens with axial loading and improves with recumbence. In the last decades we have assisted the emergence of multiple treatment techniques. However, neither the conservative treatment nor the interventional management has strong evidence in treating discogenic pain. Randomized control clinical trials are sought to improve patient outcome. Meanwhile, we believe each patient should be approached on an individual base. discogenic pain: we care.

关键词： discogenic Pain Low Back Pain Intervertebral disc

Obtaining Porosity of Concrete Using X-ray Microtomography or digital Scanner

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Journal of Chemistry and Chemical Engineering 2014年第4期8卷 371-377页

作者： Jose Renato de Castro Pessoa Joel Sanchez Dominguez Gil de Carvalho joaquim teixeira de Assis Politechnical Institute of Rio de Janeiro State University Nova Friburgo 28625-570 Brazil

The aim of this work is to determine the porosity of concrete by means of two NDT （non-destructive testing） using digital images. In one test, the images were obtained through X-ray microtomography and for another test via digital scanner. In both of the tests, the images were processed using techniques of mathematical morphology and pixel processing. For both NDT, it was used concrete samples with 20-30 MPa of compressive strength. The results for the porosity were compared with results obtained by the standard test proposed by NBR （Norma Brasileira） 9778 （2005） showing the compatibility between two studied methods and pattern method.

关键词： Concrete porosity X-ray microtomographic images processing matematical morfology.

Optimization of LiMn_2O_4 electrode properties in a gradient-and surrogate-based framework

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Acta Mechanica Sinica 2013年第3期29卷 335-347页

作者： Wenbo Du Nansi Xue Amit Gupta Ann M.Sastry joaquim R.R.A.Martins Wei Shyy Department of Aerospace Engineering University of Michigan Department of Mechanical Engineering Indian Institute of Technology Department of Mechanical Engineering University of Michigan Department of Mechanical Engineering Hong Kong University of Science and Technology Clear Water Bay

In this study, the effects of discharge rate and LiMn2O4 cathode properties （thickness, porosity, particle size, and solid-state diffusivity and conductivity） on the gravimetric energy and power density of a lithium-ion battery cell are analyzed simultaneously using a cell-level model. Surrogate-based analysis tools are applied to simulation data to construct educed-order models, which are in turn used to perform global sensitivity analysis to compare the relative importance of cathode properties. Based on these results, the cell is then optimized for several distinct physical scenarios using gradient-based methods. The comple-mentary nature of the gradient-and surrogate-based tools is demonstrated by establishing proper bounds and constraints with the surrogate model, and then obtaining accurate optimized solutions with the gradient-based optimizer. These optimal solutions enable the quantification of the tradeoffs between energy and power density, and the effect of optimizing the electrode thickness and porosity. In conjunction with known guidelines, the numerical optimization frame-work developed herein can be applied directly to cell and pack design.

关键词： Lithiumion battery Optimization Surrogate modeling Porous electrode model

Layered double hydroxide(LDH)-based materials:A mini-review on strategies to improve the performance for photocatalytic water splitting

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Journal of Energy Chemistry 2022年第1期31卷 406-431,I0011页

作者： Hanane Boumeriame Eliana S.Da Silva Alexey S.Cherevan Tarik Chafik joaquim L.Faria Dominik Eder Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials(LSRE-LCM) Faculdade de EngenhariaUniversidade do PortoRua Dr Roberto Frias s/n4200-465 PortoPortugal Institute of Materials Chemistry Technische Universicat Wien(TU Wien)Getreidemarkt 9Vienna 1060Austria Laboratory of Chemical Engineering and Valorization of Resources(LGCVR-UAE/L01FST).Faculte des Sciences et Techniques Universite Abdelmalek EssaadiTangierMorocco

The high energy demand we currently face in society and the subsequent large consumption of fossil fuels cause its depletion and increase the pollution *** quest for the production of clean energy from renewable and sustainable sources remains *** conversion of solar energy into hydrogen via the water-splitting process,assisted by pho tores pons ive semiconductor catalysts,is one of the most promising *** progress has been made on water splitting in the past few years and a variety of photocatalysts active not only under ultra-violet(UV) light but especially with the visible part of the electromagnetic spectrum have been *** double hydroxides(LDH)-based materials have emerged as a promising class of nanomaterials for solar energy applications owing to their unique layered structure,compositional flexibility,tunable bandgaps,ease of synthesis and low manufacturing *** review covers the most recent research dedicated to LDH materials for photocatalytic water-splitting applications and encompasses a range of synthetic strategies and post-modifications used to enhance their ***,we provide a thorough discussion of the experimental conditions crucial to obtaining improved photoactivity and highlight the impact of some specific parameters,namely,catalysts loading,cocatalysts,sacrificial agents,and irradiation *** review provides the necessary tools to select the election technique for adequately enhancing the photoactivity of LDH and modified LDH-based materials and concludes with a critical summary that outlines further research directions.

关键词： Layered double hydroxides Water splitting Photocatalysis Hydrogen generation Oxygen evolution Nanomaterials

3D Surface velocity retrieval of mountain glacier using an offset tracking technique applied to ascending and descending SAR constellation data:a case study of the Yiga Glacier

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International Journal of digital Earth 2019年第6期12卷 614-624页

作者： Qun Wang Jinghui Fan Wei Zhou Liqiang Tong Zhaocheng Guo Guang Liu Weilin Yuan joaquim Joao Sousa Zbigniew Perski School of Land Science and Technology China University of GeosciencesBeijingPeople’s Republic of China division of Remote Sensing for Environment China Aero Geophysical Survey and Remote Sensing Center for Land and ResourcesBeijingPeople’s Republic of China Key Laboratory of digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China School of Sciences and Technology University of Trás-os-Montes e Alto DouroVila RealPortugal Centre for Robotics in Industry and Intelligent Systems INESC TECPortoPortugal Polish Geological Institute—National Research Institute CracowPoland

COSMO-SkyMed is a constellation of four X-band high-resolution radar satellites with a minimum revisit period of 12 *** satellites can obtain ascending and descending synthetic aperture radar(SAR)images with very similar periods for use in the three-dimensional(3D)inversion of glacier *** this paper,based on ascending and descending COSMO-SkyMed data acquired at nearly the same time,the surface velocity of the Yiga Glacier,located in the Jiali County,Tibet,China,is estimated in four directions using an offset tracking technique during the periods of 16 January to 3 February 2017 and 1 February to 19 February *** the geometrical relationships between the measurements and the SAR images,the least square method is used to retrieve the 3D components of the glacier surface velocity in the eastward,northward and upward *** results show that applying the offset tracking technique to COSMO-SkyMed images can be used to derive the true 3D velocity of a glacier’s *** the two periods,the Yiga Glacier had a stable velocity,and the maximum surface velocity,2.4 m/d,was observed in the middle portion of the glacier,which corresponds to the location of the steepest slope.

关键词： Mountain glacier inversion of 3D movement offset tracking SAR constellation data