A5090486608- Advanced MRI Techniques and Applications
- Atomic and Subatomic Physics Research
- Advanced NMR Techniques and Applications
- Medical Imaging Techniques and Applications
- NMR spectroscopy and applications
- Ultrasonics and Acoustic Wave Propagation
- Radiation Detection and Scintillator Technologies
- Ultrasound and Hyperthermia Applications
- Metamaterials and Metasurfaces Applications
- Ultrasound Imaging and Elastography
- Superconducting Materials and Applications
- Muscle Physiology and Disorders
- Advanced Neuroimaging Techniques and Applications
- Electron Spin Resonance Studies
- Geophysical Methods and Applications
- Lanthanide and Transition Metal Complexes
- Nuclear Physics and Applications
- Energy Harvesting in Wireless Networks
- Concrete and Cement Materials Research
- Osteoarthritis Treatment and Mechanisms
- Characterization and Applications of Magnetic Nanoparticles
- Pain Management and Placebo Effect
- Wireless Power Transfer Systems
- Terahertz technology and applications
- Musculoskeletal pain and rehabilitation
Universidad Nacional Autónoma de México
2014-2023
Universidad Autónoma de la Ciudad de México
2019
Brookhaven National Laboratory
2006-2012
Universidad Autónoma Metropolitana
2006
Magnetic resonance imaging and spectroscopy rely on the magnetic fields generated by radiofrequency volume coils to acquire high-quality data. Consequently, a comprehensive understanding of electromagnetic field behavior in RF is essential for optimizing techniques designing advanced coils. This study introduces theoretical model birdcage coil, based spherical geometry approach. To validate proposed model, phantom images were acquired at different resonant frequencies, produced coil was...
The ability to acquire high resolution anatomical data as well quantitative functional information in vivo is becoming an increasingly important factor the diagnosis of disease. Simultaneous acquisition PET and MRI would provide essentially perfect co-registration between two images which particularly for tissues whose position shape can change sequential scans. RatCAP a complete 3D tomograph that designed image brain awake rat. A special coil composed 2 saddle elements working quadrature...
In cement-based materials porosity plays an important role in determining their mechanical and transport properties. This paper describes improved low–cost embeddable miniature NMR sensor capable of non-destructively measuring evaporable water loss refinement low high water-to-cement ratio materials. The consists two NdFeB magnets having North South poles facing each other, separated by 7 mm to allow space for a Faraday cage containing Teflon tube ellipsoidal RF coil. To account magnetic...
We are developing a scanner that will allow the simultaneous acquisition of high resolution anatomical data using Magnetic Resonance Imaging (MRI) and quantitative physiological Positron Emission Tomography (PET). The approach is based on technology used for RatCAP conscious small animal PET tomograph which utilizes block detectors consisting pixelated arrays LSO crystals read out with matching avalanche photodiodes (APDs) custom-designed ASIC. A version detector being developed be...
Split ring resonators (SRRs) have been used extensively in metamaterials, showing a strong localization and enhancement of fields, which significantly improves the sensitivity resolution electromagnetic field sensors. We propose development an electric sensor for 2.4 GHz industrial, scientific, medical (ISM) band applications, by modifying renowned SRR to contain three concentric pairs rings. The reduced size makes affordable experiments inserting it phantoms order measure specific...
The design and construction of an ultrasonic pulser is part a multichannel system, for the analysis, monitoring characterization heterogeneous highly dispersive materials. has been built on FPGA platform allowed to modify pulse repetition rate, width number pulses burst. This open architecture basic module more complex pulser, such as arbitrary generator. results show transducer responses under above parameters.
This work presents a flexible metasurface to improve the B1 and image SNR of transceiver quadrature birdcage coil for preclinical MRI applications at 7 T. The was not tuned so no passive components were used. imaging phantom entirely covered with produced an improvement both SNR. easy-to-implement approach offers alternative field high field.
We propose a method to remotely acquire MR images at 7 T with preclinical imager using bio-inspired surface coil, parallel-plate waveguide and non-selective metamaterial. Phantom were acquired without flexible metasurface inserted in cylindrical phantom filled saline solution birdcage coil. Uniformity profiles computed for all cases showing that the coil have very good correspondance. An improvement was observed obtained metasurface. This approach offers convenient alternative high quality images.
A bio-inspired surface coil was built for preclinical MRI applications at 7 T. Images were acquired with and without a flexible metasurface partially cover cylindrical phantom. obtained the metamaterial showed an important improvement of performance. No electronic components used tuning metasurface. This easy-to-implement approach offers alternative to improve SNR high field.
Motivation: The utilization of traveling-wave MRI in conjunction with a parallel-plate waveguide provides an alternative for acquiring images at ultrahigh magnetic fields, circumventing the resonant frequency limitations. Goal(s): To improve image quality and to investigate application metamaterials within performance. Approach: A bio-inspired surface coil transceiver mode C-shaped unit metamaterial made from copper sheets laminated onto nonconductive board filled saline solution were used....
Motivation: The main goal is to enhance the performance of an RF coil used in preclinical MRI imaging, specifically at a field strength 7 T. Goal(s): researchers proposed modification standard birdcage (BC) coil. This involves adding "chain mail layout" rungs Approach: idea for chain layout was inspired by previous low pass wiring schemes coils, as reported Mansfield. Chain refers type flexible armor composed interlinked metal rings. Results: Phantom images were acquired and compute...
Abstract A surface radio frequency coil was developed for small animal image acquisition in a pre-clinical magnetic resonance imaging system at 7 T. flexible composed of two circular loops to closely cover the object be imaged. Electromagnetic numerical simulations were performed evaluate its performance before construction. An analytical expression mutual inductance as function separation between them derived and used validate simulations. The RF is with 5 cm external diameter tuned 300 MHz...
Abstract Objective A volume coil with squared slots-end ring was developed to attain improved sensitivity for imaging of rat’s brain at 7 T. Material and Methods The principles the high cavity resonator low-pass case law Biot-Savart were used derive a theoretical expression $$B_1/i$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>B</mml:mi> <mml:mn>1</mml:mn> </mml:msub> <mml:mo>/</mml:mo> <mml:mi>i</mml:mi> </mml:mrow> </mml:math> . slotted-end...
Acoustic wave propagation in heterogeneous and dispersive media is a very complex phenomenon, where the phase velocity attenuation are function of material microstructure, becomes frequency-dependent parameters. In this paper, interaction between ultrasound waves cement-paste specimens have been analyzed by two multiple scattering models, based on homogenization approach, experimental data. The velocity, dispersion results show good agreement with theoretical models; decrease for higher w/c...
Animal models in medical research has been used to study humans diseases for several decades. The use of different imaging techniques together with animal offers a great advantage due the possibility some human pathologies without necessity chirurgical intervention. employ magnetic resonance acquisition anatomical and functional images is an excellent tool because its noninvasive nature. Dedicated coils perform experiments are obligatory improvement on signal-to-noise ratio reduced specific...
Abstract Malnutrition during brain development can cause serious problems that be irreversible. Dysfunctional patterns of activity detected with functional MRI. We used BOLD Magnetic Resonance Imaging (fMRI) to investigate region differences between control and malnourished rats. The food-competition method was applied a rat model induce malnutrition lactation. A 7T magnet detect changes the signal associated in caused by trigeminal nerve stimulation Major neuronal activation observed rats...
Reinforced concrete structures require regular assessment of their structural integrity. The effects mechanical loading and environmental on produce micro-cracks, reducing the overall strength stiffness while increasing permeability to aggressive species. Water carrying species such as chloride ions can then travel through these small channels, reaching reinforcing steel causing corrosion. It also be a starting point for larger cracks. This is particularly important since it may...
We looked for a biological analogy to developed an improved surface coil acquire magnetic resonance images. Nature offers engineering solutions that can be exploited improve the performance of devices, such as MRI RF coils. In this paper, we proposed layout based on flower petal patterns UHF at 15.2 T. This particular configuration possibility use different number petals and shapes. The resonator magnetron have similar layouts, which proved outperform popular circular coil. Phantom images...
A volume coil with squared slots-end ring was developed to attain improved sensitivity for imaging of rat's brain at 7 T. The principles the high cavity resonator low-pass case and law Biot-Savart were used derive a theoretical expression sensitivity. slotted-end showed 2.22-fold improvement over standard birdcage similar dimensions. Numerical studies carried out electromagnetic fields specific absorption rates our loaded saline-filled cylindrical phantom digital rat. An signal-to-noise...
The use of the travelling wave approach for high magnetic field resonance imaging has been used recently with very promising results. This offer images one greater field-of-view and a reasonable signal-to-noise ratio using circular waveguide. scheme proved to be successful at 7 T 9.4 whole-body imager. Images have also acquired clinical systems whose resonant frequencies were 64 MHz 128 MHz. These results motivated remote detection signal parallel-plate waveguide together 3 scanners, human...