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1.
Medicine (Baltimore) ; 102(51): e36682, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38134104

RESUMO

RATIONALE: Primary cardiac angiosarcomas (PCA) is a rare malignancy with a poor prognosis. Currently, there is no standard treatment protocol for the PCA. We report a case of PCA in a 51-year-old woman. PATIENT CONCERNS: A 51-year-old woman initially presented with unexplained palpitations and chest tightness accompanied by nausea and vomiting, which worsened after activity and improved after rest. After symptomatic treatment, the symptoms improved, and the above symptoms recurred 8 months later. DIAGNOSES: Positron emission tomography-computed tomography revealed multiple lung nodules of varying sizes, some of which exhibited increased glucose metabolism. Furthermore, a soft tissue mass protruding into the pericardial cavity and involving the adjacent right atrium was observed in the right pericardium. The mass exhibited increased glucose metabolism, suggestive of a pericardial tumor with multiple lung metastases. Finally, histopathologic diagnosis of metastatic angiosarcoma was done by computed tomography-guided percutaneous lung and mediastinal biopsy. INTERVENTIONS: The patient was treated with palliative chemotherapy for the primary cardiac angiosarcomas and hematogenous lung metastasis. One cycle later, the result of Next-Generation Sequencing showed that the microsatellite instability status was determined to be low-level. Based on this result, tislelizumab was added to the original chemotherapy regimen. OUTCOMES: Unfortunately, the patient with PCA passed away after only 2 cycles of chemotherapy, and the cause of death remained unknown. LESSONS: This case report well demonstrates typical imaging findings of a rare cardiac angiosarcomas and emphasizes importance of early investigation for accurate diagnosis and proper management of the cardiac angiosarcomas.


Assuntos
Neoplasias Cardíacas , Hemangiossarcoma , Feminino , Humanos , Pessoa de Meia-Idade , Genes ras , Glucose/metabolismo , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/secundário , Hemangiossarcoma/terapia , Neoplasias Pulmonares/secundário , Instabilidade de Microssatélites , Recidiva Local de Neoplasia/patologia , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/terapia
2.
Micromachines (Basel) ; 13(5)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630250

RESUMO

In this work, we present a method for growing highly c-axis oriented aluminum scandium nitride (AlScN) thin films on (100) silicon (Si), silicon dioxide (SiO2) and epitaxial polysilicon (poly-Si) substrates using a substrate independent approach. The presented method offers great advantages in applications such as piezoelectric thin-film-based surface acoustic wave devices where a metallic seed layer cannot be used. The approach relies on a thin AlN layer to establish a wurtzite nucleation layer for the growth of w-AlScN films. Both AlScN thin film and seed layer AlN are prepared by DC reactive magnetron sputtering process where a Sc concentration of 27% is used throughout this study. The crystal quality of (0002) orientation of Al0.73Sc0.27N films on all three substrates is significantly improved by introducing a 20 nm AlN seed layer. Although AlN has a smaller capacitance than AlScN, limiting the charge stored on the electrode plates, the combined piezoelectric coefficient d33,f with 500 nm AlScN is only slightly reduced by about 4.5% in the presence of the seed layer.

3.
Sensors (Basel) ; 21(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34960260

RESUMO

In this work, the first surface acoustic-wave-based magnetic field sensor using thin-film AlScN as piezoelectric material deposited on a silicon substrate is presented. The fabrication is based on standard semiconductor technology. The acoustically active area consists of an AlScN layer that can be excited with interdigital transducers, a smoothing SiO2 layer, and a magnetostrictive FeCoSiB film. The detection limit of this sensor is 2.4 nT/Hz at 10 Hz and 72 pT/Hz at 10 kHz at an input power of 20 dBm. The dynamic range was found to span from about ±1.7 mT to the corresponding limit of detection, leading to an interval of about 8 orders of magnitude. Fabrication, achieved sensitivity, and noise floor of the sensors are presented.

4.
IEEE Trans Biomed Circuits Syst ; 14(5): 971-984, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32746340

RESUMO

Magnetomyography (MMG) with superconducting quantum interference devices (SQUIDs) enabled the measurement of very weak magnetic fields (femto to pico Tesla) generated from the human skeletal muscles during contraction. However, SQUIDs are bulky, costly, and require working in a temperature-controlled environment, limiting wide-spread clinical use. We introduce a low-profile magnetoelectric (ME) sensor with analog frontend circuitry that has sensitivity to measure pico-Tesla MMG signals at room temperature. It comprises magnetostrictive and piezoelectric materials, FeCoSiB/AlN. Accurate device modelling and simulation are presented to predict device fabrication process comprehensively using the finite element method (FEM) in COMSOL Multiphysics. The fabricated ME chip with its readout circuit was characterized under a dynamic geomagnetic field cancellation technique. The ME sensor experiment validate a very linear response with high sensitivities of up to 378 V/T driven at a resonance frequency of fres = 7.76 kHz. Measurements show the sensor limit of detections of down to 175 pT/√Hz at resonance, which is in the range of MMG signals. Such a small-scale sensor has the potential to monitor chronic movement disorders and improve the end-user acceptance of human-machine interfaces.


Assuntos
Campos Magnéticos , Músculo Esquelético , Simulação por Computador , Humanos
5.
Opt Express ; 28(1): 184-193, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118949

RESUMO

A novel Ge-As-Se-Te chalcogenide glass (ChG)-tapered fiber (ChG-TF) sensor for detecting environmentally relevant organic pollutants with p-xylene as the model was investigated. The prominent design feature of the sensor is that its tapered zone was coated with a polydopamine membrane by a facile in situ self-polymerization process. As the tapered zone exposed to the aqueous sample, the p-xylene molecules would be enriched into the polydopamine coating. The detection limit for p-xylene aqueous solution obtained by the polydopamine-coated sensor was decreased to 50 µg/mL, which was approximately 2.5% that of the uncoated one. To the best of our knowledge, this paper is the first report of a polymer membrane coating, which can significantly enhance the sensitivity of the ChG-TF sensor. The straightforward test features and the capacity of the sensor to detect organic pollutants with as low as ppm range revealed that this sensor has great potential for online, in situ environmental qualification.

6.
Opt Express ; 27(7): 10311-10319, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045175

RESUMO

We demonstrated an ultrabroadband supercontinuum (SC) generation with high coherence property in all-normal-dispersion (ANDi) Te-based chalcogenide tapered fiber. The fibers made of Ge20As20Se15Te45 core and Ge20As20Se20Te40 cladding glasses were fabricated via isolated stacked extrusion. The waist diameter and length can be accurately controlled by a homemade tapering platform. When the core diameter of the waist was ≤14 µm, the fiber showed an ANDi characteristic in the wavelength range of 1.7-14 µm. A coherent SC generation covered 1.7-12.7 µm was generated in a 7-cm-long tapered fiber, pumped at 5.5 µm. To the best of our knowledge, this is the first SC experimental demonstration in Te-based step-index tapered fiber and the broadest SC generation in chalcogenide tapered fiber when pumped in the normal dispersion regime so far.

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