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1.
J Craniofac Surg ; 35(4): 1062-1064, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38408320

RESUMEN

BACKGROUND: Juvenile Psammomatoid Ossifying Fibroma (JPOF) is a type of noncancerous bone tumor that usually affects adolescents in the craniomaxillofacial area. Clinical manifestations are usually symptoms caused by the tumor's invasive compression of surrounding tissues. Aneurysmal Bone Cyst (ABC) is also a benign bone tumor, and it typically occurs in long bones and the spine. Only 2% to 3% of cases occur in the head and neck. Due to the rarity of this combination of clinical cases, clinicians face difficulties in comprehensively understanding this complex lesion. Therefore, a comprehensive review of the clinical manifestations and characteristic imaging findings is necessary for surgeons. CASE PRESENTATIONS: On April 6, 2019, a 13-year-old boy presented with left maxillofacial bulge and pain for 1 month. Magnetic resonance imaging of the paranasal sinuses showed an irregular hive-like mass signal in the left maxillary sinus, and cystic changes with fluid levels were seen in the lesion. After the initial diagnosis of JPOF with primary ABC, we decided to perform a facial mid-facial resection of maxillary sinus tumor to remove the tumor tissue. Finally, after 3 recurrences and 4 operations, there was no tumor recurrence for 20 months after the last operation, and the patient was still under continuous follow-up. CONCLUSIONS: This case provided a reference for the diagnosis and treatment of JPOF combined with ABC. In particular, a new understanding of the association between the two diseases and the management of recurrence were proposed, which had the potential to improve clinical understanding of this complicated condition.


Asunto(s)
Quistes Óseos Aneurismáticos , Fibroma Osificante , Imagen por Resonancia Magnética , Humanos , Quistes Óseos Aneurismáticos/complicaciones , Quistes Óseos Aneurismáticos/diagnóstico por imagen , Quistes Óseos Aneurismáticos/cirugía , Quistes Óseos Aneurismáticos/diagnóstico , Masculino , Adolescente , Fibroma Osificante/cirugía , Fibroma Osificante/complicaciones , Fibroma Osificante/diagnóstico por imagen , Fibroma Osificante/diagnóstico , Neoplasias del Seno Maxilar/complicaciones , Neoplasias del Seno Maxilar/diagnóstico por imagen , Neoplasias del Seno Maxilar/cirugía , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/cirugía , Seno Maxilar/patología
2.
Opt Express ; 31(20): 33064-33076, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859094

RESUMEN

In this paper, we studied a series of high-speed photodetectors (PD) with different super-lattice interlayer periods and the scale of the effective area to examine their communication performance. The mini-PDs are designed with a single 1 mm × 1 mm effective area. The mini-PDs have three different super-lattice (SL) periods in the interlayer: 8, 15, and 32. The micro-PD sample has multiple 50um by 50um photosensitive areas that form a 4 × 4 receiver array, which shares a common N electrode. Its SL period is 26. The experiment shows that mini-PDs have the advantages such as better tolerance to beam spot deviation, larger field of view (FoV), higher responsibility, and wider peak width in spectral response. But micro-LED samples outperform the others in communication capacity and wavelength selectivity. The 8, 15, and 32 SL mini-PD samples achieve 6.6, 7.3, and 8.8 Gb/s data rates, respectively. The micro-PD gains the maximum data rate of 14.38Gb/s without applying waveform level post-equalization, and 15.26Gb/s after using an NN-based post-equalizer. This experiment shows that with proper DSP, GaN-based PD would be suitable for high-speed VLC systems, especially for the short wavelength spectrum in visible light.

3.
Adv Sci (Weinh) ; 10(5): e2205879, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36494090

RESUMEN

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote-sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution-processed mixed tin-lead (MSP) perovskite photodetectors (PPDs) exhibit a trade-off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn2+ oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene-2-carbohydrazide (TAH) molecules and cations/anions in MSP perovskite. The resultant solution-processed rigid mixed Sn-Pb PPD simultaneously achieves high EQE (75.4% at 840 nm), detectivity (1.8 × 1012 Jones at 840 nm), ultrafast response time (trise /tfall = 94 ns/97 ns), and improved stability. This work also highlights the demonstration of the first flexible photodiode using MSP perovskite and FPA strategy with remarkably high EQE (75% at 840 nm), and operational stability. Most importantly, the RWHM is implemented for the first time in the PIN MSP perovskite photodiodes to remotely monitor the heart rate of humans at rest and after-run conditions.

4.
Opt Express ; 31(26): 44315-44327, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178505

RESUMEN

In this paper, we introduce an innovative post-equalization technique leveraging bidirectional reservoir computing (BiRC), and apply it to waveform-to-symbol level equalization for visible light laser communication for the first time. This strategy is more resistant to nonlinearities compared to traditional equalizers like least mean square (LMS) equalizer, while requiring less training time and fewer parameters than neural network (NN) -based equalizers. Through this approach, we successfully conduct a 100-meter transmission of a 32-amplitude phase shift keying (32APSK) signal using a green laser operating at a wavelength of 520 nm. Remarkably, our system achieves a high data rate of 11.2 Gbps, all while maintaining a satisfying bit error rate (BER) below the 7% hard decision forward error correction (HD-FEC) threshold of 3.8E-3.

5.
Sensors (Basel) ; 22(24)2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36560338

RESUMEN

Post-equalization using neural network (NN) is a promising technique that models and offsets the nonlinear distortion in visible light communication (VLC) channels, which is recognized as an essential component in the incoming 6G era. NN post-equalizer is good at modeling complex channel effects without previously knowing the law of physics during the transmission. However, the trained NN might be weak in generalization, and thus consumes considerable computation in retraining new models for different channel conditions. In this paper, we studied transfer learning strategy, growing DNN models from a well-trained 'stem model' instead of exhaustively training multiple models from randomly initialized states. It extracts the main feature of the channel first whose signal power balances the signal-to-noise ratio and the nonlinearity, and later focuses on the detailed difference in other channel conditions. Compared with the exhaustive training strategy, stem-originated DNN models achieve 64% of the working range with five times the training efficiency at most or more than 95% of the working range with 150% higher efficiency. This finding is beneficial to improving the feasibility of DNN application in real-world UVLC systems.


Asunto(s)
Aprendizaje , Luz , Redes Neurales de la Computación , Aprendizaje Automático , Comunicación
6.
Opt Express ; 30(18): 33337-33352, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36242375

RESUMEN

Recently, visible light communication (VLC) has emerged as a promising communication method in 6G. To achieve 6G high-speed transmission, wavelength division multiplexing (WDM) based VLC systems are a highly promising candidate. However, the "yellow and green gap" greatly limits the yellow light efficiency of InGaN-based LEDs and also restricts the transmission rate of yellow LEDs. In addition, pre-equalization and post-equalization also have an important impact on high-speed communication. In this paper, we propose to employ a vertical InGaN-based Si-substrate yellow LED with bit-power loading discrete multitone (DMT) modulation and a novel cascaded pre-equalizer network to achieve a high-speed yellow-light VLC system. The proposed cascaded pre-equalizer network is based on a digital Zobel network and a partial nonlinear pre-equalizer (DZNPN). The microscopic time-domain transient response of the high-speed and large-amplitude signal is also investigated to show a severe impairment. Utilizing the DZNPN cascaded pre-equalizer network based on the third-order Volterra series, a record-breaking data rate of 3.764Gbps over 1.2 m free space and 3.808Gbps over 0.7 m are experimentally demonstrated under the hard decision-forward error correction (HD-FEC) threshold of 3.8 × 10-3. The rate can be improved from 2.818Gbps to 3.764Gbps with 650Mbaud compared to the un-preprocessed signal. This is the highest data rate ever reported for yellow-light VLC systems based on a single LED to the best of our knowledge.

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