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1.
Micromachines (Basel) ; 15(5)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38793166

RESUMO

Combined in-band full duplex-multiple input multiple output (IBFD-MIMO) technology can significantly improve spectrum efficiency and data throughput, and has broad application prospects in communications, radar, the Internet of Things (IoT), and other fields. Targeting the self-interference (SI) issue in microwave photonic-based IBFD-MIMO communication systems, a microwave photonic self-interference cancellation (SIC) method applied to the narrowband 2 × 2 IBFD-MIMO communication system was proposed, simulated, and analyzed. An interleaver was used to construct a polarization multiplexing dual optical frequency comb with a frequency shifting effect, generating a dual-channel reference interference signal. The programmable spectrum processor was employed for filtering, attenuation, and phase-shifting operations, ensuring amplitude and phase matching to eliminate the two self-interference (SI) signals. The simulation results show that the single-frequency SIC depth exceeds 45.8 dB, and the narrowband SIC depth under 30 MHz bandwidth exceeds 32.7 dB. After SIC, the desired signal, employing a 4QAM modulation format, can be demodulated with an error vector magnitude (EVM) as low as 4.7%. Additionally, further channel expansion and system performance optimization are prospected.

2.
Opt Express ; 31(4): 5314-5333, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823815

RESUMO

Microwave photonic mixing can realize the frequency conversion of microwave signals in the optical domain, breaking through the bandwidth bottleneck and electromagnetic interference problems of traditional microwave mixing methods. In the background of the hybrid macro-micro cellular system, a wideband, large dynamic range and reconfigurable microwave photonic mixer is proposed, theoretically analyzed and experimentally demonstrated in this paper. By adjusting the modulator bias voltages and matching the proper digital domain operations, a microwave photonic mixer with reconfigurable functions including single-ended dispersion immune mixing, I/Q frequency down-conversion, image rejection mixing, and double-balanced mixing are realized, respectively. Meanwhile, optimizing the electrical attenuator using convex optimization can suppress the third-order intermodulation distortion (IMD3), maximize the conversion gain, and finally improve the spur-free dynamic range (SFDR). Experimental results show that the proposed scheme can be operated with a frequency from 5 to 20 GHz, and the SFDR can achieve 118.3 dB·Hz4/5. Over the whole frequency range, I/Q frequency down-conversion can be well conducted with an amplitude imbalance below 0.7 dB and a phase imbalance below ±0.7°. After an I/Q imbalance compensation algorithm, the image rejection ratio of over 60 dB is produced. The power fading caused by fiber dispersion is also compensated successfully. For a vector signal with 16 quadrature amplitude modulation, the best error vector magnitude (EVM) reaches 3.4%.

3.
Open Med (Wars) ; 15(1): 540-544, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33336009

RESUMO

Primary secondary tumor increased recently with the use of immunomodulatory drugs in patients with multiple myeloma (MM). However, MM with prior diagnosis of primary secondary tumor is relatively rare. In this study, we reported an MM patient with prior diagnosis of rectal cancer. In brief, an 85-year-old man was first diagnosed with rectal cancer. Given the age, heart failure and small-cell hypochromic anemia (hemoglobin level: 54 g/L), rectal cancer resection was not advised and symptomatic treatments were performed (including sufficient iron supplementation). Eight months later, the patient was diagnosed with MM due to worsening anemia. Anemia and heart failure were corrected after three cycles of treatment with thalidomide, dexamethasone and capecitabine. Radical resection of rectal carcinoma (Hartmann) was finally performed due to acute abdominal distension. Meanwhile, RR interval prolongation (longest interval >5.0 s) and atrial fibrillation occurred in the fifth cycle treatment. One month after discontinuation of thalidomide, RR interval returned to normal range, while atrial fibrillation developed into persistent atrial fibrillation.

5.
Leuk Lymphoma ; 60(7): 1731-1739, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616472

RESUMO

We retrospectively studied 133 myelodysplastic syndrome patients receiving decitabine during January 2009 and September 2017. The dose of 15 mg/m2/d (n = 83) and 20 mg/m2/d (n = 50) had comparable overall response rates (ORR) (51.8% vs. 52.00%) and complete remission rate (CRR) (15.66% vs. 22.00%). The 15 mg/m2/d group had a lower incidence of grade 3/4 neutropenia (60.24% vs. 88.00%, p < .05) and thrombocytopenia (65.06% vs. 88.00%, p < .05). The 15 mg/m2/d group had a longer median overall survival (OS) (21.60 months vs. 15.23 months, p = .02). The same results were seen in refractory anemia with excess blasts (RAEB) patients: The 15 mg/m2/d group also had comparable ORR, CRR, decreased hematological toxicities and longer OS. Further analysis suggested that survival benefit of 15 mg/m2/d group was mainly in those patients with lower risk stratification. In conclusion, 15 mg/m2/d decitabine is associated with a lower incidence of hematological toxicities and longer OS and may be more suitable for patients with relatively lower risk.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Decitabina/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Idoso , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
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