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• An in-band OSNR monitoring method for PDM-mQAM signals is proposed. • The proposed monitoring method is modulation-format transparent and cost effective. • The RMSE of OSNR monitoring for PDM-mQAM is within 1 dB at back-to-back transmission. • The RMSE of OSNR monitoring keeps within 1 dB with the interference of 4800-ps/nm CD. In this paper, we propose an in-band optical signal-to-noise ratio (OSNR) monitoring method based on support vector machine (SVM). This method is tailored for the analysis of polarization-division multiplexing (PDM) m-ary quadrature amplitude modulation (m-QAM) signals. OSNR-related features are extracted from the numerical characteristics of Stokes parameters, while modulation-order related features are extracted from the eye diagram of s 1 , which is one of the Stokes parameters. The feasibility of this approach is verified through numerical simulations. The simulation results show that the root mean square error (RMSE) of OSNR monitoring for 28 GBaud PDM-mQAM (m = 4, 8, 16, 32) is within 1 dB over an OSNR range of 15–35 dB at back-to-back transmission. Furthermore, the RMSE of OSNR monitoring keeps within 1 dB under the interference of polarization impairments and up to 4800-ps/nm chromatic dispersion (CD). Since the proposed OSNR monitoring method does not require either additional local laser or sophisticated DSP for signal recovery, it features relatively low cost and complexity with high performances, promising for potential applications in the flexible and elastic optical networks. [ABSTRACT FROM AUTHOR]

Coordinated Multipoint (CoMP) Joint Reception (JR) is a vital technology to mitigate uplink inter-cell interference (ICI) and can be facilitated by the centralized radio access network (C-RAN). In C-RAN architecture, base stations (BSs) are decoupled into the central unit (CU) and the distributed units (DUs). Meanwhile, a fronthaul (FH) is employed to connect CU and DUs. However, FH constructed by the time division multiplexing passive optical network (TDM-PON) significantly affects the performance of JR. The inherent polling mechanism of TDM-PON results in the asynchronous forwarding of JR data, which leads to high JR latency and a large amount of storage consumption. To alleviate the problem, we presented a novel dynamic bandwidth allocation (DBA) scheme, which classifies network data as JR and non-JR data and optimizes the data forwarding order of different types and DUs. A heuristic algorithm called Rearrange Sub-timeslot DBA (RS-DBA) was proposed to implement the DBA scheme. Simulation results indicate the proposed RS-DBA algorithm can reduce the average latency of JR data and storage resources consumption. In addition, the RS-DBA can make a better tradeoff between latency and efficiency. • The uplink joint reception (JR) in mobile fronthaul is discussed. • The latency and storage consumption due to JR is analyzed mathematically. • A heuristic algorithm-assisted dynamic bandwidth allocation scheme is proposed. • The proposal improves the JR performance in terms of latency and storage consumption. • The proposal achieves a better tradeoff between the latency and efficiency of JR. [ABSTRACT FROM AUTHOR]

Emulating the local area network (LAN) has become a vital requirement for the passive optical network (PON). There are many efforts to establish the optical layer LAN (OLAN) in various PONs. However, the existing OLAN schemes generally isolate the LAN function from regular PON, resulting in the rigid allocation of transmission resources. To improve the flexibility of OLAN, this work presents a PON system that can achieve the conversion between PON and LAN. According to different conversions, the system forms three work modes. In addition, a novel bandwidth allocation scheme is proposed for this PON system to determine when to switch its work mode. The proposed bandwidth allocation scheme aims to reuse the idle timeslots due to the half-duplex LAN transmission by sharing the timeslot and wavelength resources between the upstream and LAN transmissions. Simulation results show that the proposed bandwidth allocation scheme can significantly outperform the traditional one in the average latency, network throughput, and load balancing performances. • A local area network scheme based on passive optical network is proposed. • Achieving flexible conversion between local area network and passive optical network. • A bandwidth allocation scheme sharing wavelength and timeslot is proposed. • The flexible system possesses outstanding latency and throughput performance. [ABSTRACT FROM AUTHOR]

Intrauterine adhesion (IUA) is a disease characterized by endometrial fibrosis caused by injury to the endometrium. In the present study, decellularized and lyophilized human amniotic membrane (DL-AM) material was transplanted in a rat model to explore the preventive effect against IUA. A total of 24 Sprague Dawley rats were randomly divided into an IUA (n=12) group and an IUA + DL-AM (n=12) group. To establish the model, the endometrium of the left uterus was scraped, while that of the right uterus was used as a control. In the IUA group, scraped uteri were sutured without any other treatment, whereas DL-AM was transplanted onto the scraped uteri in the IUA + DL-AM group. Uteri were resected for histological and immunohistochemical evaluation at 3, 7, 14 and 28 days after surgery. The results confirmed the development of IUA, which was accompanied by an increase in the rate of fibrotic area. Integral optical density (IOD) values of connective tissue growth factor (CTGF) were elevated in the IUA group, while matrix metalloproteinase-2 (MMP-2) decreased relative to the control group (P<0.05). After DL-AM transplantation, the IOD value of CTGF dropped, while MMP-2 increased compared with the IUA group (P<0.05). However, compared with that in the control group, the IOD value of CTGF was still higher, whereas MMP-2 was still lower in the IUA + DL-AM group (P<0.05). Furthermore, no evidence of endometrial regeneration was detected in both the IUA and IUA + DL-AM groups. Overall, these results indicated that in the rat model of IUA, transplantation of DL-AM had the potential to prevent the formation of fibrosis to a certain extent and may thus be an alternative strategy for managing the condition. [ABSTRACT FROM AUTHOR]