Associations of metabolic dysfunction-associated fatty liver disease and hepatic fibrosis with bone mineral density and risk of osteopenia/osteoporosis in T2DM patients

BackgroundExisting evidence on the associations of liver steatosis and fibrosis with bone mineral density (BMD) and risk of osteopenia/osteoporosis was limited with conflicting results. We aimed to evaluate the associations of metabolic dysfunction-associated fatty liver disease (MAFLD) and hepatic fibrosis with BMD and risk of osteopenia/osteoporosis in type 2 diabetes mellitus (T2DM) patients.MethodsBaseline information of an ongoing cohort of 249 T2DM patients in Xiamen, China was analyzed. MAFLD was defined as the presence of hepatic steatosis [diagnosed by either hepatic ultrasonography scanning or fatty liver index (FLI) score >60] for T2DM patients. BMD was measured using dual-energy x-ray absorptiometry at total lumbar (L2–4), femur neck (FN), and total hip (TH) and was categorized as normal (T ≥ −1.0), osteopenia (−2.5 < T < −1.0), or osteoporosis (T ≤ −2.5) according to its minimum T-score.ResultsAmong the 249 T2DM patients, prevalence rates of MAFLD, osteopenia, and osteoporosis were 57.8%, 50.6%, and 17.7%, respectively. Patients with MAFLD had significantly higher BMD T-scores of L2–4, FN, and TH and the minimum as well as lower prevalence of osteoporosis than patients without MAFLD. Hepatic steatosis indices, including FLI score, fatty liver (FLI ≥ 60 or hepatic ultrasonography scanning), and MAFLD, were significantly and positively associated with all T-scores, while hepatic fibrosis index and FIB-4 score, but not NAFLD fibrosis score (NFS), were negatively associated with all T-scores. MAFLD was significantly associated with the decreased risk of osteopenia/osteoporosis and osteoporosis with unadjusted odds ratios (ORs) (95% CI) of 0.565 (0.324–0.987) and 0.434 (0.224–0.843) (both p-values < 0.05), respectively. As for liver fibrosis, FIB-4 score, but not NFS, was significantly associated with elevated risk of osteoporosis with an unadjusted OR (95% CI) per SD increase of FIB-4 score of 1.446 (1.080–1.936, p-value = 0.013). Adjusting for potential confounding variables, especially body mass index, in the multivariable regression analyses, all associations of hepatic steatosis and fibrosis indices with BMD and risk of osteopenia/osteoporosis were not statistically significant.ConclusionMAFLD and hepatic fibrosis were not significantly associated with BMD and risk of osteopenia/osteoporosis independent of obesity. Nevertheless, screening and management of MAFLD and osteopenia/osteoporosis were still important for the prevention of fracture in T2DM patients

High-speed optical signal processing for telecom applications

Abstract-We discuss high-speed optical signal processing for telecom applications. We focus on the optical wavelength conversion and self-clocking, respectively. In the optical wavelength conversion, we report 40 Gb/s wavelength conversion that is capable of converting the same wavelength using a single semiconductor optical amplifier. Experimental proofs are presented. In addition, we report a novel self-clocking method based on in-band clock pilot insertion at the transmission data signal. The method provides clock recovery without an ultrafast phase comparator and a phase-locked loop in the receiver. Fast synchronization, low timing jitter and a highly stable recovered clock is demonstrated from 160 Gb/s OTDM data signal after 51-km fiber transmission

Dynamics of soliton explosions in a polarization-multiplexed ultrafast fiber laser

Soliton explosions are among the most striking soliton phenomena in nonlinear dissipative systems. In this regime, quasi-stable solitons suffer abrupt structural collapses and then recover to their original state. Here, we report on the first experimental observation of soliton explosions triggered by vector dissipative soliton collisions in a polarization-multiplexed ultrafast fiber laser. The fiber laser simultaneously generates two orthogonally polarized pulse trains with different repetition rates, which enables periodic soliton collisions in the cavity. Based on the dispersive Fourier transform technique, the spectral dynamics of collision-induced soliton explosions are identified in real time. The corresponding time-domain measurements demonstrate opposite temporal shifts in the two output pulse trains. Numerical simulations validate the experimental observations and give more insights into the physical mechanism for soliton explosions. Our findings can shed new light on the dynamics of soliton explosions

Polarization-Insensitive Phase Modulators Based on an Embedded Silicon-Graphene-Silicon Waveguide

A polarization-insensitive phase modulator concept is presented, based on an embedded silicon-graphene-silicon waveguide. Simulation results show that the effective mode index of both transverse electric (TE) and transverse magnetic (TM) modes in the silicon-graphene-silicon waveguide undergoes almost the same variations under different biases across a broad wavelength range, in which the real-part difference is less than 1.2 × 10−3. Based on that, a polarization-insensitive phase modulator is demonstrated, with a 3-dB modulation bandwidth of 135.6 GHz and a wavelength range of over 500 nm. Moreover, it has a compact size of 60 μm, and a low insertion loss of 2.12 dB. The proposed polarization-insensitive waveguide structure could be also applied to Mach-Zehnder modulators and electro-absorption modulators

Bias-Independent Inter-Modulation Method for Simultaneously Measuring Low-Frequency Modulation and Bias Half-Wave Voltages of Mach-Zehnder Modulators

Abstract A bias-independent inter-modulation method is proposed and demonstrated for measuring low-frequency modulation and bias half-wave voltages of Mach-Zehnder modulators (MZMs). The method consists of simultaneous sinusoidal modulation on the modulation and bias ports of the MZM under test. Sinusoidal-modulated sidebands heterodyne with each other and generate the desired inter-modulation products after photodetection, which allows extracting both the modulation depth and half-wave voltage for the modulation and bias ports of the MZM. Our method is independent of bias voltages of the MZM, which can be canceled out by carefully choosing the sinusoidal-modulation frequencies. Moreover, the proposed method enables the low swing voltage for measuring both the modulation depth and half-wave voltage of MZMs. Experiments indicate that the proposed method features the simple setup and high accuracy for low-frequency response measurement ranging from 1 Hz to 1 MHz

Broadband Signal Digitization Based on Low-Speed Non-Uniform Photonic Sampling

A new non-uniform photonic sampling (NPS) strategy and its special signal reconstruction algorithm are proposed to achieve digital acquisition of broadband periodic signals at a low sampling rate. Compared with the existing schemes, the NPS strategy can largely reduce the sampling number to acquire identical signal information as that obtained by using its equivalent high-speed uniform photonic sampling, which is beneficial for reducing the sampling time and the data volume of the NPS-based analog-to-digital converter (ADC). In addition, the calculation time of the proposed algorithm is millions of times lower than that of the digital alias-free signal processing (DASP) algorithm used before, which benefits from the fast Fourier transform calculation of a one-dimensional data array instead of a two-dimensional data array calculation in the DASP algorithm. A simulation is performed to validate the feasibility of the proposed scheme. In the simulation, a single-channel NPS-based ADC with an average sampling rate of 1 GSa/s is demonstrated by using the proposed NPS strategy and signal reconstruction algorithm. The results indicate the reconstructed signal information for a single-tone microwave signal at 9.9 GHz and a linear frequency modulation signal in the frequency range of 1 GHz to 9 GHz are identical to those obtained by using its equivalent high-speed uniform photonic sampling-based ADC with a sampling rate of 20 GSa/s