All-optical wavelength-tunable narrow-linewidth fiber laser

Parameter regulations of narrow-linewidth fiber lasers in frequency domain has drawn considerable interests for widespread applications in the light quantum computing, precise coherent detection, and generation of micro-waves. All-optical methods provide compact, precise and fast accesses to achieving these lasers with wavelength-tunability. Here, the optical-thermal effects of graphene is utilized to precisely control operations of free-running lasers with a tuning speed of 140 MHz/ms. Assisted by the single-longitude-mode operation and linewidth suppression of stimulated Brillouin backscattering, we obtain an optical-controllable ~750 Hz fiber laser with a wavelength-tuning range of 3.7 nm

Graph Analysis in Decentralized Online Social Networks with Fine-Grained Privacy Protection

Graph analysts cannot directly obtain the global structure in decentralized social networks, and analyzing such a network requires collecting local views of the social graph from individual users. Since the edges between users may reveal sensitive social interactions in the local view, applying differential privacy in the data collection process is often desirable, which provides strong and rigorous privacy guarantees. In practical decentralized social graphs, different edges have different privacy requirements due to the distinct sensitivity levels. However, the existing differentially private analysis of social graphs provide the same protection for all edges. To address this issue, this work proposes a fine-grained privacy notion as well as novel algorithms for private graph analysis. We first design a fine-grained relationship differential privacy (FGR-DP) notion for social graph analysis, which enforces different protections for the edges with distinct privacy requirements. Then, we design algorithms for triangle counting and k-stars counting, respectively, which can accurately estimate subgraph counts given fine-grained protection for social edges. We also analyze upper bounds on the estimation error, including k-stars and triangle counts, and show their superior performance compared with the state-of-the-arts. Finally, we perform extensive experiments on two real social graph datasets and demonstrate that the proposed mechanisms satisfying FGR-DP have better utility than the state-of-the-art mechanisms due to the finer-grained protection

Optical polarization rogue waves from supercontinuum generation in zero dispersion fiber pumped by dissipative soliton

Optical rogue waves emerge in nonlinear optical systems with extremely large amplitudes, and leave without a trace. In this work, we reveal the emergence of optical polarization rogue waves in supercontinuum generation from a zero-dispersion fiber, pumped by a dissipative soliton laser. Flat spectral broadening is achieved by modulation instability, followed by cascaded four-wave-mixing. In this process, we identify the emergence of optical polarization rogue waves, based on the probability density function of the relative distance among polarization states. Experimental results show that optical polarization rogue waves originate from vector multi-wave-mixing. Besides, we observe double peaks, and even triple peaks in the histogram of the state of polarization. This is a new and intriguing property, never observed so far in optical rogue waves, for example those emerging in the statistics of pulse intensities. Our polarization domain statistical analysis provides a new insight into the still debated topic of the mechanism for rogue wave generation in optical supercontinuum

OR-017 Supplementation of Ala-Gln inhibits protein breakdown of skeletal muscle in rats with altitude training through TNF-α/NF-κB/MuRF1 pathway

Objective Objective: To explore the effects of alanyl-glutamine（Ala-Gln）or glutamine（Gln） supplementation on protein metabolism in rat skeletal muscle during simulated altitude training，and compare the intervention of Gln or Ala-Gln to provide the necessary experimental basis for finding nutritional interventions to inhibit skeletal muscle protein degradation during altitude training. Methods Methods: Forty SD rats aged 6 weeks were randomly divided into normoxic control group（NC group，n=10），hypoxic exercise group（HE group， n=10），hypoxic exercise + glutamine + alanine group（HEG group，n=10）， hypoxic exercise + alanyl glutamine group（HEAG group，n=10）. Rats were subjected to 6 weeks of 13.6% hypoxic exposure and 90% lactic acid threshold intensity weight-bearing swimming（load weight of 2.1% of body weight）exercise training，30 minutes after the end of each training，the mixed solution of Ala and Gln was administered according to the dose of 0.75g/Kg body weight in HEG group，and the solution of Ala-Gln was administered in the HEAG group at a dose of 1.5 g/kg body weight. After 6 weeks，the contents of rat skeletal muscle total protein（Pro），myosin heavy chain（Myo），tumor necrosis factor-α（TNF-α），nuclear transcription factor-κB （NF-κB），NF-κB inhibitory protein α（IkBα），and mRNA expression of muscle atrophy box F gene（MAFbx），muscle ring finger gene 1（MuRF1），and inhibitor of kappa B kinase complex-beta（IKKβ）were measured. Results Results:（1）Compared with NC group，the content of Pro and Myo in skeletal muscle in HE group was significantly decreased（P<0.05，P<0.01），and the mRNA expression of MAFbx and MuRF1 in skeletal muscle was significantly increased（P<0.05，P< 0.01），the levels of TNF-α and NF-κB were significantly increased（P<0.05），the content of IkBα was significantly decreased（P<0.05），and the expression of IKKβ mRNA was significantly increased（P<0.01）. （2）Compared with HE group，the content of Pro and Myo in skeletal muscle in HEG group increased，but there was no significant difference（P>0.05）. The expression of MuRF1 mRNA and the content of TNF-α and NF-κB in skeletal muscle decreased，IkBα content increased，there were no significant difference，but mRNA expression of MAFbx and IKKβ was significantly decreased（P<0.05， P<0.01）. （3）Compared with HE group，the content of Pro and Myo in skeletal muscle in HEAG group increased significantly（P<0.05），mRNA expression of IKKβ，MuRF1 and MAFb（P<0.01）and TNF-α，NF-κB content（P<0.05）in skeletal muscle was significantly decreased，and the IkBα content was significantly increased（P<0.05）. Conclusions Conclusion:（1）Simulated altitude training can activate TNF-α/NF-κB/MuRF1 pathway and enhance the catabolism of skeletal muscle protein，which is one of the important mechanisms for the reduction of skeletal muscle protein content caused by altitude training. （2）Supplementation of Ala-Gln during altitude training can significantly reduce the activation of TNF-α/NF-κB/MuRF1 pathway in skeletal muscle，and reduce the catabolism of skeletal muscle protein during altitude training，which plays a very important role in preventing the loss of skeletal muscle protein caused by altitude training. supplementation of Gln monomer during altitude training has little inhibitory effect on the activation of TNF-α/NF-κB/MuRF1 pathway in skeletal muscle

Experimental revealing of asynchronous transient-soliton buildup dynamics

The buildup process of coherent structures and patterns from the composite balance between conservative and dissipative effects is a universal phenomenon that occurs in various areas of physics, ranging from quantum mechanics to astrophysics. Dissipative solitons are highly coherent solutions of nonlinear wave equations, and provide an excellent research platform for ultrafast transient phenomena. Herein, by taking advantage of the fast detection technique provided by the dispersive Fourier transform, we experimentally observe the spectral broadening and breathing behavior of transient dissipative structures produced asynchronously during the buildup process of dissipative solitons. These observations unveil a novel dynamics of dissipative soliton generation, which is accompanied by energy quantization, self-phase modulation induced spectral broadening, structural dissipative soliton formation, and Raman soliton self-frequency shifting, thus providing a new insight in transient ultrafast laser dynamics

A New Dataset, Poisson GAN and AquaNet for Underwater Object Grabbing

To boost the object grabbing capability of underwater robots for open-sea farming, we propose a new dataset (UDD) consisting of three categories (seacucumber, seaurchin, and scallop) with 2,227 images. To the best of our knowledge, it is the first 4K HD dataset collected in a real open-sea farm. We also propose a novel Poisson-blending Generative Adversarial Network (Poisson GAN) and an efficient object detection network (AquaNet) to address two common issues within related datasets: the class-imbalance problem and the problem of mass small object, respectively. Specifically, Poisson GAN combines Poisson blending into its generator and employs a new loss called Dual Restriction loss (DR loss), which supervises both implicit space features and image-level features during training to generate more realistic images. By utilizing Poisson GAN, objects of minority class like seacucumber or scallop could be added into an image naturally and annotated automatically, which could increase the loss of minority classes during training detectors to eliminate the class-imbalance problem; AquaNet is a high-efficiency detector to address the problem of detecting mass small objects from cloudy underwater pictures. Within it, we design two efficient components: a depth-wise-convolution-based Multi-scale Contextual Features Fusion (MFF) block and a Multi-scale Blursampling (MBP) module to reduce the parameters of the network to 1.3 million. Both two components could provide multi-scale features of small objects under a short backbone configuration without any loss of accuracy. In addition, we construct a large-scale augmented dataset (AUDD) and a pre-training dataset via Poisson GAN from UDD. Extensive experiments show the effectiveness of the proposed Poisson GAN, AquaNet, UDD, AUDD, and pre-training dataset.Comment: 14 pages, 10 figure