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Energy recovery linac (ERL) holds great promise for generating high repetition-rate and high brightness electron beams. The application of ERL to drive a free-electron laser is currently limited by its low peak current. In this paper, we consider the combination of ERL with the recently proposed angular-dispersion induced microbunching technique to generate fully coherent radiation pulses with high average brightness and tunable pulse length. Start-to-end simulations have been performed based on a low energy ERL (600 MeV) for generating coherent EUV radiation pulses. The results indicate an average brightness over 10 25 phs/s/mm 2 /mrad 2 /0.1%BW and average power of about 100 W at 13.5 nm or 20 W with the spectral resolution of about 0.5 meV with the proposed technique. Further extension of the proposed scheme to shorter wavelength based on an ERL complex is also discussed., (© 2021. The Author(s).)

Overlapping in an optical medium with nonlinear susceptibilities, lightwaves can interact, changing each other's phase, wavelength, waveform shape, or other properties. Such nonlinear optical phenomena, discovered over a half-century ago, have led to a breadth of important applications. Applied to quantum-mechanical signals, however, these phenomena face fundamental challenges that arise from the multimodal nature of the interaction between the electromagnetic fields, such as phase noises and spontaneous Raman scattering. The quantum Zeno blockade allows strong interaction between lightwaves without physical overlap between them, thus offering a viable solution for the aforementioned challenges, as indicated in recent bulk-optics experiments. Here, we report on the observation of quantum Zeno blockade on chip, where a lightwave is modulated by another in a distinct "interaction-free" manner. For quantum applications, we also verify its operations on single-photon signals. Our results promise a scalable platform for overcoming several longstanding challenges in applied nonlinear and quantum optics, enabling manipulation and interaction of quantum signals without decoherence.

Approximately 20% of HER2 positive breast cancer develops disease recurrence after adjuvant trastuzumab treatment. This study aimed to develop a molecular prognostic model that can reliably stratify patients by risk of developing disease recurrence. Using miRNA microarrays, nine miRNAs that differentially expressed between the recurrent and non-recurrent patients were identified. Then, we validated the expression of these miRNAs using qRT-PCR in training set (n = 101), and generated a 2-miRNA (miR-4734 and miR-150-5p) based prognostic signature. The prognostic accuracy of this classifier was further confirmed in an internal testing set (n = 57), and an external independent testing set (n = 53). Besides, by comparing the ROC curves, we found the incorporation of this miRNA based classifier into TNM stage could improve the prognostic performance of TNM system. The results indicated the 2-miRNA based signature was a reliable prognostic biomarker for patients with HER2 positive breast cancer.

There has been considerable professional debate on the association between nausea and vomiting in early pregnancy (NVP) and neural tube defects (NTDs) risk. This study explored the association between NVP and NTDs risk, and the effect of folic acid supplements on the association. A 1:1 matched case-control study was conducted and conditional logistic regression model was used to analyze the associations. The result showed the odds ratio (OR) of severe NVP for NTDs was 2.403 (95%CI 1.437,4.017; P<0.001) and that of moderate NVP was 1.469 (95%CI 1.063,2.031; P = 0.020) compared with light NVP when adjusted by the potential confounders. Stratified by intake of folic acid supplements, the ORs for severe and moderate NVP turned to 2.147 (95%CI 1.140, 4.043; P = 0.018) and 2.055 (95%CI 1.320, 3.199; P = 0.001) in the stratum of non-intake of folic acid supplements while ORs reduced to 1.851 (95%CI 0.729, 4.699; P = 0.195) and 1.003 (95%CI 0.594, 1.694; P = 0.992) in the stratum of intake of folic acid supplements, respectively. We conclude that severe/moderate NVP has an association with the risk of NTDs, which was not found in the group with intake of folic acid supplements. Folic acid supplements should be recommended to use for the prevention of NTDs.