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Supplemental Digital Content is available in the text, Background: Cardiac masses are rare, but lead to high risk of stroke and death. Because of the different treatment methods, it is significant for clinicians to differentiate the nature of masses. Cardiac magnetic resonance (CMR) imaging has high intrinsic soft-tissue contrast and high spatial and temporal resolution and can provide evidence for differential diagnosis of cardiac masses. However, there is no evidence-based conclusion as to its accuracy. Therefore, the purpose of our study is to perform a systematic review on this issue and provide useful information for clinical diagnosis and treatment. Methods: We will perform a systematic search in EMBASE, Cochrane Library, PubMed and Web of Science for diagnostic studies using CMR to detect cardiac masses from inception to October, 2019. Two authors will independently screen titles and abstracts for relevance, review full texts for inclusion and conduct detail data extraction. The methodological quality will be assessed using the QUADAS-2 tool. If pooling is possible, we will use bivariate model for diagnostic meta-analysis to estimate summary sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of CMR, as well as different sequences of CMR. Estimates of sensitivity and specificity from each study will be plotted in summary receive operating curve space and forest plots will be constructed for visual examination of variation in test accuracy. If enough studies are available, we will conduct sensitivity analysis and subgroup analysis. Results: The results of this systematic review and meta-analysis will be published in a peer-reviewed journal. Conclusion: To our knowledge, this will be the first systematic review on the accuracy of CMR in the differential diagnosis of cardiac masses. This study will provide evidence and data to form a comprehensive understanding of the clinical value of CMR for cardiac masses patients. Ethics and dissemination: Ethics approval and patient consent are not required, as this study is a systematic review. PROSPERO registration number: CRD42019137800.

Periodically spaced amplifiers along a transoceanic fiber links provide the phas e_matching condition for four_wave_mixing because of Kerr nonlinearity. Both ana lytic method and numerical method are used to study the cross_phase modulational sideband instability in fiber links with periodical lump amplifiers. In the ana lytic method, the gain of sideband instability is obtained. In the numerical met hod, by use of split_step Fourier transform method, the frequency spectra of out put optical pulses are obtained in normal and anomalous fiber links, and there a re sidebands in the spectrum configuration. By comparison of the results from tw o the methods, they are constant with each other.