RESUMEN
Realizing vector spatiotemporal solitons that are stable in high dimensions is a long-standing goal in the study of nonlinear optical physics. Here, a scheme is proposed to generate three-dimensional (3D) vector spatiotemporal solitons in a cold atomic system with linear and nonlinear parity-time (PT) potentials by utilizing electromagnetically induced transparency (EIT). We investigate the existence and stability of these vector 3D semilunar solitons (SSs) and vortex solitons (VSs) supported by the linear and nonlinear PT potentials. The results show that these solitons have extremely low generation power and very slow propagation velocity and can stably propagate with constant total energy in this system. The frontal head-on collisions of two vector solitons feature quasi-elastic collisions. The dynamics characteristics of these solitons depend on the linear and nonlinear PT-symmetric potential parameters, in particular, the imaginary part of PT potentials. Our study provides a new route for manipulating high-dimensional nonlinear vector optical signals via the controlled optical linear and nonlinear potentials in cold atomic gases.
RESUMEN
We propose a realistic physical scheme to realize linear Gaussian optical potential with parity-time (PT) symmetry and two dimensional (2D) spacial solitons in a coherent atomic gas. It is shown that the PT-symmetric potential can be created through the spatial modulation of the control and relevant atomic parameters. We find that the Gaussian PT potential parameters, the imaginary part and the width and the position, play crucial roles in the occurrence of the PT phase transition. We demonstrate that the system supports stable 2D dipole solitons and vortex solitons, which can be managed via tuning PT potential. Furthermore, the dynamic characteristics of the symmetric scatter and collision of solitons are shown.
RESUMEN
Background: The enhanced recovery after surgery (ERAS) protocol is widely implemented in surgeries, and this study aims to reveal the characteristics of the 100 most-cited original articles in the field of ERAS research. Methods: The literature was retrieved in the Web of Science database, the 100 most-cited original articles were identified, and their characteristics were analyzed, including the trends of publications and citations; contributions from countries, institutions, and authors; co-cited authors and journals in the references; served surgeries, research endpoints, keywords; and the level of evidence. Results: There was a rising trend in the yearly publications and citations. Denmark and the USA contributed the largest number of highly cited papers. The University of Copenhagen was the most influential institution. Kehlet, Henrik was the most influential author. The British Journal of Surgery was the most often published and cited journal. ERAS protocols were overwhelmingly implemented in colorectal surgeries. The most focused endpoints were "length of stay", "complications", and "readmission". The most frequently used keywords were "fast track", "length of stay", and "laparoscopy". The keyword "enhanced recovery after surgery" burst since 2012. More than half of the highly cited articles presented level IV evidence, but there was no correlation between citations (densities) and the levels of evidence. Conclusions: The highly cited research overwhelming implemented ERAS in colorectal surgeries, the "length of stay" was the most focused element, and Kehlet, Henrik was the most influential researcher. Most of the highly cited ERAS had low levels of evidence, and the total number of citations was not relevant to the level of evidence. Therefore, studies with high levels of evidence are still required in the future.
RESUMEN
Background: Enhanced recovery after surgery (ERAS) protocol has been implemented in surgeries for more than 20 years, this study investigated the global states and hotspots of ERAS research. Methods: Based on the Web of Science database, a bibliometric and visualized study of original ERAS research from 2000 to 2020 was performed, including the trends of publications and citations; distribution of countries, authors, institutions, sources; study design, level of evidence, served surgeries and surgical disciplines. Hotspots were revealed by research interests and keywords. Results: Within the field of original ERAS research, there was a rising trend in annual publications and citations. The USA was the greatest contributor. Kehlet, H, University of Copenhagen were the most influential author and institution, respectively. British Journal of Surgery and Annals of Surgery were the most cited journals. Though there were more prospective designs, more than half of the studies presented level IV evidence and had fewer citations and citation densities compared to that of level II and level III. ERAS protocol was overwhelmingly implemented in colorectal surgeries. Most studies focused on elements of ERAS, the top three research interests were "length of stay," "pain management," and "complications." In recent years, bariatric surgery, compliance with ERAS, and feasibility in the elderly were new hotspots. Conclusion: Revealing the global states and hotspots can help researchers better understand the trends in ERAS research. The USA was the greatest contributor to ERAS research. Kehlet, H, was the most influential author in the field. Bariatric surgery, compliance with ERAS, and feasibility in the elderly represent the new trend of ERAS research. Most of the ERAS research had a low evidence levels, studies with high-level evidence are still required in this field.