Attosecond light sources serve as advanced optical tools that are crucial for investigating electron dynamics at the subfemtosecond scale in quantum systems. However, generating high-intensity isolated X-ray pulses remains a significant scientific challenge. X-ray free-electron lasers (FELs) are advanced light sources based on linear accelerators, capable of generating ultrashort and ultra-intense laser pulses. Enhanced Self-Amplified Spontaneous Emission (ESASE) serves as an effective method for producing ultrashort pulses in FELs by locally enhancing the peak current of electron beams. However, obtaining isolated current spikes has remained a critical challenge for ESASE, which directly determines the signal-to-noise ratio of ultrafast FEL pulses.

In 2015 the United Nations adopted Sustainable Development Goals that are related to social welfare, social equity, and environmental protection. They set a target of reaching these goals by 2030. Since the goals were proposed, China has implemented a wide range of strategies to achieve these goals. A research team has developed a multi-dimensional framework and then used that framework to evaluate Huzhou city’s sustainable development from 2003 to 2022.

The El Niño-Southern Oscillation (ENSO) cycle moves between warmer-than-average Pacific Ocean surface water temperatures during El Niño phases to colder-than-average surface water temperatures during La Niña phases. Scientists have observed that the surface temperatures of water in the central and eastern Pacific affect the number and strength of tropical cyclones (TCs) that develop in the North Atlantic Ocean and the probability those TCs will make landfall. Researchers recently investigated the effects of El Niño and La Niña dissipation events on and factors that contribute to TC development in the North Atlantic Ocean.

This is an initial study to validate central venous pressure (CVP) measurements derived from quantitative compression ultrasound (QCU).