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In recent years, 64Cu has received extensive attention along with its growing application in nuclear medicine positron emission tomography (PET) diagnosis. A 64Cu automatic separation apparatus adapted to the Cyclone-30 cyclotron was developed to realize the process automation from target dissolution to nuclide separation and purification for stable 64Cu production at large scale. The apparatus consists of a tank for target dissolution and a system for separation and purification. The operation interface, programming language and specific programming instructions were determined by programming design. Based on the established separation and purification process of 64Cu, the apparatus was designed followed by assembling and testing. After the process parameters of the apparatus were confirmed through a series of conditional experiments, the hot verification experiments at small-scale and three batches of mass production process verification were carried out consecutively, showing that this self-developed apparatus has steady function and can realize distant control. The whole separation process could be finished in 3 h. The radiochemical recovery of 64Cu (after calibration) is greater than 90%, which meets the expected goal of the design. The 64Cu product was tested with over 95% of radiochemical purity, higher than 99.9% of radio nuclidic purity. The contents of impurities such as iron, copper and zinc were less than 1.5 μg/GBq, while cobalt, gold and nickel were less than 0.5 μg/GBq, which meets the requirements of group standard and can be used for preparation of 64Cu radiopharmaceuticals. In conclusion, this self-developed apparatus has low cost and independent intellectual property rights, and its performance and the product quality of 64Cu are comparable to other competitive foreign products. Compared with the manual separation process, the automatic one has significant advantages in terms of the stability of product quality, the process controllability, the time-consuming and the radiation protection of operators. At present, the apparatus has already been used in 64Cu production routinely.

This study investigates field-aligned currents (FACs) during strong magnetic storms in December 2023, analyzing variations in different local times and in the Northern (NH) and Southern Hemispheres (SH). Peak FAC densities were approximately 7.8 times higher than nominal values, with the most equatorward FACs reaching −52° magnetic latitude (MLat). In the summer hemisphere, the daytime FACs were stronger than the nighttime FACs, with the daytime westward Polar Electrojet (PEJ) surpassing nighttime levels. In the winter hemisphere, the nighttime FACs and westward PEJ were stronger than daytime. Generally, the FACs and westward PEJ were stronger in the SH than in the NH across most local time sectors, attributed to greater solar illumination. The NH pre-midnight currents were stronger than for the SH, indicating enhanced substorm currents during winter nights. The nighttime FACs occurred at lower MLat than daytime, with pre-noon FACs at a higher MLat than post-noon. The NH FACs were positioned more equatorward than their SH counterparts. In the NH, the mean FACs correlated most strongly with the merging electric field (Em) at pre-noon, post-noon, and post-midnight and with the SMU (SuperMAG Electrojet Upper Index) at pre-midnight. In the SH, the mean FACs correlated best with the SMU at pre-midnight/pre-noon, with the SML (SuperMAG Electrojet Lower Index) at post-midnight, and Em at post-noon. The mean MLat of the peak FACs show the strongest correlation with Em across most local times and hemispheres. [ABSTRACT FROM AUTHOR]

Simple Summary: In recent years, with global warming and climate change, there have been many cases of successful hornet invasions in some areas. The successful invasion of hornets not only has an impact on local human security and economic activities, but also seriously threatens the bee ecosystem, which has attracted the attention of scientists. Therefore, taking some measures to suppress the foraging and expansion of hornets becomes an important subject. Compared with attractant trapping and poison baits, hornet-tracking technology, which tracks hornets to find their nests, is a more efficient and feasible method. This review paper discusses several common hornet-tracking methods, analyzes the advantages and disadvantages of different methods, and provides a theoretical basis for the development of hornet-tracking technology. Hornet is a general term for insects of the genus Vespa (Hymenoptera: Vespidae). Hornets are predatory insects distributed worldwide. They often appear at apiaries in groups to prey on honey bees, and cause incalculable losses in the honey bee industry. In the face of hornet intrusion, tracking a homing hornet to find its nest is the most efficient way to discover and eliminate the hornets around an apiary. Here, five hornet-tracking methods (hornet tag tracking, triangulation, thermal imaging technology, harmonic radar, and radio telemetry) are reviewed. The advantages, disadvantages and feasibility of each method are discussed to improve the strategies for tracking hornets. Therefore, this review provides ideas for the development of hornet-tracking technology and for improving honey bee protection. [ABSTRACT FROM AUTHOR]

Article in Chinese. [Purpose/significance] This paper discusses standards development for library demand driven acquisitions and introduces the Demand Driven Acquisition of Monographs (NISO DDA), a recommended practice published by the National Information Standards Organization (NISO) in United States.Libraries in China may draw on U.S. experience during their own DDA application and standards development.[Method/process] Through a literature review, this paper discusses the NISO DDA development background, process, key aspects, impact, and the challenges.[Result/conclusion]NISO DDA laid the foundation for the standardization and sustainable development of DDA. It provides guidelines for the standardized adoption and promotion of DDA on the basis of win-win cooperation by various stakeholders such as libraries, publishers, vendors, and aggregators. It has a positive impact on protecting the interests of all stakeholders in the book supply chain. The sustainable development of DDA continues to face challenges; various stakeholders are still actively exploring the ways in which DDA can be further developed.