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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.

Using Challenging Minisatellite Payload (CHAMP) observations, responses of ionospheric radial current (IRC) in F‐layer to sawtooth substorms in different magnetic local times are investigated. The zonal wind effect alone cannot entirely explain the variability of the substorm time disturbance IRC. When substorms commence amid stable southward interplanetary magnetic field (IMF), it induces an eastward (westward) equatorial electric field in the daytime (nighttime). This electric field induces an equatorward (poleward) Hall current at low latitudes, consequently generating an upward (downward) perturbation in IRC. Conversely, substorms with varying IMF Bz, where IMF is southward but with a reduced magnitude or turned north after the onset, induce a westward (eastward) equatorial electric field in the daytime (nighttime). This electric field induces a poleward (equatorward) Hall current at low latitudes, consequently generating a downward (upward) disturbed IRC. Notably, this effect is primarily attributed to the varying IMF Bz rather than solely to substorm onset. Plain Language Summary: Substorms represent intense and dynamic disturbances within the Earth's magnetosphere, characterized by sudden bursts in auroral activity. The interplanetary magnetic field (IMF) stands out as an important factor in triggering substorms. Our work unveils for the first time that substorm accompanied by varying IMF Bz, where IMF is southward but with a reduced magnitude or turned north after the onset, and those during stable southward IMF periods, elicit diametrically contrasting effects on the ionospheric radial current (IRC) across all local time sectors. The IRC assumes a pivotal role in facilitating the energy exchange between the ionospheric E‐F layers, thereby exerting a profound influence on the ionospheric dynamics. Our work underscores a compelling correlation between the disturbed IRC and the penetration of the substorm electric field into the equatorial ionospheric E region under different IMF conditions. The study demonstrates the significant impact of different solar wind IMF conditions on the propagation of energy in Earth's space environment. Key Points: Initial observations of F‐layer radial current responses to substorms under different IMF conditionsSubstorm induces upward (downward) radial currents during the day (night) owing to Hall currents caused by disturbed electric fieldDaytime downward (nighttime upward) radial currents occur only in substorms with varying IMF Bz, due to overshielding electric field [ABSTRACT FROM AUTHOR]

AbstractAnticoagulation treatment for patients with high bleeding risk during hemodialysis is challenging. Contact between the dialysis membrane and the blood leads to protein adsorption and activation of the coagulation cascade reaction. Activated coagulation Factor X (FXa) plays a central role in thrombogenesis, but anticoagulant modification of the dialysis membrane is rarely targeted at FXa. In this study, we constructed an anticoagulant membrane using the polydopamine coating method to graft FXa inhibitors (apixaban and rivaroxaban) on the membrane surface. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used to characterize the membranes. The apixaban- and rivaroxaban-modified membranes showed lower water contact angles, decreased albumin protein adsorption, and suppressed platelet adhesion and activation compared to the unmodified PES membranes. Moreover, the modified membranes prolonged the blood clotting times in both the intrinsic and extrinsic coagulation pathways and inhibited FXa generation and complement activation, which suggested that the modified membrane enhanced biocompatibility and antithrombotic properties through the inhibition of FXa. Targeting FXa to design antithrombotic HD membranes or other blood contact materials might have great application potential. [ABSTRACT FROM AUTHOR]

Digital twin technology significantly enhances construction site management efficiency; however, dynamically reconstructing site activities presents a considerable challenge. This study introduces a methodology that leverages camera data for the 3D reconstruction of construction site activities. The methodology was initiated using 3D scanning to meticulously reconstruct the construction scene and dynamic elements, forming a model base. It further integrates deep learning algorithms to precisely identify static and dynamic elements in obstructed environments. An enhanced semi-global block-matching algorithm was then applied to derive depth information from the imagery, facilitating accurate element localization. Finally, a near-real-time projection method was introduced that utilizes the spatial relationships among elements to dynamically incorporate models into a 3D base, enabling a multi-perspective view of site activities. Validated by simulated construction site experiments, this methodology showcased an impressive reconstruction accuracy reaching up to 95%, this underscores its significant potential in enhancing the efficiency of creating a dynamic digital twin model. [ABSTRACT FROM AUTHOR]