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Flexible strain sensors based on conductive hydrogels show great potential in wearable devices, electronic skins, and bioelectronics. However, hydrogels inevitably exhibit poor durability for long‐term usage due to the water loss by evaporation. Herein, an external packaging strategy is demonstrated for fabricating sandwich‐like packaged hydrogel strain sensors (PHSSs) through the combination of conductive hydrogel injection and subsequent packaging via a photopolymerization procedure. The as‐prepared PHSS consists of two functional parts, internal hydrogel conducting wires exhibiting excellent linear strain sensing performance as sensing element and an external packaging hydrogel layer with good transparency and conformal adhesion to human skin. Thanks to these intriguing merits, the PHSS possesses the capability to detect both the large‐scale and subtle human motions precisely. Particularly, compared to conventional naked hydrogel strain sensors, the lifespan of PHSS is proved to be remarkably enlarged benefiting from the protective effect of external packaging layer towards the embedded hydrogel sensing element. Besides, the swelling property of external packaging layer even after severe dehydration enables the sensor to be reusable. This work provides a new approach for the fabrication of flexible strain sensors with enhanced lifespan and good reusability. [ABSTRACT FROM AUTHOR]

In clinical pharmacology, the free drug hypothesis has been widely applied in the interpretation of the relationship between pharmacokinetics and pharmacodynamics (PK/PD). The free drug hypothesis assumes that the unbound drug concentration in blood is the same as that in the site of action at steady state. The objective of this study is to demonstrate whether the free drug hypothesis is universally applicable for all drugs. The unbound concentrations of the 18 compounds in blood and in brain interstitial fluids (ISF) at steady state following constant intravenous infusion were simultaneously monitored up to 6 hours via in vivo microdialysis technique. Based on the permeability and efflux ratio (ER), the test compounds can be divided into two classes. Class I includes the compounds with good membrane permeability that are not substrates of efflux transporters (eg, P‐gp, BCRP, and MRPs), whereas Class II includes the compounds that are substrates of efflux transporters. The steady‐state unbound drug concentrations in blood, brain, and CSF are quantitatively very similar for Class I compounds, whereas the steady‐state unbound concentrations in the brain and CSF are significantly lower than those in blood for Class II compounds. These results strongly suggest that the free drug hypothesis is not universal for all drugs but is only applicable for drugs with good permeability that are not substrates of efflux transporters. [ABSTRACT FROM AUTHOR]

Kaolin, a natural and inexpensive clay mineral, is ubiquitous in soil, dirt, and airborne particles. Amongst four commonly available clay minerals, kaolin, as a result of its layered structure, is the most efficient natural gaseous Hg adsorbent to date (Langmuir maximum adsorption capacity Qm=574.08 μg g−1 and Freundlich Qm=756.49 μg g−1). The Hg uptake proceeds by homogeneous monolayer and heterogeneous processes. Hg physisorption on kaolin occurs in the dark, yet the adsorption rate is enhanced upon irradiation. The effects of several metal complexes, salts, halides and solvents on the Hg uptake were examined. The addition of CuCl2 particles leads to a significant enhancement of the Hg uptake capacity (>30 times) within second timescales and without irradiation. The physisorption with kaolin is switched to chemisorption upon the addition of CuCl2 to kaolin. This process is entirely reversible upon the addition of Zn/Sn granules at room temperature without any added energy. However, the investment of a small amount of renewable energy can speed up the process. This technology demonstrates the facile and efficient capture and recycling of elemental Hg0 from air. A wide range of metal particles and diverse physicochemical processes, which include the microphysics of nucleation, are herein examined to explore the potential reaction mechanism by using a suite of complementary analytical techniques. These new mechanistic insights open a new era of energy‐neutral environmental remediation based on natural soil/airborne particles. [ABSTRACT FROM AUTHOR]

The resonant frequency of LLC resonant converter has a wide range of switching frequency due to load changes and it easily enters high frequency band during light load and no-load conditions. Therefore, this study proposes a self-adaptation load change control strategy. According to different load conditions, the converter automatically selects the best control mode among three control methods, which are pulse-frequency modulation, symmetrical pulse-width modulation and burst. By fully utilising the characteristics of the load-independent point in the gain curve and the relationship between the resonant current and the load, the switching conditions between the control strategies are further designed and optimised. In addition, based on the adaptive load change control strategy, the design value of k (the ratio of the excitation inductor to the resonant inductance of the transformer) is increased, which solved the disadvantage of large change of the switch range. And the converter can not only effectively control the output voltage during light load, but also works in the soft-switching state, which can improve the working efficiency of the converter to above 91%. Finally, taking a three-phase staggered parallel LLC resonant converter as the research object, an experimental prototype was developed based on SiC devices to verify the correctness and rationality of the proposed control strategy. [ABSTRACT FROM AUTHOR]