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A novel seminaphthorhodafluor‐based fluorescent probe was designed and prepared. It exhibited an outstanding off–on fluorescence response (about 45‐fold enhancement) to Cu2+ because the structure changed from a spirocyclic form to a ring‐open state. It showed satisfactory detection performances for Cu2+ with fast response speed, high selectivity and anti‐interference, and a low detection limit (22.9 nM) due to its long emission wavelength and off–on fluorescence response mode. This probe was also satisfactorily applied for the monitoring of Cu2+ in living cells and zebrafish. [ABSTRACT FROM AUTHOR]

CPL‐active flexible materials with high luminescence dissymmetry factor (glum) and luminescent quantum yield are indispensable for 3D displays, wearable devices and so on. Perovskite has drawn much attention due to its fascinating photoelectric properties as well as its abundant applications. However, the existing strategies are inefficient in acquiring perovskite NCs with high glum. In this work, thermoregulated CPL‐active flexible polymer/perovskite hybrid materials with high glum by the creation of chiral photonic bandgap in polymer film with cholesteric domains using toluene as the dielectric media is reported. Based on selective CPL reflection, a satisfied CPL with a maximum glum of 0.6 is achieved. Importantly, the chiral photonic bandgap center of the polymer film can be easily tuned by thermal annealing at different temperatures to adapt various perovskite NCs with full‐spectral emission. The handedness of CPL of hybrid materials can be regulated with and without dielectric media. The presence of the flexible polymer makes hybrid materials a candidate to achieve patterned display applications. Additionally, the polymer/perovskite hybrid materials show excellent stability thanks to the encapsulation effect from polymers. This work provides a facile and general approach to induce adjustable CPL in the whole visible spectrum with high glum and photoluminescence quantum yield (PLQY). [ABSTRACT FROM AUTHOR]

Although immunotherapy of hepatocellular carcinoma using immune checkpoint inhibitors has achieved certain success, only a subset of patients benefits from this therapeutic strategy. The combination of immunostimulatory chemotherapeutics represents a promising strategy to enhance the effectiveness of immunotherapy. However, it is hampered by the poor delivery of conventional chemotherapeutics. Here, it is shown that H‐ferritin nanocages loaded with doxorubicin (DOX@HFn) show potent chemo‐immunotherapy in hepatocellular carcinoma tumor models. DOX@HFn is constructed with uniform size, high stability, favorable drug loading, and intracellular acidity‐driven drug release. The receptor‐mediated targeting of DOX@HFn to liver cancer cells promote cellular uptake and tumor penetration in vitro and in vivo. DOX@HFn triggers immunogenic cell death to tumor cells and promotes the subsequent activation and maturation of dendritic cells. In vivo studies in H22 subcutaneous hepatoma demonstrate that DOX@HFn significantly inhibits the tumor growth with >30% tumors completely eliminated, while alleviating the systemic toxicity of free DOX. DOX@HFn also exhibits robust antitumor immune response and tumoricidal effect in a more aggressive Hepa1‐6 orthotopic liver tumor model, which is confirmed by the in situ magnetic resonance imaging and transcriptome sequencing. This study provides a facile and robust strategy to improve therapeutic efficacy of liver cancer. [ABSTRACT FROM AUTHOR]

Background: It has not been demonstrated that computational fluid dynamics (CFD) can be used to model central venous stenosis (CVS), nor that hemodynamic changes in CVS treated with stent placement can be anticipated. The purpose of this study was to demonstrate the hemodynamic performance of CVS patients treated with stent placement. Methods: Patient‐specific geometric models were constructed using computed tomography images of veins from hemodialysis patients treated with stent placement. CFD simulation based on geometry was performed using ANSYS‐15 to compare pressure quantitatively, wall shear stress (WSS), and flow velocity in the brachial vein before and after stent placement. Results: Following a covered stent placement, the swelling of the left upper extremity was relieved. Prior to stent implantation, the maximum and mean brachial vein wall pressures were 465.2 Pa and 224.609 Pa, respectively. It was determined that the maximum WSS value was 8.449 Pa and that the mean WSS value was 0.743 Pa. The maximum and mean flow velocities were 1.16 and 0.173 m/s, respectively. After stent placement, the maximum wall pressure, maximum WSS, and maximum flow velocity dropped by 59.4%, 71.2%, and 57.8%, respectively. The mean wall pressure, mean WSS, and mean flow rate decreased by 43.5%, 52.7%, and 17.6%, respectively. Conclusion: Hemodynamics of CVS in hemodialysis patients exhibited turbulent, imbalances and disorders, which can be improved by stent placement. [ABSTRACT FROM AUTHOR]

In this study, the first in situ static‐chamber measurements were conducted at coastal Antarctica tundra for CHCl3 fluxes, which showed that CHCl3 was naturally emitted from the Antarctic tundra at 35 ± 27 nmol m−2 d−1, comparable to other reported important natural sources. Significantly, enhanced CHCl3 emission rates (66 ± 20 nmol m−2 d−1) were observed from ornithogenic soil on the island populated with penguins, which was rich in organic matter and halides coming from penguin excrements. It is estimated that Antarctic tundra emits up to 0.1 Gg CHCl3 per year, which is an important source for regional atmospheric CHCl3. Laboratory‐based incubations suggested that organic carbon and chlorine inputs by penguins may stimulate O2 dependent microbial‐mediated CHCl3 emission from the Antarctic tundra, and all tundra soils showed the maximum CHCl3 emission at 4°C. The strength of this CHCl3 source is also expected to change in response to Antarctic warming. Plain Language Summary: Chloroform (CHCl3) is the second‐largest natural carrier of atmospheric chlorine, which can catalyze stratospheric ozone depletion. Natural sources of CHCl3 are believed to predominate over anthropogenic sources, accounting for 50%–90% of global CHCl3 emissions. Among the natural sources, soils are the second‐largest source, after the ocean. This study conducted the first in situ static‐chamber measurements and lab‐based incubations on CHCl3 emissions from Antarctic tundra, and found that it was an important regional source, emitting up to 0.1 Gg CHCl3 each year (<1% of natural terrestrial sources) into the atmosphere. Penguin activities deposited large amounts of excrement in colony tundra and enhanced organic matter and chlorine content in the soil, which promoted the production of CHCl3 mediated by microbial activities. Temperature‐controlled incubations indicated that tundra soils showed the maximum CHCl3 emission at 4°C, and temperature increase and freeze‐thaw cycles might influence annual and seasonal CHCl3 emissions from Antarctic tundra. This study suggested that the strength of CHCl3 source will vary in response to changes in penguin population/colony size, and the extent of Antarctic warming. Key Points: Antarctic tundra is a natural source of CHCl3, emitting up to 0.1 Gg each year into the atmospherePenguins input organic matter and marine halides into the soil through excrement, which facilitates microbial‐mediated CHCl3 productionThe strength of CHCl3 source will vary in response to changes in penguin population/colony size, and the extent of Antarctic warming [ABSTRACT FROM AUTHOR]

The microstructure and corrosion behavior of a high‐strength Al–Zn–Mg–Cu–Mn alloy friction stir welded (FSWed) joint were investigated using scanning electron microscope, transmission electron microscope, open‐circuit potential test, and potentiodynamic polarization. The weld nugget zone and heat‐affected zone (HAZ) of the FSWed joint showed diverse microstructural characteristics including micron‐scale intermetallic particles and nanoscale precipitates, leading to different localized corrosion sensitivities. The results of electrochemical tests confirmed the regional difference of corrosion in FSWed joints. Detailed research on the corrosion process revealed that micron‐scale Al(Fe,Mn,Si) particles promoted the dissolution of the vicinal matrix to induce pitting corrosion. The directionally distributed intermetallic particles and grain boundary precipitates in HAZ conduced to the development of intergranular microcracks into exfoliation. The matrix precipitates affected the localized corrosion tendency due to regional variation of the redissolution degree. [ABSTRACT FROM AUTHOR]

Chiral quasi‐2D perovskite single crystals (SCs) were investigated for their circular polarized light (CPL) detecting capability. Quasi‐2D chiral perovskites, [(R)‐β‐MPA]2MAPb2I7 ((R)‐β‐MPA=(R)‐(+)‐β‐methylphenethylamine, MA=methylammonium), have intrinsic chirality and the capability to distinguish different polarization states of CPL photons. Corresponding quasi‐2D SCs CPL photodetector exhibit excellent detection performance. In particular, our device responsivity is almost one order of magnitude higher than the reported 2D perovskite CPL detectors to date. The crystallization dynamics of the film were modulated to facilitate its carrier transport. Parallel oriented perovskite films with a homogeneous energy landscape is crucial to maximize the carrier collection efficiency. The photodetector also exhibits superior mechanical flexibility and durability, representing a promising candidate for sensitive and robust CPL photodetectors. [ABSTRACT FROM AUTHOR]

Abstract: All‐inorganic cesium lead halide perovskite nanocrystals have emerged as attractive optoelectronic nanomaterials due to their stabilities and highly efficient photoluminescence. High‐sensitivity photodetection covering a large spectral range from ultraviolet to near‐infrared is dominated by phototransistors. To overcome existing limitations in sensitivity and cost of state‐of‐the‐art systems, new‐style device structures and composite material systems are needed with low‐cost fabrication and high performance. Here, field‐effect phototransistors (FEpTs) based on CsPbBr3–PbS colloidal quantum dot heterostructure dominate to obtain a wide response spectral range and high performance. The large spectral detection spectrum is from 400 to 1500 nm similar to PbS quantum dots' response. It is worth mentioning that the device shows responsivity up to 4.5 × 105 A W−1, which is three orders of magnitude higher than the counterpart of individual material‐based devices. Furthermore, other high performance of hybrid CsPbBr3–PbS FEpTs including a short photoresponse time (less than 10 ms) is ascribed to the assistance of heterojunction on the transfer of photoexcitons. The solution‐based fabrication process and excellent device performance strongly underscore CsPbBr3–PbS quantum dot as a promising material for future photoelectronic applications. [ABSTRACT FROM AUTHOR]

High-energy ionizing radiation is widely used in medical diagnosis and cancer radiation therapy. However, high-energy radiation can also impose significant damages in healthy tissues during medical treatments via direct DNA damages and indirect damages from production of reactive oxygen species (ROS). Therefore, it is urgent to develop highly effective radioprotectants with low toxicities that can meet the increasing needs for alleviating the adverse effects from cancer radiation therapy and nuclear emergency. In this work, strongly catalytic ultrasmall (sub-5 nm) cysteine-protected WSe2 dots are employed to protect healthy tissues against radiation via diminishing radiation-induced free radicals. The WSe2 dots with high surface activities can recover radiation-induced DNA damages and eliminate the excessive ROS generated from radiation. In vivo experiments confirm that the survival rate of mice treated with WSe2 dots is significantly elevated with radiation damages postponed under exposure to high-dose ionizing radiation. Furthermore, the free radicals in major organs and hematological system can be appreciably omitted, suggesting their unique role as free radical scavengers. These WSe2 dots in ultrasmall size show rapid renal clearance of ≈74% injection dose via urine excretion in 24 h and do not cause any apparent toxicity in vivo for up to 30 d. [ABSTRACT FROM AUTHOR]

A photoelectrochemical (PEC) cell for water splitting comprises hematite (α-Fe2O3) nanowire arrays covered by nickel oxide (NiO) nanosheets. The cell has increased efficiency because during photoelectrical catalysis, the NiO nanosheets function as proton reduction sites and make a major contribution to water oxidation. According to experimental data the photocurrent of NiO@α-Fe2O3 is enhanced by 43.5 % compared to pristine hematite. The current density of pristine hematite is 2.3 μA cm−2 while that of NiO@α-Fe2O3 is 3.3 μA cm−2 at 1.23 V vs. RHE (under AM 1.5 solar irradiance, in NaOH solution). [ABSTRACT FROM AUTHOR]

Electromagnetic metasurfaces are artificial 2D structures with sub‐wavelength size and have achieved a variety of functions. Coding metasurfaces or programmable metasurfaces are special phase‐manipulation type metasurfaces, which can be used for dynamic electromagnetic modulation and information processing in microwave band. However, programmable or tunable coding metasurfaces in terahertz band are still rare. All‐optical switchable coding metasurfaces based on vanadium dioxide (VO2) hybrid resonators are proposed for dynamic modulation of terahertz waves. The C‐shaped metal–VO2 hybrid resonators are switched from anisotropic structures to quasi‐isotropic ones due to insulator–metal transition of VO2, resulting in great attenuation of conversion efficiency for linearly polarized waves and Pancharatnam–Berry phase for circularly polarized waves. Based on this principle, several coding metasurfaces are shown for efficient and simultaneous switching of wavefront and polarization state of terahertz beams, including linearly and circularly polarized waves. It is worth mentioning that a new method for switchable shared‐aperture metasurfaces is also proposed, in which only a part of the unit cells are integrated with VO2 and tunable. This new scheme promotes the applications of terahertz coding metasurfaces such as high‐speed terahertz communication. [ABSTRACT FROM AUTHOR]