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Variation in canopy water content (CWC) that can be detected from microwave remote sensing of vegetation optical depth (VOD) has been proposed as an important measure of vegetation water stress. However, the contribution of leaf surface water (LWs ), arising from dew formation and rainfall interception, to CWC is largely unknown, particularly in tropical forests and other high-humidity ecosystems. We compared VOD data from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) and CWC predicted by a plant hydrodynamics model at four tropical sites in Brazil spanning a rainfall gradient. We assessed how LWs influenced the relationship between VOD and CWC. The analysis indicates that while CWC is strongly correlated with VOD (R2  = 0.62 across all sites), LWs accounts for 61-76% of the diurnal variation in CWC despite being < 10% of CWC. Ignoring LWs weakens the near-linear relationship between CWC and VOD and reduces the consistency in diurnal variation. The contribution of LWs to CWC variation, however, decreases at longer, seasonal to inter-annual, time scales. Our results demonstrate that diurnal patterns of dew formation and rainfall interception can be an important driver of diurnal variation in CWC and VOD over tropical ecosystems and therefore should be accounted for when inferring plant diurnal water stress from VOD measurements.

Double-atom catalysts (DACs) for harmful nitrate (NO3−) electroreduction to valuable ammonia (eNO3RR) is attractive for both environmental remediation and energy transformation. However, the limited metal loading in most DACs largely hinders their applications in practical catalytic applications. Therefore, exploring ultrahigh-density (UHD) DACs with abundant active metal centers and excellent eNO3RR activity is highly desired under the site-distance effect. Herein, starting from the experimental M2N6 motif deposited on graphene, we firstly screened the low-density (LD) Mn2N6 and Fe2N6 DACs with high eNO3RR activity and then established an appropriate activity descriptor for the LD–DAC system. By utilizing this descriptor, the corresponding Mn2N6 and Fe2N6 UHD–DACs with dynamic, thermal, thermodynamic, and electrochemical stabilities, are identified to locate at the peak of activity volcano, exhibiting rather-low limiting potentials of −0.25 and −0.38 V, respectively. Further analysis in term of spin state and orbital interaction, confirms that the electronic state effect similar to that of LD–DACs enable the excellent eNO3RR activity to be maintained in the UHD–DACs. These findings highlight the promising application of Mn2N6 and Fe2N6 UHD–DACs in nitrate electroreduction for NH3 production and provide impetus for further experimental exploration of ultrahigh-density DACs based on their intrinsic electronic states. [ABSTRACT FROM AUTHOR]

Going through three important iterations, semiconductor material systems have been widely used in important fields such as microelectronics, communications, artificial intelligence, and carbon neutrality. With the rapid development of technologies, the research on a new generation of high-performance semiconductor materials and devices has become the focus of international advanced technology. As one of the most promising fourth-generation semiconductor material, antimonide semiconductor materials have unique advantages and broad application prospects in developing next-generation high-performance, small-volume, low-power, and low-cost infrared optoelectronic devices. In this paper, the development process and research status of antimonide semiconductor lasers at home and abroad were reviewed, the key issues such as design of device structure, material epitaxial growth, mode selection and wavelength expansion were analyzed, high-performance antimonide quantum well lasers have been grown by molecular beam epitaxy technology. The design scheme and key technology for realizing high-power, single-mode and high-beam quality antimonide lasers were emphasized, and the research prospect of single-mode antimonide lasers with excellent characteristics such as low cost, high yield and high power was predicted. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) presents as a condition marked by a sudden and rapid decrease in kidney function over a short timeframe, resulting from diverse causes. As a transcription factor, PR domain‐containing 16 (PRDM16), has recently been implicated in brown fat biogenesis and heart diseases. Our recent works indicated that PRDM16 could suppress the occurrence of renal interstitial fibrosis in diabetic kidney disorder. Nonetheless, the effect and regulatory mechanism of PRDM16 in AKI remain elusive. Our study demonstrated that PRDM16 inhibited apoptosis induced by ischemic/reperfusion (I/R) in BUMPT (Boston University mouse kidney proximal tubular) cells and HK‐2(Human Kidney‐2) cells. Mechanistically, PRDM16 not only bound to the promoter region of S100 Calcium Binding Protein A6 (S100A6)and upregulated its expression but also interacted with its amino acids 945–949, 957–960, and 981–984 to suppress the p38MAPK and JNK axes via inhibition of PKC‐η activity and mitochondrial reactive oxygen species (ROS) production. Furthermore, cisplatin‐ and I/R‐stimulated AKI progression were ameliorated in PRDM16 proximal‐tubule‐specific knockin mice, whereas exacerbated in PRDM16 knockout proximal‐tubule‐specific mice). Moreover, we observed that formononetin ameliorated I/R‐ and cisplatin‐triggered AKI progression in mice. Taken together, these findings reveal a novel self‐protective mechanism in AKI, whereby PRDM16 regulates the S100A6/PKC‐η/ROS/p38MAPK and JNK pathways to inhibit AKI progression. [ABSTRACT FROM AUTHOR]

High-performance p-B-n infrared photodetectors based on In 0.53 Ga 0.47 As / Ga 0.51 As 0.49 Sb type-II superlattices with an Al 0.85 Ga 0.15 AsSb barrier on an InP substrate have been demonstrated. These photodetectors exhibit 50% and 100% cutoff wavelengths of ∼ 2.1 μm and ∼ 2.6 μm, respectively. At a bias voltage of −100 mV bias voltage, the device exhibits a peak responsivity of 0.618 A/W at 2.1 μm, corresponding to a quantum efficiency of 36.5%. The device exhibits a saturated dark current shot noise limited specific detectivity (D*) of 4.12 × 10 10 cm · Hz 1 / 2 / W (at a peak responsivity of 2.1 μm) under −100 mV applied bias at 300 K. [ABSTRACT FROM AUTHOR]

Soils contaminated with multiple heavy metals pose a significant threat to human health and ecosystem functionality. Following a "treat pollution with waste" strategy, we synthesized Mg‐Fe‐Al ternary layered double hydroxides (LDHs) from waste Bayer red mud for the remediation of heavy metal contaminated soils. Characterization using XRD, FTIR, SEM and EDS methods revealed a characteristic layered structure rich in functional groups, offering reaction sites for heavy metal passivation. Passivation experiments showed that the application of Mg‐Fe‐Al LDHs (2.5 wt.%) reduced the availability of Pb (29.7%), Cd (64.1%) and Cu (66.0%) in contaminated soil from a sulphide iron ore area in southern Sichuan Province. Simulated acid rain experiments showed leachate concentrations of Pb, Cd, and Cu reduced by 43.3%, 72.7% and 42.4%, respectively. This work provides a reference for the development of high‐performance and environmentally friendly adsorption‐stabilizing materials for green remediation. [ABSTRACT FROM AUTHOR]