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Ocean observational gridded products are vital for climate monitoring, ocean and climate research, model evaluation, and supporting climate mitigation and adaptation measures. This paper describes the 4th version of the Institute of Atmospheric Physics (IAPv4) ocean temperature and ocean heat content (OHC) objective analysis product. It accounts for recent developments in quality control (QC) procedures, climatology, bias correction, vertical and horizontal interpolation, and mapping and is available for the upper 6000 m (119 levels) since 1940 (more reliable after ∼ 1957) for monthly and 1°×1° temporal and spatial resolutions. IAPv4 is compared with the previous version, IAPv3, and with the other data products, sea surface temperatures (SSTs), and satellite observations. It has a slightly stronger long-term upper 2000 m OHC increase than IAPv3 for 1955–2023, mainly because of newly developed bias corrections. The IAPv4 0–2000 m OHC trend is also higher during 2005–2023 than IAPv3, mainly because of the QC process update. The uppermost level of IAPv4 is consistent with independent SST datasets. The month-to-month OHC variability for IAPv4 is desirably less than IAPv3 and the other OHC products investigated in this study, the trend of ocean warming rate (i.e., warming acceleration) is more consistent with the net energy imbalance at the top of the atmosphere than IAPv3, and the sea level budget can be closed within uncertainty. The gridded product is freely accessible at 10.12157/IOCAS.20240117.002 for temperature data (Cheng et al., 2024a) and at 10.12157/IOCAS.20240117.001 for ocean heat content data (Cheng et al., 2024b). [ABSTRACT FROM AUTHOR]

The burgeoning field of semiconductor‐mediated organic conversion is of paramount significance, with zinc indium sulfide (ZnIn2S4) emerging as a standout candidate owing to its benign nature, optimal bandgap, extensive light absorption spectrum, remarkable physicochemical properties, and straightforward synthesis. This review examines the latest breakthroughs and the trajectory of ZnIn2S4‐based photocatalysts in the realm of selective organic transformation. We start with a distinct overview of the intrinsic physical attributes of ZnIn2S4 and the underlying mechanisms driving its efficacy in photocatalytic organic transformations. Subsequently, the preparation methods of ZnIn2S4 are summarized. The main focus is the state‐of‐the‐art photocatalytic application of various ZnIn2S4‐based photocatalysts, such as redox reactions, the construction of C−C, C−S and S−S bonds, and the cleavage of C−O, C−C, and C=C bonds. In the conclusion part, we provide our perspectives on the prospective advancements and the remaining challenges that lie ahead in the optimization of ZnIn2S4‐based photocatalysts, with the ultimate goal of enhancing their efficacy for a diverse array of photosynthetic applications. It is anticipated to inspire the strategic engineering of ZnIn2S4 and other semiconductor‐based photocatalysts for various artificial photosynthesis reactions. [ABSTRACT FROM AUTHOR]

As a natural satellite of the Earth, the moon is a prime target for planetary remote sensing exploration. However, lunar polarization studies are not popular in the planetary science community. Polarimetry of the lunar surface had not been carried out from a spacecraft until the Korean lunar exploration program was initiated. In previous polarization observations of the moon, images of different polarization states were obtained by a rotating linear polarizer. This method is not well suited for future polarization observations from space-based spacecraft. To this end, we present a new kind of polarized observation of the moon using a division of a focal-plane polarization camera and propose a pipeline on the processing method of the polarization observation of the moon. We obtain a map of the degree of white-light polarization on the nearside of the moon through polarization observation, data processing, and correction. The observation and data processing methods presented in this study have the potential to serve as a reference for analyzing polarization observation data from future orbiting spacecraft. These are expected to lead to new discoveries in the fields of astronomy and planetary science. [ABSTRACT FROM AUTHOR]

A Moon‐based sensor can observe the Earth as a single point and achieve disk‐integrated measurements of outgoing longwave radiation (OLR), which significantly differs from low orbital, geostationary, and Sun–Earth L1 point platforms. In this study, a scheme of determining the disk‐integrated Earth's OLR based on a Moon‐based platform is proposed. The observational solid angle was theoretically derived based on the Earth's ellipsoid model and the disk‐integrated observational anisotropic factor was estimated to eliminate the effects of the Earth's radiant anisotropy. The simulated disk‐integrated Earth's OLR obtained from a Moon‐based platform varies periodically, due to changes in the observation geometry and Earth's scene distribution within the observed Earth's disk. Clouds, meteorological parameters, and the land cover distribution notably affect the disk‐integrated Earth's OLR. By analyzing the disk‐integrated Earth's OLR from a Moon‐based platform, significant variabilities were investigated. Additionally, the Earth's shape and radiant anisotropy that affecting the disk‐integrated Earth's OLR were estimated. In conclusion, a more realistic Earth's shape, the latest version of the angular distribution model (ADM), and accurate land cover and meteorological datasets are needed when determining the disk‐integrated Earth's OLR. It is expected the unique variability captured by this platform and its ability to complement traditional satellite data make it a valuable tool for studying Earth's radiation budget and energy cycle, and contributing to diagnostic of the climate General Circulation Models (GCM) performance. Plain Language Summary: Observing large‐scale geoscience phenomena poses a significant challenge, necessitating observations that guarantee spatial continuity and temporal consistency. Equipping sensors on the lunar surface can observe the whole Earth's disk, which is a feasible way to complement the existing satellites. Determining the disk‐integrated Earth's OLR from a Moon‐based platform helps in exploring its potential for detecting geoscience phenomena at different scales. Our study finds that the Moon‐based disk‐integrated Earth's OLR would provide full coverage of the whole Earth's phase angle during one sidereal month. The day‐night and land‐ocean effects on the Moon‐based disk‐integrated OLR during one sidereal month would provide substantial variability to compare to similarly sampled GCM output comparison that is not available from conventional satellite data. Such these unique variabilities in the Moon‐based disk‐integrated Earth's OLR make the Moon a valuable Earth observation platform for studying Earth's radiation budget and energy cycle, and evaluating the performance of GCMs. Key Points: Disk‐integrated Earth's outgoing longwave radiation are estimated considering Earth's shape and radiant anisotropyOverall understanding of the variability on Moon‐based disk‐integrated Earth's outgoing longwave radiationDiscussing the characteristics of Moon‐based disk‐integrated Earth's outgoing longwave radiation [ABSTRACT FROM AUTHOR]

H2V3O8/GaN n–n heterojunction ultraviolet photodetectors are fabricated via a facile dip-coating method. The Schottky junction between the GaN and H2V3O8 builds a built-in electric field to achieve the self-powered phenomenon. The photodetector presents a high photocurrent (0.23 μA) and a fast response speed (less than 0.3 s) at 0 V bias and under 365 nm light illumination (24.50 mW cm−2). Furthermore, the photocurrent increases steadily as the light intensity increases from 0.53 to 24.50 mW cm−2. The H2V3O8/GaN heterojunction holds great potential to realize high-performance hybrid PDs. [ABSTRACT FROM AUTHOR]

Alnustone, a diarylheptane compound, exhibits potent growth inhibition against hepatocellular carcinoma (HCC) BEL‐7402 cells. However, the underlying mechanisms associated with its anticancer activity remain unknown. In the present study, we evaluated the anticancer effect of alnustone against several human cancers focused on HCC and the possible associated mechanisms. The results showed that alnustone significantly inhibited the growth of several cancer cells by CCK‐8 assay. Alnustone markedly induced apoptosis and decreased mitochondrial membrane potential in BEL‐7402 and HepG2 cells. Alnustone inhibited the expression of proteins related to apoptosis and PI3K/Akt/mTOR/p70S6K pathways and generated ROS production in BEL‐7402 and HepG2 cells. Moreover, N‐acetyl‐L‐cysteine (NAC, a ROS inhibitor) could significantly reverse the effects of alnustone on the growth inhibition of BEL‐7402 and HepG2 cells and the expression of proteins related to apoptosis and PI3K/Akt/mTOR signaling pathway in HepG2 cells. Furthermore, alnustone significantly inhibited tumor growth of HepG2 xenografts, obviously induced apoptosis in the tumor tissues and improved the pathological condition of liver tissues of mice in vivo. The study provides evidence that alnustone is effective against HCC via ROS‐mediated PI3K/Akt/mTOR/p70S6K pathway and the compound has the potential to be developed as a novel anticancer agent for the treatment of HCC clinically. [ABSTRACT FROM AUTHOR]

Due to the almost hemispheric observational scope of the Moon-based Earth observations, the effects of sampling time interval on the image offsets of the observed points are fundamentally different from the cases of traditional satellite-based platforms. Sampling time intervals will affect the offsets in the full-disc image, while the magnitude of the image offsets is dependent on the spatial resolution. Hence, their relationships merit further investigation. To this end, a novel method to determine the image coordinates based on radius-angle pair expression is proposed. The offsets of the observed points between two adjacent samplings can be calculated and the effects of the sampling time interval on the offsets can be analysed. We found that the magnitude of the image offsets in the x-axis direction is approximately two times larger than that in y-axis direction under the same sampling time interval and the effects of the sampling time interval is related to the observed point's latitude. Further, based on the fact that the maximum offsets occur at the Earth's equator, the detailed calculation of the shortest sampling time interval taken to exceed 1-pixel offset corresponding to different spatial resolutions is carried out. The results described herein can provide guidance for designing sensors for Moon-based Earth observations. [ABSTRACT FROM AUTHOR]

The Moon is a potential new platform for Earth observation. The advantages of its large-scale observational scope, long temporal duration, and multi-layer detecting of the Earth will undoubtedly advance our understanding of the Earth system. To carry out the observations from a Moon-based optical sensor, the geolocation error caused by exterior orientation elements need to be investigated. This paper analyses the error effects of exterior orientation elements on geolocation for an optical sensor. To estimate the error, we present a geometric image model and utilise some parameters to measure the image offsets. Through a large number of numerical simulations, the results demonstrate that the image offsets are not obvious influenced by the distance and observation angle at mid-high latitude of the Moon and have linear correlation with the increasing errors of the exterior orientation elements. Further, the relationship between the spatial resolution and errors of exterior orientation elements are revealed. Finally, the error characteristics for Moon-based Earth observation are discussed. It is expected that the conclusion drawn in this paper could support the study of a Moon-based Earth observation optical sensor. [ABSTRACT FROM AUTHOR]

The Moon, Earth's only natural satellite, is a potential new platform for Earth observation. Moreover, with the wide applicability of the angular information from remote sensing data, it has been attracting increasingly more attention. Accordingly, this study focuses on the angular characteristics of Moon-based Earth observations. Using ephemeris DE430 and Earth orientation parameters, the position and attitude of the Sun, Earth, and Moon were obtained and their coordinates normalized to a single framework using coordinate transformations between the related reference systems. Then, an angular geometric model of Moon-based Earth observations was constructed, and the corresponding angular algorithms were presented. The results revealed the angular range and distribution characteristics of Moon-based Earth observations. For every point on the surface of the Earth, the view and solar zenith angles all vary widely, which decreases with increasing latitude. The view and solar zenith angles all vary widely with the largest range of values in the equatorial and polar regions and a smaller range of values in mid-latitudes. Furthermore, the range of solar angles of Moon-based Earth observations is the same as that of all-time solar angles, indicating the potential for monitoring and understanding large-scale geoscientific phenomena using Moon-based Earth observations. [ABSTRACT FROM AUTHOR]