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Existing copyright protection schemes for 3D models of oblique photography predominantly utilize digital watermarking technology, most of which suffer from shortcomings such as the potential false accusation of legitimate users and the inability to effectively trace unauthorized distributors. In response to these challenges, this article proposes a homomorphic encryption domain asymmetric fingerprinting scheme for 3D models of oblique photography. Initially, the fingerprints to be embedded are collaboratively generated by the transacting parties, with the publisher remaining unaware of the user's actual fingerprint. This approach ensures the effective implementation of the asymmetric nature of the fingerprinting scheme. Subsequently, potential geometric and non‐geometric attacks are considered prior to fingerprint embedding. Robustness is enhanced for the proposed solution through relative coordinate transformations and normalization procedures. Ultimately, the embedding and extraction of fingerprints are achieved through the application of an effective bit parity check method, in conjunction with the vertex‐paradigm projection length mapping mechanism and the Paillier homomorphic encryption system, minimizing embedding distortion while ensuring data security. Experimental results demonstrate that the proposed solution exhibits satisfying robustness against common manipulations, such as cropping, simplification, and geometric attacks. Additionally, the scheme effectively safeguards legitimate users from false accusations and accurately traces maliciously authorized users. [ABSTRACT FROM AUTHOR]

Multilayer ceramic actuators find extensive utility in applications requiring precise displacement control or force output, due to their advantages of high precision control, rapid response, low driving voltage, low power consumption, and so on. For practical applications, there is a need for high‐performance multilayer ceramic actuators (MLAs) that combine cost‐effectiveness, efficiency, and temperature stability. In this work, 1.5 mol%Sm‐doped 0.25 Pb(Mg1/3Nb2/3)O3–0.36PbZrO3–0.39PbTiO3 piezoelectric ceramics with PbO–CuO as sintering aid were fabricated. The addition of PbO–CuO significantly reduced the sintering temperature by 300°C, while having minimal impact on the piezoelectric properties. The optimized sintering condition, achieved at a low sintering temperature of 950°C with the introduction of a tiny 0.4 wt% sintering aid, yields impressive piezoelectric strain coefficient d33* = 690 pm/V. This substantiates the viability of employing low‐cost Ag/Pd (90/10) as inner electrode, which can be co‐fired with ceramic layer to fabricate MLA. This innovation enables a remarkable displacement of 1 µm at a low driving voltage of 200 V across a 9‐layers piezoelectric actuator, accompanied by high‐temperature stability, exhibiting <20% variation over the temperature range of 30–250°C. These results underscore a great potential for high‐performance piezoelectric actuators over a broad temperature range. [ABSTRACT FROM AUTHOR]

Vibrio is a salt‐tolerant heterotrophic bacterium that occupies an important ecological niche in marine environments. However, little is known about the contribution of resource diversity to the marine Vibrio diversity and community stability. In this study, we investigated the association among resource diversity, taxonomic diversity, phylogenetic diversity, and community stability of marine Vibrio in the Beibu Gulf. V. campbellii and V. hangzhouensis were the dominant groups in seawater and sediments, respectively, in the Beibu Gulf. Higher alpha diversity was observed in the sediments than in the seawater. Marine Vibrio community assembly was dominated by deterministic processes. Pearson's correlation analysis showed that nitrite (NO2−$$ {\mathrm{NO}}_2^{-} $$‐N), dissolved inorganic nitrogen (DIN), ammonium (NH4+$$ {\mathrm{NH}}_4^{+} $$‐N), and pH were the main factors affecting marine Vibrio community stability in the surface, middle, and bottom layers of seawater and sediment, respectively. Partial least‐squares path models (PLS‐PM) demonstrated that resource diversity, water properties, nutrients, and geographical distance had important impacts on phylogenetic and taxonomic diversity. Regression analysis revealed that the impact of resource diversity on marine Vibrio diversity and community stability varied across different habitats, but loss of Vibrio diversity increases community stability. Overall, this study provided insights into the mechanisms underlying the maintenance of Vibrio diversity and community stability in marine environments. [ABSTRACT FROM AUTHOR]

Alpine shrubland not only has significant ecological function and ecological value, but also is a grazing land for Tibetan livestock and a habitat for wild animals. However, the grazing livestock on a long-term scale has caused severe shrubization of the alpine shrubland. How to control the shrubization of grassland is very important. Therefore, the purpose was to explore the effects of long-term grazing and utilization patterns of different livestock on alpine shrubland. In this study, a collective pasture with basically the same grazing history, intensity and vegetation type was enclosed into two sample plots to graze by Cervus elaphus kansuensis (CEK), and mixed grazing by Bos grunniens (yak) and Ovis aries (Tibetan sheep) (YTS) from 1983 to 2019 respectively, and it provides an vital scientific basis for promoting the balanced development of grass and livestock and maintaining ecological balance. The results showed that, in 2018 and 2019, compared with grazing YTS, the biomass of the Salix cupularis in grazing CEK plot was 55.20% and 56.63% lower, the cluster height was 68.36% and 68.36% lower, the crown width was 75.34% and 76.00% lower, the coverage was 80.00% and 78.00% lower, and the difference was significant (P

The benthic dinoflagellate genus Gambierdiscus is the primary producer of toxins responsible for ciguatera poisoning (CP), a food intoxication endemic in tropical and subtropical areas of the world. We used high-performance liquid chromatography tandem high-resolution mass spectrometry (HPLC-HRMS) to investigate the toxin profile of Gambierdiscus balechii 1123M1M10, which was obtained from Marakei Island (2°01′N, 173°15′E), Republic of Kiribati, located in the central Pacific Ocean. Four new gambierone analogues including 12,13-dihydro-44-methylgambierone, 38-dehydroxy-12,13-dihydro-44-methylgambierone, 38-dehydroxy-44-methylgambierone, and desulfo-hydroxyl gambierone, and two known compounds, gambierone and 44-methylgambierone, were proposed by analyzing their fragmentation behaviors and pathways. Our findings provide new insights into the toxin profile of Gambierdiscus balechii 1123M1M10, which can be used as a biomarker for species identification, and lay the foundation for further toxin isolation and bioactivity studies of gambierones. [ABSTRACT FROM AUTHOR]