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Due to excellent performance properties such as strong activity and high selectivity, single-atom catalysts have been widely used in various catalytic reactions. Exploring the application of single-atom catalysts and elucidating their reaction mechanism has become a hot area of research. This article first introduces the structure and characteristics of single-atom catalysts, and then reviews recent preparation methods, characterization techniques, and applications of single-atom catalysts, including their application potential in electrochemistry and photocatalytic reactions. Finally, application prospects and future development directions of single-atom catalysts are outlined.

The Meso-Cenozoic tectonic activities of the Central Asian Orogenic Belt (CAOB) played an important role in controlling the present-day topography of Central Asia. The Altai orogenic belt is a key component in the southern CAOB; so far, there is still a lack of sufficient constraints on the time and mechanism of its tectonic reactivation since the Mesozoic. In this contribution, we present new zircon and apatite (U-Th)/He and apatite fission track thermochronological data from granitoid samples in the Habahe area, western Altai orogenic belt. Therein zircon (U-Th)/He ages range from ∼230 to ∼238 Ma, apatite fission track central ages are ∼140-157 Ma, and apatite (U-Th)/He ages vary from ∼134 to ∼149 Ma. Based on the associated thermal history modeling results, the Habahe area underwent a moderate cooling during the Late Triassic to Middle Jurassic (∼230-170 Ma) with a cooling rate of ∼0.8-1.1°C/Ma and a subsequent moderate to slightly rapid cooling stage during the Middle Jurassic to Early Cretaceous (170-130 Ma) with a cooling rate of 1.5-2.3°C/Ma. We propose that this prolonged cooling stage occurred under a long-lasting contractional tectonism in the western Altai throughout the early Mesozoic, which was produced by multiplate convergence in East Asia during this period, mainly including the consumption of the Mongol-Okhotsk Ocean in the northeast and the Meso-Tethys Ocean in the south. The region experienced rather limited Late Cretaceous-Cenozoic cooling and exhumation due to insufficient reactivation and weak surficial erosion.

As a continuation of [Li, J. and Wang, Y. N., Structural stability of steady subsonic Euler flows in 2D finitely long nozzles with variable end pressure, J. Differential Equations , 413 , 2014, 70–109], in this paper, the authors study the structural stability of three dimensional axisymmetric steady subsonic Euler flows in finitely long curved nozzles. The reference flow is a general subsonic shear flow in a three dimensional regular cylindrical nozzle with general size of vorticity and without stagnation points. The problem is described by the well-known steady compressible Euler system. With a class of admissible physical conditions and prescribed pressure at the entrance and the exit of the nozzle respectively, they establish the structural stability of this kind of axisymmetric subsonic shear flow with no-zero swirl velocity. Due to the hyperbolic-elliptic coupled form of the Euler system in subsonic regions, the problem is reformulated via a twofold normalized process, including straightening the lateral boundary of the nozzle under the natural Cartesian coordinates and reformulating the problem under the cylindrical coordinates. Accordingly, the Euler system is decoupled into an elliptic mode and three hyperbolic modes with some artificial singular terms under the cylindrical coordinates. The elliptic mode is a mixed type boundary value problem of first order elliptic system for the pressure and the radial velocity angle. Meanwhile, the hyperbolic modes are transport type to control the total energy, the specific entropy and the swirl velocity, respectively. The estimates as well as well-posedness are executed in a Banach space with optimal regularity under the natural Cartesian coordinates in place of the cylindrical coordinates. The authors develop a systematic framework to deal with the artificial singularity and the non-zero swirl velocity in three dimensional axisymmetric case. Their strategy is helpful for other three dimensional problems under axisymmetry.

The North Huicheng Basin strike-slip fault system is on the northeastern frontier of the Tibetan Plateau and separates the West and East Qinling differential orogeny. However, the deformation mechanism of this strike-slip fault system and its exact tectonic significance are unclear. Here, we carried out systematic field structural analysis, physical analog modeling, and multiproxy geochronological dating to address these issues. The field structural analysis indicates that the North Huicheng Basin strike-slip fault system was induced from the plate-like movement of the West and East Qinling Orogens, which underwent multiple left-lateral strike-slip faulting and controlled salient and recessed structures. The scaled physical analog experiment results confirm this hypothesis and reveal the primary spatial-temporal deformational kinematic process. Combined with published works, multiproxy geochronological dating (zircon U-Pb age of 213 Ma, biotite 40Ar/39Ar age of 203 Ma, and apatite fission-track age of 56 Ma) outlines the main thermal history of the hanging wall. Based on the above facts, the integrated research suggests that multistage strike-slip faulting played a significant role in the main tectonic events, that is, Late Triassic magmatic emplacement, Jurassic/Cretaceous local pull-apart, and Cenozoic rapid exhumation driven by Tibetan Plateau growth.

Understanding the molecular mechanisms that regulate grain yield is important for improving agricultural productivity. Protein ubiquitination controls various aspects of plant growth but lacks understanding on how E2-E3 enzyme pairs impact grain yield in major crops. Here, we identified a RING-type E3 ligase SGD1 and its E2 partner SiUBC32 responsible for grain yield control in Setaria italica . The conserved role of SGD1 was observed in wheat, maize, and rice. Furthermore, SGD1 ubiquitinates the brassinosteroid receptor BRI1, stabilizing it and promoting plant growth. Overexpression of an elite SGD1 haplotype improved grain yield by about 12.8% per plant, and promote complex biological processes such as protein processing in endoplasmic reticulum, stress responses, photosystem stabilization, and nitrogen metabolism. Our research not only identifies the SiUBC32-SGD1-BRI1 genetic module that contributes to grain yield improvement but also provides a strategy for exploring key genes controlling important traits in Poaceae crops using the Setaria model system. Researchers identify an E3 ligase SGD1 and its E2 partner responsible for grain yield control using foxtail millet, and reveal its conserved role in wheat, maize, and rice. Furthermore, SGD1 ubiquitinates the brassinosteroid receptor BRI1 thus stabilizing it and promoting grain yield in crops.

The Belt and Road Initiative (BRI), as a green development initiative, highlights the importance of regional cooperation among participating countries to address the possibility of non-native organisms. We created a database of 8655 non-native insect records from 3059 non-native insect species of 312 families to better understand invasion vulnerability. Results showed that Coleoptera, Hemiptera, and Hymenoptera dominated, comprising 72.54% of all recorded non-native insects. Hotspots of non-native insects were primarily developed BRI corridor nations, such as New Zealand, Czechia, Austria and South Africa. These insects largely originated from Asia, Europe, and North America, with Oceania contributing the fewest. Model averaging and PLS path modeling showed that the merchandise imports and international tourism were positively correlated with non-native insect occurrences. 49.63% of the countries, including China, South Korea, Russia and Poland, were identified as medium- to high-vulnerable regions for non-native insect introduction. Finally, we recommend intergovernmental collaboration to promote proactive prevention and control measures for regional biosecurity.

The NuA3 histone acetyltransferase complex in budding yeast, composed of six subunits, specifically acetylates lysine 14 on histone H3 (H3K14), thereby regulating various biological processes. Despite its importance, the structural basis and mechanism underlying histone tail recognition and substrate specificity of the NuA3 complex have remained elusive. Here we report cryo-electron microscopy structures of the NuA3 complex in its apo form, bound to acetyl-coenzyme A (acetyl-CoA), and in a complex with both the histone H3 tail and acetyl-CoA. Our structure shows that the histone tail-binding cleft of NuA3 is formed cooperatively by two subunits, the catalytic subunit Sas3 and the non-catalytic subunit Nto1. A hydrophobic part of the cleft engages the region preceding H3K14 (residues 9-12), while a network of polar interactions between the cleft and the backbone of H3 residues 12-15, particularly involving Gly13, contributes to substrate specificity. The yeast NuA3 histone acetyltransferase complex catalyzes acetylation of histone H3 at lysine 14 (H3K14). Here, the authors present the cryo-EM structures of NuA3 in the apo state and bound to acetylcoenzyme A and the histone tail, illustrating the molecular basis of histone recognition and the mechanism of H3K14 acetylation.

Background Head and neck cancers are aggressive cancers, most clinical studies focused on the prognosis of patients with head and neck cancer. However, perioperative mortality was rarely mentioned. Methods A retrospective analysis was performed using all head and neck cancer patients admitting in the Department of Oral and Maxillofacial Surgery of the Second Xiangya Hospital, Central South University from January 2010 to December 2019. The analysis of overall survival and progression-free survival were performed using the Kaplan–Meier method, and cross tabulation with chi-squared testing was applied to analyze the difference in parameters between groups. Results From January 2010 to December 2019, a total of 6576 patients with head and neck cancers were admitted to our department and 7 died in the hospital, all of whom were middle-aged and elderly patients including 6 males and 1 female. The perioperative mortality rate (POMR) was about 1‰. The causes of death included acute heart failure, rupture of large blood vessels in the neck, hypoxic ischemic encephalopathy due to asphyxia, respiratory failure and cardiopulmonary arrest. Conclusion Preoperative radiotherapy, previous chemotherapy, hypertension, diabetes, advanced clinical stage and postoperative infection are risk factors for perioperative mortality of head and neck cancer.

Background Oral squamous cell carcinoma (OSCC) is an invasive cancer with a high recurrence rate. Most clinical studies have focused on the prognosis of patients with OSCC, few have investigated the causes and interventions that affect the recurrence. Our study is to explore the temporal and spatial patterns of recurrence in OSCC. Methods 234 OSCC patients with recurrence in our hospital and 64 OSCC patients with recurrence in TCGA database were included in the study. Log-rank test and Multivariate Cox Regression Analysis were used to determine whether there was a significant difference between each selected demographic or clinical factors and recurrence. The Kaplan–Meier method was used to plot survival curves for each recurrence interval. Results The proportion of OSCC patients in clinical and TCGA with early recurrence was 93.6% and 84.4%, respectively. Age, chewing betel nut, previous radiotherapy, histopathological grading of the primary tumor (poorly differentiated), lymph node metastasis and postoperative infection were found to be associated with the timing of recurrence. It was found that tongue cancer has more regional recurrences, while buccal cancer is mostly local and loco-regional recurrences. The earlier the recurrence, the greater the possibility of local-regional recurrence and the worse the prognosis. Conclusion Most of recurrent OSCC patients present early recurrence (< 18 months) with poor prognosis, and early recurrence is more prone to local recurrence. Moreover, recurrence site is related with primary site of OSCC.

Photocatalytic solar‐to‐fuel conversion over metal halide perovskites (MHPs) has recently attracted much attention, while the roles of defects in MHPs are still under debate. Specifically, the mainstream viewpoint is that the defects are detrimental to photocatalytic performance, while some recent studies show that certain types of defects contribute to photoactivity enhancement. However, a systematic summary of why it is contradictory and how the defects in MHPs affect photocatalytic performance is still lacking. In this review, the innovative roles of defects in MHP photocatalysts are highlighted. First, the origins of defects in MHPs are elaborated, followed by clarifying certain benefits of defects in photocatalysts including optical absorption, charge dynamics, and surface reaction. Afterward, the recent progress on defect‐related MHP photocatalysis, i.e., CO2 reduction, H2 generation, pollutant degradation, and organic synthesis is systematically discussed and critically appraised, putting emphasis on their beneficial effects. With defects offering peculiar sets of merits and demerits, the personal opinion on the ongoing challenges is concluded and outlining potentially promising opportunities for engineering defects on MHP photocatalysts. This critical review is anticipated to offer a better understanding of the MHP defects and spur some inspiration for designing efficient MHP photocatalysts. The recent progress on defect engineering of metal halide perovskites (MHPs) for photocatalysis is summarized and reexamined, focusing on discussing and critically appraising the benefits of defects, together with outlining potentially promising opportunities and directions for moving MHP‐based photocatalysis research forward.