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Geophysical fluid dynamics (GFD) is an interdisciplinary field that studies the large-scale motion of fluids in the natural world. With a wide range of applications such as weather forecasts and climate prediction, GFD employs various research approaches including in-situ observations, satellite measurements, numerical simulations, theoretical analysis, artificial intelligence, and physical model experiments in laboratory. Among these approaches, rotating tank experiments provide a valuable tool for simulating naturally-occurring fluid motions in laboratories. With proportional scaling and proper techniques, scientists can reproduce multi-scale physical processes of stratified fluids in the rotation system, which allows for the simulation of essential characteristics of fluid motions in the atmosphere and oceans. In this review, rotating tanks of various scales in the world are introduced, as these tanks have been actively used to explore fundamental scientific questions in ocean and atmosphere dynamics. To illustrate the GFD experiments, three representative cases are presented to demonstrate the frontier achievements in the the GFD study by using rotating tank experiments: mesoscale eddies in the ocean, convection processes, and plume dynamics. Detailed references for the experimental procedures are provided. Future studies are encouraged to further explore the utilization of rotating tanks with improvements in experimental design and integration of other research methods. This is a promising direction of GFD to help enhance our understanding of the complex nature of fluid motions in the natural world and to address the challenges posed by global environmental changes. [ABSTRACT FROM AUTHOR]

Cerebral revascularization is the ultimate treatment for a subset of complex middle cerebral artery (MCA) aneurysms. The decision for the revascularization strategy should be made during the treatment process. This study aimed to summarize the revascularization strategies for different types of complex MCA aneurysms and their outcomes. The clinical data of patients with complex MCA aneurysms who underwent cerebral revascularization since 2015 were analyzed retrospectively. The aneurysms were classified according to the location and other main characteristics that affect the selection of surgical modalities. The corresponding surgical modalities and treatment outcomes were summarized. A total of 29 patients with 29 complex MCA aneurysms were treated with cerebral revascularization from 2015 to 2022. Treated aneurysms were located at the prebifurcation segment in 7 patients, bifurcation segment in 12 patients, and postbifurcation segment in 10 patients. Surgical modalities in the prebifurcation segment included four high-flow extracranial-to-intracranial (EC-IC) bypasses with aneurysm trapping or proximal occlusion, two IC-IC bypasses with aneurysm excision, and one combination bypass with aneurysm excision. In the bifurcation segment, surgical modalities included two low-flow EC-IC bypasses with aneurysm excision or trapping, six IC-IC bypasses with aneurysm excision, three combination bypasses with aneurysm excision, and one constructive clipping with IC-IC bypass. In the postbifurcation segment, surgical modalities included nine IC-IC bypasses with aneurysm excision and low-flow EC-IC bypass with aneurysm trapping. The revascularization strategy for prebifurcation aneurysms was determined based on the involvement of lenticulostriate arteries, whereas the strategy for bifurcation aneurysms was determined based on the number of distal bifurcations and the shape of the aneurysm. The location of the aneurysm determined the revascularization strategy for aneurysms in the postbifurcation segments. Angiography demonstrated that aneurysms were completely obliterated in 26 cases and shrank in 3 cases, and all bypasses except one were patent. The mean follow-up period was 47.5 months. Three patients developed hemiplegic paralysis, and one developed transient aphasia postoperatively due to cerebral ischemia. No new neurological dysfunction occurred in the other 25 patients with no recurrence or enlargement of aneurysms during the follow-up. Prebifurcation aneurysms involving the lenticulostriate arteries require proximal occlusion with high-flow bypass. Most of the other aneurysms can be safely excised or trapped by appropriate revascularization strategies according to their location and orientation. [ABSTRACT FROM AUTHOR]

Automatic identification of rock thin sections provides valuable geological information for oil and gas exploration. However, the application of rock thin sections identification in new blocks works poorly. The reason is that the geological data of target blocks are extremely scarce in the early stage of exploration and development. Therefore, using an improved MaSE-ResNetXt network, data enhancement, feature extractors, online transfer learning and other strategies, a stable, efficient and continuously growing end-to-end identification system based on online transfer learning was built. In case one, the use of the basic MaSE-ResNetXt network on regional rock properties and model categories was compared with previous studies and experiments, and performance improvements of 5% and 14.3% were achieved respectively, which verified the high efficiency of the basic MaSE-ResNetXt network for feature extraction in a large-scale dataset. In case two, sensitivity analysis was conducted for similar categories that are easily confused, during which parameters of the network and optimizer were compared. The sensitivity problems of oolitic structure feature maps were discussed and optimized. After that, a weighted F1-score of 0.95 was reached, proving the prediction stability of cross-regional transfer. In case three, real-time online transfer learning for the cold boot was conducted with scarce geological data. Compared with the previous studies, the training speed was improved by 15 times, and the accuracy was improved by 20%. An improved method based on MaSE-ResNeXt with transfer learning using a neural network feature map for rock characteristics analysis was proposed. By proposing inheritance and real-time online transfer learning solutions, the problems of automatic rock thin sections identification in a new area were solved, and the geological data of multiple blocks were fully used. By doing so, this study bridged the gap that experiences from the former regions could not be inherited effectively for cross-regional rock thin sections identification, so that empowered the development of new blocks. [ABSTRACT FROM AUTHOR]

Mesoscale eddies play vital roles in ocean processes. Although previous studies focused on eddy surface features and individual three-dimensional (3D) eddy cases in the northwestern Pacific Ocean, the analysis of unique eddy 3D regional characteristics is still lacking. A 3D eddy detection scheme is applied to 9 years (2000–2008) of eddy-resolving Regional Ocean Modeling System (ROMS) output to obtain a 3D eddy dataset from the surface to a depth of 1 000 m in the northwestern Pacific Ocean (15°–35°N, 120°–145°E). The 3D characteristics of mesoscale eddies are analyzed in two regions, namely, Box1 (Subtropical Countercurrent, 15°–25°N, 120°–145°E) and Box2 (Southern Kuroshio Extension, 25°–35°N, 120°–145°E). In Box1, the current is characterized by strong vertical shear and weak horizontal shear. In Box2, the current is characterized by the strong Kuroshio, topographic effect, and the westward propagation of Rossby waves. The results indicate the importance of baroclinic instability in Box1, whereas in Box2, both the barotropic and baroclinic instability are important. Moreover, the mesoscale eddies' properties in Box1 and Box2 are distinct. The eddies in Box1 have larger number and radius but a shorter lifetime. By contrast, Box2 has fewer eddies, which have smaller radius but longer lifetime. Vertically, more eddies are detected at the subsurface than at the surface in both regions; the depth of 650 m is the turning point in Box1. Above this depth, the number of cyclonic eddies (CEs) is larger than that of anticyclonic eddies (AEs). In Box2, the number of CEs is dominant vertically. Eddy kinetic energy (EKE) and mean normalized relative vorticity in Box2 are significantly higher than those in Box1. With increasing depth, the attenuation trend of EKE and relative vorticity of Box1 become greater than those of Box2. Furthermore, the upper ocean (about 300 m in depth) contains 68.6% of the eddies (instantaneous eddy). Only 16.6% of the eddies extend to 1 000 m. In addition, about 87% of the eddies are bowl-shaped eddies in the two regions. Only about 3% are cone-shaped eddies. With increasing depth of the eddies, the proportion of bowl-shaped eddies gradually decreases. Conversely, the cone- and lens-shaped eddies are equal in number at 700–1 000 m, accounting for about 30% each. Studying the 3D characteristics of eddies in two different regions of the northwestern Pacific Ocean is an important stepping stone for discussing the different eddy generation mechanisms. [ABSTRACT FROM AUTHOR]

Sri Lanka seasonal warm pools (SSWPs) with high sea surface temperature (SST) (greater than 29.6 °C in summer and greater than 28 °C in winter) around the Sri Lanka Island are discovered using 37-year (1982–2018) satellite remote sensing SST data. It is identified that during the onset of the summer (winter) monsoon, the maximum SST in the SSWPs can be 1.8 °C (0.8 °C) higher than the surrounding ocean. Due to orographic influences, the wind intensity on the leeward side of Sri Lanka is weakened, reducing evaporation and oceanic mixing, and resulting in higher SST. The analysis of the long-term data shows that SSWPs are related to El Niño-Southern Oscillation (ENSO) events. Background currents are also found to play important roles in governing the SSWPs intensities through the heat advection. [ABSTRACT FROM AUTHOR]

As the west boundary fault of the Songliao Basin and the eastern margin of the Da Hinggan Mountains, the Nenjiang-Balihan fault is located in the central part of Northeast China. It is traditionally considered to be a huge deep-seated NNE-striking fault, characterized by a normal fault or detachment fault displacement. The field investigation resulted in the finding of ductile shear zones in the Lingxia and Louzidian areas, the middle and southern sectors of the fault system. The authors conducted measurements of structural elements in the field, micro-structural studies, finite strain measurements, a study on preferred crystal orientations of quartz determined by Electron Back Scatter Diffraction and muscovite Ar/Ar chronology of the deformed rocks in the ductile shear zone. The results show that the deformation features of the Lingxia and Louzidian ductile shear zones are similar, and that they represent one continuous fault, i.e., the middle-southern segment of the Nenjiang-Balihan Fault, which experienced a sinistral strike-slip ductile shearing in the Early Cretaceous (∼130 Ma). By measuring the displacement of the Xar Moron River suture and Wolegen Group on both sides of the Nenjiang-Balihan Fault, it is found that the cumulative strike-slip offset of the fault is about 40-50 km. [ABSTRACT FROM AUTHOR]

In the process of coalbed methane (CBM) mining, with the decreasing of reservoir pressure, stress sensitivity and matrix desorption shrinkage, which could be called self-regulating effect comprehensively, possess great effect on the gas adsorption due to the changing of pore volume. Therefore, it is necessary to modify the simplified local density (SLD) model to investigate the gas adsorption under reservoir conditions for an accurate prediction of CBM production. For the utilization of SLD adsorption model, assume the pores as slit pore. When pressure is lower than critical desorption pressure and keeps falling, the deformations of specific surface area (SSA) and pore width could be studied by the chosen Shi and Durucan (S&D) model. Furthermore, based on the variation relationship and the modification of SLD model, a new adsorption predicting model could be derived with the consideration of stress sensitivity, and matrix desorption shrinkage. In the absence of stress sensitivity and matrix desorption shrinkage, the calculated consequence is relatively smaller than the actual field adsorption data. What's more, the sensitivity analyses of Poisson's ratio, pore volume compressibility and critical desorption pressure are conducted with the application of this new model. At the same reservoir pressure, Poisson's ratio possesses negative relationship with modified adsorption, while pore volume compressibility and critical desorption pressure both possess positive influence on modified adsorption. The main reason is that Poisson's ratio affects matrix desorption shrinkage negatively, while pore volume compressibility and critical desorption pressure affect matrix desorption shrinkage positively. In spite of the opposite effect of stress sensitivity and matrix desorption shrinkage on pore deformation, matrix desorption shrinkage exhibits a dominant role in self-regulating. [ABSTRACT FROM AUTHOR]

The plant SABATH family of methyltransferases has important biological functions by methylating hormones and signaling molecules and other metabolites. In this study, we identified 47 RcSABATH genes from the Rosa chinensis genome, the majority of which are located in the cytoplasm. Following this, a comprehensive analysis was conducted on SABATH genes of Prunus persica, Malus domestica “Golden,” Prunus avium, and Prunus dulcis, which included phylogenetic and chromosome duplication analysis, gene structure examination, and functional domain and conserved motif analysis. The results revealed that SABATH family members across these five species were divided into three categories, with Group I containing the highest number of family members and Group III the lowest. Gene clusters were observed on the chromosomes of each species, indicating the occurrence of tandem repeat events during the evolutionary process of SABATH members. Furthermore, the analysis of gene structure, conserved motif, and conserved domain highlighted the diversity and conservation among SABATH family members. The transcriptome data of R12–26 and R13–54 infected by Marssonina rosae infection was used to screen 35 RcSABATHs, which were subsequently categorized into three groups (a, b, and c) based on their expression characteristics. Notably, Group c consisted of members that were induced and up-regulated during the late stage of R12–26 infection. Among the identified genes, RcSABATH20 drew our attention due to its involvement in various hormone and abiotic stress regulation pathways. To ascertain the function of RcSABATH20, we conducted experiments by treating the leaves of the resistant line R13–54 and susceptible line R12–26 with SA and the SA synthesis inhibitor AIP. The outcomes revealed a direct correlation between the expression of RcSABATH20 and resistance to rose black spots. Furthermore, it was observed that SA could enhance the expression of RcSABATH20, thereby contributing to the resistance against rose black spots. These findings establish a theoretical foundation for exploring the molecular mechanisms underlying SABATH resistance to rose black spots. [ABSTRACT FROM AUTHOR]