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The fructose-1,6-bisphosphate aldolase (FBA) gene family exists in higher plants, with the genes of this family playing significant roles in plant growth and development, as well as response to abiotic stresses. However, systematic reports on the FBA gene family and its functions in cucumber are lacking. In this study, we identified five cucumber FBA genes, named CsFBA1-5, that are distributed randomly across chromosomes. Phylogenetic analyses involving these cucumber FBAs, alongside eight Arabidopsis FBA proteins and eight tomato FBA proteins, were conducted to assess their homology. The CsFBAs were grouped into two clades. We also analyzed the physicochemical properties, motif composition, and gene structure of the cucumber FBAs. This analysis highlighted differences in the physicochemical properties and revealed highly conserved domains within the CsFBA family. Additionally, to explore the evolutionary relationships of the CsFBA family further, we constructed comparative syntenic maps with Arabidopsis and tomato, which showed high homology but only one segmental duplication event within the cucumber genome. Expression profiles indicated that the CsFBA gene family is responsive to various abiotic stresses, including low temperature, heat, and salt. Taken together, the results of this study provide a theoretical foundation for understanding the evolution of and future research into the functional characterization of cucumber FBA genes during plant growth and development. [ABSTRACT FROM AUTHOR]

Removal of water‐layer‐related multiples in shallow water remains a challenge due to a lack of near‐offset data. We have developed a shallow water multiple attenuation approach by constructing the impulse response of the water bottom for the removal of water‐layer‐related multiples. The impulse response of the seafloor is formed by the convolution of its traveltime response and amplitude response. It uses the superposition of the original shallow water demultiple operator to obtain traveltime information and uses the deconvolution method to estimate its dynamic components from the original shallow water demultiple operator to build new operators. The impulse response can be correctly constructed not only for near offsets but for moderate and far offsets as well. A three‐term subtraction strategy by predicting source‐side, receiver‐side and both source‐side and receiver‐side multiples is adopted in our approach for attenuating shallow multiples without over‐prediction. Numerical examples with two synthetic datasets and 2D and 3D field datasets demonstrate that our approach gives a desirable performance. [ABSTRACT FROM AUTHOR]

The increasing need for petrophysical parameter inversion has spurred the advancement of full-waveform inversion (FWI). This study introduces a new inversion method that can directly estimate petrophysical parameters from seismic waveform data. Specifically, we modified the regular elastic wave equation by including Biot poroelastic parameters and designed an inversion workflow based on the framework of elastic FWI. The newly introduced inversion algorithms have demonstrated their effectiveness and accuracy using the Marmousi model and a synthetic model related to the gas hydrate deposits based on the Shenhu area of the South China Sea. Our work demonstrates the feasibility of directly inverting petrophysical parameters and assessing if a deposit contains gas hydrate. [ABSTRACT FROM AUTHOR]

Nowadays, the most successful applications of full‐waveform inversion (FWI) involve marine seismic data under acoustic approximations. Elastic FWI of land seismic data is still challenging in theory and practice. Here, we propose a full dispersion spectrum inversion method and apply it to seismic data acquired in West Antarctica. Inspired by the conventional surface wave dispersion curve inversion method, we propose to invert the surface wave dispersion spectrum instead of the complicated waveforms. We compare the frequency‐velocity, frequency‐slowness, and frequency‐wavenumber spectra in terms of their ability to resolve dispersion modes and the feasibility of their adjoint updates and conclude that the frequency‐slowness spectrum is the best for our inversion objectives. We test four objective functions, subtraction, zero‐lag crosscorrelation, optimal transport, and the local‐crosscorrelation to quantify the spectrum mismatch and provide the corresponding adjoint source. We then theoretically analyze the convexity of the proposed objective functions and examine their convergence behavior using numerical examples. We also compare the proposed method with the classic FWI method and the traditional surface wave dispersion curve inversion method and discuss the strengths and weaknesses of each method. This technique is employed to evaluate the shallow velocity structures beneath a seismic array stationed in West Antarctica. Our proposed inversion scheme is also useful for more general applications such as imaging the shallow subsurface of the critical zones, like geothermal reservoirs, and CO2 storage sites. Plain Language Summary: Seismic full‐waveform inversion (FWI) is a cutting‐edge inversion method used for uncovering the Earth's subsurface structure. With the growing interest in clean energy and CO2 sequestration, exploring the subsurface in land is becoming crucial. However, there are only a few success stories of seismic FWI applied to land data mainly because of the complexity of the near‐surface and the increased nonlinearity of the problem. Here, we propose a full dispersion spectrum inversion method that seeks optimal velocity models in the subsurface by matching the seismic dispersion spectra. Dispersion spectra are the skeleton of seismic surface waves, which are simpler to quantify yet retain the key dispersion information of surface waves. It is generally easier for humans, as well as algorithms, to match simplified representations of the observed and simulated data, such as the dispersion spectrum, instead of the seismic waveforms themselves. The proposed method expands conventional 1D dispersion curve inversion to multiple dimensions and is accomplished under the framework of FWI. The proposed inversion method applies to seismic imaging applications in exploration and global seismology. Key Points: We propose a full dispersion spectrum inversion method for imaging the near‐surface and apply it to seismic array data collected in West AntarcticaThe surface wave frequency‐slowness spectrum is preferred over the frequency‐velocity and the frequency‐wavenumber spectra to measure the misfit in the proposed inversionThe optimal transport objective function is immune to cycle skipping but has a lower model resolution [ABSTRACT FROM AUTHOR]

In consideration of the increased activity of Pt-based catalysts for methanol oxidation in direct methanol fuel cells, it is necessary to apply an ideal support in the construction of Pt-based catalyst for methanol oxidation. In this study, Ag/g-C3N4 nanosheets (Ag/GCNN) nanocomposites with different Ag contents were synthesized and used as the progressive support to construct Pt/Ag/GCNN catalyst. As a nitrogen-rich polymeric semiconductor, GCNN is easily coordinated with various metals. The introduction of Ag nanoparticles can improve the electrical conductivity of the catalyst and cooperate with Pt for optimizing the performance of electrocatalytic oxidation of methanol. The electrochemical experiment results demonstrated that Pt/Ag/GCNN has higher electrocatalytic activity and stability for methanol oxidation than Pt/GC and Pt/GCNN. The mass activity of Pt/Ag/GCNN-0.6 (18.66 mA mgPt−1) is 7.07, 4.60 and 1.26 times that of Pt/GCNN (4.06 mA mgPt−1), Pt/Ag/GCNN-0.4 (4.06 mA mgPt−1) and Pt/Ag/GCNN-0.8 (14.76 mA mgPt−1) at the forward peak potential. The Jf/Jb ratio of Pt/Ag/GCNN-0.6 is 3.31, which is bigger than that of Pt/GCCN (2.62), Pt/Ag/GCNN-0.4 (2.69), and Pt/Ag/GCNN-0.8 (2.56). A suitable mechanism was proposed to explain that Ag/GCNN supported Pt catalyst can improve the CO toxicity resistance and electrocatalytic performance. Based on the coordination of GCNN, Ag was first modified to form a support, and then the remaining coordination sites were used to support Pt. It provided a new strategy for the design of catalysts for methanol electrooxidation. [ABSTRACT FROM AUTHOR]

Regional seismic reflection profiles and deep exploratory wells have been used to characterize the subsurface structural trends and seismo-stratigraphic architecture of the sedimentary successions in offshore Indus Pakistan. To improve the data quality, we have reprocessed the seismic data by applying signal processing scheme to enhance the reflection continuity for obtaining better results. Synthetic seismograms have been used to identify and tie the seismic reflections to the well data. The seismic data revealed tectonically controlled, distinct episodes of normal faulting representing rifting during Mesozoic and transpression at Late Eocene time. A SW-NE oriented anticlinal type push up structure is observed resulted from the basement reactivation and recent transpression along Indian Plate margin. The structural growth of this particular pushup geometry was computed. Six mappable seismic sequences have been identified on seismic records. In general, geological formations are at shallow depths towards northwest due to basement blocks uplift. A paleoshelf is also identified on seismic records overlain by Cretaceous sediments, which is indicative of Indian-African Plates rifting at Jurassic time. The seismic interpretation reveals that the structural styles and stratigraphy of the region were significantly affected by the northward drift of the Indian Plate, post-rifting, and sedimentation along its western margin during Middle Cenozoic. A considerable structural growth along the push up geometry indicates present day transpression in the margin sediments. The present comprehensive interpretation can help in understanding the complex structures in passive continental margins worldwide that display similar characteristics but are considered to be dominated by rifting and drifting tectonics.