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As one of the main imaging methods, a lot of attention has been directed to reverse time migration anisotropic media. However, reverse time migration still faces cost and memory limitations, especially in imaging high frequencies. A coordinate transformation strategy in transversely isotropic media with a vertical axis of symmetry (VTI) was utilized to obtain high-resolution images useful for stratigraphic interpretation. The coordinate transformation converted traditional depth domain imaging into pseudo-depth domain imaging. In addition, this paper used the Graphics Processing Unit (GPU) parallel strategy and compared the imaging approach with the conventional acoustic isotropy method. By testing several models and field data, it concludes that Graphics Processing Unit parallel strategy can significantly improve the computational efficiency of imaging. The pseudo-depth domain method also has obvious advantages in computational time and memory consumption. Moreover, it is more reasonable when considering anisotropy for complex laminated layers.

BackgroundChina's research on acute intermittent porphyria (AIP) is relatively limited. Due to most medical workers' insufficient understanding, AIP is easily misdiagnosed, and mistreated, leading to delayed appropriate treatment.ObjectiveTo analyze the clinical data of Chinese individuals with AIP with hydroxymethylbilane synthase (HMBS) gene mutation who were reported in published studies, improving medical workers' understanding of AIP.MethodsDatabases of PubMed, CNKI, Wanfang Data and CQVIP were searched for published articles about Chinese AIP cases from inception to June 30, 2021. Literature screening based on the inclusion and exclusion criteria of this study and data extraction were performed by two researchers, separately. Information regarding general data, clinical manifestations, results of laboratory tests, treatments, and gene mutations of AIP patients was analyzed.ResultsA total of 32 articles were included, containing 65 AIP patients (56 females and 9 males) with the age mostly between 20-39 years old 〔83.1% (54/65) 〕. Most of AIP patients' admission were for abdominal pain〔63 cases (96.9%) 〕, often accompanied by nausea, vomiting, and constipation. 56.9% (37/65) of AIP patients suffered from central neuropathy, disturbance of consciousness (25 cases) , epileptiform seizures (22 cases) and respiratory muscle paralysis (6 cases) . 13.8% (9/65) of patients experienced peripheral neuropathy including fatigue (6 cases) and limb numbness (4 cases) . 30.8% (20/65) of patients had autonomic neuropathy such as hypertension and tachycardia. 9.2% (6/65) of patients experienced spirit symptoms, such as depression, anxiety and hallucination. Thirty-five patients had generated multiple acute attacks of AIP. In some patients, the onset of AIP may have been related to menstruation (9 cases) , pregnancy and childbirth (4 cases) , fatigue (3 cases) , alcohol consumption (2 cases) , and dieting (1 case) . 25 patients developed hyponatremia. There were 11 cases of anemia and 11 cases of abnormal liver function. Six patients were in abnormal renal function. 1 case was caught in disorder of cortisol rhythm. Twenty-seven patients received carbohydrate loading therapy, and 25 of them were improved. Two patients were treated with carbohydrate loading combined with heme therapy, and 1 eventually improved. A total of 26 HMBS gene mutations were included in the study, where in the p.R173W, p.R173Q, p.T269R, p.W283X and p.A330P mutations were detected in multiple patients. And different patients with the same gene mutation may also show different clinical phenotypes.ConclusionAIP is a disease with complex and variable clinical manifestations and heterogeneous severity of disease. The acute attack of AIP should be considered if patients, especially young female patients, are clinically found to be with unexplained abdominal pain, epileptiform seizures, disturbance of consciousness, hypertension, tachycardia and hyponatremiain. Currently, carbohydrate loading therapy is mainly applied to control the attack of AIP in China. In terms of factors affecting the clinical phenotype of AIP, further exploration still needs to be carried out.

The Conditional Colour-Magnitude Distribution (CCMD) is a comprehensive formalism of the colour–magnitude–halo mass relation of galaxies. With joint modelling of a large sample of SDSS galaxies in fine bins of galaxy colour and luminosity, Xu et al. inferred parameters of a CCMD model that well reproduces colour- and luminosity-dependent abundance and clustering of present-day galaxies. In this work, we provide a test and investigation of the CCMD model by studying the colour and luminosity distribution of galaxies in galaxy groups. An apples-to-apples comparison of group galaxies is achieved by applying the same galaxy group finder to identify groups from the CCMD galaxy mocks and from the SDSS data, avoiding any systematic effect of group finding and mass assignment on the comparison. We find an overall nice agreement in the conditional luminosity function (CLF), the conditional colour function (CCF), and the CCMD of galaxies in galaxy groups inferred from CCMD mock and SDSS data. We also discuss the subtle differences revealed by the comparison. In addition, using two external catalogues constructed to only include central galaxies with halo mass measured through weak lensing, we find that their colour-magnitude distribution shows two distinct and orthogonal components, in line with the prediction of the CCMD model. Our results suggest that the CCMD model provides a good description of halo mass-dependent galaxy colour and luminosity distribution. The halo and CCMD mock catalogues are made publicly available to facilitate other investigations. [ABSTRACT FROM AUTHOR]

As one of the main seismic imaging methods, conventional reverse time migration (RTM) may not produce high-quality images in areas with non-flat surfaces and anisotropy because the complex surfaces have a great impact on seismic wave simulation, resulting in strong scattering waves. In addition, in isotropic acoustic (ISO) RTM, the neglection of the anisotropic effects will lead to incorrect travel times during source and receiver wavefield extrapolation. To overcome these problems, we develop a topographic pseudo-acoustic vertical transverse isotropic (VTI) RTM algorithm based on the body-fitted grid. In this method, we first derive anisotropic pseudo-acoustic wave equations in the curvilinear coordinate system. Then, the Lebedev grid finite-difference scheme is used to update these equations to simulate wavefields. Finally, we use the source-normalized cross-correlation imaging condition to realize RTM. Numerical tests are performed to evaluate the feasibility and applicability of the proposed method. The imaging results show that the proposed method can remove the effect of surface topography and anisotropy on seismic wave propagation and improve migration imaging precision. [ABSTRACT FROM AUTHOR]

Large-scale spinning of high-performance SiO2 porous nanofibers remains a pivotal challenge in facilitating their utilization for flexible thermal insulation purposes. Herein, massive spinning of SiO2 porous nanofibers was achieved through the solution blow spinning (SBS) process utilizing microemulsion polysiloxane solutions. Using MK siloxane polymer as the Si source, a solution characterized by high purity and excellent uniformity was obtained. Multicomponent spinnable microemulsion precursor was prepared by incorporating paraffin as the sacrificial phase, Span 80 and Tween 80 as surfactants, and polyvinylpyrrolidone as the spinning aid. Through optimization of the spinnable solution composition and SBS process parameters, high-speed spinning of paraffin/MK precursor nanofibers was accomplished with a rate of 20 mL·h–1. Subsequent high-temperature pyrolysis facilitated the conversion of organic paraffin/MK nanofibers into SiO2 nanofibers with controllable pores structure. Porous SiO2 nanofiber sponges fabricated using the microemulsion SBS technique exhibit distinctive lightweight and thermal insulation properties [0.037 W·(m·K)−1]. These properties promise to facilitate massive spinning of high-performance inorganic fiber sponges for applications in high-temperature thermal management. [ABSTRACT FROM AUTHOR]

Highly efficient production of porous carbon nanofibers (PCNFs) is indispensable for applications in adsorption, thermal insulation, catalysis, batteries, etc. Herein, rapid fabrication of PCNFs with flexible and efficient adsorption properties was achieved through polymer blend blow spinning at a rate of 10–30 mL·h–1. Polyacrylonitrile (PAN) was used as the organic precursor to prepare PCNFs, with varying mass fractions of poly-(methyl methacrylate) (PMMA) microspheres employed as pore-forming agents. Following high-temperature carbonization, the diameter of PCNFs was adjusted within a range of 0.2–1.2 μm, resulting in a high specific surface area of 34.63 m2 g–1 and a pore distribution of 3–20 nm. PCNFs demonstrated exceptional mechanical resilience, withstanding cyclic compression strains of up to 60% and achieving a peak compression stress of 12.2 kPa. Additionally, PCNFs exhibited a significant adsorption capacity for oils and benzene, coupled with superior thermal insulation performance and an ultralow thermal conductivity of 0.022 W·(m·K)−1. PCNFs can also be used as sensors and demonstrated unmatched sensitivity to minute pressure variations ranging from 0 to 1 N. The polymer blend blow spinning technique showcased operational simplicity and remarkable versatility across various materials. This excellent functional expandability demonstrated that the strategy held significant potential for the large-scale production of multifunctional PCNFs. [ABSTRACT FROM AUTHOR]

The temporal electrical performance of a 63NiO/ZnO integrated betavoltaic battery is examined. Utilizing first-principles calculations combined with Monte Carlo simulations, we study the energy band structure and density of states of 63NiO, particularly when 63Ni undergoes a 12.5% decay. Our findings reveal that, when the 63NiO layer is 4 μm thick, the decay's impact is akin to substitution doping. Leveraging this insight, we employed Silvaco ATLAS software to simulate the time-dependent short-circuit current, open-circuit voltage, maximum output power, and energy conversion efficiency of the 63NiO/ZnO integrated betavoltaic battery. These results were compared with those of a NiO/ZnO separate betavoltaic battery. At 6.93 years, the maximum output power of the integrated and separate devices was found to be 10.19 and 9.77 nW/cm2, respectively, corresponding to 8.67% and 88.79% of their initial values. Notably, prior to this point, the integrated device exhibited significantly superior performance; at 4.58 years, it demonstrated 2.28 times higher maximum output power compared to the separate device, followed by only a slight difference in performance thereafter. [ABSTRACT FROM AUTHOR]

Osmotic stress is a major threaten to the growth and yield stability of Brassica napus. Post-translational modification with O-linked β-N-acetylglucosamine (O-GlcNAc) is ubiquitous in plants, and participates in a variety of signal transduction and metabolic regulation. However, studies on the role of O-GlcNAc transferase (OGT) in osmotic stress tolerance of plants are limited. In previous study, a O-glycosyltransferase, named BnaC09.OGT, was identified from the B. napus variety 'Zhongshuang 11' by yeast one hybrid with promoter of BnaA01.GPAT9. It was found that BnaC09.OGT localized in both nucleus and cytoplasm. The spatiotemporal expression pattern of BnaC09.OGT exhibited tissue specificity in developmental seed, especially in 15 days after pollination. In view of osmotic stress inducing, the BnaC09.OGT overexpression and knockout transgenic lines were constructed for biological function study. Phenotypic analysis of BnaC09.OGT overexpression seedlings demonstrated that BnaC09.OGT could enhance osmotic stress tolerance than WT and knockout lines in euphylla stage under 15% PEG6000 treatment after 7 days. In addition, compared with WT and knockout lines, overexpression of BnaC09.OGT had significantly higher activities of antioxidant enzymes (SOD and POD), higher content of soluble saccharide, and while significantly less content of malondialdehyde, proline and anthocyanidin under 15% PEG6000 treatment after 7 days. On the other hand, the unsaturated fatty acid content of BnaC09.OGT overexpression was significantly higher than that of WT and knockout lines, so it is speculated that the BnaC09.OGT could increase unsaturated fatty acid biosynthesis for osmotic stress tolerance by promoting the expression of BnaA01.GPAT9 in glycerolipid biosynthesis. In summary, the above results revealed that the function of BnaC09.OGT provides new insight for the analysis of the pathway of O-glycosylation in regulating osmotic stress tolerance in B. napus. [ABSTRACT FROM AUTHOR]