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Silver pomfret has been widely cultured in China due to its high economic value. Photobacterium damselae subsp. damselae (PDD) is a Gram-negative bacterium that has been shown to infect many fish species. To increase knowledge of the molecular mechanisms of the host defense against PDD, we conducted transcriptome analysis of head kidney in silver pomfret at 24 h and 72 h post-infection (hpi) via Illumina sequencing. The de novo assembly resulted in the identification of 79,063 unigenes, with 59,386 (75.11%) successfully annotated in public databases (NR, NT, KO, Swiss-Prot, Pfam, GO, and KOG databases). Comparison of gene expression profiles between PBS-injected fish (sham control) and PDD-challenged fish revealed 329 and 570 differentially expressed genes (DEGs) were screened at 24 hpi and 72 hpi, respectively. The DEGs were enriched in multiple immune-related pathways such as Hepatitis C, Gastric acid secretion, CAMs and Leukocyte transendothelial migration pathways, Primary immunodeficieny, ECM-receptor interaction, PI3K-Akt signaling pathway. The data obtained in the present study offers valuable information for acute immune response of silver pomfret challenged with PDD, which will facilitate further investigations on strategies against Photobacterium spp. infection in teleosts.

Controlling regioselectivity in activating C−H bonds in linear alkanes is challenging, as their multiple secondary C−H bonds have quite similar dissociation energies with no functional groups to differentiate between the bonds. Amidyl radicals generated from N‒halogen amides were reported to activate C−H bonds with an interesting 2-position selectivity. Here, with a possibility to access the amidyl radical photocatalytically, we coupled ligand-to-metal charge transfer (LMCT)-based radical generation and amide functional group on a tailor-designed metal-organic layer (MOL) material. We achieved efficient photo-chlorination of linear alkanes with 2-position selectivity. For example, with n-hexane as the substrate, 2-chloro-n-hexane was obtained with 85% selectivity and a turnover number of 2200 in 8 hours, together with a high apparent quantum yield of ~7% at room temperature. Transient absorption spectroscopy reveals that a FeIV species is involved in the initial photo-driven process that possibly oxidizes the amide center to an amidyl radical.

Subsalt imaging remains challenging despite a growing need for more accurate subsalt characterization. Long offsets, Wide-azimuth (WAZ) and full-azimuth (FAZ) acquisition technologies have provided step-change improvements in illumination, multiple attenuation, and signal-to-noise ratio (SNR). Recently, more advanced anisotropic velocity model-building techniques have been developed that greatly enhanced our ability to build accurate salt models and reduce velocity error. Reverse time migration (RTM) has become the preferred imaging algorithm due to its superior tolerance for complex salt geometry compared with traditional ray-based Kirchhoff migration. However, even with these developments, subsalt imaging still remains a significant challenge. Recently, vector image partitions (VIPs) from RTM have proven valuable for enhancing the image of challenging subsalt structures. In this paper, we present a new method for optimizing the final migrated image through enhancement of the consistent signal and suppression of noise among VIPs. We demonstrate the effectiveness of this method with a case study from the Gulf of Mexico. The result shows great improvements in the subsalt image quality in terms of SNR, reflector continuity, and wavelet consistency along reflectors.

Summary The Tulip 3D is a full azimuth single vessel Coil shooting survey in Indonesia. Coil geometry acquisition records a dataset with a wide range of source to detector azimuths. Amongst the numerous benefits of extended azimuth sampling methods is the advantage of illumination diversity. This has a desirable impact with tomographic velocity model building for depth imaging. The broad range of source to detector azimuth information allows an additional constraint on the travel time tomography by providing a network of intersecting rays not available with narrow azimuth geometries.

The Tulip 3D survey is a single-vessel full-azimuth Coil Shooting project in Indonesia. The circular geometry is very different to the conventional race-track towed streamer approach. While it results in many acquisition and imaging benefits, it also introduces a number of new challenges in the survey design, modeling, acquisition and processing workflows. This paper presents an overview of the data processing / imaging experience made during the coil shooting project. A processing workflow was tailored to address the challenges, and at the same time taking advantage of the opportunities provided by the circular geometry. The resulting images are demonstrably far superior to the vintage seismic data in the area, and provide a more suitable dataset for AVO inversion to seismic attributes and reservoir property characterization.

A new workflow is used to harness the synergy of borehole data and surface seismic in seismic data processing. It fully utilizes the borehole information in every step of seismic data processing. In this workflow, a model is first constructed from the borehole data and surface seismic data. At each step of data processing, processing parameters are optimized to ensure that the results are consistent with the model. The advantage of calibrating the seismic processing parameters via the use of borehole data is the significant reduction of many uncertainties for seismic interpretation and to increases the reliability of seismic data for quantitative interpretation. Two case studies in China clearly demonstrate he advantages of this new workflow.