Rice (Oryza sativa L.) is one of the most important food crops in the world. In plants, jasmonic acid (JA) plays essential roles in response to biotic and abiotic stresses. As one of the largest transcription factors (TFs), basic region/leucine zipper motif (bZIP) TFs play pivotal roles through the whole life of plant growth. However, the relationship between JA and bZIP TFs were rarely reported, especially in rice. In this study, we found two rice homologues of Arabidopsis VIP1 (VirE2-interacting protein 1), OsbZIP81, and OsbZIP84. OsbZIP81 has at least two alternative transcripts, OsbZIP81.1 and OsbZIP81.2. OsbZIP81.1 and OsbZIP84 are typical bZIP TFs, while OsbZIP81.2 is not. OsbZIP81.1 can directly bind OsPIOX and activate its expression. In OsbZIP81.1 overexpression transgenic rice plant, JA (Jasmonic Acid) and SA (Salicylic acid) were up-regulated, while ABA (Abscisic acid) was down-regulated. Moreover, Agrobacterium, Methyl Jasmonic Acid (MeJA), and PEG6000 can largely induce OsbZIP81. Based on ChIP-Seq and Random DNA Binding Selection Assay (RDSA), we identified a novel cis-element OVRE (Oryza VIP1 response element). Combining ChIP-Seq and RNA-Seq, we obtained 1332 targeted genes that were categorized in biotic and abiotic responses, including α-linolenic acid metabolism and fatty acid degradation. Together, these results suggest that OsbZIP81 may positively regulate JA levels by directly targeting the genes in JA signaling and metabolism pathway in rice.

Cement bond evaluation is of great significance in oil/gas development, geothermal production and CO2 storage. Advanced ultrasonic pitch-catch measurement exhibits poor performances in determining the cement-formation interface due to weak reflections from cement-formation interface (TIE) in non-axisymmetric complex ultrasonic environments. To deal with this issue, we utilize a reverse time migration (RTM) approach for ultrasonic pitch-catch measurements to image the cased-hole structure especially for the cement-formation interface. To further enhance cased-hole RTM feasibility, a phase-shift interpolation technique is applied to reconstruct ultrasonic array waveforms from limited receivers in the pitch-catch measurement. Synthetic examples demonstrate that RTM is capable of imaging the cement-formation interface with a high resolution under various eccenterings of casing and tool. This study illustrates that small errors introduced by phase-shift interpolations do not greatly degrade the imaging result of RTM. Furthermore, tests for inclined cement-formation interface demonstrate that the RTM is able to recover the true position and geometry of the cement-formation interface when a smoothed velocity model is offered. In addition, although RTM is sensitive to the velocity perturbation, it is possible to image the cased hole structure by employing a multi-step strategy assuming that the position and thickness of steel casing is unknown.

As a key technology to evaluate cement bond in cased hole, advanced ultrasonic logging tool combines pulse-echo and pitch-catch measurements where the latter one provides reflections from cement-formation interface [named as third-interface-echo (TIE)] to evaluate the bond condition and determine casing eccentering as well as cement velocity. However, the TIE would be weak and not easy to pick due to the eccentered tool and casing and it would overlap with the strong multiple reflections between the casing inner surface and the transducer-housing tool. In this study, we propose a deep-learning workflow to extract weak TIE from noisy data and to preserve its amplitude at the same time. Firstly, we use synthetic waveforms from thousands of finite difference simulations as initial training dataset to train a deep-learning network which is modified from a network in speech separation. Then the trained model is used to predict the field data through an active learning strategy. The improved network is further used to extract the weak TIEs which are not easy to pick in the initial deep-learning model. Finally, the TIE waves image is converted to a pseudo-velocity image to obtain the minimum travel-time path by solving Eikonal equation. The shortest travel-time path is used as the TIE arrival-time. In addition, a 3D visualization is used to display the borehole shape from the picked arrival-time. The applications in synthetic data, and dataset from a calibration well illustrate a good performance of the proposed workflow where the weakest TIE extracted from the network can reach to 50 dB comparing to the maximum amplitude in the full waveform. The picked arrival times can be used to reconstruct a borehole shape.

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