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Hot dry rock (HDR) geothermal energy has many advantages, such as being renewable, clean, widely distributed, and without time and weather limitations. Hydraulic fracturing is usually needed for the exploitation of HDR geothermal energy. It has many hidden faults in the reservoir/caprock sequences. Injecting fluid into underground formations during hydraulic fracturing often induces fault slip and leads to earthquakes. Therefore, to well understand the induced fault slip and earthquakes is important for the applications and development of HDR geothermal exploitation. In this study, we investigated the hazardous injection area of the induced earthquakes during hydraulic fracturing. The study was based on a hydraulic fracturing test in Qiabuqia geothermal field in China. According to the field, a fault-surrounding rock-fracturing region system was developed to study the influences of fluid injection on the stability of the specific fault. A total of 60 hydraulic fracturing regions and 180 numerical experiments were designed. The results revealed that the hazardous injection regions that threaten the fault's stability were near to the fault and concentrated on the following four areas: (a) above the top of the fault in underlying strata; (b) above the top of the hanging wall of the fault in underlying strata; (c) near to the fault planes in both footwall and hanging wall; (d) at the bottom of the footwall of the fault in underlying strata. The hazardous injection area can be controlled effectively by adjusting the injection pressure. [ABSTRACT FROM AUTHOR]

Hot dry rock (HDR) geothermal energy has become promising resources for relieving the energy crisis and global warming. The exploitation of HDR geothermal energy usually needs an enhanced geothermal system (EGS) with artificial fracture networks by hydraulic fracturing. Fault reactivation and seismicity induced by hydraulic fracturing raise a great challenge. In this paper, we investigated the characteristics of fault slip and seismicity by numerical simulation. The study was based on a hydraulic fracturing project in the geothermal field of Yishu fault zone in China. It revealed that fluid injection during hydraulic fracturing can cause the faults that exist beyond the fluid-pressurized region to slip and can even induce large seismic event. It was easier to cause felt earthquakes when hydraulic fracturing was carried out in different layers simultaneously. We also examined the effects of the location, permeability, and area of the fracturing region on fault slip and magnitude of the resulting events. The results of the study can provide some useful references for establishing HDR EGS in Yishu fault zone. [ABSTRACT FROM AUTHOR]

The relationship between board interlocks and corporate social responsibility (CSR) has been much debated, and the limited understanding of the heterogeneity of board interlocks is considered a significant reason. Based on resource dependency theory, this study aims to investigate the impact of the heterogeneity resulting from interlocked directors' presence in different industries on CSR. This study used a sample of Chinese-listed companies from 2012 to 2019 and employed multivariate regression analysis models. The empirical results suggested that the industry heterogeneity of board interlocks positively impacts CSR. Furthermore, the impact of industry heterogeneity is more significant in state-owned enterprises (SOEs) or companies that receive greater media attention in the Chinese context. This study contributed to the literature by confirming the importance of industry heterogeneity of board interlocks and provided some managerial implications for companies to promote CSR by selecting specific directors. [Display omitted] • The industry heterogeneity of board interlocks is positively associated with corporate social responsibility. • Ownership nature moderates the industry heterogeneity and corporate social responsibility relationship. • The positive impact of industry heterogeneity of board interlocks on CSR among state-owned enterprises is reinforced. • Media attention positively moderates the industry heterogeneity and corporate social responsibility relationship. [ABSTRACT FROM AUTHOR]

Human behavior analysis is an important area of research in computer vision and is also driven by a wide spectrum of applications, such as smart video surveillance and human-computer interface. In this paper, we present a novel approach for human behavior analysis. Two research challenges, motion representation and behavior recognition, are addressed. A novel motion descriptor, which is an improved feature based on optical flow, is proposed for motion representation. Optical flow is improved with a motion filter, and feature fusion with the shape and trajectory information. To recognize the behavior, the support vector machine is employed to train the classifier where the concatenation of histograms is formed as the input features. Experimental results on the Weizmann behavior database and the Institute of Automation, Chinese Academy of Science real- world multiview behavior database demonstrate the robustness and effectiveness of our method. [ABSTRACT FROM AUTHOR]

Vegetative insecticidal proteins (Vip), the second generation of insecticides, are produced during the vegetative growth stage of Bacillus thuringiensis (Bt). To perform a systematic study of vip genes in Bt strains from different ecological regions of Sichuan Basin, 1,789 soil samples were collected from this basin, which is situated in the western region of China. The basin has a complicated geomorphology and contains mountains, forests, highlands, hursts, and plains. A total of 2,134 Bt strains have been screened from the 1,789 soil samples. According to the results, three vip-type genes were found in this basin, namely the vip1, vip2, and vip3-type genes. Strains containing vip3-type genes were the most abundant in our collection (67.4%), followed by vip2-type genes (14.6%) and vip1-type genes (8.1%). The three types of vip genes were distributed in most of the regions, but E Mei Mountain and the Ba Lang Mountains only contained vip3 genes in environments with high elevation, low temperature, insufficient oxygen, and abundant snow. Moreover, five novel vip3 genes were found, and these Vip proteins were toxic for Chilo suppressalis. All the results mentioned above suggest that Sichuan Basin is a rich resource for vip genes.

We characterized a novel holotype cry gene (cry52Ba1) harbored in a Bacillus thuringiensis isolate BM59-2 native to China that expresses a spherical crystal protein of about 80 kDa. In this study, the full length of the cry52Ba1 gene was cloned from this strain. Sequence analysis of the gene was also performed. Furthermore, cry52Ba1 was expressed in Escherichia coli BL21(DE)pLysS, and the resulting insecticidal activity showed that the Cry52Ba1 protein exhibited high larvicidal activity against Aedes aegypti (Diptera), with a lethal concentration 50 of 1.526 microg/mL (95% confidence: 0.740-3.499 microg/mL).