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Paulownia fortunei, one of the world's fastest growing timber tree species, is universally applied with fertilizer as a management approach to meet the nutrient requirements for efficient cultivation. The substantial effects of fertilizer on soil microorganisms in Paulownia plantations have been empirically tested; however, the successive chronosequence of soil microbial carbon and nitrogen functional genes under different fertilizer application durations remains limited. The objective of this study was to explore the characteristics of soil microorganisms involved in carbon and nitrogen cycling and greenhouse gas (GHG) production under different fertilizer application durations. Different fertilizer treatments, i.e., the short-term group (SG) versus the long-term group (LG), and durations were applied to subtropical plantations in southern China and compared with zonal evergreen broad-leaved forests. Results showed that fertilizer treatment significantly increased the relative abundance of Acidobacteriota and the expression of nirK and nosZ. The functional groups that dominated metabolism in SG and LG treatments belonged to Actinobacteria and Acidobacteriota, respectively, suggesting that the nutrient preference of microorganisms in forest soil may change from copiotrophs to oligotrophs with increasing fertilizer application duration. Correlation network analysis showed that the communities that dominated the carbon and nitrogen cycles belonged to Actinobacteria and Acidobacteriota, respectively, and were closely related to ammonium nitrogen and available iron. Actinobacteria and Acidobacteriota were likely the major taxa that affected soil GHG production under different fertilizer application durations. We concluded that long-term fertilizer use changed the preference of microbial nutrient uptake into recalcitrant nutrients, and the sensitivity of the microbial community to nutrients gradually decreased with increasing fertilizer application time. The dominant Actinobacteria affected soil carbon and nitrogen cycles largely by stimulating denitrification to increase the release of nitrous oxide, which might lead to the loss of nitrogen components and the intensification of the GHG effect with increasing fertilizer application time. [ABSTRACT FROM AUTHOR]

Casing deformation occurs frequently in shale gas wells, resulting in the failure of some fracturing stages to complete normal operations, which seriously affects shale gas production. This paper firstly analyzes the casing deformation mechanism of shale gas wells and determines that the casing shear deformation caused by formation slip is the main factor of casing deformation. In order to solve the problem of casing shear deformation, a finite element numerical model including the formation, cement ring, and the casing is established. The casing shear deformation caused by formation slip is simulated, and the deformation results obtained are consistent with those measured in the actual wellbore. Based on the numerical model, a casing deformation governance method is proposed to optimize the wellbore trajectory and adjust the cement ring properties. It is calculated that reducing the dip angle á of the formation and casing vertical direction and reducing the formation slip is beneficial to reducing casing deformation. The use of low elastic modulus cement and uncementing operations can provide a buffer space for formation slip, effectively reduce casing deformation, and provide an effective treatment method for shear deformation of shale gas wells. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) paradigm, by transforming physical devices into innovative items, affects every aspect of our daily lives. It has brought a slew of evolutionary and revolutionary services that were almost impossible to imagine until recently. The numerous services and applications offered by IoT cover numerous fields, such as personal healthcare, urban life, energy management, and manufacturing. A tremendous amount of data is produced to reach valuable information and meet users' needs. In addition, since the number of services and applications is increasing rapidly, an efficient method to fulfill the growing demands in different application domains becomes challenging. To handle the mentioned problems, task scheduling mechanisms have a significant influence. Despite the importance of these methods in the IoT, an in-depth and systematic review of the current works in this area is clearly lacking. Therefore, we aim to overcome this gap by adopting an organized manner. In fact, this paper aims to specify the challenging problems in IoT task scheduling, highlight the effective works, and outline some hints for upcoming studies. [ABSTRACT FROM AUTHOR]