Study on failure characteristics and control technology of roadway surrounding rock under repeated mining in close-distance coal seam

In this study, taking the Sheng’an coal mine as an engineering background, the failure characteristics of the surrounding rock of a roadway under repeated mining in a close-distance coal seam is comprehensively illustrated through field measurements (e.g., drilling imaging), theory analysis and numerical simulation (finite difference method (FDM)). The results show that although the return airway 10905 remains intact, the apparent failure of the roadway’s roof and the coal pillar can be observed. In addition, the expression of floor failure depth caused by upper coal seam mining is obtained through elastic-plastic theory. Meanwhile, the deformation of the surrounding rock of the roadway increases with the increase of repeated mining times, especially for the horizontal displacement of the roadway on the coal pillar side. Moreover, the cracks’ evolution of surrounding rock in the roadway can be observed as asymmetric characteristics. Finally, the stability control technology of “asymmetric anchor net cable + I-steel” is proposed to prevent potential mining disasters, and the feasibility of this support scheme is verified by numerical simulation and field practices. It can meet the requirement of safe mining and provide guidelines to effectively solve the failure of a roadway in close-distance coal seam mining

A Human-Specific <i>De Novo</i> Protein-Coding Gene Associated with Human Brain Functions

To understand whether any human-specific new genes may be associated with human brain functions, we computationally screened the genetic vulnerable factors identified through Genome-Wide Association Studies and linkage analyses of nicotine addiction and found one human-specific de novo protein-coding gene, FLJ33706 (alternative gene symbol C20orf203). Cross-species analysis revealed interesting evolutionary paths of how this gene had originated from noncoding DNA sequences: insertion of repeat elements especially Alu contributed to the formation of the first coding exon and six standard splice junctions on the branch leading to humans and chimpanzees, and two subsequent substitutions in the human lineage escaped two stop codons and created an open reading frame of 194 amino acids. We experimentally verified FLJ33706's mRNA and protein expression in the brain. Real-Time PCR in multiple tissues demonstrated that FLJ33706 was most abundantly expressed in brain. Human polymorphism data suggested that FLJ33706 encodes a protein under purifying selection. A specifically designed antibody detected its protein expression across human cortex, cerebellum and midbrain. Immunohistochemistry study in normal human brain cortex revealed the localization of FLJ33706 protein in neurons. Elevated expressions of FLJ33706 were detected in Alzheimer's brain samples, suggesting the role of this novel gene in human-specific pathogenesis of Alzheimer's disease. FLJ33706 provided the strongest evidence so far that human-specific de novo genes can have protein-coding potential and differential protein expression, and be involved in human brain functions.</p

A Human-Specific De Novo Protein-Coding Gene Associated with Human Brain Functions

To understand whether any human-specific new genes may be associated with human brain functions, we computationally screened the genetic vulnerable factors identified through Genome-Wide Association Studies and linkage analyses of nicotine addiction and found one human-specific de novo protein-coding gene, FLJ33706 (alternative gene symbol C20orf203). Cross-species analysis revealed interesting evolutionary paths of how this gene had originated from noncoding DNA sequences: insertion of repeat elements especially Alu contributed to the formation of the first coding exon and six standard splice junctions on the branch leading to humans and chimpanzees, and two subsequent substitutions in the human lineage escaped two stop codons and created an open reading frame of 194 amino acids. We experimentally verified FLJ33706's mRNA and protein expression in the brain. Real-Time PCR in multiple tissues demonstrated that FLJ33706 was most abundantly expressed in brain. Human polymorphism data suggested that FLJ33706 encodes a protein under purifying selection. A specifically designed antibody detected its protein expression across human cortex, cerebellum and midbrain. Immunohistochemistry study in normal human brain cortex revealed the localization of FLJ33706 protein in neurons. Elevated expressions of FLJ33706 were detected in Alzheimer's brain samples, suggesting the role of this novel gene in human-specific pathogenesis of Alzheimer's disease. FLJ33706 provided the strongest evidence so far that human-specific de novo genes can have protein-coding potential and differential protein expression, and be involved in human brain functions

Multiple Equilibrium Behaviors considering Human Exposure to Vehicular Emissions

Emissions produced by urban transportation activities are harmful to people’s health and they also affect people’s trip-making decisions. In this paper, we explore the multiple equilibrium behaviors considering human exposure to vehicular emissions. We assume that a portion of transportation users are environmental advocates and their route decisions are based on some composite cost functions comprise of a travel time component and an emission exposure component. We then study the multiple equilibrium behaviors with multiple types of users on a traffic network. The multiple equilibrium problems are further converted into variational inequality (VI) problems and they are solved using a method of successive average- (MSA-) based diagonalization method. Per the specific network setting, we find that as travelers become more concerned about their exposure to vehicular emissions, the system emission exposure, travel time, and the total cost get reduced; i.e., Pareto improving solutions are achieved. By analyzing the multiple equilibrium behaviors, we find that the system gets better if more users become environmental advocates. And the change of a small percentage of users should already lead to a good system improvement

Effect of intersphincteric fistula tract ligation versus anal fistulectomy on pain scores and serum levels of vascular endothelial growth factor and interleukin-2 in patients with simple anal fistulas

Objective This study was performed to explore the effects of ligation of the intersphincteric fistula tract (LIFT) on pain scores and serum levels of vascular endothelial growth factor (VEGF) and interleukin (IL)-2 in patients with simple anal fistulas. Methods Ninety patients with simple anal fistulas were evenly randomized into a study group (treated with LIFT) and a control group (treated with traditional anal fistulectomy) according to a random number table. The surgical outcomes, basic operation conditions (operation time, hospital stay, and anal continence), and postoperative wound healing rates were compared between the two groups. Results The study group had significantly better operation conditions (better anal continence and shorter length of hospital stay), a higher postoperative wound healing rate, lower pain scores, higher VEGF and IL-2 levels, and higher overall efficacy rate than the control group. However, the incidence of postoperative complications was not significantly different between the two groups. Conclusions Patients who underwent LIFT had better surgical outcomes, higher wound healing rates, better anal continence, a shorter length of hospital stay, and less severe postoperative pain than those who underwent simple anal fistulectomy. Increased levels of VEGF and IL-2 after surgery may promote wound healing

Instability Control of Roadway Surrounding Rock in Close-Distance Coal Seam Groups under Repeated Mining

In order to solve the problems of roadway stability and easy instability under repeated mining of close-distance coal seam groups, the mechanism and control technology of surrounding rock instability under repeated mining were studied via indoor testing, field testing, physical similarity simulation experiment, and numerical simulation. The results show that the surrounding rock of roadway has low strength, low bearing capacity, and poor self-stabilization ability, and it is vulnerable to engineering disturbances and fragmentation. Affected by the disturbance under repeated mining, the roadway surrounding rock cracks are developed and the sensitivity is strong, and it is prone to large-scale loose and destroyed. The location of the roadway is unreasonable, and the maximum principal stress of the roadway is 3.1 times of the minimum principal stress, which is quite different. Thus, under a large horizontal stress, the surrounding rock undergoes long-range expansion deformation. On the basis of this research, the direction and emphasis of stability control of roadway surrounding rock under repeated mining of coal seam groups in close-distance are shown. A repair scheme (i.e., long bolt + high-strength anchor cable + U-shaped steel + grouting) is proposed, and reduces the risk of roadway instability

Opposite Root Morphological Responses of Chinese Cabbage to Poly-γ-glutamic Acid When Applied with Urea and Ammonium Sulphate

Poly-γ-glutamic acid (γ-PGA) significantly promotes the fertilizer N uptake efficiency of crops and evidently affects soil available N (nitrate, ammonium and glutamate) status. As an adaptive strategy to forage N, root morphology responds variably to soil available N dynamics. Detailed knowledge of how root morphology responds to γ-PGA remains unexplored. A pot trial was conducted to investigate the response of root morphological traits to γ-PGA when applied with CO(NH2)2 or (NH4)2SO4. The results showed that γ-PGA significantly improved the dry weight, total carbon and total nitrogen content of roots, and with a higher improvement with CO(NH2)2 compared to (NH4)2SO4. γ-PGA significantly increased the root length, total surface area, tips and forks with CO(NH2)2. Contrarily, γ-PGA significantly reduced root length, specific root length, specific root area, root volume, tips and forks with (NH4)2SO4, with its inhibition on root growth mainly caused by the high ammonium content in soil. In conclusion, γ-PGA gives opposite effects on root morphological traits when applied with CO(NH2)2 or (NH4)2SO4. This finding provides a new insight to reveal the promotion mechanism of γ-PGA on plant N acquisition in the rhizosphere and offers a practical reference for optimizing γ-PGA and fertilizer application management