In situ replacement of a failed implant to rescue a complete arch fixed prosthesis: A dental technique.

Implant failure may occur after the delivery of definitive prostheses. Avoiding replacement of a complete arch implant-supported fixed prosthesis becomes a significant challenge when placement of a new implant is necessary. This technical article introduces a protocol to replace a failed implant in situ, effectively rescuing the original prosthesis.

A dental technique to reseat an angled nonhexagon multiunit abutment in a complete arch fixed prosthesis.

When an angled abutment lacking an antirotation structure within a complete arch implant- supported fixed prosthesis becomes loose, the conventional approach typically involves replacing the entire prosthesis because of the difficulty of reseating the abutment at its original angle. To address this predicament, this technique article describes a novel solution in the form of a resin verification guide that replicates the maxillary prosthesis. The modified cylinder enables tightening of the abutment screw of the reseated multiunit abutment in place, eliminating the need for replacing the prosthesis and reducing treatment costs and duration.

A new strategy for the enrichment of ammonia-oxidizing archaea in wastewater treatment systems: The positive role of quorum-sensing signaling molecules.

Ammonia-oxidizing archaea (AOA) play an important role in natural nitrogen cycle, but are difficult to be enriched in wastewater treatment systems. In this experiment, under ambient temperature and high dissolved oxygen, different types of acyl-homoserine lactones (C6-HSL, C8-HSL, C10-HSL, C14-HSL and 3-oxo-C14-HSL) were added to five wastewater nitrification systems to achieve AOA enrichment. Results showed that AOA couldn't be detected in the blank group without the addition of signaling molecules, while the AOA could be detected in all the reactors with the addition. The enrichment effect of AOA was not obvious with added 100 or 200 nmol/L signaling molecules, while the enrichment effect was both obvious with added C8-HSL of 400 nmol/L and C10-HSL of 800 nmol/L. And relative abundance of AOA increased from undetected in the control group to 1.10 % and 0.96 %, respectively. The exogenous signaling molecules may provide new view for AOA enrichment in wastewater treatment systems.

Immune Responses and Transcriptomic Analysis of Nilaparvata lugens against Metarhizium anisopliae YTTR Mediated by Rice Ragged Stunt Virus.

Plant viruses and entomopathogenic fungi (EPF) can both elicit immune responses in insects. This study was designed to clarify whether plant viruses could affect the efficacy of EPF and explore the immune responses of brown planthopper (BPH), Nilaparvata lugens, in response to different pathogen infections. In this study, a strain of Metarhizium anisopliae YTTR with high pathogenicity against BPH was selected and explored whether rice ragged stunt virus (RRSV) could affect its lethality against BPH. RNA-seq was used to detect the inner responses of BPH in response to RRSV and M. anisopliae YTTR infection. Results showed that M. anisopliae YTTR has strong lethality against BPH (RRSV-carrying and RRSV-free). RRSV invasion did not affect the susceptibility of BPH against M. anisopliae YTTR at all concentrations. At 1 × 108 spores/mL, M. anisopliae YTTR caused a cumulative mortality of 80% to BPH at 7 days post-treatment. The largest numbers of differentially expressed genes (DEGs) was obtained in BPH treated with the two pathogens than in other single pathogen treatment. In addition, KEGG enrichment analysis showed that the DEGs were mostly enriched in immune and physiological mechanisms-related pathways. Both RRSV and M. anisopliae YTTR could induce the expression changes of immune-related genes. However, most of the immune genes had varying expression patterns in different treatment. Our findings demonstrated that RRSV invasion did not have any significant effect on the pathogenicity of M. anisopliae YTTR, while the co-infection of M. anisopliae YTTR and RRSV induced more immune and physiological mechanisms -related genes' responses. In addition, the presence of RRSV could render the interplay between BPH and M. anisopliae YTTR more intricate. These findings laid a basis for further elucidating the immune response mechanisms of RRSV-mediated BPH to M. anisopliae infection.

Hazardous Area Reconstruction and Law Analysis of Coal Spontaneous Combustion and Gas Coupling Disasters in Goaf Based on DEM-CFD.

Coal spontaneous combustion and gas coupling disasters are the highest percentage of serious accidents in coal mines, causing the most serious disasters. China is one of the countries with the most serious coal spontaneous combustion and gas coupling disasters in goaf, and it is of great significance to explore the evolution law of coal spontaneous combustion and gas coupling disasters in goaf for disaster prevention and control. To study the three-dimensional spatial characteristics of the hazardous area of the coupling coal spontaneous combustion and gas disaster in goaf, a discrete element method-computational fluid dynamics (DEM-CFD)-based hazardous area reconstruction method was proposed. Taking a fully mechanized caving face of a coal mine in Shandong, China, as an example, first, the working face mining model was established by PFC3D, and the porosity of different horizontal and vertical positions of goaf after mining was extracted. Second, the porosity extracted was imported into computational fluid simulation software FLUENT by UDF. Finally, the distribution laws of oxygen and gas concentration during the real goaf mining process were simulated and analyzed. The results showed that the oxygen concentration in the intake roadway at a depth of 50.7 m in goaf decreased to 12%, and the gas concentration at a depth of 42.0 m in goaf increased to 16%. The oxygen concentration in the return airway roadway was reduced to 12% at 17.3 m depth in goaf, and the gas concentration increased to 16% at 6 m in the direction of goaf. The gas concentration was higher at the return air corner. The three-dimensional shapes of the hazardous area in goaf were constructed to satisfy the coupling of O2 concentration field, CH4 explosion limit concentration field, and fracture field and so were the laws of hazardous area analyzed qualitatively and quantitatively. It has important research significance for the rapid identification and determination of the coal spontaneous combustion and gas coupling disasters hazardous area.