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There is a high potential for coal spontaneous combustion (CSC) above the roof beams of supports during the mining-stopped period. Early detection of temperature abnormal zones and corresponding measures are necessary to prevent CSC. In this work, a top-coal temperature measurement method was proposed, combining the coal surface temperature detection and the drilling temperature observation. Furthermore, an apparatus was developed that dramatically increases the rate of dry ice sublimation, resulting in the rapid release of cryogenic carbon dioxide gas. The device utilizes water from firefighting pipes in underground coal mines as a heat source for dry ice sublimation without electrical energy and has been applied and validated taking Silaogou Coal Mine in China as a field test site. Specifically, we found that during the stoppage period, the coal above the supports near the air inlet tunnel is more likely to appear hot spots; the carbon dioxide gas generated by the dry ice phase change device can quickly reduce the hot spots temperature, and the coal temperature does not rebound after the gas injection is stopped. Based on the above analysis, this work can effectively prevent the early top-coal spontaneous combustion during the stop mining period. [ABSTRACT FROM AUTHOR]

Fucoxanthin and eicosapentaenoic acid (EPA) are high-value compounds that can be found in the marine diatom Phaeodactylum tricornutum. Yet, the growth rate of this microalga is relatively low under photoautotrophic conditions. The purpose of this study was to evaluate the feasibility of using spent yeast, the second-major by-product of the brewing industry, as a useful substrate for P. tricornutum cultivation. Different pretreatments, concentrations of spent yeast, and initial cell densities of P. tricornutum were investigated. After 12 days of cultivation in f/2 medium, P. tricornutum supplemented with 1.33 g L−1 preautoclaved spent yeast yielded 3.28 times more fucoxanthin (5.97 mg L−1) and 3.55 times more EPA (16.82 mg L−1) than P. tricornutum grown without the yeast (fucoxanthin 1.82 mg L−1, EPA 4.64 mg L−1). Nutrient analysis showed that the nitrogen and phosphorus released by the spent yeast were consumed over time. Overall, spent yeast effectively promoted the fucoxanthin and EPA yields of P. tricornutum. [ABSTRACT FROM AUTHOR]

Chlamydomonas reinhardtii is a photosynthetic unicellular model algae with multiple biotechnological advantages, and its fatty acids can be used to produce biofuels. Numerous studies suggest that acetyl-coA carboxylase (ACCa) catalyzes the first committed and rate-limiting step of fatty acid biosynthesis, thereby playing a central role in oil accumulation. Here, we cloned and overexpressed ACCa in C. reinhardtii to directly evaluate its effect on fatty acid synthesis. GC–MS analysis found that the unsaturated FAs contents of the CW15-24 and CW15-85 strains were 55.45% and 56.15%, which were significantly enriched compared to the wild type CW15 (48.39%). Under the optimized conditions, the content of lipid by overexpressed the ACCa gene in the mutant CW15-85 (0.46 g/l) was 1.16-fold greater than control through optimization of N and P sources. Altogether, our data clearly demonstrate that ACCa overexpression in C. reinhardtii can directly increase the synthesis of fatty acids. [ABSTRACT FROM AUTHOR]

Transcription of the gene coding for glycerol-3-phosphate dehydrogenase (GPD1) was repressed in an industrial strain of Saccharomyces cerevisiae using a silencing vector. A fusion fragment containing GPD1 and Kan MX genes was generated by overlap extension PCR, then, the vector, pYES2.0 GPD1/Kan MX, was constructed by inserting the fusion fragment into the S. cerevisiae plasmid, pYES2.0. pYES2.0 GPD1/Kan MX, was linearized by KpnI, transformed into S. cerevisiae using the PEG/LiAc/ssDNA method, and integrated into the S. cerevisiae chromosome. GPD1 silencing gave 20 % less glycerol-3-phosphate dehydrogenase activity, 19 % lower glycerol production, and 9.7 % higher ethanol production compared with the original strain. These findings further the development of industrial S. cerevisiae strains with improved ethanol production and reduced glycerol content for the efficient production of bio-ethanol. [ABSTRACT FROM AUTHOR]

To improve the fermentation yield of xylanase by optimizing the fermentation conditions for strain Xw2, a Plackett-Burman design was used to evaluate the effects of eight variables on xylanase production by strain Xw2. The steepest ascent (descent) method was used to approach the optimal response surface experimental area. The optimal fermentation conditions were obtained by central composite design and response surface analysis. The results showed that the composition of the optimal fermentation medium was corn cob + 1.5% wheat bran (1:1), 0.04% MnSO 4, 0.04% K 2HPO 4·3H 2O, and an inoculum size of 6% in 50 mL liquid volume (pH = 6.0). The optimal culture conditions were 28°C at 150 r/min for 54.23 h. The results of this study can serve as the basis for the industrial production and application of xylanase. [ABSTRACT FROM AUTHOR]

We determined the variation tendency of viscosity ( η) at various solids loading ( ϕ) for 3Y-TZP suspension as a function of dispersant concentration ( Cw) using viscosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sediment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dispersing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the ( Cw, η), ( Cw, ϕ), and ( ϕ, η) two-parameter, and ( Cw, ϕ, η) three-parameter stability maps were constructed. Based on the DLVO theory calculations, the dispersant concentration, particle distance ( r), and interparticle potential energy ( V T ) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In ( Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, ϕ, and V T,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, V T maps introduced above. The ( Cw, ϕ) two-parameter stability map was then obtained from the Cw, ϕ, V T,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parameter—were reasonable. [ABSTRACT FROM AUTHOR]

Pufferfish are ideal models for vertebrate chromosome evolution studies. The yellowbelly pufferfish, Takifugu flavidus, is an important marine fish species in the aquaculture industry and ecology of East Asia. The chromosome assembly of the species could facilitate the study of chromosome evolution and functional gene mapping. To this end, 44, 27 and 50 Gb reads were generated for genome assembly using Illumina, PacBio and Hi-C sequencing technologies, respectively. More than 13 Gb full-length transcripts were sequenced on the PacBio platform. A 366 Mb genome was obtained with the contig of 4.4 Mb and scaffold N50 length of 15.7 Mb. 266 contigs were reliably assembled into 22 chromosomes, representing 95.9% of the total genome. A total of 29,416 protein-coding genes were predicted and 28,071 genes were functionally annotated. More than 97.7% of the BUSCO genes were successfully detected in the genome. The genome resource in this work will be used for the conservation and population genetics of the yellowbelly pufferfish, as well as in vertebrate chromosome evolution studies. Measurement(s) whole genome sequencing assay • transcription profiling assay • sequence_assembly • sequence annotation Technology Type(s) DNA sequencing • RNA sequencing assay • genome assembly • bioinformatics analysis Sample Characteristic - Organism Takifugu flavidus Sample Characteristic - Environment aquatic environment Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.10008740 [ABSTRACT FROM AUTHOR]

Bioethanol, as a form of renewable and clean energy, has become increasingly important to the energy supply. One major obstacle in ethanol production is developing a high-capacity system. Existing approaches for regulating the ethanol production pathway are relatively insufficient, with nonspecific genetic manipulation. Here, we used CRISPR/Cas9 technology to disrupt the alcohol dehydrogenase (ADH) 2 gene via complete deletion of the gene and introduction of a frameshift mutation in the ADH2 locus. Sequencing demonstrated the accurate knockout of the target gene with 91.4% and near 100% targeting efficiency. We also utilized genome resequencing to validate the mutations in the ADH2 mutants targeted by various single-guide RNAs. This extensive analysis indicated the mutations in the CRISPR/Cas9-engineered strains were homozygous. We applied the engineered Saccharomyces cerevisiae strains for bioethanol production. Results showed that the ethanol yield improved by up to 74.7% compared with the yield obtained using the native strain. This work illustrates the applicability of this highly efficient and specific genome engineering approach to promote the improvement of bioethanol production in S. cerevisiae via metabolic engineering. Importantly, this study is the first report of the disruption of a target gene, ADH2, in S. cerevisiae using CRISPR/Cas9 technology to improve bioethanol yield. [ABSTRACT FROM AUTHOR]