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The transverse thermoelectric effect based on the anomalous Nernst effect (ANE) has attracted attention, especially for thermoelectric and spintronic applications. Fe 3 X (X = Ga, Al) is known to exhibit a large ANE at room temperature owing to the topological electronic band structure so-called nodal web. Here, we systematically investigate ANE in the polycrystalline Fe3Ga1−xAlx and Fe3Al1−xSix. Despite significant chemical substitutions, a very robust feature of the large ANE − S y x ∼ 5.7 μ V/K is found for Fe3Ga1−xAlx (0 ≲ x ≲ 0.6), exhibiting a striking x independent nodal web contribution. Since aluminum is more low-cost and abundant than gallium, our results indicate Fe3Ga1−xAlx (x ∼ 0.6) should be suitable for large-scale thermoelectric applications. [ABSTRACT FROM AUTHOR]

MicroRNA (miRNA) biogenesis is known to be modulated by a variety of RNA-binding proteins (RBPs), but in most cases, individual RBPs appear to influence the processing of a small subset of target miRNAs. Here, we report that the RNA-binding NONO-PSF heterodimer binds a large number of expressed pri-miRNAs in HeLa cells to globally enhance pri-miRNA processing by the Drosha-DGCR8 Microprocessor. NONO and PSF are key components of paraspeckles organized by the long noncoding RNA (lncRNA) NEAT1. We further demonstrate that NEAT1 also has a profound effect on global pri-miRNA processing. Mechanistic dissection reveals that NEAT1 broadly interacts with the NONO-PSF heterodimer as well as many other RBPs and that multiple RNA segments in NEAT1, including a 'pseudo pri-miRNA' near its 3' end, help attract the Microprocessor. These findings suggest a 'bird nest' model in which an lncRNA orchestrates efficient processing of potentially an entire class of small noncoding RNAs in the nucleus.

Thermoelectric generation using the anomalous Nernst effect (ANE) has great potential for application in energy harvesting technology because the transverse geometry of the Nernst effect should enable efficient, large-area and flexible coverage of a heat source. For such applications to be viable, substantial improvements will be necessary not only for their performance but also for the associated material costs, safety and stability. In terms of the electronic structure, the anomalous Nernst effect (ANE) originates from the Berry curvature of the conduction electrons near the Fermi energy.sup.1,2. To design a large Berry curvature, several approaches have been considered using nodal points and lines in momentum space.sup.3-10. Here we perform a high-throughput computational search and find that 25 percent doping of aluminium and gallium in alpha iron, a naturally abundant and low-cost element, dramatically enhances the ANE by a factor of more than ten, reaching about 4 and 6 microvolts per kelvin at room temperature, respectively, close to the highest value reported so far. The comparison between experiment and theory indicates that the Fermi energy tuning to the nodal web--a flat band structure made of interconnected nodal lines--is the key for the strong enhancement in the transverse thermoelectric coefficient, reaching a value of about 5 amperes per kelvin per metre with a logarithmic temperature dependence. We have also succeeded in fabricating thin films that exhibit a large ANE at zero field, which could be suitable for designing low-cost, flexible microelectronic thermoelectric generators.sup.11-13. Aluminium- and gallium-doped iron compounds show a large anomalous Nernst effect owing to a topological electronic structure, and their films are potentially suitable for designing low-cost, flexible microelectronic thermoelectric generators., Author(s): Akito Sakai [sup.1] [sup.2] [sup.3] , Susumu Minami [sup.4] [sup.5] , Takashi Koretsune [sup.6] , Taishi Chen [sup.1] [sup.3] , Tomoya Higo [sup.1] [sup.3] , Yangming Wang [sup.1] , [...]

To investigate the mechanism of reinforcing soft soil with cement-mixing pile, based on ABAQUS secondary development, a numerical simulation study of the hydration reaction of cement-mixing piles was conducted. In this study, the influence of ground temperature variations on the distribution patterns of the temperature field in and around the pile was also considered. The temperature field of the pile–soil model can be primarily divided into two stages: the temperature rise stage (0~5 d) and the temperature decrease stage (5~90 d). The following observations were made: (1) The temperature of the pile body rapidly increased within the first 5 days, dissipating heat to the surrounding soil, leading to an elevation of the temperature in the soil around the pile and a decrease in soil moisture content. Around the 5th day, the temperature reached its maximum value, and the heat release rate of the pile body was higher than that of the surrounding soil. (2) With a 15% cement admixture, under the influence of 425# cement hydration, the temperature inside the pile increased by 5 °C, and the temperature in the soil around the pile increased by 4.2 °C. After considering the ground temperature, the temperature in the soil around the pile increased by 4.6 °C. (3) The maximum temperature generated during the hydration of 425# Portland cement is higher than that of 525#; the temperature of the soil around piles made with 425# cement is consistently higher than that made with 525#. (4) The hydration temperature of piles with a 10% cement admixture increased by 4.4 °C; for piles with a 15% cement admixture, the hydration temperature increased by 6.6 °C; and for piles with a 20% cement admixture, the hydration temperature increased by 9.1 °C. The temperature field of this structure gradually stabilizes after 7 days with increasing time and cement admixture. The results indicate that the hydration of cement-mixing piles raises the temperature of the soil around the piles. Additionally, the temperature resulting from the hydration of cement-mixing pile increases with the addition of cement. [ABSTRACT FROM AUTHOR]

The miR-294 and miR-302 microRNAs promote the abbreviated G1 phase of the embryonic stem cell (ESC) cell cycle and suppress differentiation induced by let-7. Here, we evaluated the role of the retinoblastoma (Rb) family proteins in these settings. Under normal growth conditions, miR-294 promoted the rapid G1-S transition independent of the Rb family. In contrast, miR-294 suppressed the further accumulation of cells in G1 in response to nutrient deprivation and cell-cell contact in an Rb-dependent fashion. We uncovered five additional miRNAs (miR-26a, miR-99b, miR-193, miR-199a-5p, and miR-218) that silenced ESC self-renewal in the absence of other miRNAs, all of which were antagonized by miR-294 and miR-302. Four of the six differentiation-inducing miRNAs induced an Rb-dependent G1 accumulation. However, all six still silenced self-renewal in the absence of the Rb proteins. These results show that the miR-294/miR-302 family acts through Rb-dependent and -independent pathways to regulate the G1 restriction point and the silencing of self-renewal, respectively.

SUMMARY: The regulated biosynthesis of chlorophyll is important because of its effects on plant photosynthesis and dry biomass production. In this study, a map‐based cloning approach was used to isolate the cytochrome P450‐like gene BnaC08g34840D (BnCDE1) from a chlorophyll‐deficient mutant (cde1) of Brassica napus obtained by ethyl methanesulfonate (EMS) mutagenization. Sequence analyses revealed that BnaC08g34840D in the cde1 mutant (BnCDE1I320T) encodes a substitution at amino acid 320 (Ile320Thr) in the conserved region. The over‐expression of BnCDE1I320T in ZS11 (i.e., gene‐mapping parent with green leaves) recapitulated a yellow‐green leaf phenotype. The CRISPR/Cas9 genome‐editing system was used to design two single‐guide RNAs (sgRNAs) targeting BnCDE1I320T in the cde1 mutant. The knockout of BnCDE1I320T in the cde1 mutant via a gene‐editing method restored normal leaf coloration (i.e., green leaves). These results indicate that the substitution in BnaC08g34840D alters the leaf color. Physiological analyses showed that the over‐expression of BnCDE1I320T leads to decreases in the number of chloroplasts per mesophyll cell and in the contents of the intermediates of the chlorophyll biosynthesis pathway in leaves, while it increases heme biosynthesis, thereby lowering the photosynthetic efficiency of the cde1 mutant. The Ile320Thr mutation in the highly conserved region of BnaC08g34840D inhibited chlorophyll biosynthesis and disrupted the balance between heme and chlorophyll biosynthesis. Our findings may further reveal how the proper balance between the chlorophyll and heme biosynthesis pathways is maintained. Significance Statement: Genetic changes in the chlorophyll biosynthesis pathway may affect plant photosynthesis and dry biomass production, and the genetic and molecular mechanisms of leaf‐color variations are complex. We found a novel CYP705 family gene (BnCDE1I320T) of cytochrome P450 superfamily affected the contents of chlorophyll intermediates and heme to control the leaf color by map‐based cloning and genetic transformation experiments in Brassica napus. [ABSTRACT FROM AUTHOR]