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Thermoelectric transport, i.e., charge current driven by a temperature gradient (Seebeck effect) and heat current driven by an electric current (Peltier effect), provides fundamental insights on microscopic thermodynamics and kinetics of materials and enables devices that convert between heat and electrical work. The ionic Seebeck effect in ionic thermoelectric materials was reported more than one century ago while the reciprocal phenomenon, the ionic Peltier effect, remains unexplored due to experimental challenges. This work reports experimental observations and quantitative measurements of the ionic Peltier effect by an ultrasensitive temperature difference metrology (UTDM) with an extremely high temperature difference resolution up to 4 uK. UTDM enables the probing of sub-mK-level temperature responses of ionic Peltier effect even in the presence of parasitic Joule heat. We observe high ionic Peltier coefficients (up to 450 mV) in liquid electrolytes commonly used in Li-ion batteries. These high Peltier coefficients are approximately one order of magnitude greater than the Peltier coefficients of well-optimized electronic thermoelectric materials and comparable to Peltier coefficients of lightly doped silicon. Our work provides a platform to study the microscopic physics of ionic Peltier effect and understanding the thermodynamics and kinetics of ion transport in Li-ion batteries.

Background: Interleukin (IL)-18 is produced mainly in the heart and can be associated with the development of cardiac hypertrophy that leads to cardiac dysfunction. However, the effects of hypoxia on IL-18 expression and atrial natriuretic factor (ANF) secretion remain largely unknown. Aim: The aim of this study was to assess the effect of hypoxia on IL-18 production and its role in ANF secretion by using an isolated perfused beating rat atrial model. Methods: The level of ANF in the perfusates was determined by radioimmunoassay, and the protein levels of Src, IL-18 and its receptors (IL-18-Rα and IL-18-Rβ), Rho guanine nucleotide exchange factor (RhoGEF) and RhoA, activating transcription factor 3 (ATF3), T cell factor (TCF) 3 and 4, and lymphoid enhancer factor (LEF) 1 in atrial tissue samples were detected by Western blotting. Results: Hypoxia significantly upregulated the expression of the non-receptor tyrosine kinase Src, and this effect was blocked by endothelin-1 receptor type A (BQ123) and type B (BQ788) antagonists. Hypoxia also enhanced the expression of RhoGEF and RhoA concomitantly with the upregulation of IL-18, IL-18-Rα and IL-18-Rβ. The hypoxia-induced RhoGEF and RhoA were abolished by Src inhibitor 1 (SrcI), and the protein levels of IL-18 and its two receptors were also blocked by SrcI. Moreover, the hypoxia-induced expression levels of ATF3, TCF3, TCF4 and LEF1 were repealed by IL-18 binding protein, and the hypoxia-promoted secretion of ANF was also obviously attenuated by this binding protein. Conclusions: These findings imply that Src-IL-18 signaling is involved in the release of ANF in hypoxic beating rat atria.

beta-Ga2O3 is a wide bandgap semiconductor with electrical properties better than SiC and GaN which makes it promising for applications of next-generation power devices. However, the thermal conductivity of \b{eta}-Ga2O3 is more than one order of magnitude lower than that of SiC and GaN, resulting in serious thermal management problems that limit device performance and reliability. This work reports selectively transferring of high thermal conductivity 3C-SiC thin film grown on Si to beta-Ga2O3 (001) substrate using surface activated bonding (SAB) technique at room temperature, to attempt extracting the heat from the surface of the devices. A 4.5-nm-thick interfacial crystal defect layer is formed at the as-bonded 3C-SiC/beta-Ga2O3 interface. The thickness of the interfacial crystal defect layer decreases with increasing annealing temperature, which decreases to 1.5 nm after annealing at 1000 C. No voids and unbonded area are observed at the interfaces, even after annealing at temperature as high as 1000 C. The thermal boundary conductance (TBC) of the 1000 C-annealed 3C-SiC/beta-Ga2O3 interface and thermal conductivity of the beta-Ga2O3 substrate was measured by time-domain thermoreflectance (TDTR). The 3C-SiC/beta-Ga2O3 TBC value was determined to be 244 MW/m2-K, which is the highest value ever reported for SiC/Ga2O3 interfaces, due to the high-quality heterointerface. Our works demonstrate that selective transferring of 3C-SiC film to the beta-Ga2O3 substrate is an efficient path to improve heat dissipation of the \b{eta}-Ga2O3 power devices.

Mechanical degrees of freedom, which have often been overlooked in various quantum systems, have been studied for applications ranging from quantum information processing to sensing. Here, we develop a hybrid platform consisting of a magnomechanical cavity and an optomechanical cavity, which are coherently coupled by the straightway physical contact. The phonons in the system can be manipulated either with the magnetostrictive interaction or optically through the radiation pressure. Together with mechanical state preparation and sensitive readout, we demonstrate the microwave-to-optical conversion with an ultrawide tuning range up to 3 GHz. In addition, we observe a mechanical motion interference effect, in which the optically driven mechanical motion is canceled by the microwave-driven coherent motion. Manipulating mechanical oscillators with equal facility through both magnonic and photonic channels enables new architectures for signal transduction between the optical, microwave, mechanical, and magnetic fields.

The damage effect of PTFE/Al/W reactive fragment impacting partially-filled fuel tank is investigated by combining the ballistic gun experiment and theoretical analysis. The experimental results show that, with the impact velocity ranging from 806m/s to 1331m/s, the reactive fragments successfully perforate the front plate of fuel tank and cause the flash-ignition of fuel/air mixture, but the fuel tank does not fail obviously. Based on the experimental results, a temperature analysis model of reactive debris is developed by combining the energy release characteristic of reactive material and the convective heat transfer model. The model result shows that the high-temperature reactive debris can effectively ignite fuel/air mixture, which is in good agreement with the experimental results.

Background Intensive evidence has highlighted the effect of aberrant alternative splicing (AS) events on cancer progression when triggered by dysregulation of the SR protein family. Nonetheless, the underlying mechanism in breast cancer (BRCA) remains elusive. Here we sought to explore the molecular function of SRSF1 and identify the key AS events regulated by SRSF1 in BRCA. Methods We conducted a comprehensive analysis of the expression and clinical correlation of SRSF1 in BRCA based on the TCGA dataset, Metabric database and clinical tissue samples. Functional analysis of SRSF1 in BRCA was conducted in vitro and in vivo. SRSF1-mediated AS events and their binding motifs were identified by RNA-seq, RNA immunoprecipitation-PCR (RIP-PCR) and in vivo crosslinking followed by immunoprecipitation (CLIP), which was further validated by the minigene reporter assay. PTPMT1 exon 3 (E3) AS was identified to partially mediate the oncogenic role of SRSF1 by the P-AKT/C-MYC axis. Finally, the expression and clinical significance of these AS events were validated in clinical samples and using the TCGA database. Results SRSF1 expression was consistently upregulated in BRCA samples, positively associated with tumor grade and the Ki-67 index, and correlated with poor prognosis in a hormone receptor-positive (HR+) cohort, which facilitated proliferation, cell migration and inhibited apoptosis in vitro and in vivo. We identified SRSF1-mediated AS events and discovered the SRSF1 binding motif in the regulation of splice switching of PTPMT1. Furthermore, PTPMT1 splice switching was regulated by SRSF1 by binding directly to its motif in E3 which partially mediated the oncogenic role of SRSF1 by the AKT/C-MYC axis. Additionally, PTPMT1 splice switching was validated in tissue samples of BRCA patients and using the TCGA database. The high-risk group, identified by AS of PTPMT1 and expression of SRSF1, possessed poorer prognosis in the stage I/II TCGA BRCA cohort. Conclusions SRSF1 exerts oncogenic roles in BRCA partially by regulating the AS of PTPMT1, which could be a therapeutic target candidate in BRCA and a prognostic factor in HR+ BRCA patient.

As an emerging industry formed by the integration of multiple industries, the e-sports industry contributes to urban development, economic growth, and promotion of urban image owing to the characteristics of low pollution, strong driving effect, and high social influence. However, the e-sport industry is a new industry with limited studies about the general features, evolutionary mechanism, and spatial dynamics. As an e-sports industry center in China, Shanghai has the most complete e-sports industry chain and the largest industrial scale. This study takes Shanghai as a classical case to explore the spatial evolution process, features, and influencing factors of the e-sports industry using the spatial analysis methods, including the kernel density estimation, nearest neighbor index, and the Kriging spatial interpolation analysis based on the data mining of Shanghai e-sports enterprises from 2006 to 2018. The results show that, first, according to factors such as historical background, policy support, and development characteristics, the e-sports industry in Shanghai can be divided into the initial stage from 2006 to 2010, the rapid development stage from 2010 to 2014, and the explosive growth stage from 2014 to 2018. Second, the spatial distribution of the e-sports industry in Shanghai has evolved from a dual-core aggregation to a multi-core aggregation with the characteristics of central aggregation and simultaneous outward expansion. The south and north are the main directions of the expansion of e-sports enterprises. Third, high-capital e-sports enterprises tend to focus on software parks and universities in the surrounding area. There are currently four high-capital hotspots, namely, Zizhu Science Park in Minhang District, Zhaojiabang Road in Xuhui District, Lantian Enterprise Development Industrial Park in Jiading District, and Tiandi Software parks in Putuo District. These hotspots will have more opportunities to extend more competitive e-sports enterprises in the future because spin-off firms can inherit excellent capabilities from the parent firms. Fourth, based on the analysis framework of agglomeration economy—enterprise spin-off—institutional environment, this study analyzes the evolution mechanism of e-sports industry cluster in Shanghai. The agglomeration economy plays a centripetal role, the enterprise spin-off enables new enterprises to inherit successful routines from the parent company, and the institutional environment is conducive to the formation and management of industries. Compared with previous studies which showed that the government plays a smaller role in promoting the cultural industry, the development of the e-sports industry is affected more by the institutional environment. Finally, at an urban scale, government policy planning has a guiding effect on the location selection of the e-sports industry. High-quality human resources, economic development level, e-sports market environment, and transportation convenience are the key factors for the aggregation of e-sports enterprises. In addition, compared with traditional industries, the e-sports industry has the characteristics of competition as a sporting activity. Furthermore, the excitement of competition and the holding of big e-sports events will have a significant impact on the development of the e-sports industry. This study explores the spatial-temporal pattern, evolution process, influencing factors, and evolution mechanisms of the e-sports industry in Shanghai from the perspective of evolutionary economic geography. This study verifies and enriches the theory of evolutionary economic geography from an empirical perspective, providing a theoretical basis for optimizing the spatial distribution of the e-sports industry, developing an e-sports industry cluster district, and enhancing the urban cultural brand. It also provides a decision-making reference for other cities to develop the e-sports industry.