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If a light axion is present during inflation and becomes part of dark matter afterwards, its quantum fluctuations contribute to dark matter isocurvature. In this article, we introduce a whole new suite of cosmological observables for axion isocurvature, which could help test the presence of axions, as well as its coupling to the inflaton and other heavy spectator fields during inflation such as the radial mode of the Peccei-Quinn field. They include correlated clock signals in the curvature and isocurvature spectra, and mixed cosmological-collider non-Gaussianities involving both curvature and isocurvature fluctuations with shapes and running unconstrained by the current data analyses. Taking into account of the existing strong constraints on axion isocurvature fluctuations from the CMB, these novel signals could still be sizable and potentially observable. In some models, the signals, if observed, could even help us significantly narrow down the range of the inflationary Hubble scale, a crucial parameter difficult to be determined in general, independent of the tensor mode. [ABSTRACT FROM AUTHOR]

Industrial wastewater containing large amounts of organic pollutants is a severe threat to the environment and human health. Thus, the rapid detection and removal of these pollutants from wastewater are essential to protect public health and the ecological environment. In this study, a multifunctional and reusable surface-enhanced Raman scattering (SERS) substrate by growing Ag nanoparticles (NPs) on ZnO nanorods (NRs) was produced for detecting and degrading Rhodamine B (RhB) dye. The ZnO/Ag substrate exhibited excellent sensitivity, and the limit of detection (LOD) for RhB was as low as 10−11 M. Furthermore, the SERS substrate could efficiently degrade RhB, with a degradation efficiency of nearly 100% within 150 min. Moreover, it retained good SERS activity after multiple repeated uses. The interaction between Ag NPs, ZnO, and RhB was further investigated, and the mechanism of SERS and photocatalysis was proposed. The as-prepared ZnO/Ag composite structure could be highly applicable as a multifunctional SERS substrate for the rapid detection and photocatalytic degradation of trace amounts of organic pollutants in water. [ABSTRACT FROM AUTHOR]

• Proposing the DC cable axial temperature field as an evaluation condition for DC cable operation. • A high-fidelity digital twin model is built for the DC cable. • Investigating the impact of fast and accurate computation with Sequence-to-Sequence residual neural networks is crucial for the prediction and maintenance of digital twin models. • Accuracy can be guaranteed while achieving millisecond-level calculations. The most important features of digital twin technology for transmission and transformation equipment are symbiotic evolution and state prediction. In constructing the digital twin model for DC cables, the transient and steady-state temperature fields need to be considered comprehensively in the modeling process to consider the multi-physical field coupling, mathematical model, operational data, and environmental conditions in specific cases, which makes it difficult to satisfy the real-time requirements of the digital twin. To solve this problem, in this paper, a digital twin technology architecture for DC cables is proposed, and a neural network learning model is constructed to minimize the latency due to the complexity of the model simulation. Moreover, an efficient digital twin model that is based on the model-driven approach is developed for the fast computation of the axial temperature field of DC cables. The use of the Sequence-to-Sequence residual neural network algorithm for the reduced-order multi-physics field coupling modeling reduces the computational time and ensures as much accuracy as possible up to the finite element model simulation. The simulation results show that the use of the digital twin model reduces the simulation time from 275 s to 0.56 s, and the relative error between the accuracy of the digital twin model and the finite element model for the axial temperature field of the DC cable is 0.46 %. Finally, verification of the reasonableness and feasibility of the proposed method is carried out via an experimental platform according to the standard of CIGRE TB496. In particular, the maximum value of the DC cable temperature is verified to have a small error compared with the result of the Sequence-to-Sequence calculation under specific working conditions. [ABSTRACT FROM AUTHOR]

We propose an inflationary primordial feature model that can explain both the large and small-scale anomalies in the currently measured cosmic microwave background anisotropy spectra, revealing a clip of adventurous history of the Universe during its primordial epoch. Although the model is currently statistically indistinguishable from the Standard Model, we show that planned observations such as the Simons Observatory, LiteBIRD and CMB-S4 will complement each other in distinguishing the model differences due to their accurate E-mode polarization measurements, offering very optimistic prospects for a detection or exclusion. The model predicts a signal of classical primordial standard clock, which can also be used to distinguish the inflation and alternative scenarios in a model-independent fashion. [ABSTRACT FROM AUTHOR]

Technology may bring seismic changes to media, and China is no exception. In this article, we examine factors affecting the adoption of media technology in China, including government policies, historical contexts, and other social contributors. We also provide an analysis of changes brought about by technology, in the industry and in academic research. Our goal is to delineate a clear picture of how technology interacts with society and to provide background knowledge and contextual information for this JoBEM special issue focusing on Chinese electronic media. [ABSTRACT FROM AUTHOR]

Accurate monitoring of insulation aging of oil-paper insulation power equipment such as oil-immersed transformers is a key and difficult point in the field of high voltage research. In this paper, a method based on Raman spectroscopy to diagnose the aging degree of oil-paper insulation is discussed. Raman detections of the samples were carried out on a self-built Raman detection platform. The partial least squares method was used to extract and analyze the spectral features. The aging time of the sample was used to supervise the feature extraction of oil-paper insulation Raman data, and the intrinsic mathematical relationship between the Raman features of oil-paper insulation and the aging was excavated. Finally, a quantitative aging diagnostic model based on Raman spectral features of oil-paper insulation to predict its aging state was built with the assistance of the support vector regression method. The results of aging time prediction for 30 test samples show that the mean square error is 0.0123 and the square of correlation coefficient is 0.987. The proposed method provides a new idea for Raman aging diagnosis of oil-paper insulation. [ABSTRACT FROM AUTHOR]

We work out the Standard Model (SM) mass spectrum during inflation with quantum corrections, and explore its observable consequences in the squeezed limit of non-Gaussianity. Both non-Higgs and Higgs inflation models are studied in detail. We also illustrate how some inflationary loop diagrams can be computed neatly by Wick-rotating the inflation background to Euclidean signature and by dimensional regularization. [ABSTRACT FROM AUTHOR]

Inflation models are numerous. It is extremely difficult, if possible at all, to identify the actual underlying inflation model of our primordial universe. Thus, for the purpose of proving/falsifying inflation and using inflation to probe new physics, model-independent approaches are crucial. Massive fields play a uniquely important role in those missions. This short review is based on a talk by one of the authors (YW) in the 2nd LeCosPA Symposium. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method combining derivatization reaction and SERS is used to determine methanol in transformer oil. • Ag nanoparticles are deposited on ZnO nanoflowers as an efficient SERS substrate. • Methanol without obvious Raman signal can be converted to SERS-sensitive compounds by derivatization reaction. • The proposed method exhibits high sensitivity and selectivity for detecting trace methanol. Methanol dissolved in transformer oil is used as an aging marker for the degradation of oil-paper insulation systems. Rapid and precise methanol testing is critical for determining the aging status of oil-paper insulation systems. In this study, a new method was proposed for the combination of a derivative reaction and SERS to detect dissolved methanol in transformer oil. Methanol reacted with 4-amino-5-hydrazino-3-mercapto-1,2,4-triazole (AHMT) after it was oxidized in acidic potassium permanganate, this converted methanol with no visible SERS signal into SERS-sensitive compounds. Then, a three-dimensional (3D) structure of flower-like ZnO modified with Ag nanoparticles (Ag NPs) was constructed as a SERS substrate to collect spectra. At the characteristic peak of 825 cm−1, there was a good linear relationship between the concentration and peak area over the range of 1–10000 μg/L, and the limit of detection (LOD) was as low as 0.87 μg/L. The method is simple, fast, sensitive, and has outstanding anti-interference properties; it is suitable for detecting trace methanol and has broad application prospects in the field of aging diagnosis of oil-paper insulation systems in transformer. [ABSTRACT FROM AUTHOR]

The voltage endurance coefficient n of cross‐linked polyethylene (XLPE) insulation is an important indicator for the analysis of insulation failure mechanism. Accurately obtaining the value of n can provide technical support for the reliability evaluation of cable operation. The constant stress method and the step stress method are used to obtain the values of n, but the test parameters can influence the accuracy of the obtained n values. Two methods for selecting test parameters are proposed. The equivalence between the two methods is established, providing theoretical support for the accurate evaluation of the n value of solid insulation materials by using the step stress method. The accuracy of the evaluation results is verified by analyzing the test data. The test results show that the nstep = 13.04 evaluated by the step stress test with the proposed parameter selection method is consistent with the test result of constant stress nconstant = 12.83. [ABSTRACT FROM AUTHOR]

Standard Clocks in the primordial epoch leave a special type of features in the primordial perturbations, which can be used to directly measure the scale factor of the primordial universe as a function of time a ( t ) , thus discriminating between inflation and alternatives. We have started to search for such signals in the Planck 2013 data using the key predictions of the Standard Clock. In this Letter, we summarize the key predictions of the Standard Clock and present an interesting candidate example in Planck 2013 data. Motivated by this candidate, we construct and compute full Standard Clock models and use the more complete prediction to make more extensive comparison with data. Although this candidate is not yet statistically significant, we use it to illustrate how Standard Clocks appear in Cosmic Microwave Background (CMB) and how they can be further tested by future data. We also use it to motivate more detailed theoretical model building. [ABSTRACT FROM AUTHOR]

Abstract: Experimentally distinguishing different primordial universe paradigms that lead to the Big Bang model is an outstanding challenge in modern cosmology and astrophysics. We show that a generic type of signals that exist in primordial universe models can be used for such purpose. These signals are induced by tiny oscillations of massive fields and manifest as features in primordial density perturbations. They are capable of recording the time-dependence of the scale factor of the primordial universe, and therefore provide direct evidence for specific paradigm. These signals present special opportunities and challenges for experiments and data analyses. [Copyright &y& Elsevier]

Abstract: We discuss the Montonen–Olive electric–magnetic duality for the BPS massless monopole clouds in supersymmetric Yang–Mills theory with non-Abelian unbroken gauge symmetries. We argue that these low energy non-Abelian clouds can be identified as the duals of the infrared bremsstrahlung radiation of the non-Abelian massless particles. After we break the supersymmetry to by adding a superpotential, or to by further adding soft breaking terms, these non-Abelian clouds will generally condense and screen the non-Abelian charges of the massive monopole probes. The effective mass of these dual non-Abelian states is likely to persist as we lower the energy to the QCD scale, if all the non-Abelian Higgs particles are massive. This can be regarded as a manifestation of the non-Abelian dual Meissner effect above the QCD scale, and we expect it to continuously connect with the confinement as we lower the supersymmetry breaking scale to the QCD scale. [Copyright &y& Elsevier]

The digital information age has ushered in a new set of rules for media and media users to transform society overtime. This special issue on Chinese electronic media presents an interesting case of that transformation, by contextualizing the interactions between media content, processes, and consumption as well as identifying variables of social constrains in Chinese society. While some of the topics studied are more uniquely Chinese, other topics examined are broadly generalizable to a global setting. Our goal is to foster additional scholarly research to further advance our theoretical under- standing of these socially important topics in the future. [ABSTRACT FROM AUTHOR]

Background: The main challenge in personalized treatment of breast cancer (BC) is how to integrate massive amounts of computing resources and data. This study aimed to identify a novel molecular target that might be effective for BC prognosis and for targeted therapy by using network-based multidisciplinary approaches. Methods: Differentially expressed genes (DEGs) were first identified based on ESTIMATE analysis. A risk model in the TCGA-BRCA cohort was constructed using the risk score of six DEGs and validated in external and clinical in-house cohorts. Subsequently, independent prognostic factors in the internal and external cohorts were evaluated. Cell viability CCK-8 and wound healing assays were performed after PTGES3 siRNA was transiently transfected into the BC cell lines. Drug prediction and molecular docking between PTGES3 and drugs were further analyzed. Cell viability and PTGES3 expression in two BC cell lines after drug treatment were also investigated. Results: A novel six-gene signature (including APOOL, BNIP3, F2RL2, HINT3, PTGES3 and RTN3) was used to establish a prognostic risk stratification model. The risk score was an independent prognostic factor that was more accurate than clinicopathological risk factors alone in predicting overall survival (OS) in BC patients. A high risk score favored tumor stage/grade but not OS. PTGES3 had the highest hazard ratio among the six genes in the signature, and its mRNA and protein levels significantly increased in BC cell lines. PTGES3 knockdown significantly inhibited BC cell proliferation and migration. Three drugs (gedunin, genistein and diethylstilbestrol) were confirmed to target PTGES3, and genistein and diethylstilbestrol demonstrated stronger binding affinities than did gedunin. Genistein and diethylstilbestrol significantly inhibited BC cell proliferation and reduced the protein and mRNA levels of PTGES3. Conclusions: PTGES3 was found to be a novel drug target in a robust six-gene prognostic signature that may serve as a potential therapeutic strategy for BC. [ABSTRACT FROM AUTHOR]

The thrust from corona discharge might be a promising propulsion technology in future aviation due to its advantage of not requiring mechanical moving parts. Although the thrust from corona discharge has been researched by many scholars, the effect of the applied voltage's polarity on the thrust has received little attention. This polarity effect might be very important for some special electrohydrodynamic thrusters. This paper firstly built a test platform to reveal the effect of the applied voltage's polarity on both the thrust and the corona current from a pair of symmetrically distributed needle electrodes. Then the applied voltage's polarity on the electrical field distribution between a pair of needle-plate electrodes was simulated. Finally, the relationship between the space ions at the tip of the needle electrode and the thrust are discussed. The results show that a negative needle electrode with a smaller curvature radius has a stronger thrust than a positive one with a larger curvature radius, and a stronger thrust corresponds to a higher corona current. The local electric field is enhanced by the space ions at the tip of a negative needle electrode, while it is weakened by a positive needle electrode. This results in the polarity of thrust. [ABSTRACT FROM AUTHOR]

Summary: Amylose content is a crucial physicochemical property responsible for the eating and cooking quality of rice (Oryza sativa L.) grain and is mainly controlled by the Waxy (Wx) gene. Previous studies have identified several Dull genes that modulate the expression of the Wxb allele in japonica rice by affecting the splicing efficiency of the Wxb pre‐mRNA. Here, we uncover dual roles for a novel Dull gene in pre‐mRNA splicing and microRNA processing. We isolated the dull mutant, du13, with a dull endosperm and low amylose content. Map‐based cloning showed that Du13 encodes a C2H2 zinc‐finger protein. Du13 coordinates with the nuclear cap‐binding complex to regulate the splicing of Wxb transcripts in rice endosperm. Moreover, Du13 also regulates alternative splicing of other protein‐coding transcripts and affects the biogenesis of a subset of microRNAs. Our results reveal an evolutionarily conserved link between pre‐mRNA splicing and microRNA biogenesis in rice endosperm. Our findings also provide new insights into the functions of Dull genes in rice and expand our knowledge of microRNA biogenesis in monocots. [ABSTRACT FROM AUTHOR]

Key message: FLO15encodes a plastidic glyoxalase I protein, OsGLYI7, which affects compound starch granule formation and starch synthesis in rice endosperm.Abstract: Starch synthesis in rice (Oryza sativa) endosperm is a sophisticated process, and its underlying molecular machinery still remains to be elucidated. Here, we identified and characterized two allelic rice floury endosperm 15 (flo15) mutants, both with a white-core endosperm. The flo15 grains were characterized by defects in compound starch granule development, along with decreased starch content. Map-based cloning of the flo15 mutants identified mutations in OsGLYI7, which encodes a glyoxalase I (GLYI) involved in methylglyoxal (MG) detoxification. The mutations of FLO15/OsGLYI7 resulted in increased MG content in flo15 developing endosperms. FLO15/OsGLYI7 localizes to the plastids, and the in vitro GLYI activity derived from flo15 was significantly decreased relative to the wild type. Moreover, the expression of starch synthesis-related genes was obviously altered in the flo15 mutants. These findings suggest that FLO15 plays an important role in compound starch granule formation and starch synthesis in rice endosperm. [ABSTRACT FROM AUTHOR]

Pyruvate kinase (PK) is a key enzyme in glycolysis and carbon metabolism. Here, we isolated a rice (Oryza sativa) mutant, w59, with a white‐core floury endosperm. Map‐based cloning of w59 identified a mutation in OsPKpα1, which encodes a plastidic isoform of PK (PKp). OsPKpα1 localizes to the amyloplast stroma in the developing endosperm, and the mutation of OsPKpα1 in w59 decreases the plastidic PK activity, resulting in dramatic changes to the lipid biosynthesis in seeds. The w59 grains were also characterized by a marked decrease in starch content. Consistent with a decrease in number and size of the w59 amyloplasts, large empty spaces were observed in the central region of the w59 endosperm, at the early grain‐filling stage. Moreover, a phylogenetic analysis revealed four potential rice isoforms of OsPKp. We validated the in vitro PK activity of these OsPKps through reconstituting active PKp complexes derived from inactive individual OsPKps, revealing the heteromeric structure of rice PKps, which was further confirmed using a protein–protein interaction analysis. These findings suggest a functional connection between lipid and starch synthesis in rice endosperm amyloplasts. Pyruvate kinase (PK) functions in glycolysis. Mutation in plastidic OsPKpα1 resulted in dramatic changes to lipid and starch biosynthesis in rice endosperm. As plastidic PK plays a fundamental role in generating the precursors for fatty acid biosynthesis, our findings suggest a functional connection between lipid and starch synthesis in amyloplasts. [ABSTRACT FROM AUTHOR]

Abstract: A backcross inbred line population derived from a cross between Koshihikari and Kasalath was used to dissect the genetic relationship among chalkiness, protein content, and paste viscosity properties in rice in three environments. A total of 11 traits (or parameters) were analyzed, including percentage of grains with chalkiness (PGWC), protein content (PC) and protein index (PI), and eight parameters from the viscosity profile. PGWC, PC and PI were significantly correlated with the paste viscosity parameters. We identified 39 QTLs in three environments; ten QTL clusters emerged. Eight QTLs were consistently detected across the three environments and further confirmed using a set of chromosome segment substitution lines (CSSLs) where Kasalath was used as the donor parent and Koshihikari as the recurrent parent. One and two major clusters on chromosome 6 corresponded to the Wx and Alk loci, respectively. The former was responsible for PGWC and most of the viscosity parameters, and the latter for PI and some viscosity parameters. Particularly, QTL qPI-6.1 was linked with both the Wx and Alk loci. The co-locations of QTLs for PGWC and viscosity parameters and the linkage of qPI-6.1 and qBDV-6 at the Wx locus could be largely responsible for the phenotypic correlations between these traits. [Copyright &y& Elsevier]

Given its small chip area and high current density, the fault protection of SiC MOSFET is a serious challenge. In this paper, a gate voltage-based fault protection method for a SiC MOSFET subjected to short circuit type II also called fault under load is proposed. The circuit implementation of the proposed method is analyzed in detail. A test with a voltage of 200 V is conducted. Experimental results verify the effectiveness of the proposed method. It is exhibited the fault response time of the proposed method is less than 1 μs, which is very fast to protect a device and is conducive to the reliable and safe operation of SiC MOSFETs. [ABSTRACT FROM AUTHOR]