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The On-Load Tap Changer (OLTC) is the only movable mechanical component in a converter transformer. To ensure the reliable operation of the OLTC and to promptly detect mechanical faults in OLTCs to prevent them from developing into electrical faults, this paper proposes a fault diagnosis method for OLTCs based on a combination of Particle Swarm Optimization (PSO) algorithm and Least Squares Support Vector Machine (LSSVM) with multi-feature fusion. Firstly, a multi-feature extraction method based on time/frequency domain statistics, synchrosqueezed wavelet transform, singular value decomposition, and multi-scale modal decomposition is proposed. Meanwhile, the random forest algorithm is used to screen features to eliminate the influence of redundant features on the accuracy of fault diagnosis. Secondly, the PSO algorithm is introduced to optimize the hyperparameters of LSSVM to obtain optimal parameters, thereby constructing an optimal LSSVM fault diagnosis model. Finally, different types of feature combinations are utilized for fault diagnosis, and the impact of these feature combinations on the fault diagnosis results is compared. Experimental results indicate that features of different types can complement each other, making the OLTC state information carried by multi-dimensional features more comprehensive, which helps to improve the accuracy of fault diagnosis. Compared with four traditional fault diagnosis methods, the proposed method performs better in fault diagnosis accuracy, achieving the highest accuracy of 98.58%, which can help to detect mechanical faults in the OLTC early and reduce the system's downtime. [ABSTRACT FROM AUTHOR]

Owing to the abundant reserves and low cost, sodium‐ion batteries (SIBs) have garnered unprecedented attention. However, their widespread adoption is hindered by the scarcity of alternative anodes with fast‐charging capability and high stability. To overcome this challenge, a fast‐charging SIB anode, N‐doped Bi/BiOCl embedded in a carbon framework (Bi/BiOCl@NC) with a fast Na+ transport channel and ultra‐high structural stability, is developed. During cycling in ether electrolyte, Bi/BiOCl@NC undergoes a remarkable transformation into a 3D porous skeleton, which significantly reduces the Na+ transport pathway and accommodates volume changes. By employing density functional theory calculations to simulate the storage behavior of Na+ in the structure, Bi/BiOCl@NC is theoretically characterized to have a low Na+ transport barrier (0.056 eV) and outstanding electronic conductivity. Such unique characteristics induce Bi/BiOCl@NC anode to have an ultra‐high Na+ storage capacity of 410 mAh·g−1 at 20 A·g−1 and exhibit outstanding cycling stability with over 2300 cycles at 10 A·g−1. This study provides a rational scenario for the fast‐charging anode design and will enlighten more advanced research to promote the exploitation of SIBs. [ABSTRACT FROM AUTHOR]

All pathogens must acquire nutrients from their hosts. The intracellular bacterial pathogen Legionella pneumophila, the etiological agent of Legionnaires' disease, requires host amino acids for growth within cells. The mechanistic target of rapamycin complex 1 (mTORC1) is an evolutionarily conserved master regulator of host amino acid metabolism. Here, we identify two families of translocated L. pneumophila effector proteins that exhibit opposing effects on mTORC1 activity. The Legionella glucosyltransferase (Lgt) effector family activates mTORC1, through inhibition of host translation, whereas the SidE/SdeABC (SidE) effector family acts as mTORC1 inhibitors. We demonstrate that a common activity of both effector families is to inhibit host translation. We propose that the Lgt and SidE families of effectors work in concert to liberate host amino acids for consumption by L. pneumophila.

There has been a long-standing challenge in developing locally stationary Gaussian process models concerning how to obtain flexible partitions and make predictions near boundaries. In this work, we develop a new class of locally stationary stochastic processes, where local partitions are modeled by a soft partition process via predictive random spanning trees that leads to highly flexible spatially contiguous subregion shapes. This valid nonstationary process model knits together local models such that both parameter estimation and prediction can be performed under a unified and coherent framework, and it captures both discontinuities/abrupt changes and local smoothness in a spatial random field. We propose a theoretical framework to study the Bayesian posterior concentration concerning the behavior of this Bayesian nonstationary process model. The performance of the proposed model is illustrated with simulation studies and real data analysis of precipitation rates over the contiguous United States. for this article are available online. [ABSTRACT FROM AUTHOR]

Many bacterial pathogens have evolved effective strategies to interfere with the ubiquitination network to evade clearance by the innate immune system. Here, we report that OTUB1, one of the most abundant deubiquitinases (DUBs) in mammalian cells, is subjected to both canonical and noncanonical ubiquitination during Legionella pneumophila infection. The effectors SidC and SdcA catalyze OTUB1 ubiquitination at multiple lysine residues, resulting in its association with a Legionella-containing vacuole. Lysine ubiquitination by SidC and SdcA promotes interactions between OTUB1 and DEPTOR, an inhibitor of the MTORC1 pathway, thus suppressing MTORC1 signaling. The inhibition of MTORC1 leads to suppression of host protein synthesis and promotion of host macroautophagy/autophagy during L. pneumophila infection. In addition, members of the SidE family effectors (SidEs) induce phosphoribosyl (PR)-linked ubiquitination of OTUB1 at Ser16 and Ser18 and block its DUB activity. The levels of the lysine and serine ubiquitination of OTUB1 are further regulated by effectors that function to antagonize the activities of SidC, SdcA and SidEs, including Lem27, DupA, DupB, SidJ and SdjA. Our study reveals an effectors-mediated complicated mechanism in regulating the activity of a host DUB. Abbreviations: BafA1: bafilomycin A1; BMDMs: bone marrow-derived macrophages; DUB: deubiquitinase; Dot/Icm: defective for organelle trafficking/intracellular multiplication; DEPTOR: DEP domain containing MTOR interacting protein; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; L. pneumophila: Legionella pneumophila; LCV: Legionella-containing vacuole; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MOI: multiplicity of infection; MTORC1: mechanistic target of rapamycin kinase complex 1; OTUB1: OTU deubiquitinase, ubiquitin aldehyde binding 1; PR-Ub: phosphoribosyl (PR)-linked ubiquitin; PTM: posttranslational modification; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SidEs: SidE family effectors; Ub: ubiquitin. [ABSTRACT FROM AUTHOR]

The Yamansu iron deposit, hosted in submarine volcanic rocks, is located in the Aqishan--Yamansu Fe--Cu metallogenic belt of eastern Tianshan, Xinjiang. New pyrite Re--Os and pyroxene diorite intrusion ages and the chemistry of magnetite constrain the origin of the deposit. The Yamansu orebodies display banded or lenticular forms and sharp contacts with marble and garnet skarn. Pyrite associated with magnetite from hydrothermal massive ores has a Re--Os isochron age of 320.3 [+ or -] 9.1 Ma, which is consistent with the Carboniferous age of volcanic rocks. However, the pyroxene diorite age (252.1 [+ or -] 3.7 Ma) is obviously younger than the mineralization age, implying no temporal relationship between mineralization and intrusion. Magnetite samples from different ores in the Yamansu deposit are suggested to have a magmatic--hydrothermal origin. The magmatic primary magnetite is rich in Ti[O.sub.2] and poor in Si[O.sub.2], MgO, and CaO, similar to magnetite from Kiruna type deposits. The hydrothermal magnetite is rich in FeO, CaO, and Si[O.sub.2] but poor in Ti[O.sub.2] and shows oscillatory zoning. Moreover, magmatic and hydrothermal magnetite samples show different characteristic normalized rare earth element and trace element patterns. A combination of ore fabrics, discrimination diagrams, and normalized patterns for magnetite samples can reflect the magmatic--hydrothermal process. The Yamansu iron deposit is spatially and temporally associated with Carboniferous volcanism, and we propose that the magmatic magnetite ores were derived from iron-rich melt through melt immiscibility. The residual iron-rich magma ascended and erupted along with hydrothermal activity; then moderate to large amounts of hydrothermal massive, banded, or disseminated magnetite formed with skarns. Key words: magnetite, mineral geochemistry, Re--Os geochronology, Yamansu iron deposit, eastern Tianshan, Xinjiang. Le gisement de fer de Yamansu, contenu dans des roches volcaniques sous-marines, est situé dans la ceinture métallifère à Fe--Cu d'Aqishan--Yamansu du Tianshan oriental (Xinjiang, Chine). De nouveaux âges Re--Os sur pyrite et d'intrusions de diorite à pyroxène, ainsi que la chimie de la magnétite permettent de mieux circonscrire l'origine du gisement. Les corps minéralisés de Yamansu présentent des formes rubanées et lenticulaires et des contacts nets avec des marbres et des skarns à grenat. De la pyrite associée à de la magnétite dans des minerais hydrothermaux massifs donne un âge d'isochrone de Re--Os de 320,3 [+ ou -] 9,1 Ma, qui concorde avec l'âge carbonifère des roches volcaniques. Cependant, l'âge de la diorite à pyroxène (252,1 [+ ou -] 3,7 Ma) est clairement plus jeune que celui de la minéralisation, ce qui indique que la minéralisation et l'intrusion ne sont pas reliées dans le temps. Il est suggéré que l'origine d'échantillons de magnétite provenant de différents minerais dans le gisement de Yamansu serait magmatique-hydrothermale. La magnétite magmatique primaire est riche en Ti[O.sub.2] et pauvre en Si[O.sub.2], MgO et CaO, à l'instar de la magnétite de gisements de type Kiruna. La magnétite hydrothermale est riche en FeO, CaO et Si[O.sub.2], mais pauvre en Ti[O.sub.2] et présente une zonation oscillatoire. Des échantillons de magnétite magmatique et hydrothermale présentent en outre différents spectres des terres rares normalisés et d'éléments en traces caractéristiques. Une combinaison de fabriques du minerai, de diagrammes de discrimination et de spectres normalisés pour des échantillons de magnétite pourrait refléter le processus magmatique-hydrothermal. Le gisement de fer de Yamansu est associé dans l'espace et le temps à un volcanisme carbonifère, et nous proposons que les minerais de magnétite magmatique sont dérivés d'un magma riche en fer produit par l'immiscibilité de magmas préexistants. Le magma résiduel richeen fer est monté et a été mis en place, accompagné d'activité hydrothermale; ensuite, des quantités modérées à grandes de magnétite massive, rubanée ou disséminée se sont formées avec des skarns. [Traduit par la Rédaction] Mots-clés : magnétique, géochimie des minéraux, géochronologie Re--Os, gisement de fer de Yamansu, Tianshan oriental, Xinjiang., Introduction Volcanic-rock-hosted iron deposits are one of the most important types of Fe-rich deposits (Cliff et al. 1990; Nystrom and Henriquez 1994; Jonsson et al. 2013; Chai et al. 2014), [...]