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Corrosion of electrocatalysts during electrochemical operations, such as low potential - high potential cyclic swapping, can cause significant performance degradation. However, the electrochemical corrosion dynamics, including structural changes, especially site and composition specific ones, and their correlation with electrochemical processes are hidden due to the insufficient spatial-temporal resolution characterization methods. Using electrochemical liquid cell transmission electron microscopy, we visualize the electrochemical corrosion of Pd@Pt core-shell octahedral nanoparticles towards a Pt nanoframe. The potential-dependent surface reconstruction during multiple continuous in-situ cyclic voltammetry with clear redox peaks is captured, revealing an etching and deposition process of Pd that results in internal Pd atoms being relocated to external surface, followed by subsequent preferential corrosion of Pt (111) terraces rather than the edges or corners, simultaneously capturing the structure evolution also allows to attribute the site-specific Pt and Pd atomic dynamics to individual oxidation and reduction events. This work provides profound insights into the surface reconstruction of nanoparticles during complex electrochemical processes.

Interferons play a major role in innate immunity and disease resistance. Porcine interferon alpha has 17 subtypes, and their gene sequences, tissue expression profiles, and antiviral activities have been primarily studied in domestic pigs but not in minipigs. Bama minipigs are genetically stable disease-resistant and making them as laboratory animal models for bioscience studies. To define the potential mechanism for disease resistance, in this study, we cloned 17 subtypes of Porcine interferon alpha genes in Bama minipigs using high fidelity polymerase chain reaction and subsequent sequencing. Sequence alignment showed that the 17 porcine interferon alpha subtypes were 98%–100 % homologous in those of domestic pigs. However, significantly different tissue expression profiles of PoIFN-α subtypes were found in the two pig species using real-time quantitative RT-PCR. Among the 10 different Bama minipig tissues tested, significant expression of multi-subtype porcine interferon alpha was detected in the lymph nodes and spleen, whereas no or low expression of fewer subtypes was detected in the heart, lung, brain, and small intestine. Sequence analysis revealed that the porcine interferon alpha promoters were almost similar between the two pig species. A cytopathic effect inhibition assay showed that the recombinant 17 porcine interferon alpha subtypes purified from mammalian cells had significantly different antiviral profile against vesicular stomatitis virus, porcine pseudorabies virus and porcine reproductive and respiratory syndrome virus compared with those in domestic pigs. Our findings provide evidence that porcine interferon alpha subtypes are highly conserved between Bama minipigs and domestic pigs but show varied tissue expression pattern and antiviral capabilities, which may contribute to their differences in disease resistance.

Rapid progresses concerning wearable electronics call for stretchable batteries. Owing to the merits of high energy density and wide operating voltage range, organic electrolyte‐based lithium‐ion batteries (LIBs) take a large proportion in the powering markets. Due to the high sensitivity to moisture and oxygen, it is difficult to obtain long‐term reliable stretchable organic electrolyte‐based LIBs when they are directly exposed to the air. Benefiting from the outstanding gas impermeability of liquid metal (LM) and relatively good barrier properties for reactive acid gas molecules by polyisobutylene (PIB), an LM‐PIB seal is demonstrated for organic electrolyte‐based LIBs. In the seal, LM can prevent the inward permeation of oxygen and water vapor, and PIB can block the outward permeation of hydrolysis acid generated from the side reactions during the operation of the organic electrolyte‐based LIBs, which helps prevent the detrimental interaction between the hydrolysis acid and LM. A specific capacity of over 120 mAh g−1 is achieved and the battery shows consistent electrochemical performances under multiple deformations. This study offers a different design approach for long‐term operation of stretchable organic electrolyte‐based LIBs. [ABSTRACT FROM AUTHOR]

As a highly efficient and eco-friendly heat generation approach, the photothermal conversion process has been applied to many important areas such as desalination and medical treatments. We explored in this work the application of the photothermal conversion process for the fabrication of complex polymorphic calcium carbonate (CaCO3) structures. Through stepwise temperature modulation enabled by photothermal conversion, architectures of aragonite@calcite, calcite@aragonite, and calcite@aragonite@calcite that are composed of multiple polymorphic phases were obtained. The different polymorphic phases on the same architectures are confirmed by confocal Raman micro-spectroscopy analysis. Further modification of the substrates with a patterned self-assembled monolayer through soft lithography enabled the growth of arrays of the complex polymorphic CaCO3 structures on the surface. This study provides an efficient and promising methodology for thermally controlling the growth of materials with desired multi-phases and multi-functionalities for different applications. [ABSTRACT FROM AUTHOR]

Designing new materials and structure to sustain the corrosion during operation requires better understanding on the corrosion dynamics. Observation on how the corrosion proceeds in atomic scale is thus critical. Here, using a liquid cell, we studied the real-time corrosion process of palladium@platinum (Pd@Pt) core-shell nanocubes via transmission electron microscopy (TEM). The results revealed that multiple etching pathways operatively contribute to the morphology evolution during corrosion, including galvanic etching on non-defected sites with slow kinetics and halogen-induced etching at defected sites at faster rates. Corners are the preferential corrosion sites; both etching pathways are mutually restricted during corrosion. Those insights on the interaction of nanostructures with reactive liquid environments can help better engineer the surface structure to improve the stability of electrocatalysts as well as design a new porous structure that may provide more active sites for catalysis.

GPS has a sharp performance decline in terms of accuracy indoors due to the complex building structure. A combined algorithm, targeting at received signal strength indication (RSSI) calibration optimisation, depending on deep neural network training via input vector Γ and the target output vector Ψ, termed reference signal optimisation algorithm (RSOA) is proposed to improve the positioning accuracy in the indoor Bluetooth positioning networks. Experimental results show that the relative error of the proposed RSOA between the estimated results and the measured ones can reach as low as 0.2%, and the absolute errors can be reduced to 0.13 m at most within 10 m.

High diversity and differential evolution profiles have been observed for DD34E/ Tc1 transposons; several families originating from these groups, such as DD34E/ ZB , DD34E/ SB , DD35E/ TR , DD36E/ IC, and DD38E/ IT , have been well defined. Even though Frisky , Tiang , Tsessebe, and Topi transposons have been identified in Anopheles gambiae , their taxonomic distribution and phylogenetic relationship in nature remain largely unknown. The evolutionary profiles of Frisky , Tiang , Tsessebe , and Topi homology transposons were investigated in the current study. In total, 254 homology transposons of Frisky , Tiang , Hob , Tsessebe, and Topi were obtained in 200 species by data mining. The phylogenetic tree revealed that these transposons were classified into five main clades (Frisky , Tiang , Hob , Tsessebe , and Topi) forming a monophyletic clade with 98% bootstrap support, belonging to the DD34E/ Tc1 group, and named as Skipper (SK). SK transposons show a wide distribution in animals; however, differential taxonomic distribution patterns were observed for the subfamilies of Frisky , Tiang , Hob , Tsessebe, and Topi ; extensive invasion of Frisky in animals was found, whereas Tiang , Hob , Tsessebe, and Topi were mainly detected in Diptera. SK elements share a similar structural organization and display high sequence identities across subfamilies. Evolutionary dynamics and structural analysis revealed that SK s in some species, such as Bombyx mori , Lordiphosa magnipectinata , Carassius gibelio , Triplophysa dalaica , and Silurus glanis , have recently evolved and present as intact copies, indicating that SK s in these genomes may be active. Together, these observations improve our understanding of the diversity of DD34E/ Tc1 transposons and their impacts on genome evolution in animals. [ABSTRACT FROM AUTHOR]

Here, we comprehensively analysed the abundance, diversity, and activity of Tc1/mariner transposons in African coelacanth (Latimeria chalumnae). Fifteen Tc1/mariner autonomous transposons were identified and grouped into six clades: DD34E/Tc1, DD34D/mariner, DD35D/Fot, DD31D/pogo, DD30-31D/pogo-like, and DD32-36D/Tigger, belonging to three known families: DD34E/Tc1, DD34D/mariner, and DD*D/pogo (DD35D/Fot, DD31D/pogo, DD30-31D/pogo-like, and DD32-36D/Tigger). Thirty-one miniature inverted-repeat transposable element (MITE) transposons of Tc1/mariner were also identified, and 20 of them display similarity to the identified autonomous transposons. The structural organization of these full Tc1/mariner elements includes a transposase gene flanked by terminal inverted repeats (TIRs) with TA dinucleotides. The transposases contain N-terminal DNA binding domain and a C-terminal catalytic domain characterized by the presence of a conservative D(Asp)DE(Glu)/D triad that is essential for transposase activity. The Tc1/mariner superfamily in coelacanth exhibited very low genome coverage (0.3%), but it experienced an extraordinary difference of proliferation dynamics among the six clades identified; moreover, most of them exhibited a very recent and current proliferation, suggesting that some copies of these transposons are putatively active. Additionally, at least four functional genes derived from Tc1/mariner transposons were found. We provide an up-to-date overview of Tc1/mariner in coelacanth, which may be helpful in determining genome and gene evolution in this living fossil. Key words: Latimeria chalumnae, Tc1/mariner, transposons, evolution, domestication. Dans ce travail, les auteurs analysent de maniere exhaustive l'abondance, la diversite et l'activite des transposons de la famille Tc1/mariner chez le coelacanthe africain (Latimeria chalumnae). Quinze transposons Tc1/mariner autonomes ont ete identifies et groupes en six clades : DD34E/Tc1, DD34D/mariner, DD35D/Fot, DD31D/pogo, DD30-31/type pogo et DD32-36/Tigger, lesquels appartiennent a trois familles connues : DD34E/Tc1, DD34D/mariner et DDxD/pogo (DD35D/Fot, DD31D/pogo, DD30-31/type pogo et DD32-36/Tigger). Trente et un transoposons MITE ('Miniature Inverted Terminal Element') derives de Tc1/mariner ont egalement ete identifies, et vingt d'entre eux presentaient une similarite avec les transposons autonomes identifies. Ces elements Tc1/mariner complets presentaient une organisation incluant un gene codant pour la transposase flanque des repetitions terminales inversees (TIR) avec des dinucleotides TA. Les transposases contiennent un domaine de liaison a l'ADN en N-terminal et un domaine catalytique en C-terminal, lequel est caracterise par la presence d'un trio d'acides amines D(Asp)DE-(Glu)/D qui est essentiel pour l'activite transposase. La superfamille Tc1/mariner chez le coelacanthe compte pour une tres faible part du genome (0,3 %), mais presente une extraordinaire difference dans la dynamique de proliferation parmi les six clades identifies. De plus, la plupart d'entre eux affichent une proliferation tres recente et toujours en cours, ce qui suggere que certaines copies de ces transposons sont potentiellement actives. Aussi, au moins quatre genes fonctionnels derives de transposons Tc1/mariner ont ete trouves. Les auteurs contribuent ici une vue globale a jour des elements Tc1/mariner chez le coelacanthe, laquelle sera possiblement utile pour determiner l'evolution du genome et des genes au sein de ce fossile vivant. [Traduit par la Redaction] Mots-cles : Latimeria chalumnae, Tc1/mariner, transposons, evolution, domestication., Introduction Transposable elements (TEs) are widely distributed in the genome of most organisms. During the processes of biological evolution, TEs have dramatically affected the size and structure of the genomes [...]