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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.

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]

The loss of ion cyclotron resonance frequencies (ICRF)-heated neutral beam injection ions in experimental advanced superconducting tokamak was numerically investigated by ORBIT code simulations. The effects of collisions and ripples on particle losses were taken into account, and the distributions of fast ions generated by different beams in combination with ICRF heating were calculated using the TRANSP code. Results showed that ICRF waves altered the orbital distributions of beam ions, causing an increase in trapped ions and fast ion losses. Additionally, for co-current injected beams, perpendicular injection resulted in higher fast ion losses in synergistic heating than tangential injection. The study also found that the synergistic effect of collisions and ripples enhanced fast ion losses, which were highly localized and generated a maximum heat load of 0.165 MW m−2 on the first wall. However, conducting synergy heating experiments at high plasma currents and low effective ion charge numbers can significantly reduce the loss of fast ions. [ABSTRACT FROM AUTHOR]

This report presents liquid metal-based infrared-modulating materials and systems with multiple modes to regulate the infrared reflection. Inspired by the brightness adjustment in chameleon skin, shape-morphing liquid metal droplets in silicone elastomer (Ecoflex) matrix are used to resemble the dispersed "melanophores". In the system, Ecoflex acts as hormone to drive the deformation of liquid metal droplets. Both total and specular reflectance-based infrared camouflage are achieved. Typically, the total and specular reflectances show change of ~44.8% and 61.2%, respectively, which are among the highest values reported for infrared camouflage. Programmable infrared encoding/decoding is explored by adjusting the concentration of liquid metal and applying areal strains. By introducing alloys with different melting points, temperature-dependent infrared painting/writing can be achieved. Furthermore, the multi-layered structure of infrared-modulating system is designed, where the liquid metal-based infrared modulating materials are integrated with an evaporated metallic film for enhanced performance of such system. Liquid metal-based infrared-modulating materials and systems have been developed to regulate the infrared reflection with multiple modes, which can be used for infrared camouflage, programmable infrared encryption, and infrared painting/writing. [ABSTRACT FROM AUTHOR]

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]

Simple Summary: Long terminal repeat retrotransposons (LTR-RTNs) are vital in genome evolution and diversity. The compact genomes of Tetraodontiformes provide an excellent model for studying LTR-RTN dynamics. An analysis of the genomes of ten tetraodontiform species revealed a total of 819 full-length LTR retrotransposon sequences classified into nine families spanning four distinct superfamilies. Among them, the Gypsy superfamily displayed the highest level of diversity. Takifugu stood out for having the highest abundance of LTR families and sequences. Evidence of recent LTR-RTN activity and multiple invasions was observed in specific tetraodontiform genomes. This investigation provides valuable insights into the evolution of LTR retrotransposons and their impact on the structure and evolution of compact tetraodontiform genomes. This study aimed to investigate the evolutionary profile (including diversity, activity, and abundance) of retrotransposons (RTNs) with long terminal repeats (LTRs) in ten species of Tetraodontiformes. These species, Arothron firmamentum, Lagocephalus sceleratus, Pao palembangensis, Takifugu bimaculatus, Takifugu flavidus, Takifugu ocellatus, Takifugu rubripes, Tetraodon nigroviridis, Mola mola, and Thamnaconus septentrionalis, are known for having the smallest genomes among vertebrates. Data mining revealed a high diversity and wide distribution of LTR retrotransposons (LTR-RTNs) in these compact vertebrate genomes, with varying abundances among species. A total of 819 full-length LTR-RTN sequences were identified across these genomes, categorized into nine families belonging to four different superfamilies: ERV (Orthoretrovirinae and Epsilon retrovirus), Copia, BEL-PAO, and Gypsy (Gmr, Mag, V-clade, CsRN1, and Barthez). The Gypsy superfamily exhibited the highest diversity. LTR family distribution varied among species, with Takifugu bimaculatus, Takifugu flavidus, Takifugu ocellatus, and Takifugu rubripes having the highest richness of LTR families and sequences. Additionally, evidence of recent invasions was observed in specific tetraodontiform genomes, suggesting potential transposition activity. This study provides insights into the evolution of LTR retrotransposons in Tetraodontiformes, enhancing our understanding of their impact on the structure and evolution of host genomes. [ABSTRACT FROM AUTHOR]

Transposable elements (TEs) mobility is capable of generating a large number of structural variants (SVs), which can have considerable potential as molecular markers for genetic analysis and molecular breeding in livestock. Our results showed that the pig genome contains mainly TE-SVs generated by short interspersed nuclear elements (51,873/76.49%), followed by long interspersed nuclear elements (11,131/16.41%), and more than 84% of the common TE-SVs (Minor allele frequency, MAF > 0.10) were validated to be polymorphic. Subsequently, we utilized the identified TE-SVs to gain insights into the population structure, resulting in clear differentiation among the three pig groups and facilitating the identification of relationships within Chinese local pig breeds. In addition, we investigated the frequencies of TEs in the gene coding regions of different pig groups and annotated the respective TE types, related genes, and functional pathways. Through genome-wide comparisons of Large White pigs and Chinese local pigs utilizing the Beijing Black pigs, we identified TE-mediated SVs associated with quantitative trait loci and observed that they were mainly involved in carcass traits and meat quality traits. Lastly, we present the first documented evidence of TE transduction in the pig genome. [ABSTRACT FROM AUTHOR]

Control of convection plays an important role in heat transfer regulation, bio/chemical sensing, phase separation, etc. Current convection controlling systems generally depend on engineered energy sources to drive and manipulate the convection, which brings additional energy consumption into the system. Here the use of human hand as a natural and sustainable infrared (IR) radiation source for the manipulation of liquid convection is demonstrated. The fluid can sense the change of the relative position or the shape of the hand with the formation of different convection patterns. Besides the generation of static complex patterns, dynamic manipulation of convections can also be realized via moving of hand or finger. The use of such sustainable convections to control the movement of a floating "boat" is further achieved. The use of human hands as the natural energy sources provides a promising approach for the manipulation of liquid convection without the need of extra external energy, which may be further utilized for low‐cost and intelligent bio/chemical sensing and separation. [ABSTRACT FROM AUTHOR]

The interest in endogenous retroviruses (ERVs) has been fueled by their impact on the evolution of the host genome. In this study, we used multiple pipelines to conduct a de novo exploration and annotation of ERVs in 13 species of the Caprinae subfamily. Through analyses of sequence identity, structural organization, and phylogeny, we defined 28 ERV groups within Caprinae, including 19 gamma retrovirus groups and 9 beta retrovirus groups. Notably, we identified four recent and potentially active groups prevalent in the Caprinae genomes. Additionally, our investigation revealed that most long noncoding genes (lncRNA) and protein-coding genes (PC) contain ERV-derived sequences. Specifically, we observed that ERV-derived sequences were present in approximately 75% of protein-coding genes and 81% of lncRNA genes in sheep. Similarly, in goats, ERV-derived sequences were found in approximately 74% of protein-coding genes and 75% of lncRNA genes. Our findings lead to the conclusion that the majority of ERVs in the Caprinae genomes can be categorized as fossils, representing remnants of past retroviral infections that have become permanently integrated into the genomes. Nevertheless, the identification of the Cap_ERV_20, Cap_ERV_21, Cap_ERV_24, and Cap_ERV_25 groups indicates the presence of relatively recent and potentially active ERVs in these genomes. These particular groups may contribute to the ongoing evolution of the Caprinae genome. The identification of putatively active ERVs in the Caprinae genomes raises the possibility of harnessing them for future genetic marker development. [ABSTRACT FROM AUTHOR]

Simple Summary: Retrotransposons in pigs account for approximately 37.13% of the genome, while long terminal repeats (LTRs) make up 7.56%. These LTR retrotransposons consist of two identical sequences that flank an internal protein-coding region, known as an endogenous retrovirus (ERV). When an insertion polymorphism integrates into a genomic region that harbors functional ERV elements, such as promoters, enhancers, and insulators, it may contribute to phenotypic variation. In this study, we explored the insertion polymorphisms generated by the mobilization of full-length ERVs (Fl-ERVs). Through comparative genomic analysis, we identified 18 insertion polymorphic sites that were generated by Fl-ERVs, and evaluated the genetic impact of one Fl-ERV insertion polymorphism in the STAB2-like gene. Endogenous retroviruses (ERVs) are one of the superfamilies of long terminal repeat retrotransposons (LTRs) in mice and humans. Approximately 8% of the pig genome is composed of sequences derived from LTRs. While the majority of ERVs in pigs have decayed, a small number of full-length copies can still mobilize within the genome. This study investigated the unexplored retroviral insertion polymorphisms (RIPs) generated by the mobilization of full-length ERVs (Fl-ERVs), and evaluated their impact on phenotypic variation to gain insights into the biological role of Fl-ERVs in pigs. Overall, 39 RIPs (insertions or deletions relative to the pig reference genome) generated by Fl-ERVs were predicted by comparative genomic analysis, and 18 of them were confirmed by PCR detection. Four RIP sites (D5, D14, D15, and D18) were further evaluated by population analysis, and all of them displayed polymorphisms in multiple breeds. The RIP site of ERV-D14, which is a Fl-ERV inserted in the STAB2-like gene, was further confirmed by sequencing. Population analysis of the polymorphic site of ERV-D14 reveals that it presents moderate polymorphism information in the Large White pig breed, and the association analysis reveals that the RIP of ERV-D14 is associated with age variations at 30 kg body weight (p < 0.05) and 100 kg body weight (p < 0.01) in the population of Large White pigs (N = 480). Furthermore, the ERV-D14 RIP is associated with changes in the expression of the target gene STAB2-like in the liver, backfat, and leaf fat in Sushan pigs. These data suggest that some Fl-ERVs are still mobilizing in the pig's genome, and contribute to genomic and phenotypic variations. [ABSTRACT FROM AUTHOR]

Simple Summary: Transposable elements (TEs) are mobile genetic elements that play vital role in defining and contributing to the size, shape and structure of both prokaryotic and eukaryotic genomes in nature. The piggyBac (PB), a superfamily of DNA transposons, has been isolated over the years from various organisms including insects, fungi and plants. These piggyBac transposon systems have high efficiency with a wide usage in the study of gene therapies, mutagenesis and transgenesis. Currently, there is limited information available on DNA transposons in small (compact) genomes of animals. Therefore, this study aims to annotate the PB transposons in small genomes of animals, revealing their evolution profiles in both vertebrate and invertebrate genomes. TEs, including DNA transposons, are major contributors of genome expansions, and have played a very significant role in shaping the evolution of animal genomes, due to their capacity to jump from one genomic position to the other. In this study, we investigated the evolution landscapes of PB transposons, including their distribution, diversity, activity and structure organization in 79 species of small (compact) genomes of animals comprising both vertebrate and invertebrates. Overall, 212 PB transposon types were detected from almost half (37) of the total number of the small genome species (79) investigated. The detected PB transposon types, which were unevenly distributed in various genera and phyla, have been classified into seven distinct clades or families with good bootstrap support (>80%). The PB transposon types that were identified have a length ranging from 1.23 kb to 9.51 kb. They encode transposases of approximately ≥500 amino acids in length, and possess terminal inverted repeats (TIRs) ranging from 4 bp to 24 bp. Though some of the transposon types have long TIRs (528 bp), they still maintain the consistent and reliable 4 bp target site duplication (TSD) of TTAA. However, PiggyBac-2_Cvir transposon originating from the Crassostrea virginica species exhibits a unique TSD of TATG. The TIRs of the transposons in all the seven families display high divergence, with a highly conserved 5′ end motif. The core transposase domains (DDD) were better conserved among the seven different families compared to the other protein domains, which were less prevalent in the vertebrate genome. The divergent evolution dynamics analysis also indicated that the majority of the PB transposon types identified in this study are either relatively young or old, with some being active. Additionally, numerous invasions of PB transposons were found in the genomes of both vertebrate and invertebrate animals. The data reveals that the PB superfamily is widely distributed in these species. PB transposons exhibit high diversity and activity in the small genomes of animals, and might play a crucial role in shaping the evolution of these small genomes of animals. [ABSTRACT FROM AUTHOR]

Novel active DNA transposons, such as Spy transposons from the PHIS superfamily, are identified through bioinformatics in this study. The native transposases cgSpy and cvSpy displayed transposition activities of approximately 85% and 35% compared to the hyperactive piggyBac transposase (hyPB). The cgSpy transposon showed unique characteristics, including a lack of overproduction inhibition and reduced efficiency for insertion sizes between 3.1 to 8.5 kb. Integration preferences of cgSpy are found in genes and regulatory regions, making it suitable for genetic manipulation. Evaluation in T-cell engineering demonstrated that cgSpy-mediated chimeric antigen receptor (CAR) modification is comparable to the PB system, indicating its potential utility in cell therapy. This study unveils the promising application of the active native transposase, Spy, from Colletes gigas, as a valuable tool for genetic engineering, particularly in T-cell manipulation., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Phototaxis phenomenon is fundamental and critical for optical manipulation of micro-objects. Here, we report the size-dependent negative or positive phototaxis behaviors for microdroplets containing interfacial energy absorber flying in a laser. The critical diameters for such negative-to-positive turnover are studied through both experiments and simulation with different liquids and absorbers, which establishes the mechanism and reveals the role of both the liquid and the absorber inside the microdroplets. This study offers new insight for the manipulation of the phototaxis behavior of micro-objects, showing potential applications in optical trapping and transporting systems that involve light-microdroplet interactions.