Phylogenetic, Expression, and Bioinformatic Analysis of the ABC1

We studied 17 ABC1 genes in Populus trichocarpa, all of which contained an ABC1 domain consisting of about 120 amino acid residues. Most of the ABC1 gene products were located in the mitochondria or chloroplasts. All had a conserved VAVK-like motif and a DFG motif. Phylogenetic analysis grouped the genes into three subgroups. In addition, the chromosomal locations of the genes on the 19 Populus chromosomes were determined. Gene structure was studied through exon/intron organization and the MEME motif finder, while heatmap was used to study the expression diversity using EST libraries. According to the heatmap, PtrABC1P14 was highlighted because of the high expression in tension wood which related to secondary cell wall formation and cellulose synthesis, thus making a contribution to follow-up experiment in wood formation. Promoter cis-element analysis indicated that almost all of the ABC1 genes contained one or two cis-elements related to ABA signal transduction pathway and drought stress. Quantitative real-time PCR was carried out to evaluate the expression of all of the genes under abiotic stress conditions (ABA, CdCl2, high temperature, high salinity, and drought); the results showed that some of the genes were affected by these stresses and confirmed the results of promoter cis-element analysis

Space advanced technology demonstration satellite

The Space Advanced Technology demonstration satellite (SATech-01), a mission for low-cost space science and new technology experiments, organized by Chinese Academy of Sciences (CAS), was successfully launched into a Sun-synchronous orbit at an altitude of similar to 500 km on July 27, 2022, from the Jiuquan Satellite Launch Centre. Serving as an experimental platform for space science exploration and the demonstration of advanced common technologies in orbit, SATech-01 is equipped with 16 experimental payloads, including the solar upper transition region imager (SUTRI), the lobster eye imager for astronomy (LEIA), the high energy burst searcher (HEBS), and a High Precision Magnetic Field Measurement System based on a CPT Magnetometer (CPT). It also incorporates an imager with freeform optics, an integrated thermal imaging sensor, and a multi-functional integrated imager, etc. This paper provides an overview of SATech-01, including a technical description of the satellite and its scientific payloads, along with their on-orbit performance

Gene Structures, Classification, and Expression Models of the DREB

We identified 75 dehydration-responsive element-binding (DREB) protein genes in Populus trichocarpa. We analyzed gene structures, phylogenies, domain duplications, genome localizations, and expression profiles. The phylogenic construction suggests that the PtrDREB gene subfamily can be classified broadly into six subtypes (DREB A-1 to A-6) in Populus. The chromosomal localizations of the PtrDREB genes indicated 18 segmental duplication events involving 36 genes and six redundant PtrDREB genes were involved in tandem duplication events. There were fewer introns in the PtrDREB subfamily. The motif composition of PtrDREB was highly conserved in the same subtype. We investigated expression profiles of this gene subfamily from different tissues and/or developmental stages. Sixteen genes present in the digital expression analysis had high levels of transcript accumulation. The microarray results suggest that 18 genes were upregulated. We further examined the stress responsiveness of 15 genes by qRT-PCR. A digital northern analysis showed that the PtrDREB17, 18, and 32 genes were highly induced in leaves under cold stress, and the same expression trends were shown by qRT-PCR. Taken together, these observations may lay the foundation for future functional analyses to unravel the biological roles of Populus’ DREB genes

Identification and expression analysis of the heat shock transcription factor (HSF) gene family in Populus trichocarpa

Abstract In plants, heat shock transcription factors (HSFs) play key roles in regulating the heat shock (HS) response. Therefore, the genes encoding HSFs are important for adaptation to high temperatures and for tolerance to other abiotic stresses. There have been many studies on these genes in herbaceous plants, but few on the HSF family in woody plants. In this study, we identified 31 HSF genes in Populus trichocarpa and investigated their phylogenetic relationships with HSF genes in Arabidopsis and rice. Analyses of chromosomal duplications revealed that tandem/segmental duplications contributed to the expansion of the HSF gene family in P. trichocarpa. Gene structure was analyzed by investigating exon/intron organization and by using the MEME motif finder. Changes in gene expression were investigated using exPlot and digital northern analyses. Interestingly, nine of the HSF genes showed significant variations in expression patterns, suggesting that they have roles in stress responses. We evaluated changes in the transcript levels of the HSFs in response to abiotic stresses (heat, cadmium, salt, abscisic acid, and drought stresses) by analyzing log 2 fold change data. The transcript levels of the PoptrHSFA4a, PoptrHSFA4b and PoptrHSFA5a genes markedly increased in response to a wide range of stresses. The results of this study provide further information for cloning and expression of HSF genes, and for functional studies on the roles of these genes during development and in the responses to various environmental stimuli. Our results may help researchers design more efficient strategies to study the P. trichocarpa HSF family

Hydrogel‐Reactive‐Microenvironment Powering Reconfiguration of Polymer Architectures

Abstract Reconfiguration of architected structures has great significance for achieving new topologies and functions of engineering materials. Existing reconfigurable strategies have been reported, including approaches based on heat, mechanical instability, swelling, origami/kirigami designs, and electromagnetic actuation. However, these approaches mainly involve physical interactions between the host materials and the relevant stimuli. Herein, a novel, easy‐manipulated, and controllable reconfiguration strategy for polymer architectures is proposed by using a chemical reaction of host material within a hydrogel reactive microenvironment. 3D printed polycaprolactone (PCL) lattices transformed in an aqueous polyacrylamide (PAAm) hydrogel precursor solution, in which ultraviolet (UV) light triggered heterogeneous grafting polymerization between PCL and AAm. In situ microscopy shows that PCL beams go through volumetric expansion and cooperative buckling, resulting in transformation of PCL lattices into sinusoidal patterns. The transformation process can be tuned easily and patterned through the adjustment of the PCL beam diameter, unit cell width, and UV light on–off state. Controlling domain formation is achieved by using UV masks. This framework enables the design, fabrication, and programming of architected materials and inspires the development of novel 4D printing approaches

Study on electrical conductivity and microwave absorption properties of CNTs/CB/PMMA nanocomposites foam

In order to study the conductive and microwave absorption performance of multi-dimensional multiphase filler conductive foam composites, carbon nanotubes (CNTs)/carbon black (CB)/polymethyl methacrylate (PMMA) nanocomposites with different porosity were fabricated via supercritical carbon dioxide (ScCO _2 ) one-step physical constraint foaming technology. The effects of filler component and porosity on the conductivity and absorbing properties of CNTs/PMMA/CB composite foam were studied. The Monte-Carlo method was used to study the percolation of composites and the effect of introduced microcells on the conductive network of multi-dimensional fillers. The results revealed that the volume conductivity of CNTs(3 vol%)/PMMA composites increased from 0.88 S m ^−1 to 3.31 S m ^−1 after the addition of 1 vol% CB. CNTs and CB had obvious synergistic effect on improving the conductivity of the composites, and the microwave absorption efficiency rose from 12.6 dB to 17.2 dB. With the increase of porosity, the electromagnetic wave absorption peak of CNTs/CB/PMMA composite foam moved to low frequency, while the conductivity showed a first rise and then a decline. The simulated percolation probability obtained by representative volume element (RVE) with different porosity also showed a similar trend, which turned out that with the increase of porosity, the effect of microcells on the convertion of conductive network construction from promoting to inhibiting

60-nt DNA Direct Detection without Pretreatment by Surface-Enhanced Raman Scattering with Polycationic Modified Ag Microcrystal Derived from AgCl Cube

Direct detection of long-strand DNA by surface-enhanced Raman scattering (SERS) is a valuable method for diagnosis of hereditary diseases, but it is currently limited to less than 25-nt DNA strand in pure water, which makes this approach unsuitable for many real-life applications. Here, we report a 60-nt DNA label-free detection strategy without pretreatment by SERS with polyquaternium-modified Ag microcrystals derived from an AgCl cube. Through the reduction-induced decomposition, the size of the about 3 × 3 × 3 μm3 AgCl cube is reduced to Ag, and the surface is distributed with the uniform size of 63 nm silver nanoparticles, providing a large area of a robust and highly electromagnetic enhancement region. The modified polycationic molecule enhances the non-specific electrostatic interaction with the phosphate group, thereby anchoring DNA strands firmly to the SERS enhanced region intactly. As a result, the single-base recognition ability of this strategy reaches 60-nt and is successfully applied to detect thalassemia-related mutation genes

60-nt DNA Direct Detection without Pretreatment by Surface-Enhanced Raman Scattering with Polycationic Modified Ag Microcrystal Derived from AgCl Cube

Direct detection of long-strand DNA by surface-enhanced Raman scattering (SERS) is a valuable method for diagnosis of hereditary diseases, but it is currently limited to less than 25-nt DNA strand in pure water, which makes this approach unsuitable for many real-life applications. Here, we report a 60-nt DNA label-free detection strategy without pretreatment by SERS with polyquaternium-modified Ag microcrystals derived from an AgCl cube. Through the reduction-induced decomposition, the size of the about 3 × 3 × 3 μm3 AgCl cube is reduced to Ag, and the surface is distributed with the uniform size of 63 nm silver nanoparticles, providing a large area of a robust and highly electromagnetic enhancement region. The modified polycationic molecule enhances the non-specific electrostatic interaction with the phosphate group, thereby anchoring DNA strands firmly to the SERS enhanced region intactly. As a result, the single-base recognition ability of this strategy reaches 60-nt and is successfully applied to detect thalassemia-related mutation genes

A hierarchical salt-rejection strategy for sustainable and high-efficiency solar-driven desalination

Solar steam generation (SSG) is widely regarded as one of the most sustainable technologies for seawater desalination. However, salt fouling severely compromises the evaporation performance and lifetime of evaporators, limiting their practical applications. Herein, we propose a hierarchical salt-rejection (HSR) strategy to prevent salt precipitation during long-term evaporation while maintaining a rapid evaporation rate, even in high-salinity brine. The salt diffusion process is segmented into three steps—insulation, branching diffusion, and arterial transport—that significantly enhance the salt-resistance properties of the evaporator. Moreover, the HSR strategy overcomes the tradeoff between salt resistance and evaporation rate. Consequently, a high evaporation rate of 2.84 ​kg ​m−2 ​h−1, stable evaporation for 7 days cyclic tests in 20 ​wt% NaCl solution, and continuous operation for 170 ​h in natural seawater under 1 sun illumination were achieved. Compared with control evaporators, the HSR evaporator exhibited a >54% enhancement in total water evaporation mass during 24 ​h continuous evaporation in 20 ​wt% salt water. Furthermore, a water collection device equipped with the HSR evaporator realized a high water purification rate (1.1 ​kg ​m−2 ​h−1), highlighting its potential for agricultural applications