Stretchable, Programmable and Magnet-Insensitive Protonic Display Based on Integrated Ionic Circuit.

As a new approach to "More than Moore", integrated ionic circuits serve as a possible alternative to traditional electronic circuits, yet the integrated ionic circuit composed of functional ionic elements and ionic connections is still challenging. Herein, a stretchable and transparent ionic display module of the integrated ionic circuit has been successfully prepared and demonstrated by pixelating a proton-responsive hydrogel. It is programmed to excite the hydrogel color change by a Faraday process occurring at the electrode at the specific pixel points, which enables the display of digital information and even color information. Importantly, the display module exhibits stable performance under strong magnetic field conditions (1.7 T). The transparent and stretchable nature of such ionic modules also allows them to be utilized in a broad range of scenarios, which paves the way for integrated ionic circuits.

Metal Halides for High-Capacity Energy Storage.

High-capacity electrochemical energy storage systems are more urgently needed than ever before with the rapid development of electric vehicles and the smart grid. The most efficient way to increase capacity is to develop electrode materials with low molecular weights. The low-cost metal halides are theoretically ideal cathode materials due to their advantages of high capacity and redox potential. However, their cubic structure and large energy barrier for deionization impede their rechargeability. Here, the reversibility of potassium halides, lithium halides, sodium halides, and zinc halides is achieved through decreasing their dimensionality by the strong π-cation interactions between metal cations and reduced graphene oxide (rGO). Especially, the energy densities of KI-, KBr-, and KCl-based materials are 722.2, 635.0, and 739.4 Wh kg-1 , respectively, which are higher than those of other cathode materials for potassium-ion batteries. In addition, the full-cell with 2D KI/rGO as cathode and graphite as anode demonstrates a lifespan of over 150 cycles with a considerable capacity retention of 57.5%. The metal halides-based electrode materials possess promising application prospects and are worthy of more in-depth researches.

Bilayer Actuator with Overload Protection on the Basis of Semicrystalline Polyurethane.

Response to external stimuli plays a significant role in the environmental adaptation of living matters and intelligent devices. Most stimulus-response systems in nature can respond to appropriate stimuli, and inhibit the response under excessive stimuli, such as excessive heat or water, which can be called overload protection. However, even though various responsive materials have been developed for different stimuli, most of them are not protective against the overload stimuli. In this work, a bilayer actuator based on semicrystalline polyurethane is designed, which can respond differently to proper stimuli and excessive stimuli, i.e., water. This actuator can bend gradually under the proper stimulation of water, but will straighten and even bend reversely with excessive stimulation. The mechanism behind the reversible and adjustable actuator with overload protection is investigated both experimentally and theoretically, and the competition between dynamic factors and thermodynamic stability in the swelling process is considered the main cause.

Plasmon-induced magnetic anapole mode assisted strong field enhancement.

Optical metamaterials, sensing, nonlinear optics, and surface-enhanced spectroscopies have witnessed the remarkable potential of the anapole mode. While dielectric particles with a high refractive index have garnered significant attention in recent years, the exploration of plasmonic anapole modes with intense localized electric field enhancements in the visible frequency range remains limited. In this study, we present a theoretical investigation on the relationship between the strongest near-field response and magnetic anapole modes, along with their substantial enhancement of Raman signals from probing molecules. These captivating findings arise from the design of a practical metallic oblate spheroid-film plasmonic system that generates magnetic anapole resonances at frequencies within the visible-near-infrared range. This research not only sheds light on the underlying mechanisms in a wide range of plasmon-enhanced spectroscopies but also paves the way for innovative nano-device designs.

First Report of Anthracnose Caused by Colletotrichum ciggaro on Lonicera macranthoides Hand.-Mazz. in China.

Lonicera macranthoides Hand.-Mazz. is a traditional medicinal plant that is cultivated in Hunan, Yunnan, and Guizhou Provinces in China. In June 2020, a new leaf spot disease was observed on this plant in Longhui County, Shaoyang City, Hunan Province, China, where 14,000 hm2 of L. macranthoides had been planted. About 20% of the total cultivated area exhibited symptoms. Brown spots appeared on the leaves during the early stage and gradually expanded into irregular lesions, which became necrotic and dry. The whole plant withered and died in severe cases. To isolate the pathogen, the infected leaves were collected from different fields and washed with flowing sterile water. The small lesions were then cut and surface sterilized with 75% alcohol for 45 s followed by a 3 min treatment in 3% sodium hypochlorite. The lesions were rinsed five times in sterile water, incubated on potato dextrose agar (PDA) plates and cultured for 3-5 d at 28℃. In total, eleven isolates were obtained, and eight of them were Colletotrichum (isolation frequency 73%). Three representative isolates (JYH1, JYH2, and JYH5) were selected for further study. The fungus grew as circular white colonies, which then became grey. The older colonies looked like cotton and had dense aerial hyphae. The conidia were aseptate, transparent, cylindric, and thin walled, which measured 11.54 to 22.64 × 3.55 to 4.75 µm (n=100). Six genetic regions were amplified and sequenced to further confirm the identity of fungus. They included ß-tubulin (TUB2), the internal transcribed spacer (ITS), actin (ACT), chitin synthase (CHS), calmodulin (CAL) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). The sequences were submitted to GenBank (ITS: OQ746331; ON954583; OQ746334; TUB2: OQ772278; ON960155; OQ772279; CHS: OQ772280; ON960156; OQ772281; ACT: OQ772282; ON960157; OQ772283; CAL: OQ772284; ON960158; OQ772285; GAPDH: OQ772286; ON960159; OQ772287). The construction of a 6-gene joint phylogenetic tree analysis showed that the three isolates unambiguously clustered with Colletotrichum kahawae subsp. ciggaro strains C022-1 (GenBank: KJ001120.1, KJ001124.1, KJ001109.1, KJ001102.1, KJ001106.1, KJ001113.1) and R019 (GenBank: JN715847.1, KC860023.1, KC859980.1, KC859954.1, KC859972.1, KC859997.1), which was recently reclassified as C. cigarro (Cabral et al. 2020). Three representative isolates were used for the pathogenicity test on the young leaves of the whole plant. A sterile pin was used to prick the leaf epidermis, and 6 × 6 mm mycelial blocks that had been cultured on PDA for 7 d were placed on the leaf wounds. The controls were treated in the same manner except that sterile blocks of PDA were used. There were three replicates per treatment. All the plants used in the experiment were maintained at 28°C in a climate chamber. There was a 12 h photoperiod, and the chamber was kept at 80% relative humidity. Dark brown spots appeared at the sites of inoculation on the plants after 5 days. All the strains that were re-isolated from the lesions shared the same morphological characteristics and had the same type of colonies as the pathogen Colletotrichum ciggaro. Thus, Koch's postulates were fulfilled. C. ciggaro had been shown to cause anthracnose on Olea europaea L. (Weir et al. 2012), Mangifera indica L. (Ismail et al. 2015), Citrus reticulata L. (Perrone et al. 2016) and Areca catechu L. (Zhang et al. 2020). To our knowledge, this is the first report of C. ciggaro causing anthracnose on L. macranthoides in China and worldwide. This research provides a basis for further research to control epidemics of this disease.

Ultrafast attosecond-magnetic-field generation of the charge migration process based on HeH2+ and H2 + electronically excited by circularly polarized laser pulses.

The ultrafast process by the electron in molecular ions from one site or region to another that has come to be known as charge migration (CM), which is of fundamental importance to photon induced chemical or physical reactions. In this work, we study the electron current and ultrafast magnetic-field generation based on CM process of oriented asymmetric (HeH2+) and symmetric (H2 +) molecular ions. Calculated results show that they are ascribed to quantum interference of electronic states for these molecular ions under intense circularly polarized (CP) laser pulses. The two scenarios of (i) resonance excitation and (ii) direct ionization are considered through appropriately utilizing designed laser pulses. By comparison, the magnetic field induced by the scenario (i) is stronger than that of scenario (ii) for molecular ions. However, the scheme (ii) is very sensitive to the helicity of CP field, which is opposite to the scenario (i). Moreover, the magnetic field generated by H2 + is stronger than that by HeH2+ through scenario (i). Our findings provide a guiding principle for producing ultrafast magnetic fields in molecular systems for future research in ultrafast magneto-optics.

High throughput sequencing of whole transcriptome and construct of ceRNA regulatory network in RD cells infected with enterovirus D68.

BACKGROUND: With the advancement of sequencing technologies, a plethora of noncoding RNA (ncRNA) species have been widely discovered, including microRNAs (miRNAs), circular RNAs (circRNAs), and long ncRNAs (lncRNAs). However, the mechanism of these non-coding RNAs in diseases caused by enterovirus d68 (EV-D68) remains unclear. The goal of this research was to identify significantly altered circRNAs, lncRNAs, miRNAs, and mRNAs pathways in RD cells infected with EV-D68, analyze their target relationships, demonstrate the competing endogenous RNA (ceRNA) regulatory network, and evaluate their biological functions. METHODS: The total RNAs were sequenced by high-throughput sequencing technology, and differentially expressed genes between control and infection groups were screened using bioinformatics method. We discovered the targeting relationship between three ncRNAs and mRNA using bioinformatics methods, and then built a ceRNA regulatory network centered on miRNA. The biological functions of differentially expressed mRNAs (DEmRNAs) were discovered through GO and KEGG enrichment analysis. Create a protein interaction network (PPI) to seek for hub mRNAs and learn more about protein-protein interactions. The relative expression was verified using RT-qPCR. The effects of Fos and ARRDC3 on virus replication were confirmed using RT-qPCR, virus titer (TCID50/ml), Western blotting. RESULTS: 375 lncRNAs (154 upregulated and 221 downregulated), 33 circRNAs (32 upregulated and 1 downregulated), 96 miRNAs (49 upregulated and 47 downregulated), and 239 mRNAs (135 upregulated and 104 downregulated) were identified as differently in infected group compare to no-infected group. A single lncRNA or circRNA can be connected with numerous miRNAs, which subsequently coregulate additional mRNAs, according to the ceRNA regulatory network. The majority of DEmRNAs were shown to be connected to DNA binding, transcription regulation by RNA polymerase II, transcription factor, MAPK signaling pathways, Hippo signal pathway, and apoptosis pathway, according to GO and KEGG pathway enrichment analysis. The hub mRNAs with EGR1, Fos and Jun as the core were screened through PPI interaction network. We preliminarily demonstrated that the Fos and ARRDC3 genes can suppress EV-D68 viral replication in order to further verify the results of full transcriptome sequencing. CONCLUSION: The results of whole transcriptome analysis after EV-D68 infection of RD cells were first reported in this study, and for the first time, a ceRNA regulation network containing miRNA at its center was established for the first time. The Fos and ARRDC3 genes were found to hinder viral in RD cells. This study establishes a novel insight host response during EV-D68 infection and further investigated potential drug targets.

Shell-Isolated Nanoparticle-Enhanced Luminescence of Metallic Nanoclusters.

Metallic nanoclusters (NCs) have molecular-like structures and unique physical and chemical properties, making them an interesting new class of luminescent nanomaterials with various applications in chemical sensing, bioimaging, optoelectronics, light-emitting diodes (LEDs), etc. However, weak photoluminescence (PL) limits the practical applications of NCs. Herein, an effective and facile strategy of enhancing the PL of NCs was developed using Ag shell-isolated nanoparticle (Ag SHIN)-enhanced luminescence platforms with tuned SHINs shell thicknesses. 3D-FDTD theoretical calculations along with femtosecond transient absorption and fluorescence decay measurements were performed to elucidate the enhancement mechanisms. Maximum enhancements of up to 231-fold for the [Au7Ag8(C≡CtBu)12]+ cluster and 126-fold for DNA-templated Ag NCs (DNA-Ag NCs) were achieved. We evidenced a novel and versatile method of achieving large PL enhancements with NCs with potential for practical biosensing applications for identifying target DNA in ultrasensitive surface analysis.

Microwave coherent control of ultracold ground-state molecules formed by short-range photoassociation.

We report the observation of microwave coherent control of rotational states of ultracold 85Rb133Cs molecules formed in their vibronic ground state by short-range photoassociation. Molecules are formed in the single rotational state X(v = 0, J = 1) by exciting pairs of atoms to the short-range state (2)3Π0-(v = 11, J = 0), followed by spontaneous decay. We use depletion spectroscopy to record the dynamic evolution of the population distribution and observe clear Rabi oscillations while irradiating on a microwave transition between coupled neighbouring rotational levels. A density-matrix formalism that accounts for longitudinal and transverse decay times reproduces both the dynamic evolution during the coherent process and the equilibrium population. The coherent control reported here is valuable both for investigating coherent quantum effects and for applications of cold polar molecules produced by continuous short-range photoassociation.

Strong coupling between magnetic resonance and propagating surface plasmons at visible light frequencies.

Light-matter interactions in nanostructures have shown great potential in physics, chemistry, surface science, materials science, and nanophotonics. Herein, for the first time, the feasibility of strong coupling between plasmon-induced magnetic resonant and propagating surface plasmonic modes at visible light frequencies is theoretically demonstrated. Taking advantage of the strong coupling between these modes allowed for a narrow-linewidth hybrid mode with a huge electromagnetic field enhancement to be acquired. This work can serve as a promising guide for designing a platform with strong coupling based on magnetic resonance at visible and even ultraviolet light frequencies and also offers an avenue for further exploration of strong light-matter interactions at the nanoscale.

Neuropilin1 silencing impairs the proliferation and migration of cells in pancreatic cancer.

BACKGROUND: Neuropilin1 (NRP1) participates in cancer cell proliferation, migration, and metastasis as a multifunctional co-receptor by interacting with multiple signal pathways, but few studies have addressed the precise function of NRP1 in pancreatic cancer (PACA) cells. We aimed to study whether NRP1 gene silencing involved in the proliferation and migration of PACA cells in vitro. METHODS: A lentiviral vector expressing NRP1 shRNA was constructed and transfected into human PACA cells (CFPAC-1 and PANC-1). The expression of NRP1 protein and mRNA was detected by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) assay, respectively. CCK-8 assay, wound healing assay, and transwell assay were conducted to examine the effect of NRP1 silencing on cells proliferation and migration capability. RESULTS: Results of qRT-PCR and Western blot showed successfully established, stably transfected shRNA-NRP1 cells in PACA cells. The proliferation capacity of PACA cells in NRP1 shRNA group was lower significantly than that in the negative control (NC) group (P < .05). The invasion and migration capability of PACA cells in NRP1 shRNA group was lower significantly than that in the NC group (P < .01). CONCLUSIONS: NRP1-shRNA lentiviral interference vectors can effectively decrease NRP1 gene expression in PACA cells, thereby inhibiting cells proliferation and migration, which provides a basis for finding a valuable therapeutic target for PACA therapy.

Different Sequevars of Ralstonia pseudosolanacearum Causing Bacterial Wilt of Bidens pilosa in China.

Bidens pilosa is an invasive weed that threatens the growth of crops and biodiversity in China. In 2017, suspected bacterial wilt of B. pilosa was discovered in Qinzhou and Beihai, Guangxi, China. A variety of weeds are considered as reservoirs harboring bacterial wilt pathogens, but most do not show obvious symptoms in the field. Identifying the classification status of the B. pilosa bacterial wilt pathogen and exploring its geographical origin might be helpful for clarifying the role of weeds in the circulation of the disease. Phylotyping, sequevar analysis, and cross inoculation of pathogens isolated from B. pilosa and nearby peanut (Arachis hypogaea), balsam gourd (Momordica charantia), and eucalyptus (Eucalyptus robusta) plants were carried out. Three isolates of B. pilosa (Bp01, Bp02, and Bp03) were identified as Ralstonia pseudosolanacearum, race 1, biovar 3, and phylotype I, and belonged to sequevars 17 and 44, and an unknown sequevar. The sequevars isolated from B. pilosa were not completely consistent with those of the nearby hosts, and the virulence of these isolates differed when cross inoculated. The Bp03 sequevar was different from peanut isolate sequevars in the same field and was not identical to any previously designated sequevars. The isolates from B. pilosa and other nearby hosts displayed low or no virulence toward their cross hosts (with wilt incidences less than 33.33%). An exception to this was the isolates from B. pilosa, which displayed high virulence toward eucalyptus (with a wilt incidence of 70.00 to 100.00%). This is the first report of different sequevars of R. pseudosolanacearum causing typical bacterial wilt symptoms in B. pilosa in the field.

First Report of Stagonosporopsis vannaccii Causing Leaf Spot on Crassocephalum crepidioides in China.

Crassocephalum crepidioides (Benth.) S. Moore, native to tropical Africa, is an important invasive weed in many countries, seriously threatening the safety of agricultural ecosystem. During December 2018, 100% of C. crepidioides plants exhibited leaf spots in the Kudzu (Pueraria lobata) garden in Tianlin County, Baise City, Guangxi, China (24°40'20.42″N, 106°11'33.51″E), but Kudzu was not affected by this disease. The leaf spots appeared as small brown spots surrounded by a yellow-green halo initially, enlarged to subrotund or irregular in shape, slightly sunken, then developed as a dark brown to dark spot with grey-white necrotic center (Supplementary Fig. 1 a,b), and exuded an orange droplet under high humidity conditions (Supplementary Fig. 1 c). Symptomatic leaf tissues were cut into small pieces (5 x 5 mm) from the junction of necrotic and healthy tissues, and small pieces were disinfected in 75% ethanol solution for 30 s and 0.1% mercury dichloride for 30 sec, then rinsed with sterile water 3 times. These tissues were plated onto potato dextrose agar (PDA) medium and incubated in a thermostatic incubator at 28°C under natural sunlight conditions. Four isolates with similar morphological features were obtained after purification. Colonies of these isolates exhibited creme-orange margins and aerial mycelium was sparse. The colonies formed concentric circles on the surface that were fusco-black, violet-slate and vinaceus-grey (from centre to edge), fusco-black on the reverse after 7 days (Supplementary Fig. 2 a,b), and then the pycnidia and conidia produced for about 30 days (Supplementary Fig. 2 c). Pycnidia of representative isolate YTH-12 were black, subglobose, and unilocular, 95.60-168.27 µm (average 128.32 µm) (n = 40) in diameter. The ostiole was single and central, slightly papillate to papillate and occasionally rostrate (Supplementary Fig. 2 d). Conidia were hyaline, oval to elliptical, aseptate, 2.30 to 5.83 × 1.42 to 3.50 µm (average, 4.36 × 2.03 µm) (n = 50) (Supplementary Fig. 2 e). These morphological characters are consistent with those described for Stagonosporopsis vannaccii (Crous et al. 2019). To further identify the isolate YTH-12, the rDNA internal transcribed spacer (ITS) region, 28s large subunit ribosomal RNA (LSU), RNA polymerase II second largest subunit (RPB2) gene and ß-tubulin (TUB2) gene were amplified by polymerase chain reaction using the primer pairs ITS1/ITS4 (White et al. 1990), LR0R (Rehner and Samuels 1994)/LR7 (Vilgalys and Hester 1990), Btub2Fd/Btub4Rd (Woudenberg et al. 2009) and RPB2-5F2 (Sung et al. 2007)/fRPB2-7cR (Liu et al. 1999), respectively. The PCR products were purified and sequenced by Sangon Biotech Co. Ltd. (Shanghai, China). The sequences were deposited in GenBank (accession nos. MN892355, MN893911, MN905510 and MN905511). The ITS (522 bp), LSU (1313 bp), TUB2 (380 bp) and RPB2 (1193 bp) nucleotide sequences showed 100% identity to S. vannaccii strain LFNO148 (accession nos. MK519453, MK519452, MK519454 and MN534891). Phylogenetic analysis based on the multi-locus sequences of ITS, LSU, RPB2 and TUB2 was performed in MEGA version 6.0 (Chen et al. 2015). The relative stability of the branches was evaluated by bootstrapping with 1000 replications. The isolate YTH-12 was placed in the same clade as S. vannaccii with 100% bootstrap support. Based on morphology and molecular analyses, this pathogen was identified as S. vannaccii. To satisfy Koch's postulates, the isolate YTH-12 was inoculated on leaves of C. crepidioides plants. Twenty punctured leaves and twenty unwounded leaves were inoculated with a 5-mm-diameter mycelial disc, respectively. Leaves inoculated with sterile PDA discs were used as blank controls. Plants were maintained in a growth chamber (25°C-28°C and relative humidity 80%-90%). Brown spots were observed on inoculated leaves (both punctured and unwounded) about 30 hours after inoculation and typical symptoms appeared about 55 hours after inoculation (Supplementary Fig. 1 d), and the diseased leaves produced black pycnidia and orange droplet 10 days after inoculation (Supplementary Fig. 1 e). All inoculated leaves developed symptoms similar to those on the naturally infected plants in the garden and the disease incidence reached 100%, whereas the control leaves remained symptomless (Supplementary Fig. 1 f). The same fungus was re-isolated from inoculated leaves. To our knowledge, this is the first report of S. vannaccii causing leaf spot on C. crepidioides in China. So far, Stagonosporopsis vannaccii has been reported as a plant pathogenic fungus only in Brazil, causing anthracnose symptoms on pods of soybean (Crous et al. 2019). Crassocephalum crepidioides is a widely distributed weed. If S. vannaccii has strong host specificity, it is possible to be used as a biocontrol fungus to control the weed. Conversely, if the fungus has a wider host range, C. crepidioides may act as a good bridge to spread the pathogen. This study helps to deepen the understanding of S. vannaccii and its associated plant diseases.

Multispectroscopic exploration and molecular docking analysis on interaction of eriocitrin with bovine serum albumin.

Eriocitrin is a flavanone glycoside, which exists in lemon or lime citrus fruits. It possesses antioxidant, anticancer, and anti-allergy activities. In order to investigate the pharmacokinetics and pharmacological mechanisms of eriocitrin in vivo, the interaction between eriocitrin and bovine serum albumin (BSA) was studied under the simulated physiological conditions by multispectroscopic and molecular docking methods. The results well indicated that eriocitrin and BSA formed a new eriocitrin-BSA complex because of intermolecular interactions, which was demonstrated by the results of ultraviolet-visible (UV-vis) absorption spectra. The intrinsic fluorescence of BSA was quenched by eriocitrin, and static quenching was the quenching mechanism. The number of binding sites (n) and binding constant (Kb ) at 310 K were 1.22 and 2.84 × 106  L mol-1 , respectively. The values of thermodynamic parameters revealed that the binding process was spontaneous, and the main forces were the hydrophobic interaction. The binding distance between eriocitrin and BSA was 3.43 nm. In addition, eriocitrin changed the conformation of BSA, which was proved by synchronous fluorescence and circular dichroism (CD) spectra. The results of site marker competitive experiments suggested that eriocitrin was more likely to be inserted into the subdomain IIA (site I), which was further certified by molecular docking studies.

Dark Ionic Liquid for Flexible Optoelectronics.

Owing to a wide visual angle, few aberrations, and great depth of focus, flexible optoelectronics have become one subject of intense investigation for rescue equipment and endoscopy tools. Ionic liquids are rising as a kind of fluidic "semiconductor" with advantages of high flexibility and self-healing. However, challenges in the molecular design of photoresponsive ionic liquids impede the exploration of ionic liquids as intrinsic flexible liquid optoelectronics. This work demonstrated an imidazole-based ionic liquid covalently linked with a polypyrrole oligomer by alkyl chains. Such an ionic liquid has wide absorption from the visible light range to the near-infrared light range. The imidazole moiety acts as an electrical conductor which is thermally responsive. On the other hand, the polypyrrole segment serving as a light antenna is able to convert light energy to thermal heat. The alkyl linker tailors the energy transfer between polypyrrole and an imidazole cation. Negligible molecular aggregation and phase separation are attributed to the preservation of the fluidic nature at room temperature. This photoresponsive ionic liquid is successfully exploited as a flexible light detector that is adaptable to special sensing tests in bending states.

Inherently magnetic hydrogel for data storage based on the magneto-optical Kerr effect.

In this data explosion age, a large amount of data is generated every day. Such a fast data growth has aroused great interest in the field of data storage. Conventional data storage materials are mainly composed of hard and brittle materials but they may break in the case of mechanical operations, causing irreversible data loss. In this work, efforts have been devoted to fabricating a flexible and stretchable double network hydrogel for data storage based on the magneto-optical Kerr effect. The hydrogel possesses a storage modulus of over 104 Pa and remains unbroken under a strain of 3000%. The surface of the hydrogel is patterned with diamagnetic parts and paramagnetic parts alternately. When placed under a magnetic field, the surface of the hydrogel reflects the incident laser beam and changes the polarization plane of the reflected light. The outstanding flexibility and inherent magnetic properties of this hydrogel lay the groundwork for data storage and guarantee data safety.

A Polypyrrole Elastomer Based on Confined Polymerization in a Host Polymer Network for Highly Stretchable Temperature and Strain Sensors.

For the purpose of stretchable electronics, broad interests have been paid to elastic conductors by which high tensile strain over 100% can be readily achieved. Here, a scalable-processing, dyeing-like strategy for highly stretchable polypyrrole elastomer (1450% in strain) is conceived without particular topological design. This approach effectively improves the mechanical properties of the classic insoluble polypyrrole by confined polymerization within an elastic polymer network. In terms of the easy processing, it is technically possible to prepare stretchable electronics with arbitrary shape and size for wearable electronics with low cost. The mechanism of interpenetrated networks coexisting with microphase separation is comprehensively illustrated at molecular scale. The as-fabricated polypyrrole elastomers are utilized as temperature or strain sensors for automatic fishing and region-distinct dual signal sensing. Further integration of multiple sensors offers immediate alarm for old people falling at home, which thereby proves its promising potential in practical applications.

A Degradable and Recyclable Photothermal Conversion Polymer.

Decomposition and repolymerization of conjugated polymers offer great promise for developing recyclable photothermal conversion materials, which yet remain challenging. Herein, a crosslinked conjugated polymer based on a dynamic covalent bond of Schiff base is developed. This polymer possesses photothermal conversion efficiency as high as 90.4 %. Decomposition of the polymer under specialized conditions is corroborated by various characterizations. The kinetics study is also investigated to understand this degradation process. Furthermore, those decomposed species can be repolymerized back to conjugated polymers which possess the same photothermal conversion efficiency as the pristine polymer. Such a degradable and recyclable photothermal polymer is successfully used as a heat source for photothermal-electrical conversion to generate Seebeck voltage under either near infrared (NIR) irradiation or solar illumination.

Refreshing Rubbers as Customized Photothermal Conversion Materials through Post-Darkening Modeling Production.

Organic conjugated polymers with low energy bandgaps are emerging as a particular class of near-infrared (NIR) photothermal conversion materials. However, these polymers routinely possess high phase transition temperatures due to the rigid skeleton and strong intermolecular interactions. Conjugated polymers can rarely be thermally processed at low temperature, especially below 100 °C. This work formulates a concept of post-darkening modeling production (p-DMP) by which the thermoplastic non-conjugated trans-polyisoprene (TPI) is refreshed into a photothermal conversion material with high light use efficiency. Two steps, including the customizable shaping at low temperature and iodine vapor-tailored "darkening", ensure the ease of preparing photothermal conversion devices with desirable topologies. A few characterizations, with the combination of density functional theory (DFT) calculations, provide reasonable explanations for understanding the "darkening" process of TPI in iodine atmosphere. In particular, the p-DMP is successfully extended to three-dimension (3D) printing, opening an avenue to fabricate personalized photothermal products, for example, a sunlight-directed physiotherapy device for healthcare of articular tissues.