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To explore the role of the membrane permease â ¡B (Eâ ¡B) gene of Listeria pathogenicity island 4 (LIPI-4) in the virulence of Listeria monocytogenes, both an Eâ ¡B deletion strain (∆Eâ ¡B) and a complemented strain were constructed. In vitro experiments demonstrated that Eâ ¡B deletion affected the biofilm formation ability of the wild-type strain (Lm928). Moreover, this deletion decreased the intracellular proliferation abilities of L. monocytogenes. Mice infected with ∆Eâ ¡B survived longer and experienced less weight loss on days 1, 2, and 3 post-infection. The bacterial load in the liver tissue of ∆Eâ ¡B-infected mice was significantly reduced, and a considerable decrease in the blood levels of inflammatory cytokines IL-ß, IL-6, IL-10, and TNF-α were observed. Following Eâ ¡B deletion, 65% (13/20) of genes were downregulated, 25% (5/20) were upregulated, and 10% (2/20) showed no change. These findings suggest that Eâ ¡B deletion may reduce both the in vivo and in vitro virulence levels as well as the biofilm formation ability of Lm928 by downregulating the transcription levels of genes associated with virulence and biofilm formation. These findings provide a foundation for further examining the pathogenic mechanisms of LIPI-4 and Eâ ¡B in L. monocytogenes.
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Circular aptamers are promising candidates for analytical and therapeutic applications due to their enhanced biological and structural stability. However, the process of circular aptamer selection remains a great challenge, as it requires multiple rounds of binding-separation-amplification that involves issues with nonspecific binding and amplification bias. Here, we develop a highly practical solution for reliable selection of circular aptamers in a single round based on magnetosome-like magnetic chain cross-linked graphene oxide (separation efficiency ≈ 105). High-affinity aptamer candidates can be rapidly selected from a preenriched circular DNA library, while low-affinity candidates are effectively adsorbed and separated by magnetosome-like magnetic chain cross-linked graphene oxide. With lipopolysaccharide as a representative model, the single-round selected lipopolysaccharide circular aptamer has been identified to have a high binding affinity with a Kd value of low to nanomolar range. Using this method, circular aptamers for protein and small-molecule targets were also successfully generated. We envision that this approach will accelerate the discovery of various new circular aptamers and open up a new avenue for analytical and therapeutic studies.
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INTRODUCTION: MicroRNAs (miRNAs) involve in destabilising messenger RNA or repressing translation of target molecules. Ginger-derived exosome-like nanoparticles (GELNs) play a crucial role in modulating intestinal inflammation. Moreover, GELNs contain highly heterogeneous miRNA. However, the role of miRNAs derived from GELNs in immunomodulation remains unclear. OBJECTIVES: This study aimed to elucidate the molecular basis of the unique biological effects mediated by miRNA derived from GELNs on macrophages. METHODS: GELNs were isolated using a combination of commercial exosome isolation kits and the differential centrifugation method, and the lipid composition of GELNs was determined using liquid chromatography-mass spectrometry. Subsequently, PKH26 labelled GELNs were taken up by macrophages. Furthermore, the modulation of inflammatory and immune responses by GELNs or osa-miR164d was assessed through the RNA-seq, RT-qPCR, online databases, and dual luciferase reporter assays to explore the underlying mechanisms of osa-miR164d. Biomimetic exosomes loaded with osa-miR164d were prepared using a microfluidic mixing device and systematically characterized. The therapeutic effects of osa-miR164d on relieving colitis were evaluated. RESULTS: We report for the first time that GELNs-derived osa-miR164d is a regulatory factor of reprogramming macrophage polarization, thereby inhibiting the intestinal inflammatory response. Mechanistically, osa-miR164d directly targets the 3'-UTRs of TAB1, which regulates macrophage polarization through the downregulation of NF-κB expression. In addition, We have designed a biomimetic exosome mimicking GELNs to deliver osa-miR164d (osa-miR164d-MGELNs). Notably, the osa-miR164d-MGELNs can efficiently reprogram macrophages to alleviate colitis-related symptoms. CONCLUSION: Our findings enhance the systematic understanding of how GELNs-derived osa-miR164d mediates cross-kingdom communication and provide an original engineering paradigm for mimicking GELNs to transfer miRNA.
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Semi-arid ecosystems have been shown to dominate over tropical forests in determining the trend and interannual variability of land carbon (C) sink. However, the magnitude and variability of ecosystem C balance remain largely uncertain for temperate semi-arid shrublands at the decadal scale. Using eddy-covariance and micro-meteorological measurements, we quantified the interannual variation in net ecosystem production (NEP) and its components, gross primary production (GPP) and ecosystem respiration (Reco, i.e., the sum of autotrophic and heterotrophic respiration), in a semi-arid shrubland of the Mu Us Desert, northern China during 2012-2022. This shrubland was an overall weak C sink over the 11 years (NEP = 12 ± 46 g C m-2 yr-1, mean ± SD). Annual NEP ranged from -66 to 77 g C m-2 yr-1, with the ecosystem frequently switching between being an annual C sink and a C source. GPP was twice as sensitive as Reco to prolonged dry seasons, leading to a close negative relationship between annual NEP and dry-season length (R2 = 0.80, P < 0.01). Annual GPP (R2 = 0.51, P = 0.01) and NEP (R2 = 0.58, P < 0.01) were positively correlated with annual rainfall. Negative annual NEP (the ecosystem being a C source) tended to occur when the dry season exceeded 50 d yr-1 or rainfall dropped below 280 mm yr-1. Increases in dry-season length strengthened the effects of low soil moisture relative to high vapor pressure deficit in constraining NEP. Both GPP and NEP were more closely correlated with C uptake amplitude (annual maximum daily values) than with C uptake period. These findings indicate that dry-season extension under climate change may reduce the long-term C sequestration in semi-arid shrublands. Plant species adapted to prolonged dry seasons should be used in ecosystem restoration in the studied area to enhance ecosystem functions.
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Introduction: This study investigated the effects of maggot antimicrobial peptides on growth performance, blood parameters, immune organ index, and cecum microbial diversity in yellow broilers. Methods: The addition of 100-300 mg/kg maggots antimicrobial peptides to the corn-soybean meal basal diet was evaluated. Two hundred and forty one-day-old yellow-feathered broilers were randomly divided into four groups (60 chickens in each group): basal diet group (BC group), basal diet group + 100, 200, 300 mg/kg maggots antimicrobial peptides (MDAL group, MDAM group, and MDAH group). Results: The result showed that the average daily feed intake (ADFI) of the BC group, MDAM group, and MDAH group was higher than that of the MDAL group (P > 0.05), the average daily gain of MDAM group and MDAH group was significantly higher than that of BC group and MDAL group (P < 0.05), but the feed-weight ratio (F/G) was significantly lower than that of BC group (P < 0.05). The total protein (TP) content in the MDAM group and MDAH group was significantly higher than that in the BC group (P < 0.05), and the albumin (ALB) content in the MDAH group was higher than that in the BC group (P > 0.05). The contents of IgA and IgG in the MDAH group were significantly higher than those in the BC group (P < 0.05). In contrast, the content of alanine aminotransferase (ALT) in the MDAH group was significantly lower than that in the BC group (P < 0.05). The thymus and spleen indexes of the MDAH group were significantly higher than those of the BC group (P < 0.05). 16S rDNA sequencing results showed that Bacteroidota and Bacteroides were the dominant phylum and genus of cecal microorganisms at the phylum and genus levels, respectively. Cecum microorganisms are mainly involved in biological processes such as energy production and conversion, amino acid transport and metabolism, and carbohydrate transport and metabolism. Discussion: It was concluded that adding different doses of maggot antimicrobial peptide to the basal diet could improve yellow-feathered broilers' growth and immune performance and change the cecum flora. The appropriate dose of antimicrobial peptide addition was 300 mg/kg.
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There is an increasing demand for prenatal paternity testing in the forensic applications, which identify biological fathers before the birth of children. Currently, one of the most effective and safe Non-Invasive Prenatal Paternity Testing (NIPPT) methods is high-throughput Next-Generation Sequencing (NGS)-based SNP genotyping of cell-free DNA in maternal peripheral blood. To the best of our knowledge, nearly all methods being used in such applications are based on traditional postnatal paternity tests and/or statistical models of conventional polymorphism sites. These methods have shown unsatisfactory performance due to the uncertainty of fetal genotype. In this study, we propose a cutting-edge methodology called the Prenatal paternity Test Analysis System (PTAS) for cell-free fetal DNA-based NIPPT using NGS-based SNP genotyping. With the implementation of our proposed PTAS methodology, 63 out of 64 early-pregnancy (i.e., less than seven weeks) samples can be precisely identified to determine paternity, except for one sample that does not meet quality control requirements. Although the fetal fraction of the non-identified sample is extremely low (0.51%), its paternity can still be detected by our proposed PTAS methodology through unique molecular identifier tagging. Paternity of the total 313 samples for mid-to-late pregnancy (i.e., more than seven weeks) can be accurately identified. Extensive experiments indicate that our methodology makes a significant breakthrough in the NIPPT theory and will bring substantial benefits to forensic applications.
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Ácidos Nucleicos Livres , Paternidade , Feminino , Criança , Humanos , Gravidez , Polimorfismo de Nucleotídeo Único , Feto , Sequenciamento de Nucleotídeos em Larga Escala/métodos , GenótipoRESUMO
The overall survival rate of gliomas has not significantly improved despite new effective treatments, mainly due to tumor heterogeneity and drug delivery. Here, we perform an integrated clinic-genomic analysis of 1, 477 glioma patients from a Chinese cohort and a TCGA cohort and propose a potential prognostic model for gliomas. We identify that SBS11 and SBS23 mutational signatures are associated with glioma recurrence and indicate worse prognosis only in low-grade type of gliomas and IDH-Mut subtype. We also identify 42 genomic features associated with distinct clinical outcome and successfully used ten of these to develop a prognostic risk model of gliomas. The high-risk glioma patients with shortened survival were characterized by high level of frequent copy number alterations including PTEN, CDKN2A/B deletion, EGFR amplification, less IDH1 or CIC gene mutations, high infiltration levels of immunosuppressive cells and activation of G2M checkpoint and Oxidative phosphorylation oncogenic pathway.
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Nanostructured piezoelectric semiconductors offer unprecedented opportunities for high-performance sensing in numerous catalytic processes of biomedical, pharmaceutical, and agricultural interests, leveraging piezocatalysis that enhances the catalytic efficiency with the strain-induced piezoelectric field. Here, a cost-efficient, high-performance piezo-electrocatalytic sensor for detecting l-ascorbic acid (AA), a critical chemical for many organisms, metabolic processes, and medical treatments, is designed and demonstrated. Zinc oxide (ZnO) nanorods and nanosheets are prepared to characterize and compare their efficacy for the piezo-electrocatalysis of AA. The electrocatalytic efficacy of AA is significantly boosted by the piezoelectric polarization induced in the nanostructured semiconducting ZnO catalysts. The charge transfer between the strained ZnO nanostructures and AA is elucidated to reveal the mechanism for the related piezo-electrocatalytic process. The low-temperature synthesis of high-quality ZnO nanostructures allows low-cost, scalable production, and integration directly into wearable electrocatalytic sensors whose performance can be boosted by otherwise wasted mechanical energy from the working environment, for example, human-generated mechanical signals.
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Although leaf economics spectrum (LES) has been extensively tested with regional and global datasets, the correlation among functional traits of desert plants remains largely unclear. Moreover, examinations on whether and how leaf and root traits are coordinated have yielded mixed results. We investigated variations in leaf and fine-root traits across 48 species in a desert community of northern China to test the hypotheses that (1) the leaf-trait syndrome of plant species in desert shrublands follows the predictions of the global LES, and is paralleled by a similar root-trait syndrome, (2) functional traits related to nutrient contents and resource uptake are tightly coordinated between leaves and fine roots in desert ecosystems where plant growth is limited primarily by dry and nutrient-poor conditions, and (3) traits as well as their relationships vary among functional groups. Our results partially supported the LES theory. Specific leaf area (SLA) was correlated with leaf tissue density, phosphorus content, and carbon-to-nitrogen ratio, but not with leaf nitrogen content. Specific root length (SRL) was not correlated with other fine-root traits, and fine-root traits were largely independent of each other. Therefore, fine-root traits did not mirror the leaf-trait syndrome. Fine-root nitrogen and phosphorus contents, nitrogen-to-phosphorous ratio, and carbon-to-nitrogen ratio all increased with analogous leaf traits, whereas SRL was not correlated with SLA. After phylogenetic effects were considered, nutrient contents and their ratios still displayed stronger coordination between leaves and fine roots than did SRL and SLA. The overall pattern of trait variations and relationships suggested differentiation among functional groups. Our results suggest that despite the absence of a root-trait syndrome, fine-root functions in the studied desert community were probably coordinated with leaf functions with respect to nutrient allocation and use.
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Photocatalytic hydrogen energy production through water splitting paves a promising pathway for alleviating the increasingly severe energy crisis. Seeking affordable, highly active, and stable photocatalysts is crucial to access the technology in a sustainable manner. Herein, a trivalent iron-doped covalent triazine-based framework (CTF-1) was elaborately designed in this study to finely tune the band structure and photocatalytic activity of CTF-1 for H2 production. With optimal doping amount, Fe10 /CTF-1 exhibited a satisfying H2 production activity of 1460â µmol h-1 g-1 , corresponding to 28-fold enhancement compared with pure CTF-1. The Fe3+ doping is responsible for a remarkedly broadened visible-light adsorption range, improved reduction ability and inhibited electron-hole recombination of CTF-1. Specifically, the doped Fe3+ could serve as photocatalytically active center and "electron relay" to accelerate charge separation and transformation. This study offers a feasible strategy to validly design and synthesize CTF-based photocatalytic materials to efficiently utilize solar energy.
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Evapotranspiration (ET) is an important part of water cycle and energy flow in ecosystem. Accurate estimation of ET and its components is critical for understanding the impacts of ecophysiological processes on ecosystem water balance and plant water use strategy. Using the eddy-covariance technique and the micro-lysimeter, we measured ET, evaporation (E), transpiration (T) of the Artemisia ordosica-Hedysarum fruticosum var. mongolicum shrubland in the Mu Us Desert during May 20 to September 15, 2019, quantified the ET components, and analyzed the seasonal characteristics and influencing factors of ET and its components. The results showed that T was the main component of ET in the growing season, with a T/ET of 53.1%. T/ET increased and E/ET decreased as precipitation decreased. The partitioning of evapotranspiration was regulated by precipi-tation. At the seasonal scale, the value of E was positively correlated with soil water content at 10 cm depth (SWC10) and net radiation (Rn), while SWC10 was the main factor influencing E. The value of T increased with the increases of Rn and leaf area index (LAI), and increased first and then decreased with the increases of soil water content at 30 cm layer (SWC30). T was affected by SWC30, Rn and LAI. Moisture was the main influencing factor of ET. The ET/P in the growing season was 109.2% and was 250.5% in May, indicating that the water consumption of ET in early growing season was partly from the precipitation in non-growing season.
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Artemisia , Ecossistema , China , Transpiração Vegetal , Estações do Ano , Solo , ÁguaRESUMO
As a high biologically toxic heavy metal ion, Cr(VI) will cause environmental pollution and endanger human health. Therefore, the development of fast, simple and visible detection methods for Cr(VI) is extremely important to control its harm. Toward this end, we report the establishment of a colorimetric sensing method for Cr(VI) based on single-atom nanozymes for enhanced detection performance. Firstly, we prepared SA-Fe/NG as peroxidase mimetic by anchoring Fe single-atom onto a single-layer of two-dimensional nitrogen-doped graphene. The SA-Fe/NG showed superiorly high oxidation catalytic activity due to its 100% atomic utilization and existing Fe-N-C structure. Furthermore, with 3,3',5,5'-tetramethylbenzidine (TMB) as a colorimetric sensing probe, and 8-hydroxyquinoline (8-HQ) as an inhibitor for the oxidation of TMB, the detection of Cr(VI) was realized through specific interaction between Cr(VI) and 8-HQ, which led to the recovery of oxTMB in blue color. Our established method showed superior sensitivity with a detection limit of 3 nM and a linear range of 30 nM to 3 µM. It also exhibited high selectivity for a series of metal cations, and has been successfully applied to the detection of Cr(VI) in tap water and tuna samples.
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Cromo/análise , Colorimetria , Poluentes Ambientais/análise , Água Potável/análise , Humanos , Peroxidase , Peroxidases , Alimentos MarinhosRESUMO
Development of nontoxic, targetable and potent small interfering RNAs (siRNA) delivery systems remains a predominant challenge for clinical application of siRNA therapy. The nanoparticles of carboxymethyl chitosan (CMC) and labeled fluorescein isothiocyanate (FITC)-chitosan hydrochloride (CHC) were fabricated as carriers for ultrasound-triggered drug delivery to treat colon cancer. The results showed the (FITC-CHC)-CMC nanoparticles could effectively encapsulate anti-ß-catenin siRNA through ionic gelation self-assembly to improve the stability of siRNA. The cumulative release ratio of siRNA from crosslinked (FITC-CHC)-CMC nanoparticles was merely 11.08% in pH 2.2 solution within 120 min, whereas about 70.07% of the loaded siRNA was released within 120 min in pH 5.5 solution after an 8-min ultrasonic treatment. It indicated that the (FITC-CHC)-CMC based pH-sensitive delivery system could fulfill a controlled release of siRNA through responding to external stimulus (ultrasound) under favorable pH condition. Fluorescence microscopy measurements clearly visualized the entry of fluorescently-labeled siRNA into HT-29 cells. Following the transfection of anti-ß-catenin siRNA for 48 h, the ß-catenin protein expression of the colon cancer cells was reduced to about 40.10%, indicating effective reduction of the protein that promotes colon cancer proliferation. Our results demonstrated that the siRNA-(FITC-CHC)-CMC delivery system hold substantial potential for RNAi therapeutical applications in diseased cells.
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Quitosana/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos , Nanopartículas , RNA Interferente Pequeno , Ondas Ultrassônicas , Quitosana/química , Quitosana/farmacologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Células HT29 , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologiaRESUMO
As one of the most endangered species, tiger (Panthera tigris) inbreeding has become an urgent issue to address. Using a microsatellite (short tandem repeat, STR) identification system, paternity testing may be helpful to avoid inbreeding in captive breeding programs. In this study, we developed a genome-based identification system named tiger pedigree identification multiplex system (TPI-plex). By analyzing the entire tiger genome, 139,967 STR loci were identified and 12.76% of these displayed three to six alleles among three re-sequenced individual tiger genomes. A total of 204 candidate STRs were identified and screened with a reference population containing 31 unrelated captive tigers. Of these, 15 loci were chosen for inclusion in the multiplex panel. The mean allele number and mean expected heterozygosity (He) were 7.3333 and 0.7789, respectively. The cumulative probability of exclusion (CPE) and total probability of discrimination power (TDP) reached 0.999999472 and 0.999999999999995, respectively. The results showed that the TPI-plex system can be applied in routine pedigree identification for captive tigers. We also added a sex identification marker named TAMEL into the TPI-plex for sex determination.
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Mercury ion (Hg2+), a bioaccumulating and toxic heavy metal, can cause severe damages to the environment and human health. Therefore, development of high-performance Hg2+ sensors is highly desirable. Herein, we construct a uniform dodecahedral shaped N-doped carbon decorated by single Fe site enzyme (Fe-N-C SAE), which exhibits good performance for Hg2+ detection. The N atom on Fe-N-C SAE can specifically recognize Hg2+ through chelation between Hg2+ and N atom, while the catalytic site on the single-atom enzyme acts as a signal amplifier. The Fe-N-C SAE-functionalized solution-gated graphene transistor exhibits a dramatic improvement in the selectivity and sensitivity of the devices. The sensor can rapidly detect Hg2+ down to 1 nM within 2 s. Besides, a relatively good repeatability and reproducibility for the detection of Hg2+ have also been found in our sensor platform. Our findings expand the application of single-atom catalysts in the field of food safety and environmental monitoring.
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Técnicas Biossensoriais/métodos , Grafite/química , Mercúrio/análise , Água Potável/química , Monitoramento Ambiental , Enzimas , Ferro/química , Nanopartículas Metálicas/química , Modelos Moleculares , Reprodutibilidade dos TestesRESUMO
Visual querying is essential for interactively exploring massive trajectory data. However, the data uncertainty imposes profound challenges to fulfill advanced analytics requirements. On the one hand, many underlying data does not contain accurate geographic coordinates, e.g., positions of a mobile phone only refer to the regions (i.e., mobile cell stations) in which it resides, instead of accurate GPS coordinates. On the other hand, domain experts and general users prefer a natural way, such as using a natural language sentence, to access and analyze massive movement data. In this paper, we propose a visual analytics approach that can extract spatial-temporal constraints from a textual sentence and support an effective query method over uncertain mobile trajectory data. It is built up on encoding massive, spatially uncertain trajectories by the semantic information of the POls and regions covered by them, and then storing the trajectory documents in text database with an effective indexing scheme. The visual interface facilitates query condition specification, situation-aware visualization, and semantic exploration of large trajectory data. Usage scenarios on real-world human mobility datasets demonstrate the effectiveness of our approach.
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Gráficos por Computador , Movimento/fisiologia , Processamento de Linguagem Natural , Algoritmos , Bases de Dados Factuais , Humanos , Semântica , Incerteza , Interface Usuário-ComputadorRESUMO
The feasibility of using celery cellulose hydrogels as carriers was explored for controlled release of short-chain fatty acids (SCFAs) triggered by ultrasound. The hydrogels were prepared with the phase inversion method and further characterized using FT-IR, SEM and XRD techniques. At the optimal cellulose concentration (8.33 and 6.25â¯mg/mL), the hydrogels (F4 and F5) exhibited the swelling ratio of 185%, and Young's modulus of the F4 and F5 was lower than that of others. The hydrogels were loaded with SCFAs owing to its hydrophilicity and swelling properties, and the maximum loading capacity of SCFAs achieved nearly 80%. Interestingly, the loaded SCFAs within hydrogel carrier could be readily released if an ultrasound trigger is exerted. Our results indicate that the ultrasound-triggered strategy for the SCFAs delivery system could provide a promising basis to achieve on-demand, reproducible, repeated, and tunable dosing of bioactive molecules.
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Apium/metabolismo , Celulose/química , Ácidos Graxos Voláteis/química , Hidrogéis/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Módulo de Elasticidade , Ácidos Graxos Voláteis/metabolismo , SonicaçãoRESUMO
A material with reversible temperature change capability under an external electric field, known as the electrocaloric effect (ECE), has long been considered as a promising solid-state cooling solution. However, electrocaloric (EC) performance of EC materials generally is not sufficiently high for real cooling applications. As a result, exploring EC materials with high performance is of great interest and importance. Here, we report on the ECE of ferroelectric materials with van der Waals layered structure (CuInP2S6 or CIPS in this work in particular). Over 60% polarization charge change is observed within a temperature change of only 10 K at Curie temperature. Large adiabatic temperature change (|ΔT|) of 3.3 K and isothermal entropy change (|ΔS|) of 5.8 J kg-1 K-1 at |ΔE| = 142.0 kV cm-1 and at 315 K (above and near room temperature) are achieved, with a large EC strength (|ΔT|/|ΔE|) of 29.5 mK cm kV-1. The ECE of CIPS is also investigated theoretically by numerical simulation, and a further EC performance projection is provided.
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Recent advances achieved in triboelectric nanogenerators (TENG) focus on boosting power generation and conversion efficiency. Nevertheless, obstacles concerning economical and biocompatible utilization of TENGs continue to prevail. Being an abundant natural biopolymer from marine crustacean shells, chitosan enables exciting opportunities for low-cost, biodegradable TENG applications in related fields. Here, the development of biodegradable and flexible TENGs based on chitosan is presented for the first time. The physical and chemical properties of the chitosan nanocomposites are systematically studied and engineered for optimized triboelectric power generation, transforming the otherwise wasted natural materials into functional energy devices. The feasibility of laser processing of constituent materials is further explored for the first time for engineering the TENG performance. The laser treatment of biopolymer films offers a potentially promising scheme for surface engineering in polymer-based TENGs. The chitosan-based TENGs present efficient energy conversion performance and tunable biodegradation rate. Such a new class of TENGs derived from natural biomaterials may pave the way toward the economically viable and ecologically friendly production of flexible TENGs for self-powered nanosystems in biomedical and environmental applications.
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Ongoing efforts in triboelectric nanogenerators (TENGs) focus on enhancing power generation, but obstacles concerning the economical and cost-effective production of TENGs continue to prevail. Micro-/nanostructure engineering of polymer surfaces has been dominantly utilized for boosting the contact triboelectrification, with deposited metal electrodes for collecting the scavenged energy. Nevertheless, this state-of-the-art approach is limited by the vague potential for producing 3D hierarchical surface structures with conformable coverage of high-quality metal. Laser-shock imprinting (LSI) is emerging as a potentially scalable approach for directly surface patterning of a wide range of metals with 3D nanoscale structures by design, benefiting from the ultrahigh-strain-rate forming process. Here, a TENG device is demonstrated with LSI-processed biomimetic hierarchically structured metal electrodes for efficient harvesting of water-drop energy in the environment. Mimicking and transferring hierarchical microstructures from natural templates, such as leaves, into these water-TENG devices is effective regarding repelling water drops from the device surface, since surface hydrophobicity from these biomicrostructures maximizes the TENG output. Among various leaves' microstructures, hierarchical microstructures from dried bamboo leaves are preferable regarding maximizing power output, which is attributed to their unique structures, containing both dense nanostructures and microscale features, compared with other types of leaves. Also, the triboelectric output is significantly improved by closely mimicking the hydrophobic nature of the leaves in the LSI-processed metal surface after functionalizing it with low-surface-energy self-assembled-monolayers. The approach opens doors to new manufacturable TENG technologies for economically feasible and ecologically friendly production of functional devices with directly patterned 3D biomimic metallic surfaces in energy, electronics, and sensor applications.