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Cellulose nanofiber (CNF) possesses excellent intrinsic properties, and many CNF-based high-performance structural and functional materials have been developed recently. However, the coordination of the mechanical properties and functionality is still a considerable challenge. Here, a CNF-based structural material is developed by a bioinspired gradient structure design using hollow magnetite nanoparticles and the phosphorylation-modified CNF as building blocks, which simultaneously achieves a superior mechanical performance and electromagnetic wave absorption (EMA) ability. Benefiting from the gradient design, the flexural strength of the structural material reached â¼205 MPa. Meanwhile, gradient design improves impedance matching, contributing to the high EMA ability (-59.5 dB) and wide effective absorption width (5.20 GHz). Besides, a low coefficient of thermal expansion and stable storage modulus was demonstrated as the temperature changes. The excellent mechanical, thermal, and EMA performance exhibited great potential for application in stealth equipment and electromagnetic interference protecting electronic packaging materials.
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Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.
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Actinas , Antioxidantes , Benzofuranos , Depsídeos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Actinas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Vimentina/metabolismo , Estresse Oxidativo , Metionina , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Proteínas do Citoesqueleto/metabolismo , Miosinas/metabolismo , Miosinas/farmacologiaRESUMO
Yeast, which plays a pivotal role in the brewing, food, and medical industries, exhibits a close relationship with human beings. In this study, we isolated and purified 60 yeast strains from the natural fermentation broth of Sidamo coffee beans to screen for indigenous beneficial yeasts. Among them, 25 strains were obtained through morphological characterization on nutritional agar medium from Wallerstein Laboratory (WL), with molecular biology identifying Saccharomyces cerevisiae strain YBB-47 and the remaining 24 yeast strains identified as Pichia kudriavzevii. We investigated the fermentation performance, alcohol tolerance, SO2 tolerance, pH tolerance, sugar tolerance, temperature tolerance, ester production capacity, ethanol production capacity, H2S production capacity, and other brewing characteristics of YBB-33 and YBB-47. The results demonstrated that both strains could tolerate up to 3% alcohol by volume at a high sucrose mass concentration (400 g/L) under elevated temperature conditions (40 â), while also exhibiting a remarkable ability to withstand an SO2 mass concentration of 300 g/L at pH 3.2. Moreover, S. cerevisiae YBB-47 displayed a rapid gas production rate and strong ethanol productivity. whereas P. kudriavzevii YBB-33 exhibited excellent alcohol tolerance. Furthermore, this systematic classification and characterization of coffee bean yeast strains from the Sidamo region can potentially uncover additional yeasts that offer high-quality resources for industrial-scale coffee bean production.
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Etanol , Fermentação , Pichia , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/isolamento & purificação , Pichia/metabolismo , Pichia/isolamento & purificação , Pichia/genética , Pichia/classificação , Etanol/metabolismo , Concentração de Íons de Hidrogênio , Café/microbiologia , Coffea/microbiologia , Temperatura , Sementes/microbiologia , Sulfeto de Hidrogênio/metabolismoRESUMO
BACKGROUND AND AIMS: The International AIH Pathology Group (IAIH-PG) put forward the new histological criteria of autoimmune hepatitis (AIH) in 2022, which have not undergone adequate verification. In this study, we verified the applicability of the new histological criteria in the population of Chinese patients with chronic liver disease, comparing it with the simplified criteria. METHODS: The gold standard for diagnosis in all patients was based on histological findings, combined with clinical manifestations and laboratory tests and determined after a follow-up period of at least 3 years. A total of 640 patients with various chronic liver diseases from multiple centres underwent scoring using the new histological criteria and the simplified criteria, comparing their diagnostic performance. RESULTS: In this study, the new histological criteria showed a sensitivity of 73.6% and 100% for likely and possible AIH, with specificities of 100% and 69.0% respectively. The coincidence rates of possible AIH for the new histological criteria, simplified histological criteria and simplified score were 81.7%, 72.8% and 69.7% respectively. For likely AIH, the rates were 89.2%, 75.9% and 65.6% respectively. Based on the new histological criteria, all patients with AIH were correctly diagnosed. Specifically, 73.6% were diagnosed with likely AIH and 26.4% were possible AIH. Additionally, the simplified histological criteria achieved a diagnosis rate of 98.6% for AIH, while the simplified score could only diagnose 53.8% of AIH. CONCLUSIONS: Compared with the simplified score and simplified histological criteria, the sensitivity and specificity of the new histological criteria for AIH were significantly improved. The results indicate that the new histological criteria exhibit high sensitivity and specificity for diagnosing AIH in China.
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Consenso , Hepatite Autoimune , Sensibilidade e Especificidade , Humanos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/patologia , China , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Doença Crônica , Idoso , Fígado/patologia , Hepatopatias/diagnóstico , Hepatopatias/patologia , Adulto JovemRESUMO
PCDD/Fs are dioxins produced by waste incineration and pose risks to human health. We aimed to detail the health risks of airborne and soil PCDD/Fs near a municipal solid-waste incinerator (MSWI) for the surrounding population and develop a new model that improves upon existing methods. Thus, we conducted field sampling and then investigated a MSWI in the Pearl River Delta (2016-2018). Our results showed that the carcinogenic and non-carcinogenic risk values of PCDD/Fs exposed to residents in nearby areas were acceptable, with hazard index (HI) values lower than 1.0 and a total carcinogenic risk lower than 1.0E-6. Notably, the results raised concerns regarding higher non-carcinogenic risks in children than in adults. Comparative analysis of the frequency accumulation diagram, accumulated probability risk, and the absolute value of error (δ) between the 95% confidence interval (CI) and the 90% CI of the Monte Carlo stochastic simulation-triangular fuzzy number (MCSS-TFN) and the MCSS model, respectively, demonstrated that the MCSS-TFN exhibited less uncertainty than the MCSS model, regardless of the health risk value of PCDD/Fs in ambient air or in soil. This observation underscores the superiority of the MCSS-TFN model over other models in assessing the health risks associated with PCDD/Fs in situations with limited data. Our new method overcomes the limited dataset size and high uncertainty in assessing the health risks of dioxin substances, providing a more comprehensive understanding of their associated health risks than MCSS models.
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Poluentes Atmosféricos , Dioxinas , Dibenzodioxinas Policloradas , Adulto , Criança , Humanos , Resíduos Sólidos , Monitoramento Ambiental/métodos , Dibenzodioxinas Policloradas/toxicidade , Dibenzodioxinas Policloradas/análise , Dibenzofuranos , Poluentes Atmosféricos/análise , Incineração , Dioxinas/toxicidade , Medição de Risco , Dibenzofuranos Policlorados/análise , SoloRESUMO
Constructing structural materials from sustainable raw materials is considered an efficient way to reduce the potential threat posed by plastics. Nevertheless, challenges remain regarding combining excellent mechanical and thermal properties, especially the balance of strength and toughness. Here, we report a 3D nanofiber network interfacial design strategy to strengthen and toughen all-natural structural materials simultaneously. The introduced protonated chitosan at the interface between the surface oxidized 3D nanonetwork of bacterial cellulose forms the interfacial interlocking structure of nanonetworks, achieving a robust physical connection and providing enough physical contact sites for chemical crosslinking. The obtained sustainable structural material successfully integrates excellent mechanical and thermal properties on the nanoscale of cellulose nanofibers, such as light weight, high strength, and superior thermal expansion coefficient. The relationship between structural design and comprehensive mechanical property improvement is analyzed in detail, providing a universal perspective to design sustainable high-performance structural materials from nanoscale building blocks.
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Bacterial lipopolysaccharide (LPS) is a toxic stimulant to macrophage inflammation. Inflammation intersects cell metabolism and often directs host immunopathogenesis stress. We aim here at pharmacological discovering of formononetin (FMN) action, to which anti-inflammatory signaling spans across immune membrane receptors and second messenger metabolites. In ANA-1 macrophage stimulated by LPS, and simultaneous treatment with FMN, results show the Toll-like receptor 4 (TLR4) and estrogen receptor (ER) signals, in concert with reactive oxygen species (ROS) and cyclic adenosine monophosphate (cAMP), respectively. LPS stimulates inactivation of the ROS-dependent nuclear factor erythroid 2-related factor 2 (Nrf2) by upregulating TLR4, but it does not affect cAMP. However, FMN treatment not only activates Nrf2 signaling by TLR4 inhibition, but also it activates cAMP-dependent protein kinase activities by upregulating ER. The cAMP activity gives rise to phosphorylation (p-) of protein kinase A, liver kinase B1 and 5'-AMP activated protein kinase (AMPK). Moreover, bidirectional signal crosstalk is amplified between p-AMPK and ROS, as FMN combinational validation with AMPK activator/inhibitor/target small-interfering RNA or ROS scavenger. The signal crosstalk is well positioned serving as the 'plug-in' knot for rather long signaling axis, and the immune-to-metabolic circuit via ER/TLR4 signal transduction. Collectively, convergence of the FMN-activated signals drives significant reduction of cyclooxygenase-2, interleukin-6 and NLR family pyrin domain-containing protein 3, in LPS-stimulated cell. Although anti-inflammatory signaling is specifically related to the immune-type macrophage, the p-AMPK antagonizing effect arises from FMN combination with ROS scavenger H-bond donors. Information of our work assists in predictive traits against macrophage inflammatory challenges, using phytoestrogen discoveries.
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Proteínas Quinases Ativadas por AMP , Receptor 4 Toll-Like , Humanos , Espécies Reativas de Oxigênio/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Lipopolissacarídeos/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Macrófagos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Anti-Inflamatórios/farmacologiaRESUMO
Photodynamic therapy (PDT) uses a combination of photosensitizers (PSs), light sources, and reactive oxygen species (ROS) to damage only the desired target and keep normal tissues from being hurt. The dark cytotoxicity (chemotoxicity) of PSs, leading to whole-body damage in the absence of irradiation, is a major limiting factor in PDT. How to simultaneously increase ROS generation and decrease dark cytotoxicity is an essential challenge that must be resolved in PS research. In this study, a series of homoligand polypyridyl ruthenium complexes (HPRCs) containing three singlet oxygen (1O2)-generating ligands (L) in a single molecule ([Ru(L)3]2+) have been constructed. Compared to the heteroligand complexes [Ru(bpy)2(L)]2+ where bpy is 2,2'-bipyridine, the 1O2 quantum yield under infrared two-photon irradiation and the DNA photocleavage effect of the HPRCs are significantly enhanced with two more ligands L. The intraligand triplet excited states transition played an important role in the activation of oxygen. The HPRCs target the mitochondria but not the nuclei, generating 1O2 intracellularly under irradiation of visible or infrared light. Ru1 exhibits high phototoxicity and low dark cytotoxicity toward human malignant melanoma cells in vitro. Moreover, HPRCs have minimal cytotoxicity to human normal liver cells, suggesting their potential as antitumor PDT reagents with more security. This study may provide inspiration for the structural design of potent PS for PDT.
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Complexos de Coordenação , Fotoquimioterapia , Rutênio , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Rutênio/farmacologia , Rutênio/química , Espécies Reativas de Oxigênio , Complexos de Coordenação/farmacologia , Complexos de Coordenação/químicaRESUMO
BACKGROUND: Complications and diagnostic efficiency for liver biopsy are main concerns for clinicians. This study aimed to assess the safety and efficacy of transjugular liver biopsy (TJLB) compared with percutaneous liver biopsy (PLB) when patients had equal level of liver function and number of passes, using propensity score matching (PSM). METHODS: The clinical and pathological data of patients who received TJLB or PLB between January 2012 and October 2022 were collected. Matching factors included age, gender, cirrhosis, portal hypertension, liver function, creatinine, number of passes, hemodialysis, history of anti-coagulation and anti-platelet, and comorbidities. Coagulation indexes were not considered as matching factors due to different indications of the two techniques. RESULTS: 2711 PLBs and 30 TJLBs were evaluated. By PSM, 75 patients (50 PLBs, 25 TJLBs) were matched. The complication rates for TJLB and PLB were 4.0% (1/25) and 10.0% (5/50) (P > 0.05). Two PLBs had hepatic hemorrhage, one of which required only close monitoring (Grade 1) and the other needed hemostasis and rehydration therapy (Grade 2). The other 3 cases presented with mild abdominal pain (Grade 1). And only one TJLB presented with mild pain. The median number of complete portal tracts were 6.0 and 10.0 for TJLBs and PLBs (P < 0.05). Moreover, the median length of sample for TJLBs and PLBs were 10.0 and 16.5 mm (P < 0.05). The diagnostic efficiency of hepatopathy of unknown etiology of TJLB versus PLB groups before and after matching were 96.4% vs. 94.1% and 95.7% vs. 93.2%, respectively (P > 0.05). CONCLUSION: TJLB is an effective invasive diagnostic procedure that expands indications for liver biopsy with reliable diagnostic quality.
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Hipertensão Portal , Hepatopatias , Humanos , Veias Jugulares/patologia , Fígado/patologia , Biópsia/efeitos adversos , Biópsia/métodos , Hepatopatias/patologia , Hipertensão Portal/etiologia , Hipertensão Portal/patologia , Dor Abdominal/etiologiaRESUMO
MnTBAP is a new synthetic antioxidant that has been used for the cryopreservation of sperm. However, the exact mechanism of its cryoprotection at the molecular level is largely unknown. Therefore, in this study, normal human semen samples were selected and MnTBAP (0, 5, 10, 20, 40 µM) was added to sperm freezing medium to assess changes in kinetics parameters, apoptosis, reactive oxygen species (ROS), and DNA fragmentation index (DFI) after sperm ultra-rapid freezing. The tandem masstagging (TMT) proteomics technique was used to further investigate the changes in proteins after sperm ultra-rapid freezing. The kinetic parameters of sperm after ultra-rapid freezing and thawing were significantly reduced and apoptosis, ROS production and DFI were significantly increased. The addition of 40 µM MnTBAP improved the kinetic parameters, while it reduced apoptosis, ROS production, and DFI of sperm after ultra-rapid freezing and thawing (P < 0.05). Compared with the fresh semen, 1978 differential proteins were identified in the frozen-thawed sperm without MnTBAP and 1888 differential proteins were identified in the frozen-thawed sperm with MnTBAP (40 µM) added. The proteins affected during ultra-rapid freezing were mainly related to sperm metabolism, flagellar structure motility, apoptosis, intracellular signaling, capacitation and fertilization, while the addition of MnTBAP reduced the alterations of these proteins.
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Preservação do Sêmen , Sêmen , Masculino , Humanos , Congelamento , Sêmen/metabolismo , Criopreservação/métodos , Espécies Reativas de Oxigênio/metabolismo , Proteômica , Preservação do Sêmen/métodos , Espermatozoides , Motilidade dos EspermatozoidesRESUMO
The oriented pore structure of wood endows it with a variety of outstanding properties, among which the low thermal conductivity has attracted researchers to develop wood-like aerogels as excellent thermal insulation materials. However, the increasing demands of environmental protection have put forward new and strict requirements for the sustainability of aerogels. Here, we report an all-natural wood-inspired aerogel consisting of all-natural ingredients and develop a method to activate the surface-inert wood particles to construct the aerogel. The obtained wood-inspired aerogel has channel structure similar to that of natural wood, endowing it with superior thermal insulation properties to most existing commercial sponges. In addition, remarkable fire retardancy and complete biodegradability are integrated. With the above outstanding performances, this sustainable wood-inspired aerogel will be an ideal substitute for the existing commercial thermal insulation materials.
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Exosomes are well-known key mediators of intercellular communication and contribute to various physiological and pathological processes. Their biogenesis involves four key steps, including cargo sorting, MVB formation and maturation, transport of MVBs, and MVB fusion with the plasma membrane. Each process is modulated through the competition or coordination of multiple mechanisms, whereby diverse repertoires of molecular cargos are sorted into distinct subpopulations of exosomes, resulting in the high heterogeneity of exosomes. Intriguingly, cancer cells exploit various strategies, such as aberrant gene expression, posttranslational modifications, and altered signaling pathways, to regulate the biogenesis, composition, and eventually functions of exosomes to promote cancer progression. Therefore, exosome biogenesis-targeted therapy is being actively explored. In this review, we systematically summarize recent progress in understanding the machinery of exosome biogenesis and how it is regulated in the context of cancer. In particular, we highlight pharmacological targeting of exosome biogenesis as a promising cancer therapeutic strategy.
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Exossomos , Neoplasias , Humanos , Exossomos/metabolismo , Corpos Multivesiculares/metabolismo , Neoplasias/metabolismo , Comunicação Celular , Membrana Celular/metabolismoRESUMO
BACKGROUND: Aberrant cytokeratin 7 expression by hepatocytes (CK7+Hs) is the hallmark characteristic of cholestasis diseases, especially in ductopenia diseases such as primary biliary cholangitis (PBC). This study attempted to evaluate the differences and relationships between the clinical and histological features of aberrant cytokeratin 7 (CK7) expression by hepatocytes in PBC patients. METHODS: The clinicopathological data of patients diagnosed with PBC at the Second Hospital of Nanjing between January 2016 and September 2018 were analysed with SPSS 20.0. RESULTS: Eighty-nine PBC patients who underwent liver biopsy were enrolled in this study, and 15, 29 and 45 patients had aberrant CK7 expression by hepatocytes (CK7+Hs (2 +), CK7+Hs (1 +), and CK7-Hs, respectively). There were significant differences in TB, DB, ALP, TA, IgM, interface activity, and ductopenia grade between patients with CK7-Hs and CK7+Hs (2 +) (P < 0.05). The ductopenia grade was also significantly different between patients with CK7+Hs (2 +) and CK7+Hs (1 +) according to sex (P < 0.05). Upon merging the data of CK7+Hs (2 +) and CK7+Hs (1 +) into CK7+Hs, we found significant differences in AMA, AMA-M2, anti-gp210, TB, DB, ALP, TA, IgM, fibrosis, and ductopenia grade between CK7+Hs and CK7-Hs (P < 0.05). The odds ratios (ORs) (and 95% confidence intervals (CIs)) of CK7+Hs according to anti-gp210, ductopenia grade, and interface activity were 6.413 (95% CI 1.363-30.162), 4.145 (95% CI 1.898-9.052) and 3.247 (95% CI 1.556-6.775), respectively (P < 0.05). Spearman's rank correlation according to interface activity and ductopenia grade in patients with CK7+Hs (2 + , 1 + , 0) was r = 0.359 (P = 0.001) and r = 0.396 (P < 0.001), respectively. CONCLUSION: CK7+Hs serves as a cholestasis index of PBC and are associated with the ductopenia grade and interface activity. Aberrant cytokeratin 7 expression by hepatocytes can predict the ductopenia grade in primary biliary cholangitis.
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Colangite , Colestase , Cirrose Hepática Biliar , Humanos , Queratina-7/metabolismo , Cirrose Hepática Biliar/diagnóstico , Hepatócitos/metabolismo , Colestase/patologia , Imunoglobulina M , Colangite/patologiaRESUMO
The aim was to investigate the influences of different sperm sources on clinical outcome and neonatal outcome of patients with intracytoplasmic sperm injection. We retrospectively analysed patients who underwent intracytoplasmic sperm injection in our reproductive centre from 2011 to 2020. We screened data on assisted reproductive outcomes from four groups of sources: testicular sperm, epididymal sperm, ejaculated sperm and donor sperm for analysis and divided the non-ejaculated group from the ejaculated group to explore their impact on clinical outcomes and neonatal outcomes. A total of 2139 cycles were involved in this study. There were significant differences in fertilisation rate (77.0% vs. 73.6%, p < .001), cleavage rate (97.4% vs. 94.4%, p < .001) and high-quality embryo rate (52.8% vs. 49.9%, p < .001) between the ejaculated and non-ejaculated sperm groups. There were no significant differences amongst the four groups in biochemical pregnancy rate, clinical pregnancy rate, abortion rate, live birth rate, male-female ratio and single-twin ratio. Different sperm sources did not affect the length, weight or physical defects of newborns amongst the groups. Sperm source did not affect pregnancy and neonatal outcomes of intracytoplasmic sperm injection in general.
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Sêmen , Injeções de Esperma Intracitoplásmicas , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Recuperação Espermática/efeitos adversos , EspermatozoidesRESUMO
Ubiquitous petrochemical-based plastics pose a potential threat to ecosystems. In response, bioderived and degradable polymeric materials are being developed, but their mechanical and thermal properties cannot compete with those of existing petrochemical-based plastics, especially those used as structural materials. Herein, we report a biodegradable plant cellulose nanofiber (CNF)-derived polymeric structural material with high-density reversible interaction networks between nanofibers, exhibiting mechanical and thermal properties better than those of existing petrochemical-based plastics. This all-green material has substantially improved flexural strength (â¼300 MPa) and modulus (â¼16 GPa) compared with those of existing petrochemical-based plastics. Its average thermal expansion coefficient is only 7 × 10-6 K-1, which is more than 10 times lower than those of petrochemical-based plastics, indicating its dimension is almost unchanged when heated, and thus, it has a thermal dimensional stability that is better than those of plastics. As a fully bioderived and degradable material, the all-green material offers a more sustainable high-performance alternative to petrochemical-based plastics.
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Celulose , Nanofibras , Celulose/química , Ecossistema , Nanofibras/química , Plásticos , PolímerosRESUMO
Electromagnetic interference (EMI) shielding materials with excellent EMI shielding efficiency (SE), lightweight property, and superb mechanical performance are vitally important for modern society, but it is still a challenge to realize these performances simultaneously on one material. Here, we report a sustainable bioinspired double-network structural material with excellent specific strength (146 MPa g-1 cm3) and remarkable EMI SE (100 dB) from cellulose nanofiber (CNF) and carbon nanotubes (CNTs), which demonstrates remarkable and outstanding performance to both typical metal materials and reported polymer composites. In particular, the bioinspired double-network structure design simultaneously achieves an extremely high electrical conductivity and mechanical strength, which makes it a lightweight, high shielding efficiency, and sustainable structural material for real-life electromagnetic wave shielding applications.
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Hydrogel materials with high water content and good biocompatibility are drawing more and more attention now, especially for biomedical use. However, it still remains a challenge to construct hydrogel fibers with enough strength and toughness for practical applications. Herein, we report a bio-inspired lotus-fiber-mimetic spiral structure hydrogel bacterial cellulose fiber with high strength, high toughness, high stretchability, and energy dissipation, named biomimetic hydrogel fiber (BHF). The spiral-like structure endows BHF with excellent stretchability through plastic deformation and local failure, assisted by the breaking-reforming nature of the hydrogen bonding network among cellulose nanofibers. With the high strength, high stretchability, high energy dissipation, high hydrophilicity, porous structure, and excellent biocompatibility, BHF is a promising hydrogel fiber for biomedicine. The outstanding stretchability and energy dissipation of BHF allow it to absorb energy from the tissue deformation around a wound and effectively protect the wound from rupture, which makes BHF an ideal surgical suture.
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Lotus , Nanofibras , Celulose , Hidrogéis , PorosidadeRESUMO
As the key intermediate phase of crystalline calcium carbonate biominerals, amorphous calcium carbonate (ACC) remains mysterious in its structures because of its long-range disorder and instability. We herein report the synthesis of ACC nanospheres in a water-deficient organic solvent system. The obtained ACC nanospheres are very stable under dry conditions. Cryo-TEM reveals that each nanospheres consists of smaller nanosized clusters. We further demonstrate that these clusters can precipitate on other substrates to form an ultrathin ACC coating, which should be an ACC cluster monolayer. The results demonstrate that the presence of small ACC clusters as the subunits of larger aggregates is inherent to ACC synthesized in water-alcohol system but not induced by polymer additives.
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Nanosferas , Água , Água/química , Nanosferas/química , Carbonato de Cálcio/química , SolventesRESUMO
Holey graphyne (HGY), a novel two-dementional 2D single-crystalline carbon allotrope, was recently synthesized by Castro-Stephens coupling reaction. The naturally existing uniform periodic holes in the 2D carbon-carbon network demonstrate its promising potential in the energy storage. Herein, we conducted density functional theory (DFT) calculation to predict the hydrogen storage capacity of HGY sheet. It is found the Li-decorated single-layer HGY can serve as a promising candidate for hydrogen storage. Our DFT calculations demonstrate that Li atoms can bind strongly to the HGY sheet without the formation of Li clusters, and each Li atom can anchor four H2 molecules with the average adsorption energy about ï0.22 eV/H2. The largest hydrogen storage capacity of the doped HGY sheet can reach as high as 12.8 wt%, largely surpassing the target of the U. S. DOE (9 wt%), showing the Li/HGY complex is an ideal hydrogen storage material at ambient conditions. In addition, we investigate the polarization mechanism of the storage media and find that the polarization is originated from both the electric field induced by the ionic Li decorated on the HGY and the weak polarized hydrogen molecules dominated the H2 adsorption process.
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Applying organic fertilizers has been well documented to facilitate the dissemination of antibiotic resistance genes (ARGs) in soil ecosystems. However, the role of soil fauna in this process has been seldom addressed, which hampers our ability to predict the fate of and to manage the spread of ARGs. Here, using high-throughput quantitative polymerase chain reaction (HT-qPCR), we examined the effect of long-term (5-, 8-, and 10-year) fertilization treatments (control, inorganic fertilizers, and mixed fertilizers) on the transfer of ARGs between soil, nematodes, and earthworms. We found distinct fates for ARGs in the nematodes and earthworms, with the former having higher enriched levels of ARGs than the latter. Fertilization impacted the number and abundance of ARGs in soil, and fertilization duration altered the composition of ARGs. Shared ARGs among soil, nematodes, and earthworm guts supported by a fast expectation-maximization microbial source tracking analysis demonstrated the trophic transfer potential of ARGs through this short soil food chain. The transfer of ARGs was reduced by fertilization duration, which was mainly ascribed to the reduction of ARGs in the earthworm gut microbiota. This study identified the transfer of ARGs in the soil-nematode-earthworm food chain as a potential mechanism for a wider dissemination of ARGs in the soil ecosystem.