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Water-related issues in transboundary basins are generally complicated by the challenges of climate change, the historical evolution of the basin characteristics, and the different interests of the riparian countries. Therefore, dealing with water-sharing and water cooperation problems among basin countries needs to be based on multi-factor system analysis in the context of regional water, energy, food (land) resources, and ecosystems. In the present study, the Aral Sea basin in Central Asia, where transboundary water problems are extremely prominent and complex, was selected as the research area. Firstly, the characteristics of the water-energy-food-ecosystem nexus of the Aral Sea basin are analyzed. Then, based on the game theory, a multi-objective game model is constructed, and the multi-objective evolutionary game process and evolutionary stable strategies (ESSs) of both the upstream and downstream countries are explored. Finally, the evolutionary stable strategy under the intervention of the basin commission is simulated. The results show that there are obvious reciprocal feedbacks among water, land, energy, and ecosystem in the Aral Sea basin, and the uneven distribution of natural resources, fragile ecosystems, and conflicting demands of multiple actors lead to the unstable evolution of the nexus. Driven by the maximization of upstream and downstream countries' respective interests, the optimal stabilization strategy of the system cannot be realized. Whereas, the introduction of the basin commission intervention and its restraint mechanism is conducive to promoting cooperation and maximizing the overall benefits of the basin. The incentives and penalties of the basin commission have significant effects on whether the system can reach Pareto optimality, and higher incentive coefficient and penalty coefficient help the system converge to the ideal state more quickly. The evolution of the water-energy-food-ecosystem nexus based on the perspective of the whole basin can provide theoretical support for dealing with the transboundary water conflicts, and the cooperation strategy aiming at maximizing the overall benefits of the basin can provide decision-making basis for promoting transboundary water cooperation and synergistic development of the water-energy-food-ecosystem nexus.
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Ecossistema , Água , Abastecimento de Água , Poluição da Água , ÁsiaRESUMO
At present, the main raw material for producing graphene is graphite ore. However, researchers actively seek alternative resources due to their high cost and environmental problems. Biomass waste has attracted much attention due to its carbon-rich structure and renewability, emerging as a potential raw material for graphene production to be used in sports equipment. However, further progress is required on the quality of graphene produced from waste biomass. This paper, therefore, summarizes the properties, structures, and production processes of graphene and its derivatives, as well as the inherent advantages of biomass waste-derived graphene. Finally, this paper reviews graphene's importance and application prospects in sports since this wonder material has made sports equipment available with high-strength and lightweight quality. Moreover, its outstanding thermal and electrical conductivity is exploited to prepare wearable sensors to collect more accurate sports data, thus helping to improve athletes' training levels and competitive performance. Although the large-scale production of biomass waste-derived graphene has yet to be realized, it is expected that its application will expand to various other fields due to the associated low cost and environmental friendliness of the preparation technique.
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Biomassa , Grafite , Equipamentos Esportivos , Humanos , Condutividade Elétrica , Grafite/química , Esportes , Equipamentos Esportivos/economia , Gerenciamento de Resíduos/economiaRESUMO
Nonsmall cell lung cancer (NSCLC) has been a fatal and refractory disease worldwide. Novel therapeutic developments based on fundamental investigations of anticancer mechanisms underlie substantial foundations to win the fight against cancer diseases. In this study, we isolated a natural product fusaricide (FCD) from an endophytic fungus of Lycium barbarum, identified as Epicoccum sp. For the first time, we discovered that FCD potently inhibited proliferation in a variety of human NSCLC cell lines, with relatively less toxicity to normal cells. Our study exhibited that FCD induced apoptosis, caused DNA damage and cell cycle arrest in G0/G1 phase, and activated caspase-3 as well as other apoptosis-related factors in human NSCLC NCI-H460 cells. FCD was proven to be an iron chelator that actively decreased levels of cellular labile iron pool in NCI-H460 cells in our study. FeCl3 supplement reversed FCD-induced apoptosis. The upregulation of transferrin receptor 1 (TfR1) and downregulation of ferritin heavy chain (FTH) expression were observed after FCD treatment. In summary, our study highlighted the potential anticancer effects of FCD against human NSCLCs and demonstrated that the FCD-mediated apoptosis depended on binding to intracellular iron.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzopiranos/farmacologia , Caspase 3/metabolismo , Quelantes de Ferro/farmacologia , Piridonas/farmacologia , Antígenos CD/metabolismo , Apoferritinas/metabolismo , Ascomicetos/química , Carcinoma Pulmonar de Células não Pequenas , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , China , Endófitos/química , Humanos , Neoplasias Pulmonares , Lycium/microbiologia , Estrutura Molecular , Receptores da Transferrina/metabolismoRESUMO
BACKGROUND: Facial angiofibromas may be present since early childhood in individuals with tuberous sclerosis complex (TSC), causing substantial cosmetic disfigurement. Current therapies are partially effective, but they are uncomfortable, produce scarring, and are especially expensive. OBJECTIVE: The aim of the present study was to evaluate the efficacy of oral everolimus for TSC-associated angiofibromas. METHODS: This retrospective study included TSC patients being treated with oral everolimus for subependymal giant cell astrocytomas (SEGAs) and angiomyolipomas (AMLs). We recorded the changes in facial angiofibromas. Changes in the Angiofibroma Grading Scale (AGS) indicators were recorded according to erythema, average lesion size, lesion density, and percent involvement on the forehead, nose, cheeks, and chin. The scores were recorded before and after the administration of oral everolimus. RESULTS: Twenty-one patients being treated with oral everolimus were enrolled in this study. The mean age was 20.5 years (range 11-44 years, 4 males, and 17 females). The mean dose of oral everolimus was 3.6 mg/day. Clinically meaningful and statistically significant improvement was observed in erythema (p = 0.001), average lesion size (p < 0.001), lesion density (p < 0.001), and percent involvement (p < 0.001). Changes in the AGS findings were statistically significant on the forehead (p = 0.001), nose (p < 0.001) cheeks (p < 0.001), and chin (p = 0.004). CONCLUSION: Everolimus shows evident improvement and is approved for TSC-associated SEGAs and AMLs. The current study demonstrated the efficacy of oral everolimus in reducing facial angiofibromas, showing the parallel benefits of the treatment protocol for TSC.
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Angiofibroma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Everolimo/uso terapêutico , Neoplasias Faciais/tratamento farmacológico , Esclerose Tuberosa/complicações , Adolescente , Adulto , Angiofibroma/complicações , Angiofibroma/patologia , Angiomiolipoma/complicações , Angiomiolipoma/tratamento farmacológico , Astrocitoma/complicações , Astrocitoma/tratamento farmacológico , Criança , Neoplasias Faciais/complicações , Neoplasias Faciais/patologia , Feminino , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/tratamento farmacológico , Masculino , Estudos Retrospectivos , Esclerose Tuberosa/patologia , Esclerose Tuberosa/terapia , Adulto JovemRESUMO
Heavy metals (HMs) in farmland soils lead to adverse influences on ecosystem and human health. Despite that, data on quantitative risk from different sources are still scarce. In this study, 100 farmland soil samples in Jiuyuan District were collected and analyzed for selected HMs (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, V and Zn) content characteristics and pollution statuses. The positive matrix factorization (PMF) model combined with the Nemerow integrated risk index (NIRI) and human health risk assessment (HHRA) was used to quantitatively identify the primary risk sources. The results indicated that the mean contents or median values (mg/kg) of 10 HMs were all higher than the background values. The contamination factor (CF) and pollution load index (PLI) revealed that the soil was severely polluted. Based on PMF, the main source of HM pollution was anthropogenic activities, accounting for 78.91%. Sewage irrigation represented the biggest input but was not associated with the highest risk. The results of PMF-based NIRI and PMF-based HHRA showed that the chemical fertilizers and pesticides were the largest and priority risk sources with contribution rates of 38.10% to ecological risk and 34.61 and 32.82% to non-carcinogenic and carcinogenic risk, respectively. In addition, non-carcinogenic risk of children was higher than that of adults, while the carcinogenic risk was the opposite. The integrated approaches were beneficial for priority risk quantification from different sources and can provide direct risk information and effective policy recommendations for management and control of key risk sources.
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Metais Pesados , Poluentes do Solo , Adulto , Criança , China , Ecossistema , Monitoramento Ambiental , Fazendas , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análiseRESUMO
Natural products (NPs) and their derivatives play a pivotal role in drug discovery due to their complexity and diversity. The strategies to rapidly generate NP-like compounds offer unique opportunities to access bioactive compounds. Here we present a new approach, precursor-assisted biosynthesis (PAB), for the creation of NP-like compounds by combination of artificial supplementation of common precursors and divergent post-modifications of precursor-deficient fungi. This method was applied to construct a meroterpenoid-like compound collection containing 43 compounds with diverse molecular scaffolds. Extensive bioactive screening of the collection revealed novel STING (stimulator of interferon genes) inhibitors, cytotoxic and antifungal compounds. This result indicates that PAB is an effective methodology for producing compound collections for the purpose of drug discovery.
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Produtos BiológicosRESUMO
Ibrutinib (IBT), the first-in-class inhibitor of Bruton's tyrosine kinase (BTK), has demonstrated clinical activity against various B-cell malignancies. Aside from its therapeutic mechanism through BTK inhibition, IBT has other target sites reported for cancer therapy, leading us to investigate whether IBT has unreported targets. Our study revealed that IBT can inhibit SMMC-7721 cells through irreversible inhibition of mammalian thioredoxin reductase enzymes. Further study demonstrated that IBT can cause cellular reactive oxygen species elevation and induce cancer cell apoptosis. The discovery of a new target of IBT sheds light on better understanding its anticancer mechanisms and provides a theoretical foundation for its further use in clinical therapy.
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Apoptose/efeitos dos fármacos , Terapia de Alvo Molecular , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Tiorredoxina Dissulfeto Redutase/metabolismo , Adenina/análogos & derivados , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Simulação de Acoplamento Molecular , Piperidinas , Conformação Proteica , Inibidores de Proteínas Quinases/metabolismo , Pirazóis/metabolismo , Pirimidinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/metabolismo , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Tiorredoxina Dissulfeto Redutase/químicaRESUMO
BACKGROUND: Raw rhubarb samples that have been subjected to different drying procedures will have different therapeutic effects, possibly due to processing-induced variations in the chemical composition. In the present work, the fresh materials were processed by smoking, sun-drying, shade-drying and oven-drying at low, moderate and high temperatures. To facilitate the selection of a suitable drying method for rhubarb, the quality of rhubarb processed under various drying conditions was evaluated based on the simultaneous determination of multiple bioactive constituents in combination with bioactivity assays. RESULTS: The total concentrations of 12 compounds in smoked rhubarb were higher than the concentrations of the same components in raw rhubarb and rhubarb products processed using other drying techniques. Smoked rhubarb was found to substantially inhibit Na+ /K+ -ATPase and thrombin. In addition, higher content of anthraquinones led to higher Na+ /K+ -ATPase inhibitory activities, and higher gallic acid content increased the antithrombin capacity. CONCLUSION: The results confirmed that post-harvest fresh plant materials, especially roots, were still physiologically active organs that could undergo series of anti-dehydration mechanisms, including the production of related secondary metabolites during the early stages of dehydration. Therefore, the proper design of drying processes could enhance the quality of rhubarb as well as other similar medicinal plants. © 2018 Society of Chemical Industry.
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Dessecação/métodos , Manipulação de Alimentos/métodos , Plantas Medicinais/química , Rheum/química , Antraquinonas/análise , Antitrombinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/análise , Fumaça , ATPase Trocadora de Sódio-Potássio/análise , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Trombina/análiseRESUMO
In this work, we developed a novel approach to evaluate the contents of bioactive components in rhubarb. The present method was based on the quantitative analysis of multicomponents by a single-marker and response surface methodology approaches. The quantitative analysis of multicomponents by a single-marker method based on high-performance liquid chromatography coupled with photodiode array detection was developed and applied to determine the contents of 12 bioactive components in rhubarb. No significant differences were found in the results from the quantitative analysis of multicomponents by a single-marker and the external standard method. In order to maximize the extraction of 12 bioactive compounds in rhubarb, the ultrasonic-assisted extraction conditions were obtained by the response surface methodology coupled with Box-Behnken design. According to the obtained results, we showed that the optimal conditions would be as follows: proportion of ethanol/water 74.39%, solvent-to-solid ratio 24.07:1 v/w, extraction time 51.13 min, and extraction temperature 63.61°C. The analytical scheme established in this research should be a reliable, convenient, and appropriate method for quantitative determination of bioactive compounds in rhubarb.
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Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/análise , Rheum/química , UltrassomRESUMO
As a type of secreted membrane vesicle, exosomes are an emerging mode of cell-to-cell communication. Yet as exosome samples are commonly contaminated with other extracellular vesicles, the biological roles of exosomes in regulating immunity and promoting oncogenesis remain controversial. Wondering whether existing methods could distort our view of exosome biology, we compared two direct methods for imaging extracellular vesicles and quantified the impact of different production and storage conditions on the quality of exosome samples. Scanning electron microscopy (SEM) was compared to transmission electron microscopy (TEM) as alternatives to examine the morphology of exosomes. Using SEM, we were able to distinguish exosomes from other contaminating extracellular vesicles based on the size distribution. More importantly, freezing of samples prior to SEM imaging made it more difficult to distinguish exosomes from extracellular vesicles secreted during cell death. In addition to morphology, the quality of RNA contained within the exosomes was characterized under different storage conditions, where freezing of samples also degraded RNA. Finally, we developed a new flow cytometry approach to assay transmembrane proteins on exosomes. While high-copy-number proteins could be readily detected, detecting low-copy-number proteins was improved using a lipophilic tracer that clustered exosomes. To illustrate this, we observed that exosomes derived from SKBR3 cells, a cell model for human HER2+ breast cancer, contained both HER1 and HER2 but at different levels of abundance. Collectively, these new methods will help to ensure a consistent framework to identify specific roles that exosomes play in regulating cell-to-cell communication.
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Exossomos/metabolismo , Exossomos/ultraestrutura , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , RNA/metabolismo , Animais , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Camundongos , TemperaturaRESUMO
Challenges in demonstrating durable clinical responses to molecular-targeted therapies have sparked a re-emergence in viewing cancer as an evolutionary process. In somatic evolution, cellular variants are introduced through a random process of somatic mutation and are selected for improved fitness through a competition for survival. In contrast to Darwinian evolution, cellular variants that are retained may directly alter the fitness competition. If cell-to-cell communication is important for selection, the biochemical cues secreted by malignant cells that emerge should be altered to bias this fitness competition. To test this hypothesis, we compared the proteins secreted in vitro by two human HER2+ breast cancer cell lines (BT474 and SKBR3) relative to a normal human mammary epithelial cell line (184A1) using a proteomics workflow that leveraged two-dimensional gel electrophoresis (2DE) and MALDI-TOF mass spectrometry. Supported by the 2DE secretome maps and identified proteins, the two breast cancer cell lines exhibited secretome profiles that were similar to each other and, yet, were distinct from the 184A1 secretome. Using protein-protein interaction and pathway inference tools for functional annotation, the results suggest that all three cell lines secrete exosomes, as confirmed by scanning electron microscopy. Interestingly, the HER2+ breast cancer cell line exosomes are enriched in proteins involved in antigen-processing and presentation and glycolytic metabolism. These pathways are associated with two of the emerging hallmarks of cancer: evasion of tumor immunosurveillance and deregulating cellular energetics.
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Comunicação Celular , Células Epiteliais/fisiologia , Exossomos/metabolismo , Proteínas/metabolismo , Proteoma/análise , Linhagem Celular Tumoral , Eletroforese em Gel Bidimensional , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Exossomos/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
AIM: To identify potential categories of clinical belonging among new nurses and explore the relationship between different categories and turnover intention. DESIGN: A cross sectional study. METHOD: A cross sectional study was conducted among 348 new nurses from tertiary hospitals in Hainan and Guangdong provinces. A general data questionnaire, clinical belonging scale and turnover intention scale were used for examination. Further, the potential categories were used to analyse the categories of clinical belonging, and latent class analysis was utilized to analyse the relationship between different categories of clinical belonging and turnover intention. RESULTS: The clinical sense of belonging of new nurses were divided into three groups namely C1, C2 and C3. The C1: poor clinical sense of belonging (8.7%), C2: moderate clinical sense of belonging (57.9%) and C3: rich clinical sense of belonging (33.4%). The risk of the turnover intention of new nurses with 'poor clinical sense of belonging' was 0.62 times that of new nurses with 'rich clinical sense of belonging' (OR = 0.62, p < 0.01), which was 0.24 times that of 'moderate clinical sense of belonging' (OR = 0.24, p < 0.01), the risk of the turnover intention of new nurses with 'moderate clinical sense of belonging' was 0.13 times that of new nurses with 'rich clinical sense of belonging'(OR = 0. 13, p < 0.01). CONCLUSIONS: The results of our study revealed that in order to enhance the new nurses' sense of belonging, support was most crucial when they were first encountering difficulties. To reduce turnover intention, more structured learning opportunities are also required to maximize learning for newly graduated nurses with various nursing degrees. PATIENT OR PUBLIC CONTRIBUTION: There are no patient or public contributions in this study.
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Intenção , Enfermeiras e Enfermeiros , Humanos , Análise de Classes Latentes , Estudos Transversais , AprendizagemRESUMO
Viral myocarditis (VMC) is one of the most common acquired heart diseases in children and teenagers. However, its pathogenesis is still unclear, and effective treatments are lacking. This study aimed to investigate the regulatory pathway by which exosomes alleviate ferroptosis in cardiomyocytes (CMCs) induced by coxsackievirus B3 (CVB3). CVB3 was utilized for inducing the VMC mouse model and cellular model. Cardiac echocardiography, left ventricular ejection fraction (LVEF), and left ventricular fractional shortening (LVFS) were implemented to assess the cardiac function. In CVB3-induced VMC mice, cardiac insufficiency was observed, as well as the altered levels of ferroptosis-related indicators (glutathione peroxidase 4 (GPX4), glutathione (GSH), and malondialdehyde (MDA)). However, exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs-exo) could restore the changes caused by CVB3 stimulation. Let-7a-5p was enriched in hucMSCs-exo, and the inhibitory effect of hucMSCs-exolet-7a-5p mimic on CVB3-induced ferroptosis was higher than that of hucMSCs-exomimic NC (NC: negative control). Mothers against decapentaplegic homolog 2 (SMAD2) increased in the VMC group, while the expression of zinc-finger protein 36 (ZFP36) decreased. Let-7a-5p was confirmed to interact with SMAD2 messenger RNA (mRNA), and the SMAD2 protein interacted directly with the ZFP36 protein. Silencing SMAD2 and overexpressing ZFP36 inhibited the expression of ferroptosis-related indicators. Meanwhile, the levels of GPX4, solute carrier family 7, member 11 (SLC7A11), and GSH were lower in the SMAD2 overexpression plasmid (oe-SMAD2)+let-7a-5p mimic group than in the oe-NC+let-7a-5p mimic group, while those of MDA, reactive oxygen species (ROS), and Fe2+ increased. In conclusion, these data showed that ferroptosis could be regulated by mediating SMAD2 expression. Exo-let-7a-5p derived from hucMSCs could mediate SMAD2 to promote the expression of ZFP36, which further inhibited the ferroptosis of CMCs to alleviate CVB3-induced VMC.
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Exossomos , Ferroptose , Células-Tronco Mesenquimais , MicroRNAs , Miócitos Cardíacos , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Infecções por Coxsackievirus/patologia , Enterovirus Humano B/fisiologia , Exossomos/metabolismo , Ferroptose/efeitos dos fármacos , Células-Tronco Mesenquimais/química , MicroRNAs/farmacologia , Miocardite/tratamento farmacológico , Miócitos Cardíacos/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Proteína Smad2/metabolismo , Cordão Umbilical/citologiaRESUMO
BACKGROUND: Gastric cancer (GC) has a poor prognosis because it is highly aggressive, yet there are currently few effective therapies available. Although protein ubiquitination has been shown to play a complex role in the development of gastric cancer, to date, no efficient ubiquitinating enzymes have been identified as treatment targets for GC. METHODS: The TCGA database was used for bioinformatic investigation of ubiquitin-specific protease 31 (USP31) expression in GC, and experimental techniques, including Western blotting, qRT-PCR, and immunohistochemistry, were used to confirm the findings. We also analyzed the relationship between USP31 expression and clinical prognosis in patients with GC. We further investigated the effects of USP31 on the proliferation, invasion, migration, and glycolysis of GC cells in vitro and in vivo by using colony formation, CCK-8 assays, Transwell chamber assays, cell scratch assays, and cell-derived xenograft. Furthermore, we examined the molecular processes by which USP31 influences the biological development of GC. RESULTS: Patients with high USP31 expression have a poor prognosis because USP31 is abundantly expressed in GC. Therefore, USP31 reduces the level of ubiquitination of the Wnt/ß-catenin pathway by binding to ß-catenin, thereby activating glycolysis, which ultimately promotes GC proliferation and aggressive metastasis. CONCLUSION: USP31 inhibits ubiquitination of ß-catenin by binding to it, stimulates the Wnt/ß-- catenin pathway, activates glycolysis, and accelerates the biology of GCs, which are all demonstrated in this work.
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Polylactic acid (PLA) is a biodegradable polyester polymer that is produced from renewable resources, such as corn or other carbohydrate sources. However, its poor toughness limits its commercialization. PLA composites can meet the growing performance needs of various fields, but limited research has focused on their sustainable applications in sports. This paper reviews the latest research on PLA and its composites by describing the characteristics, production, degradation process, and the latest modification methods of PLA. Then, it discusses the inherent advantages of PLA composites and expounds on different biodegradable materials and their relationship with the properties of PLA composites. Finally, the importance and application prospects of PLA composites in the field of sports are emphasized. Although PLA composites mixed with natural biomass materials have not been mass produced, they are expected to be sustainable materials used in various industries because of their simple process, nontoxicity, biodegradability, and low cost.
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The interrelationship between regional water, energy, food, and land systems is extremely complex. Hence, accurately assessing the coupling coordination relationship and identifying the influential factors of the water-energy-food-land nexus (WEFL nexus) are of utmost importance. This study proposes a novel analytical framework and evaluation index system for exploring interactions across the WEFL nexus. The comprehensive benefit evaluation index (CBEI), coupling coordination degree (CCD) model, and obstacle factor diagnosis model are integrated to assess and analyze the coupling coordination relationship and spatiotemporal dynamic evolution of the WEFL nexus in the Yangtze River Economic Belt (YREB) from 2006 to 2020. The results indicated that (1) the CBEI and CCD generally increased from 0.23 to 0.79 and 0.45 to 0.88, respectively, revealing the upward trend of the coordination development levels of the WEFL nexus in the YREB. (2) The lower reaches achieved a relatively higher coordination development degree than the upper and middle reaches of the YREB. (3) The findings of obstacle factors reveal that agricultural non-point source pollution control, waterlogging disaster prevention, industrial solid waste efficient treatment, and urban water-saving are the essential fields that need to be improved in YREB's future development. This study helps to understand the complex interrelation of the WEFL nexus at different spatial-temporal scales and provides a novel framework that can be used as an evaluation system and policy insights for a region's integrated resources, environmental management, and green sustainable development.
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Rios , Água , China , Conservação dos Recursos Naturais , Desenvolvimento Sustentável , Desenvolvimento Econômico , CidadesRESUMO
This work describes an original and simple technique for protein immobilization into nanowells, fabricated using nanopatterned array fabrication methods, while ensuring the protein retains normal biological activity. Nanosphere lithography was used to fabricate a nanowell array with nanowells 100 nm in diameter with a periodicity of 500 nm. The base of the nanowells was gold and the surrounding material was silicon dioxide. The different surface chemistries of these materials were used to attach two different self-assembled monolayers (SAM) with different affinities for the protein used here, cytochrome P450 (P450). The nanowell SAM, a methyl terminated thiol, had high affinity for the P450. The surrounding SAM, a polyethylene glycol silane, displayed very little affinity toward the P450 isozyme CYP2C9, as demonstrated by x-ray photoelectron spectroscopy and surface plasmon resonance. The regularity of the nanopatterned array was examined by scanning electron microscopy and atomic force microscopy. P450-mediated metabolism experiments of known substrates demonstrated that the nanowell bound P450 enzyme exceeded its normal activity, as compared to P450 solutions, when bound to the methyl terminated self-assembled monolayer. The nanopatterned array chips bearing P450 display long term stability and give reproducible results making them potentially useful for high-throughput screening assays or as nanoelectrode arrays.
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Cristalização/métodos , Sistema Enzimático do Citocromo P-450/química , Impressão Molecular/métodos , Nanosferas/química , Nanosferas/ultraestrutura , Poliestirenos/química , Análise Serial de Proteínas/instrumentação , Sistema Enzimático do Citocromo P-450/ultraestrutura , Desenho de Equipamento , Análise de Falha de Equipamento , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Fotografação/métodos , Propriedades de SuperfícieRESUMO
Skeletal muscles exhibit excellent properties due to their well-developed microstructures. Taking inspiration from nature that thick filaments and thin filaments are linked by "cross-bridges", leading to good stability and ion transport performance of muscles. In this work, extracted poplar lignin and microcrystalline cellulose (MCC) were connected by biomimetic covalent bonds, akin to biological muscle tissue, in which isophorone diisocyanate was used as the chemical crosslinking agent. Then, poplar lignin-MCC was mixed with polyacrylonitrile to serve as the precursor for electrospinning. The results show that due to the effective covalent-bond connection, the precursor fibers possess excellent morphology, smooth surface, good thermal stability, and high flexibility and toughness (average elongation-at-break is 51.84%). Therefore, after thermal stabilization and carbonization, derived lignocellulose-based carbon fibers (CFs) with a reduced cost, complete fiber morphology with a uniform diameter (0.48 ± 0.22 µm), and high graphitization degree were obtained. Finally, the electrodes fabrication and electrochemical testing were carried out. The results of electrochemical impedance spectroscopy (EIS) indicate that the Rs and Rct values of CFs supercapacitors are 1.18 Ω and 0.14 Ω, respectively. Results of cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) suggest that these CFs demonstrate great application potential in electrochemical materials.
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Driven by various environmental and economic factors, it is emerging to adopt an efficient and sustainable strategy to recycle carbon fibers (rCFs) from carbon fiber-reinforced polymer (CFRP) wastes and reuse them in high-value applications. This review summarized the latest progress of CFRP waste recycling methods (including mechanical, chemical, and thermal methods), discussed their advantages and disadvantages, influence parameters and possible environmental effects, and their potential effects on the mechanical and surface chemical properties of rCFs. In addition, the latest optimization schemes of leading recycling technologies were detailed. According to the literature, CFs are the key points in the structural support of semiconductor-based recyclable photocatalytic systems and the enhancement of performance, which means that rCFs have high reuse potential in sustainable photocatalysis. Therefore, this paper also emphasized the possibility and potential value of reusing recovered fibers for developing recyclable photocatalytic products, which may be a new way of reuse in environmental purification often ignored by researchers and decision-makers in the field of CFs.
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At present, high-performance carbon fibers (CFs) are mainly produced from petroleum-based materials. However, the high costs and environmental problems of the production process prompted the development of new precursors from natural biopolymers. This review focuses on the latest research on the conversion of natural lignocellulosic biomass into precursor fibers and CFs. The influence of the properties, advantages, separation, and extraction of lignin and cellulose (the most abundant natural biopolymers), as well as the spinning process on the final CF performance are detailed. Recent strategies to further improve the quality of such CFs are discussed. The importance and application of CFs in sports equipment manufacturing are briefly summarized. While the large-scale production of CFs from natural lignocellulosic biomass and their applications in sports equipment have not yet been realized, CFs still provide a promising market prospect as green and low-cost materials. Further research is needed to ensure the market entry of lignocellulosic biomass-based CFs.