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Ebola virus nucleoprotein (eNP) assembles into higher-ordered structures that form the viral nucleocapsid (NC) and serve as the scaffold for viral RNA synthesis. However, molecular insights into the NC assembly process are lacking. Using a hybrid approach, we characterized the NC-like assembly of eNP, identified novel regulatory elements, and described how these elements impact function. We generated a three-dimensional structure of the eNP NC-like assembly at 5.8 Å using electron cryo-microscopy and identified a new regulatory role for eNP helices α22-α23. Biochemical, biophysical, and mutational analyses revealed that inter-eNP contacts within α22-α23 are critical for viral NC assembly and regulate viral RNA synthesis. These observations suggest that the N terminus and α22-α23 of eNP function as context-dependent regulatory modules (CDRMs). Our current study provides a framework for a structural mechanism for NC-like assembly and a new therapeutic target.
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Microscopia Crioeletrônica , Ebolavirus/fisiologia , Ebolavirus/ultraestrutura , Nucleocapsídeo/ultraestrutura , Nucleoproteínas/ultraestrutura , Montagem de Vírus , Modelos Biológicos , Proteínas Mutantes/química , Mutação/genética , Nucleoproteínas/química , Multimerização Proteica , Estrutura Secundária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , RNA Viral/biossíntese , RNA Viral/química , RNA Viral/metabolismoRESUMO
Type VI secretion systems (T6SSs) are newly identified contractile nanomachines that translocate effector proteins across bacterial membranes. The Francisella pathogenicity island, required for bacterial phagosome escape, intracellular replication, and virulence, was presumed to encode a T6SS-like apparatus. Here, we experimentally confirm the identity of this T6SS and, by cryo electron microscopy (cryoEM), show the structure of its post-contraction sheath at 3.7 Å resolution. We demonstrate the assembly of this T6SS by IglA/IglB and secretion of its putative effector proteins in response to environmental stimuli. The sheath has a quaternary structure with handedness opposite that of contracted sheath of T4 phage tail and is organized in an interlaced two-dimensional array by means of ß sheet augmentation. By structure-based mutagenesis, we show that this interlacing is essential to secretion, phagosomal escape, and intracellular replication. Our atomic model of the T6SS will facilitate design of drugs targeting this highly prevalent secretion apparatus.
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Proteínas de Bactérias/química , Sistemas de Secreção Bacterianos , Francisella/ultraestrutura , Proteínas de Bactérias/ultraestrutura , Bacteriófago T4/química , Bacteriófagos/química , Microscopia Crioeletrônica , Modelos Moleculares , Estrutura Secundária de ProteínaRESUMO
Frontotemporal lobar degeneration (FTLD) is the third most common neurodegenerative condition after Alzheimer's and Parkinson's diseases1. FTLD typically presents in 45 to 64 year olds with behavioural changes or progressive decline of language skills2. The subtype FTLD-TDP is characterized by certain clinical symptoms and pathological neuronal inclusions with TAR DNA-binding protein (TDP-43) immunoreactivity3. Here we extracted amyloid fibrils from brains of four patients representing four of the five FTLD-TDP subclasses, and determined their structures by cryo-electron microscopy. Unexpectedly, all amyloid fibrils examined were composed of a 135-residue carboxy-terminal fragment of transmembrane protein 106B (TMEM106B), a lysosomal membrane protein previously implicated as a genetic risk factor for FTLD-TDP4. In addition to TMEM106B fibrils, we detected abundant non-fibrillar aggregated TDP-43 by immunogold labelling. Our observations confirm that FTLD-TDP is associated with amyloid fibrils, and that the fibrils are formed by TMEM106B rather than TDP-43.
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Amiloide , Proteínas de Ligação a DNA , Degeneração Lobar Frontotemporal , Proteínas de Membrana , Proteínas do Tecido Nervoso , Amiloide/ultraestrutura , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/ultraestrutura , Degeneração Lobar Frontotemporal/metabolismo , Degeneração Lobar Frontotemporal/patologia , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/ultraestrutura , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/ultraestruturaRESUMO
R-type bacteriocins are minimal contractile nanomachines that hold promise as precision antibiotics1-4. Each bactericidal complex uses a collar to bridge a hollow tube with a contractile sheath loaded in a metastable state by a baseplate scaffold1,2. Fine-tuning of such nucleic acid-free protein machines for precision medicine calls for an atomic description of the entire complex and contraction mechanism, which is not available from baseplate structures of the (DNA-containing) T4 bacteriophage5. Here we report the atomic model of the complete R2 pyocin in its pre-contraction and post-contraction states, each containing 384 subunits of 11 unique atomic models of 10 gene products. Comparison of these structures suggests the following sequence of events during pyocin contraction: tail fibres trigger lateral dissociation of baseplate triplexes; the dissociation then initiates a cascade of events leading to sheath contraction; and this contraction converts chemical energy into mechanical force to drive the iron-tipped tube across the bacterial cell surface, killing the bacterium.
Assuntos
Pseudomonas aeruginosa , Piocinas/química , Piocinas/metabolismo , Bacteriófago T4/química , Bacteriófago T4/metabolismo , Microscopia Crioeletrônica , Cristalografia por Raios X , Genes Bacterianos/genética , Modelos Moleculares , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Pseudomonas aeruginosa/química , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Especificidade por Substrato , Sistemas de Secreção Tipo VI/química , Sistemas de Secreção Tipo VI/metabolismoRESUMO
Heterogeneous nuclear ribonucleoprotein A2 (hnRNPA2) is a human ribonucleoprotein that transports RNA to designated locations for translation via its ability to phase separate. Its mutated form, D290V, is implicated in multisystem proteinopathy known to afflict two families, mainly with myopathy and Paget's disease of bone. Here, we investigate this mutant form of hnRNPA2 by determining cryo-EM structures of the recombinant D290V low complexity domain. We find that the mutant form of hnRNPA2 differs from the WT fibrils in four ways. In contrast to the WT fibrils, the PY-nuclear localization signals in the fibril cores of all three mutant polymorphs are less accessible to chaperones. Also, the mutant fibrils are more stable than WT fibrils as judged by phase separation, thermal stability, and energetic calculations. Similar to other pathogenic amyloids, the mutant fibrils are polymorphic. Thus, these structures offer evidence to explain how a D-to-V missense mutation diverts the assembly of reversible, functional amyloid-like fibrils into the assembly of pathogenic amyloid, and may shed light on analogous conversions occurring in other ribonucleoproteins that lead to neurological diseases such as amyotrophic lateral sclerosis and frontotemporal dementia.
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Microscopia Crioeletrônica , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B , Modelos Moleculares , Humanos , Separação de Fases , Domínios Proteicos , Mutação , Concentração de Íons de Hidrogênio , Estabilidade Proteica , Estrutura Terciária de Proteína , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/química , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismoRESUMO
Spent graphite, as the main component of retired batteries, have attracted plenty of attentions. Although a series of recycling strategies are proposed, they still suffer from high cost of regeneration and large CO2 emission, mainly ascribed to the full-recovery of surface and internal phase at ultra-high temperature. However, the existing of suitable internal defects is conductive to their energy-storage abilities. Herein, with the introduction of Fe-based catalysts, spent graphite is successfully repaired at low temperature with the tailored surface traits, including conductivities, isotropy and so on. As Li-storage anodes, all of samples can display a capacity of 340 mAh g-1 above at 1.0 C after 200 cycles. At high rate 5.0 C, their capacity can be also kept ≈300 mAh g-1, and remained ≈233 mAh g-1 even after 1000 cycles. Assisted by electrochemical and kinetic behaviors, their cycling traits with dynamic surface transformations are detailed explored, including activated/fading mechanism, Li-depositions forming etc. Moreover, the calculated constant time of as-optimized regenerated sample is ≈3.0 × 10-4 s, further revealing the importance of surface designing. Therefore, the work is expected to shed light on their energy-storage behaviors, and offer low-temperature regenerated strategies of spent graphite with high value.
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Captured by high theoretical capacity and low-cost, Sodium-Sulfur (Na-S) batteries have been deemed as promising energy-storage systems. However, their electrochemical properties, containing both cycling and rate properties, still suffer from the notorious "shuttle effect" of polysulfide. Herein, through the effective regulation of pore sizes, a series of S/SiO2 cathode materials are obtained. Benefitting from the abundant pore channels of SiO2 particles, the sulfur loading is as high as 76.3%. Importantly, a suitable pore size can lead to adequate reaction and rapid diffusion behaviors, resulting in excellent electrochemical performances. Specifically, at 2.0 A g-1, the initial capacity of the as-optimized sample can be up to 1370.6 mAh g-1. Surprisingly, even after 1050 cycles, it could achieve a high reversible capacity of 1280.8 mAh g-1 with an attenuation rate of 0.089%. At 5.0 A g-1, after 500 cycles, the capacity can still remain ≈ 1132.6 mAh g-1 (capacity retention rate, 97.5%). Given this, the work is anticipated to offer an effective strategy for advanced electrodes for Na-S batteries.
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INTRODUCTION: Around 20% of individuals diagnosed with acute pancreatitis (AP) may develop severe acute pancreatitis (SAP), possibly resulting in a mortality rate ranging from 15% to 35%. There is an urgent need to thoroughly understand the molecular phenotypes of SAP resulting from diverse etiologies. The field of translational research on AP has seen the use of several innovative proteomic methodologies via the ongoing improvement of isolation, tagging, and quantification methods. AREAS COVERED: This paper provides a comprehensive overview of differentially abundant proteins (DAPs) identified in AP by searching the PubMed/MEDLINE database (2003-2023) and adds significantly to the current theoretical framework. EXPERT OPINION: DAPs for potentially diagnosing AP based on proteomic identification need to be confirmed by multi-center studies that include larger samples. The discovery of DAPs in various organs at different AP stages via proteomic technologies is essential better to understand the pathophysiology of AP-related multiple organ dysfunction syndrome. Regarding the translational research of AP, novel approaches like single-cell proteomics and imaging using mass spectrometry may be used as soon as they become available.
Assuntos
Pancreatite , Humanos , Pancreatite/diagnóstico , Pancreatite/complicações , Pancreatite/metabolismo , Proteômica , Doença Aguda , Insuficiência de Múltiplos ÓrgãosRESUMO
Commonly utilized as a plasticizer in the food and chemical sectors, Dibutyl phthalate (DBP) poses threats to the environment and human well-being as it seeps or moves into the surroundings. Nevertheless, research on the harmfulness of DBP to aquatic organisms is limited, and its impact on stem cells and tissue regeneration remains unidentified. Planarians, recognized for their robust regenerative capabilities and sensitivity to aquatic pollutants, are emerging animal models in toxicology. This study investigated the comprehensive toxicity effects of environmentally relevant levels of DBP on planarians. It revealed potential toxicity mechanisms through the use of immunofluorescence, chromatin dispersion assay, Western blot, quantitative real-time fluorescence quantitative PCR (qRT-PCR), chromatin behavioral and histological analyses, immunofluorescence, and terminal dUTP nickel-end labeling (TUNEL). Findings illustrated that DBP caused morphological and motor abnormalities, tissue damage, regenerative inhibition, and developmental neurotoxicity. Further research revealed increased apoptosis and suppressed stem cell proliferation and differentiation, disrupting a balance of cell proliferation and death, ultimately leading to morphological defects and functional abnormalities. This was attributed to oxidative stress and DNA damage caused by excessive release of reactive oxygen species (ROS). This exploration furnishes fresh perspectives on evaluating the toxicity peril posed by DBP in aquatic organisms.
Assuntos
Dibutilftalato , Planárias , Regeneração , Poluentes Químicos da Água , Animais , Dibutilftalato/toxicidade , Planárias/efeitos dos fármacos , Planárias/fisiologia , Poluentes Químicos da Água/toxicidade , Regeneração/efeitos dos fármacos , Ecotoxicologia , Estresse Oxidativo/efeitos dos fármacos , Plastificantes/toxicidade , Apoptose/efeitos dos fármacosRESUMO
The current solar-chemical-industry based on semiconductor photocatalyst is impractical. Metal catalysts are extensively employed in thermal- and electro-catalysis industries, but unsuitable for direct-driven photocatalysis. Herein, silver quantum dots (Ag-QDs) are synthesized on support via an in situ photoreduction method, and in situ photocatalysis temperature programmed dynamics chemisorption desorption analyses are designed to demonstrate that Ag-QDs should be the actual photocatalytic sites. The surface plasmon resonance of Ag-QDs could harvests entire visible solar, and the plasmon-driven charge-transfer exhibits opposite directions at the interface when supports are different. Consequently, Ag-QDs could be alternatively regulated as oxidation or reduction active centers. Furthermore, Ag-QDs excite electron tunneling transfer with adsorbate, which does not generate high-energy free-radical intermediates. As a result, the efficiencies of hydrocarbon photooxidation and CO2 photoreduction are improved in several orders of magnitude. Evidently, the Ag-QDs direct photocatalytic technology greatly promotes solar-chemical-industry applications.
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Nonsmall cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. Circular RNAs (circRNAs) have been the focus of numerous studies, and some circRNAs have been linked to the development of multiple malignant tumors, including NSCLC. Nevertheless, the functional role and mechanisms of circRNAs in NSCLC remain largely unknown. The primary objective of this study was to screen the associated circRNA in NSCLC and investigate its mechanism. CircRNA microarray was used to identify circRNAs that were abnormally expressed in NSCLC tissue samples. Expression of hsa_circRNA_0088036 was validated in NSCLC tissues and cell lines after the correlation between hsa_circRNA_0088036 and prognosis was determined. We then used a series of function gain-and-loss assays to determine the role of hsa_circ_0088036 in NSCLC progression. RNA-binding protein immunoprecipitation (RIP), RNA pull-down, and RNA interference assays were used to assess the interaction between hsa_circ_0088036 and miR-1343-3p/Bcl-3 axis. Moreover, mechanistic assays were applied to investigate the involved signaling pathway regulated by the hsa_circ_0088036/miR-1343-3p/Bcl-3 axis. Microarray analysis and reverse transcription polymerase chain reaction confirmed the presence of a circRNA termed hsa_circ 0088036 that was upregulated in NSCLC tissue samples and cell lines and indicated a positive association with patient prognosis. Functionally, hsa_circ_0088036 silencing inhibited proliferative, invasive, and migrative potential of NSCLC cells as well as epithelial-mesenchymal transition (EMT)-related proteins by sponging miR-1343-3p to inhibit Bcl-3. Furthermore, mechanistic experiments demonstrated that hsa_circ_0088036 promoted NSCLC progression by activating the TGFß/Smad3/EMT signaling pathway via miR-1343-3p/Bcl-3 axis. In conclusion, hsa_circ_0088036 functions as an oncogene by targeting the miR-1343-3p/Bcl-3 axis via TGFß/Smad3/EMT signaling pathway.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , Fator de Crescimento Transformador beta/genéticaRESUMO
The impact of severe acute respiratory syndrome coronavirus 2 infection on the potential development of pancreatitis is a subject of ongoing debate within academic discourse. Establishing a causal link between COVID-19 and pancreatitis may not be fully supported by relying only on retrospective studies or case reports. This study examined the relationship between COVID-19 phenotypes and pancreatitis by Mendelian randomization (MR) method. The identification of instrumental variables (single nucleotide polymorphisms) that exhibit a robust association with the COVID-19 phenotypes was accomplished through a meticulous process of rigorous screening procedures. We included acute pancreatitis and chronic pancreatitis (CP) as the outcomes in the MR analysis, even though no definitive studies exist between COVID-19 and CP. A direct causal relationship between genetically predicted COVID-19 phenotypes and pancreatitis risk cannot be established. There is an ongoing debate over the designation of COVID-19 as a definitive cause of pancreatitis.
Assuntos
COVID-19 , Pancreatite , Humanos , Doença Aguda , COVID-19/complicações , Estudo de Associação Genômica Ampla , Fenótipo , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Análise da Randomização MendelianaRESUMO
This paper presents a method for measuring the optical assembly results based on multi-beam biaxial LiDAR. This method analyzes the optical assembly parameters of a LiDAR system affecting the LiDAR operation, and an experimental measurement system is built using a collimator to simulate the infinity imaging field. An InGaAs infrared camera is used to take pictures of the laser spot from the LiDAR transmitter and receiver, and then fit the laser spot images with Gaussian equations to calculate the biaxial LiDAR optical assembly results. Finally, the possible effecting factors of LiDAR alignment results are analyzed. This method is experimentally proven to achieve the measurement of the optical assembly results of a large scale multi-beam LiDAR. The possibility of further optimizing the measurement method by shaping the transmit laser is also reported.
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Parthanatos is a type of programmed cell death initiated by over-activated poly (ADP-ribose) polymerase 1 (PARP1). Nuclear translocation of apoptosis inducing factor (AIF) is a prominent feature of parthanatos. But it remains unclear how activated nuclear PARP1 induces mitochondrial AIF translocation into nuclei. Evidence has shown that deoxypodophyllotoxin (DPT) induces parthanatos in glioma cells via induction of excessive ROS. In this study we explored the downstream signal of activated PARP1 to induce nuclear translocation of AIF in DPT-triggered glioma cell parthanatos. We showed that treatment with DPT (450 nM) induced PARP1 over-activation and Tax1 binding protein 1 (TAX1BP1) distribution to mitochondria in human U87, U251 and U118 glioma cells. PARP1 activation promoted TAX1BP1 distribution to mitochondria by depleting nicotinamide adenine dinucleotide (NAD+). Knockdown of TAX1BP1 with siRNA not only inhibited TAX1BP1 accumulation in mitochondria, but also alleviated nuclear translocation of AIF and glioma cell death. We demonstrated that TAX1BP1 enhanced the activity of respiratory chain complex I not only by upregulating the expression of ND1, ND2, NDUFS2 and NDUFS4, but also promoting their assemblies into complex I. The activated respiratory complex I generated more superoxide to cause mitochondrial depolarization and nuclear translocation of AIF, while the increased mitochondrial superoxide reversely reinforced PARP1 activation by inducing ROS-dependent DNA double strand breaks. In mice bearing human U87 tumor xenograft, administration of DPT (10 mg· kg-1 ·d-1, i.p., for 8 days) markedly inhibited the tumor growth accompanied by NAD+ depletion, TAX1BP1 distribution to mitochondria, AIF distribution to nuclei as well as DNA DSBs and PARP1 activation in tumor tissues. Taken together, these data suggest that TAX1BP1 acts as a downstream signal of activated PARP1 to trigger nuclear translocation of AIF by activation of mitochondrial respiratory chain complex I.
Assuntos
Glioma , Parthanatos , Humanos , Camundongos , Animais , Fator de Indução de Apoptose/genética , Superóxidos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NAD/metabolismo , Transporte de Elétrons , Complexo I de Transporte de Elétrons , Glioma/metabolismo , Proteínas de Neoplasias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismoRESUMO
Parthanatos is a type of programmed cell death dependent on hyper-activation of poly (ADP-ribose) polymerase 1 (PARP-1). SIRT1 is a highly conserved nuclear deacetylase and often acts as an inhibitor of parthanatos by deacetylation of PARP1. Our previous study showed that deoxypodophyllotoxin (DPT), a natural compound isolated from the traditional herb Anthriscus sylvestris, triggered glioma cell death via parthanatos. In this study, we investigated the role of SIRT1 in DPT-induced human glioma cell parthanatos. We showed that DPT (450 nmol/L) activated both PARP1 and SIRT1, and induced parthanatos in U87 and U251 glioma cells. Activation of SIRT1 with SRT2183 (10 µmol/L) enhanced, while inhibition of SIRT1 with EX527 (200 µmol/L) or knockdown of SIRT1 attenuated DPT-induced PARP1 activation and glioma cell death. We demonstrated that DPT (450 nmol/L) significantly decreased intracellular NAD+ levels in U87 and U251 cells. Further decrease of NAD+ levels with FK866 (100 µmol/L) aggravated, but supplement of NAD+ (0.5, 2 mmol/L) attenuated DPT-induced PARP1 activation. We found that NAD+ depletion enhanced PARP1 activation via two ways: one was aggravating ROS-dependent DNA DSBs by upregulation of NADPH oxidase 2 (NOX2); the other was reinforcing PARP1 acetylation via increase of N-acetyltransferase 10 (NAT10) expression. We found that SIRT1 activity was improved when being phosphorylated by JNK at Ser27, the activated SIRT1 in reverse aggravated JNK activation via upregulating ROS-related ASK1 signaling, thus forming a positive feedback between JNK and SIRT1. Taken together, SIRT1 activated by JNK contributed to DPT-induced human glioma cell parthanatos via initiation of NAD+ depletion-dependent upregulation of NOX2 and NAT10.
Assuntos
Glioma , Parthanatos , Sirtuína 1 , Humanos , Glioma/tratamento farmacológico , Acetiltransferases N-Terminal/genética , Acetiltransferases N-Terminal/metabolismo , NAD/metabolismo , NADPH Oxidase 2/metabolismo , Parthanatos/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/metabolismo , Regulação para CimaRESUMO
Lidar presents a promising solution for bird surveillance in airport environments. However, the low observation refresh rate of Lidar poses challenges for tracking bird targets. To address this problem, we propose a gated recurrent unit (GRU)-based interacting multiple model (IMM) approach for tracking bird targets at low sampling frequencies. The proposed method constructs various GRU-based motion models to extract different motion patterns and to give different predictions of target trajectory in place of traditional target moving models and uses an interacting multiple model mechanism to dynamically select the most suitable GRU-based motion model for trajectory prediction and tracking. In order to fuse the GRU-based motion model and IMM, the approximation state transfer matrix method is proposed to transform the prediction of GRU-based network into an explicit state transfer model, which enables the calculation of the models' probability. The simulation carried out on an open bird trajectory dataset proves that our method outperforms classical tracking methods at low refresh rates with at least 26% improvement in tracking error. The results show that the proposed method is effective for tracking small bird targets based on Lidar systems, as well as for other low-refresh-rate tracking systems.
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Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP).
Assuntos
Lesão Pulmonar Aguda , Pancreatite , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Sepse , Humanos , Glucocorticoides/uso terapêutico , Doença Aguda , Pancreatite/complicações , Síndrome do Desconforto Respiratório/patologia , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/complicações , Sepse/complicaçõesRESUMO
municipal solid waste incineration (MSWI) fly ash partially replaces cement to solidify sediment, and then can be used as intermediate cover materials in landfill as one of the resources utilization ways of MSWI fly ash and sediment. The strength and the semi-dynamic leaching characteristics of MSWI fly ash solidified sediment under hydrochloric acid attack at different pH were studied by means of unconfined compressive strength (UCS), semi-dynamic leaching, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Thermogravimetric analysis (TGA). Results revealed that the UCS strength increased as the curing age and cement content increased. When the curing content is 50% and the replacement ratio of MSWI fly ash is 75% and 80%, the UCS of 7 d can be greater than 50 kPa. The primary contribution to the strength development was from silicic acid gels such as calcium silicate hydrate (C-S-H) and carbonates. Notably, the leaching behavior of Zn and Cu within the solidified sediment underwent substantial alterations. The leaching amount of heavy metals in a strong acidic environment (pH = 2) is significantly greater than that in a weak acidic (pH = 4) and neutral (pH = 7) environment. Conversely, minimal disparities were observed in the leaching characteristics of Zn and Cu between the weakly acidic and neutral environments. Ca(OH)2, C-S-H and carbonate exhibits a remarkable acid-resistant buffering capacity in the solidified sediment. The obvious diffusion coefficient (Dobs) was less than 10-9 m2/s in semi-dynamic leaching tests. Moreover, the mobility of Zn and Cu surpassing 12.5, coupled with a leaching index exceeding 8, further attests to the favorable S/S outcome achieved. Based on these findings, the solidified material is confidently recommended to be used as suitable landfill middle soil cover material.
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Metais Pesados , Eliminação de Resíduos , Cinza de Carvão/química , Incineração , Resíduos Sólidos/análise , Material Particulado , Carbono/química , Metais Pesados/análiseRESUMO
The recycling of spent lithium-ion batteries (LIBs) has attracted great attention, mainly because of its significant impact on resource recycling and environmental protection. Currently, the processes involved in recovering valuable metals from spent LIBs have shown remarkable progress, but little attention has been paid to the effective separation of spent cathode and anode materials. Significantly, it not only can reduce the difficulty in the subsequent processing of spent cathode materials, but also contribute to the recovery of graphite. Considering the difference in their chemical properties on the surface, flotation is an effective method to separate materials, owing to its low-cost and eco-friendly characteristics. In this paper, the chemical principles of flotation separation for spent cathodes and materials from spent LIBs is summarized first. Then, the research progress in flotation separation of various spent cathode materials (LiCoO2, LiNixCoyMnzO2, and LiFePO4) and graphite is summarized. Given this, the work is expected to offer the significant reviews and insights about the flotation separation for high-value recycling of spent LIBs.
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Metal sulfides, as vital members of electrodes materials, still suffer from serious volume expansion and polysulfides shuttling. Herein, through inexpensive and high efficiency chemical-bonding/hydrophobic-association methods, a series of metal-sulfides quantum dots (QDs) with large-scale synthesis (≈100 g) is successfully prepared, further forming low-dimensional composites with high redox activity. For the derived electrodes samples, with the increasing of outer electron numbers (Co2+ /Ni2+ /Cu2+ /Zn2+ ), interfacial coupling is significantly modified. Among them, nanoscale ZnS@double carbon with rich interfacial Zn-O/S-C bonds displays remarkable electrochemical activity, with the capacity of ≈1000 mAh g-1 after 100 loops. Through tailoring double carbons and interfacial merits, in situ sulfur formation is stabilized, and the cycling stability of Zn-based samples can increase up to 4000 cycles. Even at 5.0 A g-1 after 1500 cycles, the full-cells capacity can reach up to ≈380 mAh g-1 . Supported by detailed kinetic analysis and ex situ technologies, the enhanced interfacial capacitances and ions moving are confirmed for the improved electrochemical properties. Given this, the work is expected to boost future developments of mineral processing, and QDs preparation, whilst providing effective strategies for advanced electrode materials.