This study examines how the COVID-19 pandemic has affected the connectedness between non-fungible tokens, decentralized finance coins, traditional financial assets, and cryptocurrencies. We employed ...a time-varying parameter vector autoregressive based frequency-dependent network connectedness approach to investigate return and volatility spillover effects between assets in time and frequency domains. The findings show that both the returns and volatility spillovers have been significantly affected by the COVID-19 pandemic, and long- and short-term connectedness vary over the course of the pandemic. These findings have implications for investors, portfolio managers, and policymakers regarding their investment strategies, portfolio allocation, and risk monitoring.
•We focus on the connectedness between NFT, Defi coins, and financial assets.•We examine the return and volatility spillover effects between them.•Returns and volatility spillovers have been significantly affected by the COVID-19 pandemic.•The long- and short-term connectedness among the volatility of the assets vary over the course•Interdependencies between new digital and other financial assets intensified.
Recycling of spent lithium-ion batteries (LIBs) has attracted significant attention in recent years due to the increasing demand for corresponding critical metals/materials and growing pressure on ...the environmental impact of solid waste disposal. A range of investigations have been carried out for recycling spent LIBs to obtain either battery materials or individual compounds. For the effective recovery of materials to be enhanced, physical pretreatment is usually applied to obtain different streams of waste materials ensuring efficient separation for further processing. Subsequently, a metallurgical process is used to extract metals or separate impurities from a specific waste stream so that the recycled materials or compounds can be further prepared by incorporating principles of materials engineering. In this review, the current status of spent LIB recycling is summarized in light of the whole recycling process, especially focusing on the hydrometallurgy. In addition to understanding different hydrometallurgical technologies including acidic leaching, alkaline leaching, chemical precipitation, and solvent extraction, the existing challenges for process optimization during the recycling are critically analyzed. Moreover, the energy consumption of different processes is evaluated and discussed. It is expected that this research could provide a guideline for improving spent LIB recycling, and this topic can be further stimulated for industrial realization.
K-ion batteries (KIBs) are now drawing increasing research interest as an inexpensive alternative to Li-ion batteries (LIBs). However, due to the large size of K+, stable electrode materials capable ...of sustaining the repeated K+ intercalation/deintercalation cycles are extremely deficient especially if a satisfactory reversible capacity is expected. Herein, we demonstrated that the structural engineering of carbon into a hollow interconnected architecture, a shape similar to the neuron-cell network, promised high conceptual and technological potential for a high-performance KIB anode. Using melamine-formaldehyde resin as the starting material, we identify an interesting glass blowing effect of this polymeric precursor during its carbonization, which features a skeleton-softening process followed by its spontaneous hollowing. When used as a KIB anode, the carbon scaffold with interconnected hollow channels can ensure a resilient structure for a stable potassiation/depotassiation process and deliver an extraordinary capacity (340 mAh g–1 at 0.1 C) together with a superior cycling stability (no obvious fading over 150 cycles at 0.5 C).
•Bioaugmentation improves the psychrophilic anaerobic digestion performance.•Biogas production was enhanced by 2.8–4.2-fold.•T80 time was shortened by 11–22 d.•Bioaugmentation alleviates VFA ...accumulation, especially of acetate and propionate.•Bioaugmentation alters the microbial community structure.
Low temperatures result in poor anaerobic digestion (AD). To investigate whether bioaugmentation can improve anaerobic co-digestion of cattle manure and corn straw at 20 °C, five different doses of methanogenic propionate-degrading culture (4%, 8%, 12%, 14%, and 16%) were added to batch AD systems to compare bioaugmentation performance. The results showed that the methane production of all the bioaugmented digesters was enhanced compared to the control, increasing 2.80–4.20-fold with digestion times (T80) shorter by 11–22 d. The recommended dose for biogas production was 14%, and the recommended dose for the highest bioaugmentation efficiency of microbes was 4%. These improvements were due to the addition of methanogenic propionate-degrading culture, which alleviated volatile fatty acids (VFA) accumulation, especially that of acetate and propionate. Metagenomic sequencing analysis indicated that the increased proportion of propionate-oxidizing bacteria, syntrophic butyrate-oxidizing bacteria, and acetoclastic methanogens in bioaugmentation reactors may be responsible for better AD performance.
• Accumulation of reactive oxygen species (ROS) is a general plant basal defense strategy against viruses. In this study, we show that infection by Citrus tristeza virus (CTV) triggered ROS burst in ...Nicotiana benthamiana and in the natural citrus host, the extent of which was virus-dose dependent.
• Using Agrobacterium-mediated expression of CTV-encoded proteins in N. benthamiana, we found that p33, a unique viral protein, contributed to the induction of ROS accumulation and programmed cell death. The role of p33 in CTV pathogenicity was assessed based on gene knockout and complementation in N. benthamiana.
• In the citrus–CTV pathosystem, deletion of the p33 open reading frame in a CTV variant resulted in a significant determinantcrease in ROS production, compared to that of the wild type CTV, which correlated with invasion of the mutant virus into the immature xylem tracheid cells and abnormal differentiation of the vascular system. By contrast, the wild type CTV exhibited phloem-limited distribution with a minor effect on the vasculature.
• We conclude that the p33 protein is a CTV effector that negatively affects virus pathogenicity and suggest that N. benthamiana recognizes p33 to activate the host immune response to restrict CTV into the phloem tissue and minimize the disease syndrome.
Abiotic stresses lead to excessive crop yield losses and are a major threat to agriculture. It is essential to equip crops with multi-stress tolerance to mitigate the adverse effects of abiotic ...stressors and meet the demands of the increasing global population. The association between plants and symbiotic microorganisms is involved in key functions at the ecosystem and plant levels, and the application of microbial plant biostimulants (MPBs) is a sustainable strategy to augment plant growth and productivity, even under abiotic stress conditions. Several different microorganisms can be used as MPBs to enhance plant growth and produce progressive and reproducible effects on crops. In the present review, we assessed the current knowledge on the use of MPBs, discuss the diversity and characteristics of MPBs, and provide a meticulous assessment of the possible applications of MPBs in abiotic stress relief in crops.
Hollow carbon nanostructures have inspired numerous interests in areas such as energy conversion/storage, biomedicine, catalysis, and adsorption. Unfortunately, their synthesis mainly relies on ...template-based routes, which include tedious operating procedures and showed inadequate capability to build complex architectures. Here, by looking into the inner structure of single polymeric nanospheres, we identified the complicated compositional chemistry underneath their uniform shape, and confirmed that nanoparticles themselves stand for an effective and versatile synthetic platform for functional hollow carbon architectures. Using the formation of 3-aminophenol/formaldehyde resin as an example, we were able to tune its growth kinetics by controlling the molecular/environmental variables, forming resin nanospheres with designated styles of inner constitutional inhomogeneity. We confirmed that this intraparticle difference could be well exploited to create a large variety of hollow carbon architectures with desirable structural characters for their applications; for example, high-capacity anode for potassium-ion battery has been demonstrated with the multishelled hollow carbon nanospheres.
The mammalian target of rapamycin (mTOR) critically regulates several essential biological functions, such as cell growth, metabolism, survival, and immune response by forming two important ...complexes, namely, mTOR complex 1 (mTORC1) and complex 2 (mTORC2). mTOR signaling is often dysregulated in cancers and has been considered an attractive cancer therapeutic target. Great efforts have been made to develop efficacious mTOR inhibitors, particularly mTOR kinase inhibitors, which suppress mTORC1 and mTORC2; however, major success has not been achieved. With the strong scientific rationale, the intriguing question is why cancers are insensitive or not responsive to mTOR-targeted cancer therapy in clinics. Beyond early findings on induced activation of PI3K/Akt, MEK/ERK, and Mnk/eIF4E survival signaling pathways that compromise the efficacy of rapalog-based cancer therapy, recent findings on the essential role of GSK3 in mediating cancer cell response to mTOR inhibitors and mTORC1 inhibition-induced upregulation of PD-L1 in cancer cells may provide some explanations. These new findings may also offer us the opportunity to rationally utilize mTOR inhibitors in cancer therapy. Further elucidation of the biology of complicated mTOR networks may bring us the hope to develop effective therapeutic strategies with mTOR inhibitors against cancer.
Hemangioblasts give rise to endothelial progenitor cells (EPCs), which also express the cell surface markers CD133 and c-kit. They may differentiate into the outgrowth endothelial cells (OECs) that ...control neovascularization in the developing embryo. According to numerous studies, reduced levels of EPCs in circulation have been linked to human cardiovascular disorders. Furthermore, preeclampsia and senescence have been linked to levels of EPCs produced from cord blood. Uncertainties surround how preeclampsia affects the way EPCs function. It is reasonable to speculate that preeclampsia may have an impact on the function of fetal EPCs during the in utero period; however, the present literature suggests that maternal vasculopathies, including preeclampsia, damage fetal circulation. Additionally, the differentiation potential and general activity of EPCs may serve as an indicator of the health of the fetal vascular system as they promote neovascularization and repair during pregnancy. Thus, the purpose of this review is to compare-through the assessment of their quantity, differentiation potency, angiogenic activity, and senescence-the angiogenic function of fetal EPCs obtained from cord blood for normal and pregnancy problems (preeclampsia, gestational diabetes mellitus, and fetal growth restriction). This will shed light on the relationship between the angiogenic function of fetal EPCs and pregnancy complications, which could have an effect on the management of long-term health issues like metabolic and cardiovascular disorders in offspring with abnormal vasculature development.
Bones and articular cartilage are important load-bearing tissues. The fluid flow inside the bone cells and cell interaction with the extracellular matrix serve as the mechanical cues for bones and ...joints. Piezo1 is an ion channel found on the cell surface of many cell types, including osteocytes and chondrocytes. It is activated in response to mechanical stimulation, which subsequently mediates a variety of signaling pathways in osteoblasts, osteocytes, and chondrocytes. Piezo1 activation in osteoblastic cells positively regulates osteogenesis, while its activation in joints mediates cartilage degradation. This review focuses on the most recent research on Piezo1 in bone development and regeneration.
•Piezo1 exists on the cell surface including osteocytes, osteoblasts, bone marrow mesenchymal stem cells and chondrocytes.•Piezo1 is crucial for bone formation and angiogenesis within the bone microenvironment.•Piezo1 could be a potential treatment target for correcting bone defects during embryogenesis and skeletal development.
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