•Analyze risk spillovers between cryptocurrencies and traditional currencies/gold.•A Diagonal BEKK model is developed for data analysis.•Compare the patterns of risk spillovers under different global ...economic conditions.•Risk spillovers are significantly different between normal and extreme markets.•Cryptocurrencies can be considered as safe havens during COVID-19.
This paper applies a Diagonal BEKK model to investigate the risk spillovers of three major cryptocurrencies to ten leading traditional currencies and two gold prices (Spot Gold and Gold Futures). The daily data used are from 7 August 2015 to 15 June 2020. The dataset is analyzed in its entirety and is also subdivided into four distinct subsets in order to study and compare the patterns of spillover effects during economic turmoil, such as the 2018 cryptocurrency crash and the COVID-19 pandemic. The results reveal significant co-volatility spillover effects between cryptocurrency and traditional currency or gold markets, especially during the whole sample period and amid the uncertainty raised by COVID-19. The capabilities of cryptocurrency are time-varying and related to economic uncertainty or shocks. There are significant differences between normal and extreme markets with regard to the capabilities of cryptocurrency as a diversifier, a hedge or a safe haven. We find the significant co-volatility spillover effects are asymmetric in most cases especially during the COVID-19 pandemic period, which means the negative return shocks have larger impacts on co-volatility than positive return shocks of the same magnitude. Evidently, cryptocurrencies and traditional currencies or gold can be incorporated into financial portfolios for financial market participants who seek effective risk management and also for optimal dynamic hedging purposes against economic turmoil and downward movements.
To explore the interior of a lesion in a 3D endoluminal view, this study investigates the application of an 'electronic biopsy' (EB) technique to computed tomographic colonography (CTC) for further ...differentiation and 2D image correlation of endoluminal lesions in the air spaces. A retrospective study of sixty-two various endoluminal lesions from thirty patients (13 males, 17 females; age range, 31 to 90 years) was approved by our institutional review board and evaluated. The endoluminal lesions were segmented using gray-level threshold and reconstructed into isosurfaces using a marching cube algorithm. EB allows users to interactively erode and apply grey-level mapping (GM) to the surface of the region of interest (ROI) in 3D CTC. Radiologists conducted the clinical evaluation, and the resulting data were analyzed. EB significantly improves 3D gray-level presentation for evaluating the surface and inside of endoluminal lesions over that of SR, GM or target GM (TGM) (P < 0.01) with preservation of the 3D spatial effect. Moreover, 3D to 2D image correlation were achieved in any layer of the lesion using EB as did GM/TGM on the surface. The specificity and diagnostic accuracy of EB are significantly greater than those of SR (P < 0.01). These performance can be better further with GM/TGM and reach the best with EB (specificity, 89.3-92.9%; accuracy, 95.2-96.8%). EB can be used in CTC to improve the differentiation of endoluminal lesions. EB increases 3D to 2D image correlations of the lesions on or beneath the lesion surface.
This paper examines and confirms the varying volatility of the relationship between cryptocurrency and currency markets at different time periods, such as when the market encountered multiple risk ...events including the US-China trade war, COVID-19, and the Russian-Ukraine war. We employ the Diagonal BEKK model and find that the co-volatility spillover effects between the returns of cryptocurrencies and currencies, with the exception of Tether and the U.S. dollar index, evolved significantly. Furthermore, the co-volatility spillover effects between cryptocurrencies and EUR have the largest effects and fluctuations. Large-cap cryptocurrencies (Bitcoin and Ethereum) have greater co-volatility spillover effects between them and currencies. Regarding the ability of cryptocurrencies to act as safe-haven for currencies, we observe that Bitcoin, Ethereum, and Tether served as safe-havens during the US-China trade war, and Bitcoin was a safe-haven during COVID-19. During the 2022 Russian-Ukraine war, Bitcoin and Tether were safe-havens. Interestingly, our findings point out that Bitcoin provides a more consistent safe-haven function for currency markets. Overall, by including multiple global risk events and a comprehensive dataset, the results support our conjecture (and earlier studies) indicating that the capabilities of cryptocurrency are time-varying and related to market status and risk events with different natures.
We previously demonstrated that metabolic switch and mitochondrial activation are required for osteogenic differentiation of human mesenchymal stem cells (hMSCs). However, stem cells in niches or ...transplanted into injured tissues constantly encounter hypoxic stress that hinders aerobic metabolism. Therefore, we investigated the effects of oxygen tension (1% vs. 21%) on metabolism and osteogenic differentiation of hMSCs. We found that hypoxia impaired osteogenic differentiation as indicated by attenuation of alkaline phosphatase activity and expression of osteogenic markers core binding factor a-1 and osteopontin. In addition, differentiation-induced mitochondrial activation was compromised as shown by the decrease in the expression of respiratory enzymes and oxygen consumption rate. On the contrary, anaerobic metabolism was augmented as revealed by the upregulation of glycolytic enzymes and increase of lactate production, rendering the cells to rely more on anaerobic glycolysis for energy supply. Moreover, administration of 2-deoxyglucose (a glycolytic inhibitor) but not antimycin A (a respiratory inhibitor) significantly decreased intracellular ATP levels of hMSCs differentiating under hypoxia. Treatment with cobalt chloride, a hypoxia-inducible factor-1α (HIF-1α) stabilizer, recapitulated the inhibitory effects of hypoxia, suggesting that HIF-1α is involved in the compromise of hMSCs differentiation. These results suggest that hypoxia inhibits metabolic switch and mitochondrial function and therefore suppresses osteogenic differentiation of hMSCs.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in countless infections and caused millions of deaths since its emergence in 2019. Coronavirus disease 2019 ...(COVID-19)-associated mortality is caused by uncontrolled inflammation, aberrant immune response, cytokine storm, and an imbalanced hyperactive immune system. The cytokine storm further results in multiple organ failure and lung immunopathology. Therefore, any potential treatments should focus on the direct elimination of viral particles, prevention strategies, and mitigation of the imbalanced (hyperactive) immune system. This review focuses on cytokine secretions of innate and adaptive immune responses against COVID-19, including interleukins, interferons, tumor necrosis factor-alpha, and other chemokines. In addition to the review focus, we discuss potential immunotherapeutic approaches based on relevant pathophysiological features, the systemic immune response against SARS-CoV-2, and data from recent clinical trials and experiments on the COVID-19-associated cytokine storm. Prompt use of these cytokines as diagnostic markers and aggressive prevention and management of the cytokine storm can help determine COVID-19-associated morbidity and mortality. The prophylaxis and rapid management of the cytokine storm appear to significantly improve disease outcomes. For these reasons, this study aims to provide advanced information to facilitate innovative strategies to survive in the COVID-19 pandemic.
In this study, different probiotics commonly used to produce fermented dairy products were inoculated independently for Chenopodium formosanum Koidz. fermentation. The strain with the highest level ...of antioxidant activity was selected and the fermentation process was further optimized via response surface methodology (RSM). Lactobacillus plantarum BCRC 11697 was chosen because, compared to other lactic acid bacteria, it exhibits increased free radical scavenging ability and can produce more phenolic compounds, DPPH (from 72.6% to 93.2%), and ABTS (from 64.2% to 76.9%). Using RSM, we further optimize the fermentation protocol of BCRC 11697 by adjusting the initial fermentation pH, agitation speed, and temperature to reach the highest level of antioxidant activity (73.5% of DPPH and 93.8% of ABTS). The optimal protocol (pH 5.55, 104 rpm, and 24.4°C) resulted in a significant increase in the amount of phenolic compounds as well as the DPPH and ABTS free radical scavenging ability of BCRC 11697 products. The IC50 of the DPPH and ABTS free radical scavenging ability were 0.33 and 2.35 mg/mL, respectively, and both protease and tannase activity increased after RSM. An increase in lower molecular weight (<24 kDa) protein hydrolysates was also observed. Results indicated that djulis fermented by L. plantarum can be a powerful source of natural antioxidants for preventing free radical-initiated diseases.
Horizontally stacked pure-Ge-nanosheet gate-all-around field-effect transistors (GAA FETs) were developed in this study. Large lattice mismatch Ge/Si multilayers were intentionally grown as the ...starting material rather than Ge/GeSi multilayers to acquire the benefits of the considerable difference in material properties of Ge and Si for realising selective etching. Flat Ge/Si multilayers were grown at a low temperature to preclude island growth. The shape of Ge nanosheets was almost retained after etching owing to the excellent selectivity. Additionally, dislocations were observed in suspended Ge nanosheets because of the absence of a Ge/Si interface and the disappearance of the dislocation-line tension force owing to the elongation of misfit dislocation at the interface. Forming gas annealing of the suspended Ge nanosheets resulted in a significant increase in the glide force compared to the dislocation-line tension force; the dislocations were easily removed because of this condition and the small size of the nanosheets. Based on this structure, a new mechanism of dislocation removal from suspended Ge nanosheet structures by annealing was described, which resulted in the structures exhibiting excellent gate control and electrical properties.
Scope
Particulate matter (PM) contains toxic organic matter and heavy metals that enter the entire body through blood flow and may cause mortality. Ganoderma formosanum mycelium, a valuable ...traditional Chinese medicine that has been used since ancient times, contains various active ingredients that can effectively impede inflammatory responses on murine alveolar macrophages induced by PM particles.
Methods and Results
An experimental study assessing the effect of G. formosanum mycelium extract's water fraction (WA) on PM‐exposed murine alveolar macrophages using ROS measurement shows that WA reduces intracellular ROS by 12% and increases cell viability by 16% when induced by PM particles. According to RNA‐Sequencing, western blotting, and real‐time qPCR are conducted to analyze the metabolic pathway. The WA reduces the protein ratio in p‐NF‐κB/NF‐κB by 18% and decreases the expression of inflammatory genes, including IL‐1β by 38%, IL‐6 by 29%, and TNF‐α by 19%. Finally, the identification of seven types of anti‐inflammatory compounds in the WA fraction is achieved through UHPLC‐ESI‐Orbitrap‐Elite‐MS/MS analysis. These compounds include anti‐inflammatory compounds, namely thiamine, adenosine 5ʹ‐monophosphate, pipecolic acid, L‐pyroglutamic acid, acetyl‐L‐carnitine, D‐mannitol, and L‐malic acid.
Conclusions
The study suggests that the WA has the potential to alleviate the PM ‐induced damage in alveolar macrophages, demonstrating its anti‐inflammatory properties.
GFE water extraction attenuate PM‐induced cell inflammation.
Compression behavior of nanoparticle powder is still unclear, while it could largely affect its applications in additive manufacturing. Considering the fractal structure of aggregates in nanoparticle ...powder, from the van der Waal's state equation, the relation between porosity and compression pressure of nanoparticle powder was modeled theoretically, i.e. (P + c)(φ-a)=(1-a)c, here P is pressure, φ is porosity, a and c are parameters defined in main text. The model could capture the compression behavior of nanoparticle powders well. Under the same compression pressure, smaller nanoparticles will lead to larger porosity and thus lower thermal conductivity of nanoparticle packed beds, due to the easier aggregate of smaller nanoparticles. The compression behavior and the thermal conductivity of nanoparticle powders or packed beds are expected to supply information for powder spreading and sintering treatment respectively in additive manufacturing.
This study estimates the amplitude saturation process of spontaneous pressure oscillations in the thermoacoustic Stirling engine, which harnesses a stack-screen regenerator, after the engine onset. ...To observe spontaneous initiations leading to finite amplitudes of sound in the engine, the engine is studied experimentally to see how the acoustic pressure fluctuates in the time domain. To describe this, the nonlinear effects of the flow resistance of the stacked-screen regenerators, empirically proposed as an effective radius reff whose size decreases with increasing Reynolds number, are incorporated into the framework of Rott’s linear thermoacoustic theory for depicting the evolution of oscillations from initiation to a steady state. The numerical calculations are based on the coupling between pressure oscillations and the imaginary part of a complex angular frequency which is obtained numerically from the characteristic equation derived from the transfer matrices modeling the engine. For the scenarios of steady oscillations, the measured results are elucidated with calculations by consciously adjusting r0 which is involved in reff and estimates the threshold of thermoacoustic instability. By plotting with the adjusted r0, the measured stability limits expressly agree with the stability curve calculated from Rott’s theory. This work improves Rott’s frequency-domain theory to the temporal description of the thermoacoustic Stirling engine, from start-up to limit cycle oscillation.
•This study estimates amplitude saturation of pressure oscillations in a thermoacoustic Stirling engine.•We enhance the description of temporal oscillations by integrating non-linear dissipations of the stacked-screen regenerator into Rott’s frequency-domain theory, achieved by coupling pressure oscillation with ωI.•Observations are clarified using calculations by fine-tuning r0, crucial for estimating engine initiation.
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