Although silicon is a promising anode material for lithium-ion batteries, scalable synthesis of silicon anodes with good cyclability and low electrode swelling remains a significant challenge. ...Herein, we report a scalable top-down technique to produce ant-nest-like porous silicon from magnesium-silicon alloy. The ant-nest-like porous silicon comprising three-dimensional interconnected silicon nanoligaments and bicontinuous nanopores can prevent pulverization and accommodate volume expansion during cycling resulting in negligible particle-level outward expansion. The carbon-coated porous silicon anode delivers a high capacity of 1,271 mAh g
at 2,100 mA g
with 90% capacity retention after 1,000 cycles and has a low electrode swelling of 17.8% at a high areal capacity of 5.1 mAh cm
. The full cell with the prelithiated silicon anode and Li(Ni
Co
Mn
)O
cathode boasts a high energy density of 502 Wh Kg
and 84% capacity retention after 400 cycles. This work provides insights into the rational design of alloy anodes for high-energy batteries.
Their pervasive use in industrial applications renders the development of environmentally benign flame-retardant epoxy (EP) thermosets a timely and important goal. The last two decades have witnessed ...the rise of phosphorus (P)-containing flame retardants for EP due to their high flame retardancy efficiency, low toxicity, multiple modes of action, molecular diversity and other favorable properties. P-containing flame retardants are classified into two types: reactive and additive, according to whether they participate in the curing process. Recent advances in both of these classes of P-containing flame retardants motivate this comprehensive review on the design and synthesis of P-containing flame retardants and their impact on the material properties of EP thermosets. This review focuses on the state-of-the-art knowledge of P-containing flame retardants and their effects on flame retardancy, thermal stability and mechanical properties of the resultant EP. First, representative flame-retardant mechanisms are reviewed. Subsequently, practical applications of P-containing flame-retardant EP thermosets are presented. Finally, the key challenges associated with P-containing flame retardants for EP thermosets are highlighted, and opportunities for future research in the field are proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Aims
Conventional fractional flow reserve (FFR) is measured invasively using a coronary guidewire equipped with a pressure sensor. A non-invasive derived FFR would eliminate risk of coronary ...injury, minimize technical limitations, and potentially increase adoption. We aimed to evaluate the diagnostic performance of a computational pressure-flow dynamics derived FFR (caFFR), applied to coronary angiography, compared to invasive FFR.
Methods and results
The FLASH FFR study was a prospective, multicentre, single-arm study conducted at six centres in China. Eligible patients had native coronary artery target lesions with visually estimated diameter stenosis of 30–90% and diagnosis of stable or unstable angina pectoris. Using computational pressure-fluid dynamics, in conjunction with thrombolysis in myocardial infarction (TIMI) frame count, applied to coronary angiography, caFFR was measured online in real-time and compared blind to conventional invasive FFR by an independent core laboratory. The primary endpoint was the agreement between caFFR and FFR, with a pre-specified performance goal of 84%. Between June and December 2018, matched caFFR and FFR measurements were performed in 328 coronary arteries. Total operational time for caFFR was 4.54 ± 1.48 min. caFFR was highly correlated to FFR (R = 0.89, P = 0.76) with a mean bias of −0.002 ± 0.049 (95% limits of agreement −0.098 to 0.093). The diagnostic performance of caFFR vs. FFR was diagnostic accuracy 95.7%, sensitivity 90.4%, specificity 98.6%, positive predictive value 97.2%, negative predictive value 95.0%, and area under the receiver operating characteristic curve of 0.979.
Conclusions
Using wire-based FFR as the reference, caFFR has high accuracy, sensitivity, and specificity. caFFR could eliminate the need of a pressure wire, technical error and potentially increase adoption of physiological assessment of coronary artery stenosis severity.
Clinical Trial Registration
URL: http://www.chictr.org.cn Unique Identifier: ChiCTR1800019522.
Abstract
Gene set enrichment (GSE) analysis plays an essential role in extracting biological insight from genome-scale experiments. ORA (overrepresentation analysis), FCS (functional class scoring), ...and PT (pathway topology) approaches are three generations of GSE methods along the timeline of development. Previous versions of KOBAS provided services based on just the ORA method. Here we presented version 3.0 of KOBAS, which is named KOBAS-i (short for KOBAS intelligent version). It introduced a novel machine learning-based method we published earlier, CGPS, which incorporates seven FCS tools and two PT tools into a single ensemble score and intelligently prioritizes the relevant biological pathways. In addition, KOBAS has expanded the downstream exploratory visualization for selecting and understanding the enriched results. The tool constructs a novel view of cirFunMap, which presents different enriched terms and their correlations in a landscape. Finally, based on the previous version's framework, KOBAS increased the number of supported species from 1327 to 5944. For an easier local run, it also provides a prebuilt Docker image that requires no installation, as a supplementary to the source code version. KOBAS can be freely accessed at http://kobas.cbi.pku.edu.cn, and a mirror site is available at http://bioinfo.org/kobas.
Graphical Abstract
Graphical Abstract
Framework of KOBAS.
Countries have sought to stop the spread of coronavirus disease 2019 (COVID-19) by severely restricting travel and in-person commercial activities. Here, we analyse the supply-chain effects of a set ...of idealized lockdown scenarios, using the latest global trade modelling framework. We find that supply-chain losses that are related to initial COVID-19 lockdowns are largely dependent on the number of countries imposing restrictions and that losses are more sensitive to the duration of a lockdown than its strictness. However, a longer containment that can eradicate the disease imposes a smaller loss than shorter ones. Earlier, stricter and shorter lockdowns can minimize overall losses. A 'go-slow' approach to lifting restrictions may reduce overall damages if it avoids the need for further lockdowns. Regardless of the strategy, the complexity of global supply chains will magnify losses beyond the direct effects of COVID-19. Thus, pandemic control is a public good that requires collective efforts and support to lower-capacity countries.
Covalent organic frameworks (COFs) are generally obtained as insoluble, cross-linked powders or films, hindering their superior processable properties especially for device implementation. Here, a ...soluble COF is created with atomically well-organized positive charged centers constrained in the planar direction, exhibiting exceptional solubility through an in situ charge exfoliation pathway. Once dissolved, the obtained true solution retains homogeneity even after standing over a year. Moreover, the as-designed soluble COF contains ordered N-coordinated Fe single atom centers and conjugated structures, providing a small work function (4.84 eV) and superior catalytic performance for oxygen reduction (high half-wave potential of ∼900 mV). The obtained COF true solution can be directly used as a highly efficient Pt-replaced catalyst for zinc–air flow batteries, generating prominent performance and outstanding stability.
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IJS, KILJ, NUK, PNG, UL, UM
The main pathological mechanism of intervertebral disc degeneration (IVDD) is the programmed apoptosis of nucleus pulposus (NP) cells. Oxidative stress is a significant cause of IVDD. Whether ...mitophagy is induced by strong oxidative stress in IVDD remains to be determined. This study aimed to investigate the relationship between oxidative stress and mitophagy and to better understand the mechanism of IVDD in vivo and in vitro. To this end, we obtained primary NP cells from the human NP and subsequently exposed them to TBHP. We observed that oxidative stress induced mitophagy to cause apoptosis in NP cells, and we suppressed mitophagy and found that NP cells were protected against apoptosis. Interestingly, TBHP resulted in mitophagy through the inhibition of the HIF-1α/NDUFA4L2 pathway. Therefore, the upregulation of mitochondrial NDUFA4L2 restricted mitophagy induced by oxidative stress. Furthermore, the expression levels of HIF-1α and NDUFA4L2 were decreased in human IVDD. In conclusion, these results demonstrated that the upregulation of NDUFA4L2 ameliorated the apoptosis of NP cells by repressing excessive mitophagy, which ultimately alleviated IVDD. These findings show for the first time that NDUFA4L2 and mitophagy may be potential therapeutic targets for IVDD.
The present study investigated gender differences in both emotional experience and expressivity. Heart rate (HR) was recorded as an indicator of emotional experience while the participants watched 16 ...video clips that induced eight types of emotion (sadness, anger, horror, disgust, neutrality, amusement, surprise, and pleasure). We also asked the participants to report valence, arousal, and motivation as indicators of emotional expressivity. Overall, the results revealed gender differences in emotional experience and emotional expressivity. When watching videos that induced anger, amusement, and pleasure, men showed larger decreases in HR, whereas women reported higher levels of arousal. There was no gender difference in HR when the participants watched videos that induced horror and disgust, but women reported lower valence, higher arousal, and stronger avoidance motivation than did men. Finally, no gender difference was observed in sadness or surprise, although there was one exception-women reported higher arousal when watching videos that induced sadness. The findings suggest that, when watching videos that induce an emotional response, men often have more intense emotional experiences, whereas women have higher emotional expressivity, particularly for negative emotions. In addition, gender differences depend on the specific emotion type but not the valence.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Two-dimensional (2D) antimonene is a promising anode material in sodium-ion batteries (SIBs) because of its high theoretical capacity of 660 mAh g–1 and enlarged surface active sites. However, its Na ...storage properties and sodiation/desodiation mechanism have not been fully explored. Herein, we propose the sodiation/desodiation reaction mechanism of 2D few-layer antimonene (FLA) based on results acquired by in situ synchrotron X-ray diffraction, ex situ selected-area electron diffraction, and theoretical simulations. Our study shows that the FLA undergoes anisotropic volume expansion along the a/b plane and exhibits reversible crystalline phase evolution (Sb ⇋ NaSb ⇋ Na3Sb) during cycling. Density-functional theory calculations demonstrate that the FLA has a small Na-ion diffusion barrier of 0.14 eV. The FLA delivers a larger capacity of 642 mAh g–1 at 0.1 C (1 C = 660 mA g–1) and a high rate capability of 429 mAh g–1 at 5 C and maintains a stable capacity of 620 mA g–1 at 0.5 C with 99.7% capacity retention from the 10th to the 150th cycle. Considering the 660 mAh g–1 theoretical capacity of Sb, the electrochemical utilization of Sb atoms of FLA is as high as 93.9% at a rate of 0.5 C for over 150 cycles, which is the highest capacity and Sb utilization ratio reported so far. Our study discloses the Na storage mechanism of 2D FLA, boosting promising applications of 2D materials for advanced SIBs.
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IJS, KILJ, NUK, PNG, UL, UM
Monochromatic light can be characterized by its three fundamental properties: amplitude, phase, and polarization. In this work, we propose a versatile, transmission-mode all-dielectric metasurface ...platform that can independently manipulate the phase and amplitude for two orthogonal states of polarization in the visible frequency range. For proof-of-concept experimental demonstration, various single-layer metasurfaces composed of subwavelength-spaced titanium-dioxide nanopillars are designed, fabricated, and characterized to exhibit the ability of polarization-switchable multidimensional light-field manipulation, including polarization-switchable grayscale nanoprinting, nonuniform cylindrical lensing, and complex-amplitude holography. We envision the metasurface platform demonstrated here to open new possibilities toward creating compact multifunctional optical devices for applications in polarization optics, information encoding, optical data storage, and security.
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