Atomically Dispersed Mo Supported on Metallic Co9S8 Nanoflakes as an Advanced Noble‐Metal‐Free Bifunctional Water Splitting Catalyst Working in Universal pH Conditions

Water splitting requires development of cost‐effective multifunctional materials that can catalyze both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) efficiently. Currently, the OER relies on the noble‐metal catalysts; since with other catalysts, its operation environment is greatly limited in alkaline conditions. Herein, an advanced water oxidation catalyst based on metallic Co₉S₈ decorated with single‐atomic Mo (0.99 wt%) is synthesized (Mo‐Co₉S₈@C). It exhibits pronounced water oxidization activity in acid, alkali, and neutral media by showing positive onset potentials of 200, 90, and 290 mV, respectively, which manifests the best Co₉S₈‐based single‐atom Mo catalyst till now. Moreover, it also demonstrates excellent HER performance over a wide pH range. Consequently, the catalyst even outperforms noble metal Pt/IrO₂‐based catalysts for overall water splitting (only requiring 1.68 V in acid, and 1.56 V in alkaline). Impressively, it works under a current density of 10 mA cm^?2 with no obvious decay during a 24 h (0.5 m H₂SO₄) and 72 h (1.0 m KOH) durability experiment. Density functional theory (DFT) simulations reveal that the synergistic effects of atomically dispersed Mo with Co‐containing substrates can efficiently alter the binding energies of adsorbed intermediate species and decrease the overpotentials of the water splitting.     

Boosting Superior Lithium Storage Performance of Alloy‐Based Anode Materials via Ultraconformal Sb Coating–Derived Favorable Solid‐Electrolyte Interphase

Alloy materials such as Si and Ge are attractive as high‐capacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during discharge–charge processes. Compared to the over‐emphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solid‐electrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloy‐based anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li₃Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiF‐dominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sb‐coated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh g^?1 after 200 cycles at 500 mA g^?1, compared to only 72% and 170 mAh g^?1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve long‐term cycling stability for alloy‐based anode materials.     

Toward a Reversible Mn4+/Mn2+ Redox Reaction and Dendrite‐Free Zn Anode in Near‐Neutral Aqueous Zn/MnO2 Batteries via Salt Anion Chemistry

Rechargeable aqueous Zn/MnO₂ batteries are very attractive large‐scale energy storage technologies, but still suffer from limited cycle life and low capacity. Here the novel adoption of a near‐neutral acetate‐based electrolyte (pH ≈ 6) is presented to promote the two‐electron Mn⁴⁺/Mn²⁺ redox reaction and simultaneously enable a stable Zn anode. The acetate anion triggers a highly reversible MnO₂/Mn²⁺ reaction, which ensures high capacity and avoids the issue of structural collapse of MnO₂. Meanwhile, the anode‐friendly electrolyte enables a dendrite‐free Zn anode with outstanding stability and high plating/stripping Coulombic efficiency (99.8%). Hence, a high capacity of 556 mA h g^?1, a lifetime of 4000 cycles without decay, and excellent rate capability up to 70 mA cm^?2 are demonstated in this new near‐neutral aqueous Zn/MnO₂ battery by simply manipulating the salt anion in the electrolyte. The acetate anion not only modifies the surface properties of MnO₂ cathode but also creates a highly compatible environment for the Zn anode. This work provides a new opportunity for developing high‐performance Zn/MnO₂ and other aqueous batteries based on the salt anion chemistry.     

Double the Capacity of Manganese Spinel for Lithium‐Ion Storage by Suppression of Cooperative Jahn–Teller Distortion

The relatively low capacity and capacity fade of spinel LiMn₂O₄ (LMO) limit its application as a cathode material for lithium‐ion batteries. Extending the potential window of LMO below 3 V to access double capacity would be fantastic but hard to be realized, as it will lead to fast capacity loss due to the serious Jahn–Teller distortion. Here using experiments combined with extensive ab initio calculations, it is proved that there is a cooperative effect among individual Jahn–Teller distortions of Mn³⁺O₆ octahedrons in LMO, named as cooperative Jahn–Teller distortion (CJTD) in the text, which is the difficulty to access the capacity beyond one lithium intercalation. It is further proposed that the cationic disordering (excess Li at Mn sites and Li/Mn exchange) can intrinsically suppress the CJTD of Mn³⁺O₆ octahedrons. The cationic disordering can break the symmetry of Mn³⁺ arrangements to disrupt the correlation of distortions arising from individual JT centers and prevent the Mn³⁺? O bonds distorting along one direction. Interestingly, with the suppressed CJTD, the original octahedral vacancies in spinel LMO are activated and can serve as extra Li‐ion storage sites to access the double capacity with good reversible cycling stability in microsized LMO.     

Long Term Culture of Human Kidney Proximal Tubule Epithelial Cells Maintains Lineage Functions and Serves as an Ex vivo Model for Coronavirus Associated Kidney Injury

The mechanism of how SARS-CoV-2 causes severe multi-organ failure is largely unknown. Acute kidney injury(AKI) is one of the frequent organ damage in severe COVID-19 patients. Previous studies have shown that human renal tubule cells could be the potential host cells targeted by SARS-CoV-2. Traditional cancer cell lines or immortalized cell lines are genetically and phenotypically different from host cells. Animal models are widely used, but often fail to reflect a physiological and pathogenic status because of species tropisms. There is an unmet need for normal human epithelial cells for disease modeling. In this study, we successfully established long term cultures of normal human kidney proximal tubule epithelial cells(KPTECs) in 2 D and 3 D culture systems using conditional reprogramming(CR) and organoids techniques.These cells had the ability to differentiate and repair DNA damage, and showed no transforming property. Importantly, the CR KPTECs maintained lineage function with expression of specific transporters(SLC34 A3 and cubilin). They also expressed angiotensin-converting enzyme 2(ACE2), a receptor for SARS-CoV and SARS-CoV-2. In contrast, cancer cell line did not express endogenous SLC34 A3, cubilin and ACE2. Very interestingly, ACE2 expression was around twofold higher in 3 D organoids culture compared to that in 2 D CR culture condition. Pseudovirion assays demonstrated that SARS-CoV spike(S) protein was able to enter CR cells with luciferase reporter. This integrated 2 D CR and 3 D organoid cultures provide a physiological ex vivo model to study kidney functions, innate immune response of kidney cells to viruses, and a novel platform for drug discovery and safety evaluation.     

Correction to: Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

Virologica Sinica - The corrected legend is given below.     

DNA framework-engineered electrochemical biosensors

Self-assembled DNA nanostructures have shown remarkable potential in the engineering of biosensing interfaces, which can improve the performance of various biosensors. In particular, by exploiting the structural rigidity and programmability of the framework nucleic acids with high precision, molecular recognition on the electrochemical biosensing interface has been significantly enhanced, leading to the development of highly sensitive and specific biosensors for nucleic acids, small molecules,proteins, and cells. In this review, we summarize recent advances in DNA framework-engineered biosensing interfaces and the application of corresponding electrochemical biosensors.     

RELMα可通过抑制PTEN信号通路来促进气道重塑并增加炎症反应

本研究旨在考察抵抗素样分子-α(resistin-like molecule-α,RELMα)在哮喘小鼠模型和小鼠肺上皮细胞中的表达及对气道重塑和炎症反应的影响。本研究通过卵清蛋白(ovalbumin,OVA)诱导小鼠哮喘模型,并评估了小鼠肺组织中RELMα、collagen I和fibronectin-1的表达。为了研究RELMα对PTEN信号通路的调控作用,本研究利用shRNA-RELMα、pcDNA3.0-RELMα和pcDNA3.0-PTEN转染小鼠肺上皮细胞系TC-1来上调或下调RELMα及PTEN的表达。通过Western blotting检测了TC-1细胞中RELMα、collagenⅠ、fibronectin-1、PTEN、TNF-α、IL-1β和IL-6的表达。研究发现,与对照小鼠相比,OVA致敏的哮喘小鼠的肺组织中RELMα、collagen I和fibronectin-1的表达显著升高。上调RELMα可显著升高collagenⅠ、fibronectin-1、TNF-α、IL-1β和IL-6的表达并抑制PTEN信号通路的活化。上调PTEN则可抑制collagenⅠ、fibronectin-1、TNF-α、IL-1β和IL-6的表达。本研究表明,RELMα在哮喘发病过程中高表达,上调RELMα可抑制PTEN信号通路来促进气道重塑并增加炎症反应。     

The use of SARS-CoV-2-related coronaviruses from bats and pangolins to polarize mutations in SARS-Cov-2

正Dear Editor,The coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 coronavirus has become a global pandemic.The SARS-CoV-2 genome has a similarity of 96.2%to that of RaTG13, a bat SARS-CoV-2-related coronavirus detected in Rhinolophus affinis (Paraskevis et al., 2020; Zhou et al.,2020). The SARS-CoV-2 genome also has 85.5%-92.4%