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The cathode materials work as the host framework for both Li+ diffusion and electron transport in Li-ion batteries. The Li+ diffusion property is always the research focus, while the electron transport property is less studied. Herein, we propose a unique strategy to elevate the rate performance through promoting the surface electric conductivity. Specifically, a disordered rock-salt phase was coherently constructed at the surface of LiCoO2, promoting the surface electric conductivity by over one magnitude. It increased the effective voltage (Veff) imposed in the bulk, thus driving more Li+ extraction/insertion and making LiCoO2exhibit superior rate capability (154 mA h g-1 at 10 C), and excellent cycling performance (93% after 1000 cycles at 10 C). The universality of this strategy was confirmed by another surface design and a simulation. Our findings provide a new angle for developing high-rate cathode materials by tuning the surface electron transport property.

Oxygen deficiencies are well recognized to have a detrimental effect on the performance of spinel LiMn2O4-δ as the cathode for non-aqueous systems, whereas the influences have not been explored for aqueous systems yet. Here, we successfully introduce oxygen deficiencies into LiMn2O4-δ by calcination of oxygen deficiency-free LiMn2O4 at 850 °C for 2 h followed by quenching in air. LiMn2O4-δ primary particles show the octahedral shape, the sizes of about 400 nm, and the larger lattice constant of 8.240 A, in contrast with the irregular shapes, the sizes of about 100 nm, and the lattice constant of 8.231 A. In the non-aqueous system, the performances for LiMn2O4-δ are inferior compared to LiMn2O4, as reported previously. However, both LiMn2O4-δ||polyimide and LiMn2O4||polyimide aqueous full cells exhibit the discharge capacity of about 105 mAh g−1 at 100 mA g−1 and the capacity retentions of 87% and 60% after 100 cycles. The plateau of H2O decomposition observed at about 1.85 V for LiMn2O4 leads to much poorer performance which is absent for LiMn2O4-δ. This study demonstrates different requirements by the cathodes in the non-aqueous and aqueous systems and offers a new idea for improving the performance and stability of the electrodes for aqueous cells.

Achievement of carbon materials with particular structures, dimensions, and sizes derived from metal organic frameworks (MOFs) with particular morphologies is very crucial for purpose-oriented appl...

To investigate the dynamic changes of Krebs von den Lungen‐6 (KL‐6) among patients with coronavirus disease 2019 (COVID‐19) and the role of KL‐6 as a noninvasive biomarker for predicting long‐term lung injury, the clinical information and laboratory tests of 166 COVID‐19 patients were collected, and a correlation analysis between KL‐6 and other parameters was conducted. There were 17 (10.2%, 17/166) severe/critical and 149 (89.8%, 149/166) mild COVID‐19 patients in our cohort. Serum KL‐6 was significantly higher in severe/critical COVID‐19 patients than in mild patients (median 898.0 vs. 451.2 U/ml, p 100 days postonset) was well correlated to those concentrations within 10 days postonset (Pearson r = .867, p, Highlights KL‐6 is a biomarker for assessing COVID‐19 severityKL‐6 predicts the prognosis of COVID‐19 patientsKL‐6 is associated with CT lung lesions areas.

Commercialized lithium cobalt oxide (LCO) only shows a relatively low capacity of ≈175 mAh g

Low-cost Mn- and Li-rich layered oxides suffer from rapid voltage decay, which can be improved by increasing the nickel content to derive high nickel Li-rich layered oxides (HNLO) but is normally accompanied by reduced capacity and inferior cycling stability. Herein, Na or K ions are successfully doped into the lattice of high nickel Li-rich Li

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been redetected after discharge in some coronavirus disease 2019 (COVID-19) patients. The reason for the recurrent positivity of the test and the potential public health concern due to this occurrence are still unknown. Here, we analyzed the viral data and clinical manifestations of 289 domestic Chinese COVID-19 patients and found that 21 individuals (7.3%) were readmitted for hospitalization after detection of SARS-CoV-2 after discharge. First, we experimentally confirmed that the virus was involved in the initial infection and was not a secondary infection. In positive retests, the virus was usually found in anal samples (15 of 21, 71.4%). Through analysis of the intracellular viral subgenomic messenger RNA (sgmRNA), we verified that positive retest patients had active viral replication in their gastrointestinal tracts (3 of 16 patients, 18.7%) but not in their respiratory tracts. Then, we found that viral persistence was not associated with high viral titers, delayed viral clearance, old age, or more severe clinical symptoms during the first hospitalization. In contrast, viral rebound was associated with significantly lower levels of and slower generation of viral receptor-binding domain (RBD)-specific IgA and IgG antibodies. Our study demonstrated that the positive retest patients failed to create a robust protective humoral immune response, which might result in SARS-CoV-2 persistence in the gastrointestinal tract and possibly in active viral shedding. Further exploration of the mechanism underlying the rebound in SARS-CoV-2 in this population will be crucial for preventing virus spread and developing effective vaccines.

Discarded polystyrene foams as white wastes, at least two million tons in demand annually in China, are threatening environment and health because of their formidable degradation, which increase in...

High sensitivity, low limit of detection (LOD), and short response and recovery times at room temperature (RT) are critical for gas sensors. For NO2, different binary metal oxide-based sensors were developed to achieve superior performance at elevated temperatures instead of RT. Herein, we report on CuO@CuO and Cu3Mo2O9@CuO sensors with CuO and Cu3Mo2O9 micro/nanorods vertically aligned on the CuO layers, which were directly fabricated using a facile, low-cost, and catalyst-free chemical vapor deposition (CVD) technique. Their sensing performance tests revealed that the Cu3Mo2O9@CuO p-p heterojunction sensors exhibited a high response of 160% to 5 ppm NO2, an excellent sensitivity of 50% ppm-1, a low LOD of 2.30 ppb, a short response time of 49 s, and a rapid recovery of 241 s at RT, obviously better than those for CuO@CuO sensors. The superior performance of Cu3Mo2O9@CuO sensors could be attributed to the Schottky heterojunction formed between p-Cu3Mo2O9 micro/nanorods and p-CuO films, the catalytic effect, and the anisotropic nature of Cu3Mo2O9 micro/nanorods. This study not only provides a simple, low-cost, and batchable fabrication method of homo/heterojunction sensors with micro/nanorods vertically aligned on films but also opens an avenue for sensor design by tuning the Schottky barrier height to enhance RT performance.

Background The coronavirus disease 2019 (COVID-19) has turned into a pandemic and resulted in huge death tolls and burdens. Integrating Chinese and western medicine has played an important role in the fight against the COVID-19 pandemic. Purpose We aimed to develop a living evidence-based guideline of integrating Chinese and western medicine for COVID-19. Study design Living evidence-based guideline. Methods This living guideline was developed using internationally recognized and accepted guideline standards, dynamically monitoring the release of new clinical evidence, and quickly updating the linked living systematic review, evidence summary tables, and recommendations. Modified Delphi method was used to reach consensus for all recommendations. The certainty of the evidence, resources, and other factors were fully considered, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to rate the certainty of evidence and the strength of recommendations. Results The first version of this living guidance focuses on patients who are mild or moderate COVID-19. A multidisciplinary guideline development panel was established. Ten clinical questions were identified based on the status of evidence and a face-to-face experts' consensus. Finally, nine recommendations were reached consensus, and were formulated from systematic reviews of the benefits and harms, certainty of evidence, public accessibility, policy supports, feedback on proposed recommendations from multidisciplinary experts, and consensus meetings. Conclusion This guideline panel made nine recommendations, which covered five traditional Chinese medicine (TCM) prescription granules/decoction (MXXFJD, QFPD, XFBD, TJQW, and JWDY), three Chinese patent medicines (LHQW granules/capsule, JHQG granules, and LHQK granules), and one Chinese herbal injection (XBJ injection). Of them, two were strongly recommended (LHQW granules/capsule and QFPD decoction), and five were weakly recommended (MXXFJD decoction, XFBD decoction, JHQG granules, TJQW granules, and JWDY decoction) for the treatment of mild and moderate COVID-19; two were weakly recommended against (XBJ injection and LHQK granules) the treatment of mild and moderate COVID-19. The users of this living guideline are most likely to be clinicians, patients, governments, ministries, and health administrators.

Li- and Mn-rich layered oxides can deliver high reversible capacity but suffer from severe voltage decay, which seriously impedes their commercial applications. However, high-nickel Li-rich layered oxides could normally present stable discharge voltage but tend to deliver low reversible capacity. In this work, high-nickel Li-rich layered oxides are doped by Mo via a facile sol-gel route to realize both high reversible capacity and minor voltage decay simultaneously. The superior performance could be ascribed to the reduced size of primary particles, the enhanced stability of lattice oxygen and more Mn4+/3+ redox couples effectively activated during the electrochemical reactions which are realized via Mo doping. The present study offers a new strategy to achieve high-performance high-nickel Li-rich layered oxides with both the stable discharge potential and high reversible capacity by modifying their morphologies, structures and chemistries via the introduction of proper alien elements which are believed to be the potential cathode candidates for next generation lithium-ion batteries.

Background: Recovery of the interstitial cells of Cajal (ICCs) during post-operative ileus (POI) is important for the restoration of gastrointestinal (GI) motility. Acupuncture can protect ICCs, but the underlying mechanisms remain unclear. In this study, we investigated whether miR-222, c-kit and endothelial nitric oxide synthase (eNOS) are involved in the putative effects of acupuncture on ICC recovery. Methods: A POI model was established in Sprague-Dawley rats by colo-colic anastomosis, and then acupuncture was performed at bilateral ST36, SP6 and LR3 once daily for 3 consecutive days. C-kit protein expression in the colonic tissue adjacent to the incision site was determined by immunohistochemistry and Western blotting. mRNA levels of c-kit, eNOS and miR-222 were measured by real-time polymerase chain reaction (RT-PCR). Results: The levels of c-kit mRNA/protein and eNOS mRNA decreased, while miR-222 increased in the colonic tissues of POI model rats. Acupuncture treatment improved GI motility, inhibited the up-regulation of miR-222 and blocked the down-regulation of c-kit mRNA/protein and eNOS mRNA. The levels of miR-222 and c-kit were negatively correlated. Conclusion: Acupuncture at ST36, SP6 and LR3 facilitates ICC recovery and improves post-operative GI motility in part through regulation of miR-222, c-kit and eNOS.

It has been well recognized that Li2CO3 is inevitably formed at the surface of nickel rich layered compounds (NRLC) upon storage in air which is usually considered to be detrimental to the performance. Actually, its formation may have been triggered during synthesis of NRLC. However, little is known of its formation during synthesis of NRLC in air and its interaction behaviors with electrolyte during electrochemical process. Herein, we successfully tailor Li2CO3 surface phase simply by controlling calcination time during synthesis of structurally well ordered LiNi0.9Mn0.1O2 particles with great similarity in structure, morphology, size and crystallinity in air using a facile sol-gel method. The thickness of Li2CO3 layer is for the first time observed to decrease with increased calcination time, accompanied by the reduced Ni2+ at surface. More oxygen vacancies caused by more Ni2+ owing to the difficulty of oxidizing Ni2+ to Ni3+ at the surface are proposed here to be responsible for the formation of more Li2CO3 for shorter calcination times. Li2CO3 surface phase is evidenced to favor not only suppressing the H2/H3 phase transition but alleviating the interaction of LiNi0.9Mn0.1O2 with electrolyte because of the coating effect, which therefore improves the cycling stability of LiNi0.9Mn0.1O2 at low rates. Therefore, this study not only provides a new insight into the surface changes of LiNi0.9Mn0.1O2 with calcination time at high temperature during synthesis in air, but opens up a new avenue to tailoring Li2CO3 surface phase as desired by controlling the oxidization extent of Ni2+ to Ni3+ to modulate oxygen vacancies at surface through employing different oxidizing atmospheres or calcination times for performance improvement or exploration of novel preparation approaches of high performance NRLC.

The level of T cell activation is a better predictor of CD4+ T cell depletion in highly active antiretroviral therapy (HAART) patients than viral load. Artesunate is an artemisinin derivative that ...

Novel energy devices which are capable of alleviating and/or solving the energy dilemma such as overall water splitting and fuel cells require the development of highly efficient catalysts, especially cheap high performance non-precious metal (NPM) catalysts. Here, we prepare highly efficient NPM catalysts of cobalt and nitrogen codoped carbon nanosheets (Co/N–CNSs) for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) using harmful environment-polluting waste of biomass catkins as carbon precursors via a mild mechanical exfoliation and chemical process which is facile, low-cost, environmentally friendly and up-scalable. Compared with a commercial platinum-based catalyst (commercial 20% Pt/C), the Co/N–CNS electrocatalysts show outstanding ORR activity, acceptable HER activity and long term stability with an onset potential of 0.92 V versus the reversible hydrogen electrode (vs. RHE) and a half-wave potential of 0.83 V vs. the RHE in alkaline electrolytes. The excellent performance is closely related to the presence of abundant CoNx active sites. This work offers a novel and effective approach for preparing highly efficient ORR and HER NPM electrocatalysts from waste biomass materials.

SARS-CoV-2 has resulted in numerous cases of Coronavirus Disease 2019 (COVID-19) worldwide. In addition to fever and respiratory symptoms, digestive symptoms also are observed in some patients with COVID-19. Angiotensin-converting enzyme 2 (ACE2) was reported to be the receptor for SARS-CoV-2. The aim of this study was to comprehensively investigate the digestive symptoms that occur in COVID-19 patients, and the potential pathogenic route of the SARS-CoV-2 infection in digestive tract organs (from the oral cavity to the gastrointestinal tract). We investigated the digestive symptoms of 48 patients with COVID-19 and explored ACE2 expression in digestive tract and lung cancers, based on a series of bulk and single-cell RNA sequencing data obtained from public databases. We found that 25% (12/48) of the patients with COVID-19 suffered from digestive symptoms, among which pharyngalgia (7/48) was the most common manifestation, followed by diarrhea (3/48), anorexia (3/48), and nausea (1/48). The bulk tissue RNA sequencing analysis indicated that digestive tract organs had higher ACE2 expression levels compared to the lung, and the expression of ACE2 in the lung increased with age. Single-cell RNA-Seq results showed that the ACE2-positive-cell ratio in digestive tract organs was significantly higher compared to the lung. ACE2 expression was higher in tumor cells compared to normal control (NC) tissues. While in gastric tissues, ACE2 expression gradually increased from chronic gastritis to metaplasia, to early cancer. Our data might provide a theoretical basis for screening the SARS-CoV-2 susceptible population and for the clinical classification of treatment of patients with COVID-19.

We report temporal patterns of viral shedding in 94 patients with laboratory-confirmed COVID-19 and modeled COVID-19 infectiousness profiles from a separate sample of 77 infector–infectee transmission pairs. We observed the highest viral load in throat swabs at the time of symptom onset, and inferred that infectiousness peaked on or before symptom onset. We estimated that 44% (95% confidence interval, 30–57%) of secondary cases were infected during the index cases’ presymptomatic stage, in settings with substantial household clustering, active case finding and quarantine outside the home. Disease control measures should be adjusted to account for probable substantial presymptomatic transmission. Presymptomatic transmission of SARS-CoV-2 is estimated to account for a substantial proportion of COVID-19 cases.

High sensitivity, low limit of detection (LOD), and short response and recovery times at room temperature (RT) are critical for gas sensors. For NO

A novel coronavirus (SARS-CoV-2) was identified in December 2019, Wuhan, China. This new coronavirus has resulted in numerous cases of Coronavirus Disease 2019 (COVID-19) throughout the world. Apart from fever and respiratory symptoms, digestive symptoms could be observed in patients with COVID-19. Angiotensin-converting enzyme 2 (ACE2) was reported to be the receptor of SARS-CoV-2. Aim to more comprehensively investigate the digestive symptoms in COVID-19 patients, and the potential pathogenic route of the SARS-CoV-2 infection in digestive tract organs (from oral cavity to gut), we investigated the digestive symptoms of 48 patients with COVID-19, and explored ACE2 expression in digestive tract cancers and lung cancers, based on a series of bulk and single-cell RNA sequencing data from public databases. We found that 25% (12/48) patients with COVID-19 suffered from digestive symptoms, among which pharyngalgia (7/48) was the most common manifestation, followed by diarrhea (3/48), anorexia (3/48), and nausea (1/48). The bulk RNA sequencing analysis indicated that digestive tract organs had higher ACE2 expression than lung and expression of ACE2 in lung increases with age. Single-cell RNA-Seq results showed that ACE2-positive-cell ratio in digestive tract organs was significantly higher than that in lung; ACE2 expression was higher in tumor cells than that in NC tissues; in gastric tissues, ACE2 expression was gradually increased from chronic gastritis, metaplasia to early cancer. Our data may provide a theoretical basis for the screening of SARS-CoV-2 susceptible population, and for the clinical classification for treatment of patients with COVID-19. Funding Statement: This work was supported by the Guangdong Financial Fund for High-Caliber Hospital Construction. Declaration of Interests: The authors have no conflicts of interest. Ethics Approval Statement: This study was approved by the institutional ethics board of Guangzhou Eighth People’s Hospital (No. 202006139).

Background: Coronavirus Disease 2019 (COVID-19) is wreaking havoc throughout the world However, we know little about the virus load and changes of laboratory i

In this work, octahedral LiMn2O4 (O-LMO) with exposed {111} crystal facets was prepared using MnCO3 as a precursor via solid phase reactions. O-LMO was revealed to have the superior rate performance and good cycling stability in both a three-electrode system and full aqueous batteries with Li2SO4 solution.The capacity retentions of 87% for 200 cycles at 0.1 A g-1 and 87% for 500 cycles at 1 A g-1 were achieved, in sharp contrast with 56% and 70% for the commercial LMO (C-LMO). Also, O-LMO showed the excellent performance in organic systems as well. The superior performance for both aqueous and organic systems may be related to the maintaining of octahedral structures and surface morphologies for O-LMO cycled 200 times at 0.1 A g-1 in aqueous system and the suppression of Mn dissolution and side reactions in both aqueous and organic systems, which originates from the stable {111} facets.

2D hierarchically porous carbon (2D-HPC) nanosheets with unique advantages are highly desired as host materials for lithium sulfur (Li-S) batteries and other energy storage devices. Herein, we propose a self-template and organic solvent-free approach to synthesize nanosheets of monoclinic ZIF-8 at room temperature from which 2D-HPC nanosheets (ZIF-8 nanosheets carbon denoted as ZIF-8-NS-C) are derived to be an efficient sulfur immobilizer for Li-S batteries for the first time. The anisotropic nanosheets are believed to relate to the symmetry of the monoclinic structure. The 2D ZIF-8-NS-C nanosheets with embedded hierarchical pores construct an effective conductive network through "plane-to-plane" modes to endow superior electron transfer and fast electrochemical kinetics. Moreover, the nitrogen-rich feature of ZIF-8-NS-C can increase the affinity/interaction of carbon host with lithium polysulfides, favoring the cyclic performance. The sulfur/ZIF-8-NS-C (S/ZIF-8-NS-C) cathode shows a superior rate capability with high capacities of 1226 mA h g-1 at 0.2 C and 785 mA h g-1 at 2 C, and a sustainable cycling stability with a capacity attenuation of 0.12% per cycle at 0.5 C for 300 cycles. The approach proposed here pioneers the controllable design of MOF-based structures to inspire the exploration of more variable MOF-derived porous materials for energy storage applications.

Acupuncture is a therapy effective in treating postoperative ileus (POI); its underlying mechanisms remain unclear. MicroRNAs (miRNAs) participate in inflammation and injury to the interstitial cells of Cajal (ICCs), both of which are considered to be contributors to POI. C-kit, encoding KIT, a specific marker of ICCs, is predicted to be targeted by miR-19a, an inflammation-related miRNA. Therefore, we investigated a possible link between inflammation, miR-19a, and ICCs in POI, as well as the mechanism by which these factors are affected by acupuncture. The effects of acupuncture on POI were assessed in patients after colorectal resection and in colocolic anastomosis mice. Immunofluorescence staining demonstrated that KIT[Formula: see text]/ano1[Formula: see text] ICCs dramatically decreased around the colonic incision in mice, which was negatively correlated with the pronounced increase in macrophage. However, this decrease was not due to apoptosis. IL-6R was expressed in ICCs, and IL-6 level was significantly increased, as measured by ELISA, in accompaniment with high miR-19a expression. The increase in IL-6 and miR-19a levels was negatively correlated with the decrease in KIT[Formula: see text]/ano1[Formula: see text] ICCs. A luciferase reporter assay demonstrated that miR-19a directly targeted C-kit, indicating that miR-19a caused ICC damage. Interestingly, acupuncture inhibited macrophage activation, IL-6 release, and miR-19a upregulation, while promoting KIT and ano1 restoration in ICCs. High serum miR-19a level in patients after colorectal resection was also reduced by acupuncture. Conclusively, the IL-6 released by macrophages during gastrointestinal surgery upregulated miR-19a, which downregulated KIT in ICCs and finally resulted in POI. Acupuncture can interfere with the “IL-6–miR-19a–KIT” axis, suggesting that it may be a therapeutic mechanism that works against POI.

A facile graphite assisted approach is proposed to synthesize high performance LiMn2O4 nanostructures. Graphite plates with different sizes and thicknesses are found to have different influences on the structure, morphology and performance of LiMn2O4. Larger and thicker graphite plates result in 2-D porous LiMn2O4 nanoplates whereas smaller and thinner ones lead to the formation of dispersed nanoparticles. Despite the smaller lattice constant, the shorter Li O and longer Mn O bonds, and the lower BET surface area compared to dispersed LiMn2O4 nanoparticles, LiMn2O4 nanoplates formed by primary nanoparticles with similar sizes and morphologies exhibit the superior performance because of the better interparticle electronic conductivity. LiMn2O4 nanoplates show the discharge capacity of 104 mAh g−1 at 50 C and the capacity retention of 70.0% after 1000 cycles for 1 C at RT, better than the corresponding values, 95 mAh g−1 and 64.5% for dispersed LiMn2O4 nanoparticles, respectively. The more superior performance of LiMn2O4 nanoplates compared to dispersed LiMn2O4 nanoparticles is particularly manifested in the case of lower percentage conductive additive, which is very significant for practical application. This simple, cost effective, green and up scalable approach can also be employed to synthesize other 2–D nanostructured materials.

Metal Mn powders instead of conventional Mn salts were used for the first time tried as a Mn source to synthesize high-performance LiNi0.5Mn1.5O4 (M-LNMO) using a sol–gel method. Mn powders promote the formation of well-crystallized octahedra with the Fd3m spinel structure. M-LNMO has a lower stress, a slightly smaller lattice constant, which arises from the lower amount of Mn3+ because of the lower oxygen deficiency, a higher cation ordering, and longer Li−O and shorter Mn (Ni)−O bonds than LiNi0.5Mn1.5O4 synthesized from manganese acetate (MA-LNMO). The well-crystallized octahedra, the low stress, the low amount of Mn3+, and the long Li−O and short Mn (Ni)−O bonds for M-LNMO result in its excellent performance such as a discharge capacity of 68 mAh g−1 at 50 C and a capacity retention of 90 % after 600 cycles at 10 C. This study raises the possibility to promote the synthesis of high-performance LiNi0.5Mn1.5O4 for mass production by using cheap and simple Mn sources such as Mn powders.

LiFePO4 nanoparticles with different morphologies and sizes were synthesized via a solvothermal method using environmentally benign and low-cost glycerol as the surfactant. The morphology, size, and structure of the particles were found to relate closely to the concentration of glycerol. Oriented linked LiFePO4 nanorods along mostly non-[010] were obtained with the proper concentration of glycerol. The nanorods showed good electronic and ionic conductivities, resulting in superior rate capability and cycling performance. This performance was attributed to the oriented linkages along mostly non–[010], the small particle size along [010], and the occupation of Li at Fe sites. Initial discharge capacities of 162.4 mA·h·g–1 at 0.1 C and 102.1 mA·h·g–1 at 30 C were achieved, with capacity retentions after 500 cycles at 5 and 20 C of 99.5% and 93.2%, respectively. At the rate of 40 C, the solid-solution phase transition dominated during lithiation and delithiation of all samples.