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Host-less lithium metal anode generally suffers from large volume changes and serious dendrite growth during cycling, which poses challenges for its practical application. Interpenetrating phase composites with continuous architectures offer a solution to enhance mechanical properties of materials. Herein, a robust composite Li anode (LBN) material is fabricated through the metallurgical reaction between Li and hexagonal boron nitride (h-BN) with the formation of interpenetrating LiB/Li3BN2 phases. As LiB fibers are anchored by Li3BN2 granules, the collapse and slippage of LiB fibers are suppressed whilst the mechanical strength and structural stability of LBN are reinforced. By rolling, ultrathin (15 µm), freestanding, and electrochemically stable LBN foil can be obtained. The LBN anode exhibits a high average Coulombic efficiency of 99.69% (1 mA cm-2, 3 mAh cm-2) and a long lifespan of 2500 h (1 mA cm-2, 1 mAh cm-2). Notably, the LiCoO2 (with double-sided load 40 mg cm-2)|LBN pouch cell can operate over 450 cycles with a capacity retention of 90.1%. The exceptional cycling stability of LBN can be ascribed to the interpenetrating reinforcement architectures and synergistic electronic/ionic conductivity of the LiB/Li3BN2 dual-lithiophilic-phases. This work provides a new methodology for thin Li strip processing and reinforced-architecture design, with implications beyond battery applications.
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The development of lithium (Li) metal batteries (LMBs) has been limited by problems, such as severe dendrite growth, drastic interfacial reactions, and large volume change. Herein, an LMB (8AP@LiB) combining agraphene oxide-poly(ethylene oxide) (PEO) functionalized polypropylene separator (8AP) with a lithium-boron (LiB) anode is designed to overcome these problems. Raman results demonstrate that the PEO chain on 8AP can influence the Li+ solvation structure in the electrolyte, resulting in Li+ homogeneous diffusion and Li+ deposition barrier reduction. 8AP exhibits good ionic conductivity (4.9 × 10-4 S cm-1), a high Li+ migration number (0.88), and a significant electrolyte uptake (293%). The 3D LiB skeleton can significantly reduce the anode volume changes and local current density during the charging/discharging process. Therefore, 8AP@LiB effectively regulates the Li+ flux and promotes the uniform Li deposition without dendrites. The Li||Li symmetrical cells of 8AP@LiB exhibit a high electrochemical stability of up to 1000 h at 1 mA cm-2 and 5 mAh cm-2. Importantly, the Li||LiFePO4 full cells of 8AP@LiB achieve an impressive 2000 cycles at 2C, while maintaining a high-capacity retention of 86%. The synergistic effect of the functionalized separator and LiB anode might provide a direction for the development of high-performance LMBs.
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The practical application of Li metal anodes (LMAs) is limited by uncontrolled dendrite growth and side reactions. Herein, we propose a new friction-induced strategy to produce high-performance thin Li anode (Li@CFO). By virtue of the in situ friction reaction between fluoropolymer grease and Li strips during rolling, a robust organic/inorganic hybrid interlayer (lithiophilic LiF/LiC6 framework hybridized -CF2-O-CF2- chains) was formed atop Li metal. The derived interface contributes to reversible Li plating/stripping behaviors by mitigating side reactions and decreasing the solvation degree at the interface. The Li@CFO||Li@CFO symmetrical cell exhibits a remarkable lifespan for 5,600 h (1.0 mA cm-2 and 1.0 mAh cm-2) and 1,350 cycles even at a harsh condition (18.0 mA cm-2 and 3.0 mAh cm-2). When paired with high-loading LiFePO4 cathodes, the full cell lasts over 450 cycles at 1C with a high-capacity retention of 99.9%. This work provides a new friction-induced strategy for producing high-performance thin LMAs.
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A practical high-specific-energy Li metal battery requires thin (≤20 µm) and free-standing Li metal anodes, but the low melting point and strong diffusion creep of lithium metal impede their scalable processing towards thin-thickness and free-standing architecture. In this paper, thin (5 to 50 µm) and free-standing lithium strips were achieved by mechanical rolling, which is determined by the in situ tribochemical reaction between lithium and zinc dialkyldithiophosphate (ZDDP). A friction-induced organic/inorganic hybrid interface (~450 nm) was formed on Li with an ultra-high hardness (0.84 GPa) and Young's modulus (25.90 GPa), which not only enables the scalable process mechanics of thin lithium strips but also facilitates dendrite-free lithium metal anodes by inhibiting dendrite growth. The rolled lithium anode exhibits a prolonged cycle lifespan and high-rate cycle stability (in excess of more than 1700 cycles even at 18.0 mA cm-2 and 1.5 mA cm-2 at 25 °C). Meanwhile, the LiFePO4 (with single-sided load 10 mg/cm2) ||Li@ZDDP full cell can last over 350 cycles with a high-capacity retention of 82% after the formation cycles at 5 C (1 C = 170 mA/g) and 25 °C. This work provides a scalable approach concerning tribology design for producing practical thin free-standing lithium metal anodes.
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The commercialization pace of aqueous zinc batteries (AZBs) is seriously limited due to the uncontrolled dendrite growth and severe corrosion reaction of the zinc anode. Herein, a universal and extendable saturated fatty acid-zinc interfacial layer strategy for modulating the interfacial redox process of zinc toward ultrastable Zn metal anodes is proposed. The in situ complexing of saturated fatty acid-zinc interphases could construct an extremely thin zinc compound layer with continuously constructed zincophilic sites which kinetically regulates Zn nucleation and deposition behaviors. Furthermore, the multifunctional interfacial layer with internal hydrophobic carbon chains as a protective layer is efficient to exclude active water molecules from the surface and efficiently inhibit the surface corrosion of zinc. Consequently, the modified anode shows a long cycle life of over 4000 h at 5 mA cm-2. In addition, the assembled Zn||V2O5 full cells based on modified zinc anodes have excellent rate performance and long cycle stability.
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Lithium metal is a promising anode for high-energy-density lithium batteries, but its practical application is still hindered by intrinsic defects such as infinite volume expansion and uncontrollable dendrite growth. Herein, a dendrite-free 3D composite Li anode (Li-B@SSM) is prepared by mechanical rolling of lithiophilic LiB nanofibers supported by Li-B composite and lithiophobic stainless-steel mesh (SSM). Featuring hierarchical lithiophilic-lithiophobic dual-skeletons, the Li-B@SSM anode shows an ultrahigh Coulombic efficiency of 99.95% and a long lifespan of 900 h under 2 mA cm-2 /1 mAh cm-2 . It is demonstrated that the abnormally reversible Li stripping/plating processes should be closely related to the site-selective plating behavior and spatial confinement effect induced by the robust lithiophilic-lithiophobic dual-skeletons, which alleviates the volume changes, suppresses the growth of Li dendrites, and reduces the accumulation of "dead" Li. More importantly, the application feasibility of the Li-B@SSM anode is also confirmed in full batteries, of which the Li-B@SSM|LiFePO4 full cell shows a high capacity retention of 97.5% after 400 cycles while the Li-B@SSM|S pouch battery exhibits good cycle stability even under practically harsh conditions. This work paves the way for the facile and efficient fabrication of high-efficiency Li metal anodes toward practical applications.
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The coronavirus disease 2019 (COVID-19) epidemic has been almost controlled in China under a series of policies, including "early diagnosis and early treatment". This study aimed to explore the association between early treatment with Qingfei Paidu decoction (QFPDD) and favorable clinical outcomes. In this retrospective multicenter study, we included 782 patients (males, 56 %; median age 46) with confirmed COVID-19 from 54 hospitals in nine provinces of China, who were divided into four groups according to the treatment initiation time from the first date of onset of symptoms to the date of starting treatment with QFPDD. The primary outcome was time to recovery; days of viral shedding, duration of hospital stay, and course of the disease were also analyzed. Compared with treatment initiated after 3 weeks, early treatment with QFPDD after less than 1 week, 1-2 weeks, or 2-3 weeks had a higher likelihood of recovery, with adjusted hazard ratio (HR) (95 % confidence interval [CI]) of 3.81 (2.65-5.48), 2.63 (1.86-3.73), and 1.92 (1.34-2.75), respectively. The median course of the disease decreased from 34 days to 24 days, 21 days, and 18 days when treatment was administered early by a week (P < 0.0001). Treatment within a week was related to a decrease by 1-4 days in the median duration of hospital stay compared with late treatment (P<0.0001). In conclusion, early treatment with QFPDD may serve as an effective strategy in controlling the epidemic, as early treatment with QFPDD was associated with favorable outcomes, including faster recovery, shorter time to viral shedding, and a shorter duration of hospital stay. However, further multicenter, prospective studies with a larger sample size should be conducted to confirm the benefits of early treatment with QFPDD.
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Tratamento Farmacológico da COVID-19 , Medicamentos de Ervas Chinesas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Estudos de Coortes , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Tempo para o Tratamento , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To evaluate the effects of heat inactivation of blood samples at 56â for 30 min on the results of SARS-CoV-2 antibody detection using different methods. METHODS: This retrospective study was conducted in 11 patients with established diagnosis of COVID-19 and 10 patients with diseases other than COVID- 19 in our hospital. We collected samples of serum, plasma and whole blood from each patient between February, 12 and 18, 2020, and with a double- blind design, the samples were examined for SARS-CoV-2 antibodies before and after heat inactivation at 56 â for 30 min. In all the samples, the total SARS-CoV-2 antibodies were detected using immunochromatography, and the IgM antibodies were detected using fluorescence immunochromatography; the IgM and IgG antibodies in the serum and plasma samples detected with chemiluminescence immunoassay. We compared the detection results and analyzed the correlation of semi-quantitative detection results of IgM and IgG antibodies before and after heat inactivation of the samples. RESULTS: With immuno-chromatography, the coincidence rate of the total SARS-CoV-2 antibody detection before and after heat inactivation of the serum and plasma samples was 90.0% in COVID-19 cases and 100.0% in the negative cases, resulting in a total coincidence rate 95.2%; for the whole blood samples, the total coincidence rates of the total SARS-CoV-2 antibodies were 100.0%. For detection of IgM antibodies in the serum, plasma and whole blood samples using fluorescence immunochromatography, the coincidence rates in SARS-CoV-2-positive and negative cases and the total coincidence rate before and after inactivation were 100.0%, 0 and 47.6%, respectively. For detection of serum IgM and IgG antibodies and plasma IgG antibodies with chemiluminescence immunoassay, the coincidence rates in SARS-CoV-2-positive and negative cases and the total coincidence rate before and after inactivation were all 100.0%, and the total coincidence rate of plasma IgM antibodies was 95.2%. Pearson correlation analysis of the semi-quantitative results of IgM and IgG detection in the serum and plasma samples showed a correlation coefficient of 0.9999 (95%CI: 0.9998-1.000, P < 0.001) between the results before and after sample inactivation. CONCLUSIONS: Heat inactivation of blood samples at 56 â for 30 min does not obviously affect the results of immunochromatography and chemiluminescent immunoassay for detection of SARS-COV-2 antibodies but can reduce the risk of infection for the operators. Heat-inactivated samples can not be used in fluorescence immunochromatography for SARS-CoV-2 antibody detection.
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Betacoronavirus , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Anticorpos Antivirais , COVID-19 , Ensaio de Imunoadsorção Enzimática , Temperatura Alta , Humanos , Imunoglobulina G , Imunoglobulina M , Pandemias , Estudos Retrospectivos , SARS-CoV-2RESUMO
Numerous chiral drugs have been developed for neurological diseases, but chiral drug safety and pharmacological research still faces great challenges in enantioselectivity and sensitivity of chiral analysis. A rapid, stable and high-efficiency gold nanodendrite-based electrochemical sensing method was proposed as a versatile differential potential ratiometric strategy for highly selective chiral recognition of dual 3,4-dihydroxyphenylalanine (DOPA) enantiomers. Using simple electrochemical deposition, the gold nanodendrite (AuND) membrane was steadily modified on the glassy carbon electrode (GCE) with high specific chiral identifiability and robust signal amplifiability. Based on a sequence of systematic optimization, an apparent potential difference (PD) was detected up to 108 mV from oxidation peaks of DOPA enantiomers. Furthermore, according to a regulatable concentration range from 10 µM to 100 µM, different proportions of L-/d-DOPA had a good linear relationship with corresponding peak potentials (Eps) in the racemic mixture. Superior to traditional enantiorecognition of single chiral drug, both DOPA enantiomers enabled to be simultaneously distinguished with high repeatability, selectivity, and anti-interference ability on the AuND/GCE. This unique semi-quantitative AuND-based potential sensing strategy was proposed to efficiently quantify the proportion of L-/d-DOPA for chiral drug recognition, emerging positive potential for numerous applications in pharmacology and clinical diagnosis.
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Di-Hidroxifenilalanina/análise , Ouro/química , Nanoporos , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Estrutura Molecular , Tamanho da Partícula , Estereoisomerismo , Propriedades de SuperfícieRESUMO
BACKGROUND: Anguilla japonica (Japanese eel) is currently one of the most important research subjects in eastern Asia aquaculture. Enigmatic life cycle of the organism makes study of artificial reproduction extremely limited. Henceforth genomic and transcriptomic resources of eels are urgently needed to help solving the problems surrounding this organism across multiple fields. We hereby provide a reconstructed transcriptome from deep sequencing of juvenile (glass eels) whole body samples. The provided expressed sequence tags were used to annotate the currently available draft genome sequence. Homologous information derived from the annotation result was applied to improve the group of scaffolds into available linkage groups. RESULTS: With the transcriptome sequence data combined with publicly available expressed sequence tags evidences, 18,121 genes were structurally and functionally annotated on the draft genome. Among them, 3,921 genes were located in the 19 linkage groups. 137 scaffolds covering 13 million bases were grouped into the linkage groups in additional to the original partial linkage groups, increasing the linkage group coverage from 13 to 14%. CONCLUSIONS: This annotation provide information of the coding regions of the genes supported by transcriptome based evidence. The derived homologous evidences pave the way for phylogenetic analysis of important genetic traits and the improvement of the genome assembly.
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Anguilla/genética , Genoma , Animais , Mapeamento Cromossômico , Peixes/genética , Ligação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Polimorfismo de Nucleotídeo Único , Receptores Citoplasmáticos e Nucleares/classificação , Receptores Citoplasmáticos e Nucleares/genética , Análise de Sequência de RNA , Fatores de Transcrição/classificação , Fatores de Transcrição/genéticaRESUMO
OBJECTIVE: To observe the clinical effect and mechanism of migraine treated with pine needle moxibustion. METHODS: Forty-three patients were randomly divided into 2 groups of pine needle moxibustion group (group A, 21 cases) and medicated thread moxibustion of Zhuang medicine group (group B, 22 cases). Same acu-points were selected as the main points for both groups, namely Fengchi (GB 20), Baihui (GV 20), Taiyang (EX-HN 5), Shuaigu (GB 8), Cuanzhu (BL 2), Sizhukong (TE 23), Yanglingquan (GB 34), Waiguan (TE 5) and Ashi points. Pine needle moxibustion was applied for the group A. Processed lighted pine needles were banded together with one even head to do moxibustion on acupoints or pain points. While, lighted medicated thread was adopted for the group B to do moxibustion. Therapeutic effects, the content of high-sensitivity C-reactive protein (hs-CRP), Mg2+ in the serum and the degree of pain of the two groups were compared. RESULTS: (1) In the group A, the complete remission rate was 47.6% (10/21) and the effective rate was 90.5% (19/21). In the group B, the complete remission rate was 13.6% (3/22) and the effective rate was 50.0% (11/22). The two rates in the group A were superior to those in the group B (both P < 0.01); (2) In the group A, the content of hs-CRP was decreased from (4.29 +/- 0.98) mg/L to (2.11 +/- 0.87) mg/L, and Mg2+ was increased from (0.67 +/- 0.28) mmol/L to (1.07 +/- 0.16) mmol/L. In the group B, the contents of the above mentioned indices were respectively decreased from (4.30 +/- 1.07) mg/L to (3.38 +/- 1.15) mg/L and increased from (0.68 +/- 0.21) mmol/L to (0.88 +/- 0.25) mmol/L. There were significant differences between the two groups after treatment (both P < 0.05). (3) The degree of pain in the group A after treatment was much lower than that in the group B (P < 0.05). CONCLUSION: The clinical effect of migraine treated with pine needle moxibustion is better than that with the medicated thread moxibustion of Zhuang medicine. And it has obvious regulation effect on the levels of hs-CRP and Mg2+ in the serum of patients.