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1.
World J Gastrointest Surg ; 15(11): 2663-2673, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38111758

RESUMO

BACKGROUND: Perihilar cholangiocarcinoma (pCCA) is a highly malignant tumor arising from the biliary tree. Radical surgery is the only treatment offering a chance of long-term survival. However, limited by the tumor's anatomic location and peri-vascular invasion, most patients lose the chance for curative treatment. Therefore, more methods to increase the resectability of tumors as well as to improve outcomes are needed. CASE SUMMARY: A 68-year-old female patient had a hepatic hilar mass without obvious symptoms. Laboratory results showed hepatitis B positivity. Magnetic resonance imaging indicated that the mass (maximum diameter: 41 mm) invaded the left and right branches of the main portal vein, as well as the middle, left and right hepatic veins; enlarged lymph nodes were also detected in the hilum. The patient was diagnosed with pCCA, and the clinical stage was determined to be T4N1M0 (stage IIIC). Considering the tumor's anatomic location and vascular invasion, systematic conversion therapy followed by ex vivo liver resection and autotransplantation (ELRA) was determined as personalized treatment for this patient. Our original systemic sequential therapeutic strategy (lenvatinib and tislelizumab in combination with gemcitabine and cisplatin) was successfully adopted as conversion therapy because she achieved partial response after three cycles of treatment, without severe toxicity. ELRA, anastomotic reconstruction of the middle hepatic vein, right hepatic vein, root of portal vein, inferior vena cava and right hepatic artery, and lymph node dissection were performed at one month after systemic therapy. Pathological and immunohistochemical examination confirmed the diagnosis of pCCA with lymph node metastasis. Although the middle hepatic vein was partially obstructed four months later, hepatic vein stent implantation successfully addressed this problem. The patient has survived for 22 mo after the diagnosis, with no evidence of recurrence or metastasis. CONCLUSION: An effective therapeutic strategy for conversion therapy greatly increases the feasibility and efficiency of ELRA.

2.
Fa Yi Xue Za Zhi ; 39(3): 288-295, 2023 Jun 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37517018

RESUMO

OBJECTIVES: To investigate the efficacy of different numbers of microhaplotype (MH) loci and the introduction of different reference samples on the identification of full sibling, half sibling and differentiation between full sibling and half sibling kinships, and to explore the effect of changing mutation rate on sibling testing. METHODS: First, a family map involving three generations was established, and four full sibling identification models, five half sibling identification models and five models distinguishing full and half siblings were constructed for different reference samples introduced. Based on the results of the previous study, two sets of nonbinary SNP-MH containing 34 and 54 loci were selected. Based on the above MH loci, 100 000 pairs of full sibling vs. unrelated individuals, 100 000 pairs of half sibling vs. unrelated individuals and 100 000 pairs of full sibling vs. half sibling were simulated based on the corresponding sibling kinship testing models, and the efficacy of each sibling kinship testing model was analyzed by the likelihood ratio algorithm under different thresholds. The mutant rate of 54 MH loci was changed to analyze the effect of mutation rate on sibling identification. RESULTS: In the same relationship testing model, the systematic efficacy of sibling testing was positively correlated with the number of MH loci detected. With the same number of MH loci, the efficacy of full sibling testing was better than that of uncle or grandfather when the reference sample introduced was a full sibling of A, but there was no significant difference in the identification efficacy of the four reference samples introduced for full sibling and half sibling differentiation testing. In addition, the mutation rate had a slight effect on the efficacy of sibling kinship testing. CONCLUSIONS: Increasing the number of MH loci and introducing reference samples of known relatives can increase the efficacy of full sibling testing, half sibling testing, and differentiation between full and half sibling kinships. The level of mutation rate in sibling testing by likelihood ratio method has a slight but insignificant effect on the efficacy.


Assuntos
Polimorfismo de Nucleotídeo Único , Irmãos , Humanos , Impressões Digitais de DNA/métodos
3.
ACS Appl Mater Interfaces ; 15(4): 5326-5335, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36690409

RESUMO

The ever-growing demand for portable electronic devices has put forward higher requirements on the energy density of layered LiCoO2 (LCO). The unstable surface structure and side reactions with electrolytes at high voltages (>4.5 V) however hinder its practical applications. Here, considering the high-voltage stability and three-dimensional lithium-ion transport channel of the high-voltage Li-containing spinel (M = Ni and Co) LiMxMn2-xO4, we design a conformal and integral LiNixCoyMn2-x-yO4 spinel coating on the surface of LCO via a sol-gel method. The accurate structure of the coating layer is identified to be a spinel solid solution with gradient element distribution, which compactly covers the LCO particle. The coated LCO exhibits significantly improved cycle performance (86% capacity remained after 100 cycles at 0.5C in 3-4.6 V) and rate performance (150 mAh/g at a high rate of 5C). The characterizations of the electrodes from the bulk to surface suggest that the conformal spinel coating acts as a physical barrier to inhibit the side reactions and stabilize the cathode-electrolyte interface (CEI). In addition, the artificially designed spinel coating layer is well preserved on the surface of LCO after prolonged cycling, preventing the formation of an electrochemically inert Co3O4 phase and ensuring fast lithium transport kinetics. This work provides a facile and effective method for solving the surface problems of LCO operated at high voltages.

4.
Angew Chem Int Ed Engl ; 62(5): e202215131, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36471651

RESUMO

Charge compensation on anionic redox reaction (ARR) has been promising to realize extra capacity beyond transition metal redox in battery cathodes. The practical development of ARR capacity has been hindered by high-valence oxygen instability, particularly at cathode surfaces. However, the direct probe of surface oxygen behavior has been challenging. Here, the electronic states of surface oxygen are investigated by combining mapping of resonant Auger electronic spectroscopy (mRAS) and ambient pressure X-ray photoelectron spectroscopy (APXPS) on a model LiCoO2 cathode. The mRAS verified that no high-valence oxygen can sustain at cathode surfaces, while APXPS proves that cathode electrolyte interphase (CEI) layer evolves and oxidizes upon oxygen gas contact. This work provides valuable insights into the high-valence oxygen degradation mode across the interface. Oxygen stabilization from surface architecture is proven a prerequisite to the practical development of ARR active cathodes.

5.
Journal of Forensic Medicine ; (6): 288-295, 2023.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-981863

RESUMO

OBJECTIVES@#To investigate the efficacy of different numbers of microhaplotype (MH) loci and the introduction of different reference samples on the identification of full sibling, half sibling and differentiation between full sibling and half sibling kinships, and to explore the effect of changing mutation rate on sibling testing.@*METHODS@#First, a family map involving three generations was established, and four full sibling identification models, five half sibling identification models and five models distinguishing full and half siblings were constructed for different reference samples introduced. Based on the results of the previous study, two sets of nonbinary SNP-MH containing 34 and 54 loci were selected. Based on the above MH loci, 100 000 pairs of full sibling vs. unrelated individuals, 100 000 pairs of half sibling vs. unrelated individuals and 100 000 pairs of full sibling vs. half sibling were simulated based on the corresponding sibling kinship testing models, and the efficacy of each sibling kinship testing model was analyzed by the likelihood ratio algorithm under different thresholds. The mutant rate of 54 MH loci was changed to analyze the effect of mutation rate on sibling identification.@*RESULTS@#In the same relationship testing model, the systematic efficacy of sibling testing was positively correlated with the number of MH loci detected. With the same number of MH loci, the efficacy of full sibling testing was better than that of uncle or grandfather when the reference sample introduced was a full sibling of A, but there was no significant difference in the identification efficacy of the four reference samples introduced for full sibling and half sibling differentiation testing. In addition, the mutation rate had a slight effect on the efficacy of sibling kinship testing.@*CONCLUSIONS@#Increasing the number of MH loci and introducing reference samples of known relatives can increase the efficacy of full sibling testing, half sibling testing, and differentiation between full and half sibling kinships. The level of mutation rate in sibling testing by likelihood ratio method has a slight but insignificant effect on the efficacy.


Assuntos
Humanos , Irmãos , Polimorfismo de Nucleotídeo Único , Impressões Digitais de DNA/métodos
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1009446

RESUMO

Objective To investigate the fluorescence resonance energy transfer (FRET) effect between dylight (DL) and AuNP (AuNP), and to construct a new fluorescence immunoassay for insulin in combination with the immunocompetition method. Methods Insulin antigen (Ag) and insulin antibody (Ab) were conjugated with DL and AuNP respectively to form DL-Ag conjugate and AUNp-AB conjugate. A novel fluorescence immunoassay for insulin was developed on the basis of FRET effect and the immune competition response between them. Then the performance of the method was evaluated and its application in actual samples was explored. Results The fluorescence immunoassay showed high sensitivity (0.015 ng/mL), short measurement time (4 min) and good specificity. It was successfully used in the measurement of serum insulin, and the recovery was between 96.9% and 121.1%. Conclusion FRET effect between AuNP and DL can be applied to develop a fluorescence immunoassay for the measurement of serum insulin.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Insulina , Imunoensaio
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-982789

RESUMO

Myoepithelioma, also known as malignant myoepithelioma, is a rare malignant tumor originating from myoepithelial cell. This article reports a patient with a huge tumor in the neck and left elbow who underwent fine needle aspiration under local anesthesia. The pathological diagnosis was a myoepithelioma. Under general anesthesia, giant tumors in the lower neck, posterior cranial fossa, neck, and left elbow were removed, and postoperative pathology showed that they were all myoepithelial tumors. Immunohistochemistry showed AE1/AE3 (+), P63 (+), CK7 (+), CK5 (+), and CD138 (+). The clinical characteristics and diagnosis and treatment process of this case are reported and relevant literature is reviewed.


Assuntos
Humanos , Mioepitelioma/patologia , Imuno-Histoquímica , Células Epiteliais , Pescoço/patologia , Carcinoma
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-982738

RESUMO

Neuroendocrine carcinoma(NEC) is a malignant tumor derived from neuroendocrine cells, with distinct clinical, morphological and immunohistochemical characteristics. Neuroendocrine carcinoma of the head and neck is very rare in clinic. Larynx is the most common affected site, and the root of the tongue is extremely rare. The clinical manifestations are mainly eating pain, cauliflower like mass in the mouth, and ulcerative lesions that have not healed for a long time. Maxillofacial MRI and contrastenhanced CT are the most commonly used examination tools for such diseases, which can detect the spaceoccupying lesions of tumors. Neuroendocrine granules found in the cytoplasm under pathological light microscope can be diagnosed as neuroendocrine carcinoma. However, for most cases, it is difficult to make a diagnosis only under light microscope, and it is often necessary to make a diagnosis by means of immunohistochemistry and other technical means. This paper reports a case of neuroendocrine carcinoma of the root of the tongue, introduces its characteristics, diagnosis and treatment, and reviews the relevant literature of this case.


Assuntos
Humanos , Carcinoma Neuroendócrino/patologia , Língua , Pescoço/patologia , Laringe/patologia , Boca/patologia
9.
Mitochondrial DNA B Resour ; 7(7): 1280-1281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844976

RESUMO

In this study, we assembled and described the complete chloroplast genome (cp) of Sinosenecio baojingensis Ying Liu & Q.E. Yang (Asteraceae) for the first time. The cp genome is 151,315 bp in length and exhibits a typical quadripartite structure, consisting of a large single-copy (LSC) region of 83,445 bp, a small single-copy (SSC) region of 18,172 bp, and a pair of inverted repeat regions (IRs) of 24,849 bp. A total of 133 genes were annotated, including 88 protein-coding genes (one pseudo gene), 37 tRNA genes (tRNAs), and eight ribosomal RNA genes (rRNAs). Further, the phylogenetic analysis based on eight complete chloroplast genomes indicates that S. baojingensis is shown to be a sister to S. jishouensis. The complete chloroplast genome of S. baojingensis provides significant molecular markers for the studies on phylogeny and species identification of this genus.

10.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2778-2787, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35718498

RESUMO

The present study explored the mechanism of Qingwei Powder(QP) in the treatment of periodontitis based on chromatography-mass spectrometry and network pharmacology-molecular docking techniques. UPLC-Q-TOF-MS and GC-MS were used to identify the chemical constituents of QP. The active components and targets were screened out through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), and their targets were predicted using SwissTargetPrediction. Targets related to periodontitis were obtained from GeneCards, OMIM, and DisGeNET. Venn diagram was constructed using Venny 2.1 to obtain the intersection targets. Cytoscape 3.7.2 was used to construct the "chemical component-target-disease" network. The targets were analyzed for Gene Ontology(GO) function and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment by clusterProfiler R, and the "chemical component-target-pathway" network was constructed. The binding activity of the active components to the target proteins was verified by molecular docking. A total of 189 chemical components were obtained by UPLC-Q-TOF-MS and GC-MS, including 39 active components with 180 potential targets related to periodontitis. Target enrichment analysis of the active components yielded 92 KEGG pathways. Twenty KEGG pathways, 34 active components, and 99 targets were involved in the "chemical component-target-pathway" network. Molecular docking verified a good binding ability of the key targets to the key compounds. This study preliminarily indicates that QP is effective in treating periodontitis through multiple components, multiple targets, and multiple pathways, which reflects the complex system of Chinese medicine. This study provides the theoretical foundation for the subsequent research on the material basis and key quality attributes of QP.


Assuntos
Medicamentos de Ervas Chinesas , Periodontite , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Farmacologia em Rede , Periodontite/tratamento farmacológico , Pós
11.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2629-2633, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34296557

RESUMO

Hyperprolactinemia(HPRL) is one of the diseases leading to anovulatory infertility, which is a refractory gynecological disease and seriously affects female reproductive function. Professor MA Kun has summarized his experience in clinical and scientific studies for many years. And believes that kidney deficiency is the pathogenesis of HPRL and blood stasis is the dominant pathological manifestation of HPRL and can promote the progress of the disease. In view of this, Professor MA Kun took the therapy of kidney-tonifying and blood-activating as the principle for treating anovulatory infertility caused by HPRL, with soothing the liver and promoting Qi as adjuvant therapies. She has also summarized and refined the prescriptions for tonifying kidney and inducing ovulation, which have a remarkable clinical efficacy.


Assuntos
Medicamentos de Ervas Chinesas , Hiperprolactinemia , Infertilidade Feminina , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Hiperprolactinemia/tratamento farmacológico , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/etiologia , Rim , Medicina Tradicional Chinesa
12.
Mitochondrial DNA B Resour ; 6(3): 983-984, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33796708

RESUMO

The first complete chloroplast genome (cp) of Sinosenecio jishouensis D.G. Zhang, Ying Liu & Q. E. Yang (Asteraceae) was sequenced and assembled in this study. The cp genome was 151,257 bp in length, including a large single-copy(LSC) region of 83,373 bp, a small single-copy (SSC) region of 18,178 bp, and a pair of inverted repeat (IR) regions of 24,853 bp each. These sequences encoded 134 genes, including 89 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The phylogenetic analysis based on 18 complete cp sequences revealed that S. jishouensis was closely related to Eclipta prostrata.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-942532

RESUMO

Objective: To evaluate the value of the age-adjusted Charlson comorbidity Index (ACCI) in predicting the prognosis and guiding the clinical treatment of laryngeal squamous cell carcinoma (LSCC) in patients over 60 years old. Methods: Retrospective analysis of 249 cases of LSCC in Shanxi Provincial Cancer Hospital and First Hospital of Shanxi Medical University from 2008 to 2015 was performed. There were 234 males and 15 females, aged from 60 to 88 years. The clinical characteristics, treatment information and follow-up data were collected. ACCI was used to score the comorbidities of the patients. Receiver operating characteristic (ROC) curve was drawn and the patients were divided into high ACCI group and low ACCI group according to the cut-off value of ACCI. Prognostic factors were analyzed. Kaplan-Meier method was used for survival analysis, rank sum test was used for comparison between groups, χ2 test was used for enumeration data. Results: Overall survival (OS) was 54.6%, progression-free survival (PFS) was 59.4%, and cancer-specific survival (CSS) was 58.6%. Both the median survival time and PFS time were 60 months. The best cutoff point of the ACCI group was 5. Cox multivariate analysis showed that ACCI was an independent risk factor for OS, PFS and CSS (OR=1.553, 1.499 and 1.534,respectively, all P<0.05). In the high ACCI group, OS (χ2=4.120 and 4.115,P<0.05) and CSS (χ2=4.510 and 5.009,P<0.05) of patients treated with surgery plus radiotherapy and patients with radiotherapy alone were better than those of patients with surgery alone (P<0.05). But in the low ACCI group, there was no significant difference in prognosis among the three treatment regimens (P>0.05). Conclusion: High ACCI offors important prognostic information for LSCC in patients over 60 years old, and can guide clinical treatment options.


Assuntos
Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Etários , Comorbidade , Neoplasias de Cabeça e Pescoço , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-887931

RESUMO

Hyperprolactinemia(HPRL) is one of the diseases leading to anovulatory infertility, which is a refractory gynecological disease and seriously affects female reproductive function. Professor MA Kun has summarized his experience in clinical and scientific studies for many years. And believes that kidney deficiency is the pathogenesis of HPRL and blood stasis is the dominant pathological manifestation of HPRL and can promote the progress of the disease. In view of this, Professor MA Kun took the therapy of kidney-tonifying and blood-activating as the principle for treating anovulatory infertility caused by HPRL, with soothing the liver and promoting Qi as adjuvant therapies. She has also summarized and refined the prescriptions for tonifying kidney and inducing ovulation, which have a remarkable clinical efficacy.


Assuntos
Feminino , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Hiperprolactinemia/tratamento farmacológico , Infertilidade Feminina/etiologia , Rim , Medicina Tradicional Chinesa
15.
Zhongguo Zhong Yao Za Zhi ; 45(17): 4099-4111, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33164394

RESUMO

The aim of this paper was to explore the mechanism of Xiaoyao Powder in treating atherosclerosis and depressive disorder with concept of "treating different diseases with same method" based on network pharmacology. TCMSP(Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform) and SymMap databases were used to search all the chemical components and targets related to Xiaoyao Powder. After preliminary screening, the network of "herbs-compounds-targets" was constructed. Through DisGeNET, CTD(Comparative Toxicogenomics Database) and TTD(Therapeutic Target Database), the targets of atherosclerosis and depressive disorder were obtained. The common targets were obtained by intersecting the herbal targets and disease targets. In order to screen the key common targets, STRING and Cytoscape were used to analyze the protein-protein interaction of common targets. BioGPS was used to obtain their distribution information in organs and tissues. Gene ontology(GO) and Kyoto encyclopedia of genes and genomes(KEGG) analysis were conducted through Metascape. About 1 355 compounds of Xiaoyao Powder were found by TCMSP and Symmap database; 161 active compounds were screened out according to standard of oral bioavailability≥30% and drug like index≥0.18; 274 herbal targets were obtained and the "herbs-compounds-targets" network was constructed. About 1 004 atherosclerosis targets and 578 depressive disorder targets were obtained, and 37 common targets were obtained after intersection with herbal targets. By using STRING and Cytoscape for protein-protein interaction analysis, 18 key targets were screened. BioGPS showed that the key common targets were mainly distributed in heart, amygdala, pineal, liver and smooth muscle. Metascape was used for GO enrichment analysis and the results showed that there were 929 biological processes, 25 cell components and 23 molecular functions. Enrichment ana-lysis of KEGG showed that there were 108 signal pathways such as AGE-RAGE, HIF-1, FoxO, Th17 cell differentiation and IL-17 signal pathways, which were mainly related to neuroendocrine system, metabolism, immune inflammation and oxidative stress. In conclusion, the main mechanism of Xiaoyao Powder in treating atherosclerosis and depressive disorder with concept of "treating different diseases with same method" was related to neuroendocrine system, metabolism, immune inflammation and oxidative stress-related signal pathway, providing reference for further experimental verification, potential pharmacological mechanism and clinical application.


Assuntos
Aterosclerose , Transtorno Depressivo , Medicamentos de Ervas Chinesas , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Humanos , Medicina Tradicional Chinesa
16.
PLoS One ; 15(6): e0234869, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579578

RESUMO

The continuous variation of the seasonal influenza viruses, particularly A(H1N1)pdm09, persistently threatens human life and health around the world. In local areas of southwest china, the large time-scale genomic research on A(H1N1)pdm09 is still insufficient. Here, we sequenced 45 whole-genome sequences of influenza A(H1N1)pdm09 viruses in Lincang, China, from 2014 to 2018, by next-generation sequencing technology to characterize molecular mechanisms of their origin and evolution. Our phylogenetic analyses suggest that the A(H1N1)pdm09 strains circulating in Lincang belong to clade 6B and the subclade 6B.1A predominates in 2018. Further, the strains in 2018 possess elevated evolutionary rate as compared to strains in other years. Several newly emerged mutations for HA (hemagglutinin) in 2018 are revealed (i.e., S183P and R221K). Intriguingly, the substitution R221K falls into the RBS (receptor binding site) of HA protein, which could affect antigenic properties of influenza A(H1N1)pdm09 viruses, and another substitution S183P near to RBS with a high covering frequency (11/14 strains) in 2018 is exactly located at the epitope B. Notably, the NA (neuraminidase) protein harbors a new mutation I23T, potentially involved in N-glycosylation. Based on the background with a higher evolutionary rate in 2018 strains, we deeply evaluate the potential vaccine efficacy against Lincang strains and discover a substantive decline of the vaccine efficacy in 2018. Our analyses reaffirm that the real-time molecular surveillance and timely updated vaccine strains for prevention and control of influenza A(H1N1)pdm09 are crucial in the future.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H1N1/genética , Sequenciamento Completo do Genoma , Sequência de Aminoácidos , China , Análise Mutacional de DNA , Demografia , Epitopos/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vacinas contra Influenza/imunologia , Mutação/genética , Neuraminidase/genética , Filogenia , Resultado do Tratamento
17.
J Phys Chem Lett ; 11(8): 3051-3057, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32223246

RESUMO

The dissolution of transition-metal (TM) cations into a liquid electrolyte from cathode material, such as Mn ion dissolution from LiMn2O4 (LMO), is detrimental to the cycling performance of Li-ion batteries (LIBs). Though much attention has been paid to this issue, the behavior of Mn dissolution has not been clearly revealed. In this work, by using a refined in situ ultraviolet-visible (UV-vis) spectroscopy technique, we monitored the concentration changes of dissolved Mn ions in liquid electrolyte from LMO at different state of charge (SOC), confirming the maximum dissolution concentration and rate at 4.3 V charged state and Mn2+ as the main species in the electrolyte. Through ab initio molecular dynamics (AIMD) simulations, we revealed that the Mn dissolution process is highly related to surface structure evolution, solvent decomposition, and lithium salt. These results will contribute to understanding TM dissolution mechanisms at working conditions as well as the design of stable cathodes.

18.
Int J Infect Dis ; 96: 452-453, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32194239

RESUMO

We report a familial cluster of 2019 novel coronavirus disease (COVID-19) to assess its potential transmission during the incubation period. The first patient in this familial cluster was identified during the presymptomatic period, as a close contact of a confirmed patient. Five family members had close contact with this first patient during his incubation period, with four of them confirmed positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the subsequent sampling tests.


Assuntos
Betacoronavirus , Infecções por Coronavirus/transmissão , Período de Incubação de Doenças Infecciosas , Pneumonia Viral/transmissão , Adulto , Idoso , COVID-19 , Criança , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
19.
Emerg Infect Dis ; 26(6): 1337-1339, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32150527

RESUMO

We report an asymptomatic child who was positive for a coronavirus by reverse transcription PCR in a stool specimen 17 days after the last virus exposure. The child was virus positive in stool specimens for at least an additional 9 days. Respiratory tract specimens were negative by reverse transcription PCR.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Fezes/virologia , Pneumonia Viral/diagnóstico , RNA Viral/isolamento & purificação , COVID-19 , Criança , Humanos , Masculino , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2
20.
ACS Appl Mater Interfaces ; 12(2): 2319-2326, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31872999

RESUMO

Cathode electrolyte interphase (CEI) layer plays an essential role in determining the electrochemical performance of Li-ion batteries (LIBs), but the detailed mechanisms of CEI formation and evolution are not yet fully understood. With the pursuit of LIBs possessing a high energy density, fundamental investigations on the CEI have become increasingly important. Herein, X-ray photoelectron spectroscopy (XPS) is employed to fingerprint CEI formation and evolution on three of the most prevailing high-voltage cathodes including layered Li1.144Ni0.136Co0.136Mn0.544O2 (LR-NCM), Li2Ru0.5Mn0.5O3 (LRMO), and spinel LiNi0.5Mn1.5O4 (LNMO). The influences of crystal structure, chemical constitution and cut-off voltage on CEI composition are clarified. Among these cathodes, the spinel cathode exhibits the most stable CEI layer throughout the battery cycle. While the layered cathodes based on the 4d transition metal Ru favor CEI formation upon contacting the electrolyte. Most importantly, anionic redox reaction (ARR) activation at high voltages is verified to dominate CEI evolution in subsequent cycles. The distinct CEI behaviors in diverse cathodes can be attributed to a series of entangled processes, including electrolyte/Li salt decomposition, CEI component dissociation and dissociated CEI species redeposition. Based on these findings, rational guidelines are provided for the interface design of high-voltage LIBs.

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