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1.
Proc Natl Acad Sci U S A ; 119(51): e2211436119, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36512500

RESUMO

Electric vehicles (EVs) are imposing ever-challenging standards on the lifetime and safety of lithium-ion batteries (LIBs); consequently, real-time nondestructive monitoring of battery cell degradation is highly desired. Unfortunately, high-nickel (Ni) layered oxides, the preferred LIB cathodes for EVs, undergo performance degradation originating from microcrack formation during cycling. Entropymetry is introduced as a real-time analytic tool for monitoring the evolution of microcracks in these cathodes along the state of charge. The entropy change of the layered cathode is associated with the lattice configuration and reflects the structural heterogeneity relevant to the evolution of these microcracks. The structural heterogeneity was correlated with peak broadening in in-situ X-ray diffractometry while varying the experimental conditions that affect crack formation such as the upper cutoff voltage during charging and the Ni-content of the active material. Entropymetry, proposed here as a nondestructive diagnostic tool, can contribute greatly to the safe and reliable operation of LIBs for EVs.

2.
Chem Soc Rev ; 53(17): 8878-8902, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39106108

RESUMO

The inherent limitations of lithium (Li)-ion batteries have sparked interest in exploring alternative technologies, especially those relying on metallic anodes: monovalent Li and divalent zinc (Zn), magnesium (Mg), and calcium (Ca) metals. In particular, Mg and Ca metal batteries offer significant advantages based on the natural abundance of their raw materials and high energy-storage capabilities resulting from the bivalency of the carrier ions. Yet, these battery systems are far from commercialization, and the lack of reliable electrolytes constitutes a primary concern. The formation of ion-insulating passivation layers on these metallic anodes and their inferior desolvation kinetics have long been recognized as formidable hurdles in the way of optimizing the electrolyte composition. These impediments call for innovative strategies in electrolyte engineering and an extensive analysis of the resulting solid-electrolyte-interphase (SEI) layer. In this review, we introduce recent pioneering studies of divalent Mg and Ca metal batteries that have been concerned with these issues. This review particularly focuses on drawing an analogy with Li and Zn metal batteries in terms of the relative advancement and by benchmarking against the strategies developed for these analogous systems. The areas of interest include a fundamental understanding of the thermodynamics and evolution of the morphology of metallic anodes, a correlation between the electrolyte and SEI compositions, state-of-the-art electrolyte strategies to realize reversible (de)plating of Mg and Ca, and new perspectives on the SEI properties and their relevance to corrosion and the calendar life. We finally encourage researchers in the community to delve into these emerging areas by linking with successful stories in the analogous systems, but identifying distinct aspects of Mg and Ca batteries that still require attention.

3.
J Korean Med Sci ; 39(15): e146, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38651226

RESUMO

In the 2023-2024 season, the influenza epidemic in South Korea peaked earlier than in recent years. In this study, we aimed to estimate the interim vaccine effectiveness (VE) of the influenza vaccination to prevent influenza during the early season. From November 1, 2023, to December 31, 2023, we enrolled 2,632 subjects with influenza-like illness from eight hospitals participating in hospital-based influenza morbidity and mortality surveillance. A retrospective test-negative case-control study was conducted to estimate the VE. The results showed an adjusted VE of 22.5% (95% confidence interval [CI], 6.6 to 35.8) for the total population. The adjusted VE was 22.3% (95% CI, 6.1 to 35.7) for influenza A and 9.4% (95% CI, -51.3 to 45.7) for influenza A/H1N1. Full results of the analysis will be reported.


Assuntos
Vacinas contra Influenza , Influenza Humana , Estações do Ano , Humanos , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , República da Coreia/epidemiologia , Adulto , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Estudos de Casos e Controles , Vírus da Influenza A Subtipo H1N1/imunologia , Adulto Jovem , Eficácia de Vacinas , Vacinação
4.
J Korean Med Sci ; 39(3): e15, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258360

RESUMO

BACKGROUND: Bivalent booster mRNA vaccines containing the omicron-variant strains have been introduced worldwide in the autumn of 2022. Nevertheless, the omicron subvariants evoked another large coronavirus disease 2019 (COVID-19) pandemic wave in late 2022 and early 2023. METHODS: A retrospective, test-negative, case-control study was conducted to estimate the vaccine effectiveness (VE) of bivalent COVID-19 vaccines in 8 university hospitals between January and February 2023. The case and control groups were divided based on nasopharyngeal COVID-19 real-time polymerase chain reaction results and matched based on age, sex, hospital, and date (week) of the test performed. The VE of the BA.1- or BA.4/BA.5-based mRNA vaccines were estimated. VE was calculated using the 1-adjusted odds ratio from multivariable logistic regression. RESULTS: In total, 949 patients and 947 controls were enrolled in this study. VE for the BA.4/BA.5-based bivalent mRNA vaccine was 43% (95% confidence interval [CI], 17, 61%). In subgroup analysis based on age and underlying medical conditions, BA.4/BA.5-based bivalent mRNA vaccine was effective against old adults aged ≥ 65-years (VE, 55%; 95% CI, 23, 73%) and individuals with comorbidities (VE, 54%; 95% CI, 23, 73%). In comparison, the BA.1-based bivalent mRNA vaccine did not demonstrate statistically significant effectiveness (VE, 25%; 95% CI, -8, 49%). CONCLUSION: The BA.4/BA.5-based bivalent mRNA booster vaccine provided significant protection against COVID-19 in the Korean adults, especially in the older adults aged ≥ 65 years and in individuals with underlying medical conditions.


Assuntos
COVID-19 , Humanos , Idoso , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos de Casos e Controles , Estudos Retrospectivos , Vacinas de mRNA , Hospitais Universitários , RNA Mensageiro/genética , República da Coreia/epidemiologia
5.
Eur Arch Otorhinolaryngol ; 281(9): 4719-4725, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38700539

RESUMO

PURPOSE: Facial nerve schwannomas (FNSs) are rare intracranial tumors, and the optimal management of these tumors remains unclear. We investigated the long-term follow-up results of FNS with good facial nerve function. METHODS: At nine medical centers in the Korean Facial Nerve Study Group, 43 patients undergoing observation periods longer than 12 months for FNS with good facial nerve function (House-Brackmann grade ≤ II) were enrolled, and clinical and radiographic data were obtained for these cases. RESULTS: The mean follow-up period was 63 months. In the majority of cases, tumors involved multiple segments (81.4%) and only eight cases were confined to a single site. There were no cases where the tumor was confined to the extratemporal region. Tumor size increased slightly, with an average estimated change of 0.48 mm/year. Twenty (46.5%) of 43 patients showed no change in tumor size. Seven patients (16.3%) showed worsening House-Brackmann (H-B) grade, of which two patients deteriorated from H-B grade I to II, four worsened to grade III, and one deteriorated to grade IV. The remaining 36 patients (83.7%) showed no change in facial nerve function. There was no difference in H-B grade according to tumor size at the time of diagnosis or change in tumor size. CONCLUSION: We conducted a large-scale observational study of FNS with good facial nerve function. Our study showed that many patients maintained facial nerve function during long-term follow-up. Conservative management with regular examination and imaging can be an appropriate option for managing FNS with good facial nerve function.


Assuntos
Neoplasias dos Nervos Cranianos , Neurilemoma , Humanos , Neurilemoma/cirurgia , Neurilemoma/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Seguimentos , Idoso , Nervo Facial/fisiopatologia , Doenças do Nervo Facial/fisiopatologia , Adulto Jovem , Adolescente , Imageamento por Ressonância Magnética , Estudos Retrospectivos
6.
Angew Chem Int Ed Engl ; 63(35): e202408238, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860886

RESUMO

Sulfide-based all-solid-state battery (ASSB) with a lithium metal anode (LMA) is a promising candidate to surpass conventional Li-ion batteries owing to their inherent safety against fire hazards and potential to achieve a higher energy density. However, the narrow electrochemical stability window and chemical reactivity of the sulfide solid electrolyte towards the LMA results in interfacial degradation and poor electrochemical performance. In this direction, we introduce an organic additive approach, that is the mixing of prelithiated trithiocyanuric acid, Li3TCA, with Li6PS5Cl, to establish a stable interface while preserving high ionic conductivity. Including 2.5 wt % Li3TCA alleviates the decomposition of the electrolyte on the lithium metal interface, decreasing the Li2S content in the solid-electrolyte interface (SEI) thus forming a more stable interface. In Li|Li symmetric cells, this strategy enables a rise in the critical current density from 1.0 to 1.9 mA cm-2 and stable cycling for over 750 hours at a high current density of 1.0 mA cm-2. This approach also enables Li|NbO-NCM811 full cell to operate more than 500 cycles at 0.3 C.

7.
J Am Chem Soc ; 145(29): 15776-15787, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37436721

RESUMO

Aqueous zinc-ion batteries (AZIBs) are receiving increasing attention for power-grid energy storage systems. Nevertheless, warranting long-term reversible operation is not trivial owing to uncontrolled interfacial phenomena related to zinc dendritic growth and parasitic reactions. Herein, the addition of hexamethylphosphoramide (HMPA) to the electrolyte revealed the surface overpotential (|ηs|) to be a key metric of the reversibility. HMPA adsorbs onto active sites on the zinc metal surface, raising the surface overpotential toward lowering the nucleation energy barrier and decreasing the critical size (rcrit) of nuclei. We also correlated the observed interface-to-bulk properties by the Wagner (Wa) dimensionless number. The controlled interface enables a Zn|V6O13 full cell to retain 75.97% capacity for 2000 cycles, with a capacity loss of only 1.5% after 72 h resting. Our study not only delivers AZIBs with unparalleled cycling and storage performance but also proposes surface overpotential as a key descriptor regarding the sustainability of AZIB cycling and storage.

8.
Epidemiol Infect ; 151: e180, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814587

RESUMO

The aim of this study was to evaluate the impact of coronavirus disease 2019 (COVID-19) on treatment outcomes in critically ill patients with carbapenem-resistant Acinetobacter baumannii (CRAB) bloodstream infection (BSI). This single-centre, retrospective cohort study was conducted in a 1,048-bed university-affiliated tertiary hospital in the Republic of Korea from January 2021 to March 2022. The study participants included consecutive hospitalised adult patients (aged ≥18 years) in the intensive care unit with CRAB monomicrobial BSI. During the study period, a total of 70 patients were included in our study, and 24 (34.3%) were diagnosed with COVID-19. The 28-day mortality rate was 64.3%. In the multivariate Cox proportional hazard regression analysis, diagnosis of COVID-19 (hazard ratio (HR), 2.91; 95% confidence interval (CI): 1.45-5.87), neutropenia (HR, 2.76; 95% CI: 1.04-7.29), Pitt bacteraemia score (per point; HR, 1.30; 95% CI: 1.19-1.41), and appropriate definite antibiotic therapy (HR, 0.31; 95% CI: 0.15-0.62) were independent predictors of 28-day mortality in patients with CRAB BSI. In conclusion, our findings suggested that COVID-19 has a negative prognostic impact on patients with CRAB BSI. Further study is needed to investigate the specific mechanisms of how COVID-19 worsens the prognosis of CRAB infection.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Bacteriemia , COVID-19 , Adulto , Humanos , Adolescente , Estudos Retrospectivos , Carbapenêmicos/uso terapêutico , Infecções por Acinetobacter/tratamento farmacológico , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico
9.
BMC Geriatr ; 23(1): 127, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879198

RESUMO

BACKGROUND: This study aimed to develop and validate a clinical prediction rule to screen older patients at risk of being toxigenic Clostridioides difficile carriers at the time of hospital admission. METHODS: This retrospective case-control study was performed at a university-affiliated hospital. Active surveillance using a real-time polymerase chain reaction (PCR) assay for the toxin genes of C. difficile was conducted among older patients (≥ 65 years) upon admission to the Division of Infectious Diseases of our institution. This rule was drawn from a derivative cohort between October 2019 and April 2021 using a multivariable logistic regression model. Clinical predictability was evaluated in the validation cohort between May 2021 and October 2021. RESULTS: Of 628 PCR screenings for toxigenic C. difficile carriage, 101 (16.1%) yielded positive findings. To establish clinical prediction rules in the derivation cohort, the formula was derived using significant predictors for toxigenic C. difficile carriage at admission, such as septic shock, connective tissue diseases, anemia, recent use of antibiotics, and recent use of proton-pump inhibitors. In the validation cohort, the sensitivity, specificity, and positive and negative predictive values of the prediction rule, based on a cut-off value of ≥ 0.45, were 78.3%, 70.8%, 29.5%, and 95.4%, respectively. CONCLUSION: This clinical prediction rule for identifying toxigenic C. difficile carriage at admission may facilitate the selective screening of high-risk groups. To implement it in a clinical setting, more patients from other medical institutions need to be prospectively examined.


Assuntos
Regras de Decisão Clínica , Clostridioides difficile , Humanos , Estudos de Casos e Controles , Estudos Retrospectivos , Hospitais Universitários
10.
Sensors (Basel) ; 23(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36679806

RESUMO

Industry 5.0, also known as the "smart factory", is an evolution of manufacturing technology that utilizes advanced data analytics and machine learning techniques to optimize production processes. One key aspect of Industry 5.0 is using vibration data to monitor and detect anomalies in machinery and equipment. In the case of a vertical carousel storage and retrieval system (VCSRS), vibration data can be collected and analyzed to identify potential issues with the system's operation. A correlation coefficient model was used to detect anomalies accurately in the vertical carousel system to ascertain the optimal sensor placement position. This model utilized the Fisher information matrix (FIM) and effective independence (EFI) methods to optimize the sensor placement for maximum accuracy and reliability. An LSTM-autoencoder (long short-term memory) model was used for training and testing further to enhance the accuracy of the anomaly detection process. This machine-learning technique allowed for detecting patterns and trends in the vibration data that may not have been evident using traditional methods. The combination of the correlation coefficient model and the LSTM-autoencoder resulted in an accuracy rate of 97.70% for detecting anomalies in the vertical carousel system.


Assuntos
Modalidades de Fisioterapia , Vibração , Reprodutibilidade dos Testes , Comércio , Ciência de Dados
11.
Am J Kidney Dis ; 79(2): 175-184.e1, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34419516

RESUMO

RATIONALE & OBJECTIVE: Although existing studies have reported adverse health outcomes after kidney donation, its socioeconomic impact on living donors requires further study. STUDY DESIGN: A retrospective observational cohort study including a matched comparison group. SETTING & PARTICIPANTS: 1,285 living kidney donors from 7 tertiary hospitals between 2003 and 2016, and a matched comparison group consisting of the same number of health screening examinees with similar baseline clinical characteristics and socioeconomic status. All participants were receiving Korean national health insurance. EXPOSURE: Kidney donation as reflected in the Korean National Health Insurance System (NHIS) database. OUTCOME: Changes in household economic status estimated by Korean national health insurance fees and changes in employment status reflected in the NHIS database. ANALYTICAL APPROACH: The outcomes of the donor group and matched control group were compared annually using multivariable logistic regression analyses adjusted for clinical and demographic characteristics. RESULTS: The median ages of the donors and matched controls were 45 and 46 years, respectively; 44.6% of both groups were male. Compared to the comparison group, living donors were at higher risk of being unemployed or losing employment during the first 2 years after donation (eg, first-year loss of employment: odds ratio (OR), 2.27 [95% CI, 1.55-3.33]); however, this association did not persist. Donors also had a significantly lower odds of improvement in economic status (OR, 0.57 [95% CI, 0.47-0.71]) and a higher odds of deterioration in financial status (OR, 1.54 [95% CI, 1.23-1.93]) in the first year after transplantation and subsequently. LIMITATIONS: Unmeasured differences between donors and matched controls creating residual selection bias and confounding. CONCLUSIONS: Living kidney donors may suffer loss of employment and poor economic status after their voluntary donation. The socioeconomic impact on these donors should be considered in conjunction with the potential long-term adverse health outcomes after donation.


Assuntos
Transplante de Rim , Doadores Vivos , Estudos de Coortes , Humanos , Rim , Masculino , Pessoa de Meia-Idade , Nefrectomia , República da Coreia/epidemiologia , Estudos Retrospectivos
12.
Acc Chem Res ; 54(17): 3390-3402, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34402619

RESUMO

ConspectusAll-solid-state batteries (ASSBs) are considered to be a next-generation energy storage concept that offers enhanced safety and potentially high energy density. The identification of solid electrolytes (SEs) with high ionic conductivity was the stepping-stone that enabled the recent surge in activity in this research area. Among the various types of SEs, including those based on oxides, sulfides, polymers, and hybrids thereof, sulfide-based SEs have gained discernible attention owing to their exceptional room temperature ionic conductivity comparable even to those of their liquid electrolyte counterparts. Moreover, the good deformability of sulfide SEs renders them suitable for reducing the interfacial resistance between particles, thereby obviating the need for high-temperature sintering. Nevertheless, sulfide-based ASSB technology still remains at the research stage without any manufacturing schemes having been established. This state of affairs originates from the complex challenges presented by various aspects of these SEs: their weak stability in air, questions surrounding the exact combination of slurry solvent and polymeric binder for solution-based electrode fabrication, their high interfacial resistance resulting from solid particle contacts, and limited scalability with respect to electrode fabrication and cell assembly. In this Account, we review recent developments in which these issues were addressed by starting with the materials and moving on to processing, focusing on new trials. As for enhancing the air stability of sulfide SEs, strengthening the metal-sulfur bond based on the hard-soft acid-base (HSAB) theory has yielded the most notable results, although the resulting sacrificed energy density and weakened anode interface stability would need to be resolved. Novel electrode fabrication techniques that endeavor to overcome the critical issues originating from the use of sulfide SEs are subsequently introduced. The wet chemical coating process can take advantage of the know-how and facilities inherited from the more established lithium-ion batteries (LIBs). However, the dilemmatic matter of contention relating to the polarity mismatch among the slurry solvent, SE, and binder requires attention. Recent solutions to these problems involved the exploration of various emerging concepts, such as polarity switching during electrode fabrication, fine polarity tuning by accurate grafting, and infiltration of the electrode voids by a solution of the SE. The process of using a dry film with a fibrous binder has also raised interest, motivated by lowering the manufacturing cost, maintaining the environment, and boosting the volumetric energy density. Finally, optimization of the cell assembly and operation is reviewed. In particular, the application of external pressure to each unit cell has been universally adopted both in the fabrication step and during cell operation to realize high cell performance. The effect of pressurization is discussed by correlating it with the interface stability and robust interparticle contacts. Based on the significant progress that has been made thus far, we aim to encourage the battery community to engage their wide-ranging expertise toward advancing sulfide-based ASSBs that are practically feasible.

13.
Sensors (Basel) ; 22(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35161952

RESUMO

Vibration sensors are mostly used for fault diagnoses of machines or structures. If more sensors are applied, more accurate fault diagnosis is possible. However, it will obviously cost more. There are many approaches to optimize the number and installation location/point of vibration sensors for more efficient fault diagnosis. Existing methods require a great deal of computational throughput for optimization when considering many mode frequencies with points where vibration sensors are likely to be installed. This paper proposes a practical way of optimizing the sensor installation point considering many mode frequencies with lots of places for sensor installation. FEA was conducted to identify displacement values of each frequency in the candidate points. Then, correlation coefficients were applied to the FEA result to optimize the installation location and number of vibration sensors. Taking into account cases where the number of sensors has been set by users, FIM was applied. The correlation coefficient optimized the candidate points where 24,252 vibration sensors were to be installed and reduced this to 10 points. FIM, which was not suitable for directly optimizing sensor locations because it required a lot of computational throughput and was usually applied to evaluate other methods, is now applicable to candidate points that have been reduced by the correlation coefficient. This paper does not draw the best optimal sensor location but presents a way to apply to large-scale or complicated forms with a little computational throughput.


Assuntos
Modalidades de Fisioterapia , Vibração
14.
Angew Chem Int Ed Engl ; 61(19): e202115884, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35274417

RESUMO

Ether-based electrolytes offer promising features such as high lithium-ion solvation power and stable interface, yet their limited oxidation stability impedes application in high-voltage Li-metal batteries (LMBs). Whereas the fluorination of the ether backbone improves the oxidative stability, the resulting solvents lose their Li+ -solvation ability. Therefore, the rational molecular design of solvents is essential to combine high redox stability with good ionic conductivity. Here, we report the synthesis of a new high-voltage fluorinated ether solvent through integrated ring-chain molecular design, which can be used as a single solvent while retaining high-voltage stability. The controlled Li+ -solvation environment even at low-salt-concentration (1 M or 2 M) enables a uniform and compact Li anode and an outstanding cycling stability in the Li|NCM811 full cell (20 µm Li foil, N/P ratio of 4). These results show the impact of molecular design of electrolytes towards the utilization of LMBs.

15.
Angew Chem Int Ed Engl ; 61(47): e202211589, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36180384

RESUMO

Despite substantial progresses, in aqueous zinc ion batteries (AZIBs), developing zinc metal anodes with long-term reliable cycling capabilities is nontrivial because of dendritic growth and related parasitic reactions on the zinc surface. Here, we exploit the tip-blocking effect of a scandium (Sc3+ ) additive in the electrolyte to induce uniform zinc deposition. Additional to the tri-valency of Sc3+ , the rigidity of its hydration shell effectively prevents zinc ions from concentrating at the surface tips, enabling highly stable cycling under challenging conditions. The shell rigidity, quantified by the rate constant of the exchange reaction (kex ), is established as a key descriptor for evaluating the tip-blocking effect of redox-inactive cations, explaining inconsistent results when only the valence state is considered. Moreover, the tip-blocking effect of Sc3+ is maintained in blends with organic solvents, allowing the zinc anode to cycle reliably even at -40 °C without corrosion.

16.
J Am Chem Soc ; 143(42): 17655-17665, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34648256

RESUMO

Supramolecular polymers are compelling platforms for the design of stimuli-responsive materials with emergent functions. Here, we report the assembly of an amphiphilic nanotube for Li-ion conduction that exhibits high ionic conductivity, mechanical integrity, electrochemical stability, and solution processability. Imine condensation of a pyridine-containing diamine with a triethylene glycol functionalized isophthalaldehyde yields pore-functionalized macrocycles. Atomic force microscopy, scanning electron microscopy, and in solvo X-ray diffraction reveal that macrocycle protonation during their mild synthesis drives assembly into high-aspect ratio (>103) nanotubes with three interior triethylene glycol groups. Electrochemical impedance spectroscopy demonstrates that lithiated nanotubes are efficient Li+ conductors, with an activation energy of 0.42 eV and a peak room temperature conductivity of 3.91 ± 0.38 × 10-5 S cm-1. 7Li NMR and Raman spectroscopy show that lithiation occurs exclusively within the nanotube interior and implicates the glycol groups in facilitating efficient Li+ transduction. Linear sweep voltammetry and galvanostatic lithium plating-stripping tests reveal that this nanotube-based electrolyte is stable over a wide potential range and supports long-term cyclability. These findings demonstrate how the coupling of synthetic design and supramolecular structural control can yield high-performance ionic transporters that are amenable to device-relevant fabrication, as well as the technological potential of chemically designed self-assembled nanotubes.

17.
BMC Infect Dis ; 21(1): 229, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33639861

RESUMO

BACKGROUND: The massive outbreak of the novel coronavirus disease 2019 (COVID-19) in Daegu city and Gyeongsangbuk-do, Republic of Korea (ROK), caused the exponential increase in new cases exceeding 5000 within 6 weeks. Therefore, the community treatment center (CTC) with a digital health care monitoring system based on the smartphone application and personal health record platform (PHR) was implemented. Thus, we report our experience in one of the CTCs to investigate the role of CTC and the feasibility of the digital health care monitoring system in the COVID-19 pandemic. METHODS: The Gyeongbuk-Daegu 2 CTC was set up at the private residential facility. Admission criteria were 1) patients < 65 years with COVID-19, 2) patients without underlying medical comorbidities, and 3) COVID-19 disease severity of mild class. Admitted patients were placed under monitoring of vital signs and symptoms. Clinical information was collected using the smartphone application or telephone communication. Collected information was displayed on the PHR platform in a real-time fashion for close monitoring. RESULTS: From Mar 3, 2020, to Mar 26, 2020, there was a total of 290 patients admitted to the facility. Males were 104 (35.9%). The median age was 37 years. The median time between the COVID-19 diagnosis and admission was 7 days. Five patients were identified and were transferred to the designed COVID-19 treatment hospital for their urgent medical needs. The smartphone application usage to report vital signs and symptoms was noted in 96% of the patients. There were no deaths of the patients. CONCLUSIONS: Our results suggest that implementation of the CTC using a commercial residence facility and digital health care technology may offer valuable solutions to the challenges posed by the COVID-19 outbreak.


Assuntos
Tratamento Farmacológico da COVID-19 , Atenção à Saúde , Registros de Saúde Pessoal , SARS-CoV-2 , Smartphone , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Korean Med Sci ; 36(15): e110, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33876589

RESUMO

Hospital-based surveillance for adverse events was conducted on healthcare workers after they received the first dose of coronavirus disease 2019 (COVID-19) vaccine. Among the two new platform vaccines (messenger RNA- and adenoviral vector-based vaccines), the rates of systemic adverse events were significantly higher among adenovirus-vectored vaccine recipients. Fatigue (87.6% vs. 53.8%), myalgia (80.8% vs. 50.0%), headache (72.0% vs. 28.8%), and fever (≥ 38.0°C, 38.7% vs. 0%) were the most common adverse events among adenovirus-vectored vaccine recipients, but most symptoms resolved within 2 days. Both types of COVID-19 vaccines were generally safe, and serious adverse events rarely occurred.


Assuntos
Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Pessoal de Saúde , SARS-CoV-2/imunologia , Vacinação/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Angew Chem Int Ed Engl ; 60(42): 22791-22796, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379356

RESUMO

Metallic lithium (Li) is regarded as the ideal anode material in lithium-ion batteries due to its low electrochemical potential, highest theoretical energy density and low density. There are, however, still significant challenges to be addressed such as Li-dendrite growth and low interfacial stability, which impede the practical application of Li metal anodes. In order to circumvent these shortcomings, herein, we present a gel polymer electrolyte containing imidazolium ionic liquid end groups with a perfluorinated alkyl chain (F-IL) to achieve both high ionic conductivity and Li ion transference number by fundamentally altering the solubility of salt within the gel electrolyte through Lewis-acidic segments in the polymer backbone. Moreover, the presence of F-IL moieties decreased the binding affinity of Li cation towards the glycol chains, enabling a rapid transfer of Li cation within the gel network. These structural features enabled the immobilization of anions on the ionic liquid segments to alleviate the space-charge effect while promoting stronger anion coordination and weaker cation coordination in the Lewis-acidic polymers. Accordingly, we realized a high Li ion conductivity (9.16×10-3  S cm-1 ) and high Li ion transference number of 0.69 simultaneously, along with a good electrochemical stability up to 4.55 V, while effectively suppressing Li dendrite growth. Moreover, the gel polymer electrolyte exhibited stable cycling performance of the Li|Li symmetric cell of 9 mAh cm-2 for more than 1800 hours and retained 86.7 % of the original capacity after 250 cycles for lithium-sulfur (Li-S) full cell.

20.
Emerg Infect Dis ; 26(10): 2338-2345, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32568663

RESUMO

As a part of measures to decrease spikes in coronavirus disease (COVID-19) cases and deaths outside of hospitals, the government of South Korea introduced a plan for community treatment centers (CTCs) to isolate and monitor patients with mild COVID-19 symptoms. We assessed outcomes of 568 patients admitted to 3 CTCs near Daegu. More (64.6%) women than men (35.4%) were admitted, and the mean age of patients was 36.0 years (SD +15.0 years). Among all patients, 75.7% remained asymptomatic while at the CTCs. The mean time patients remained at CTCs was 19.6 days (SD +5.8 days) from the day of diagnosis until our study ended on March 23, 2020. Because they offer appropriate clinical triaging and daily monitoring for patients, CTCs are a safe alternative to medical institutions for asymptomatic or mildly symptomatic patients with COVID-19.


Assuntos
Centros Comunitários de Saúde/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Isolamento de Pacientes/métodos , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Adulto , Idoso , Infecções Assintomáticas , Betacoronavirus/isolamento & purificação , COVID-19 , Pré-Escolar , Centros Comunitários de Saúde/organização & administração , Comorbidade , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Transferência de Pacientes , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/estatística & dados numéricos , República da Coreia/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/estatística & dados numéricos , SARS-CoV-2
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