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1.
Nutrients ; 16(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38674898

RESUMO

Child malnutrition remains a public health challenge in developing countries, but a comprehensive understanding of its burden and its determinants in specific local contexts is generally lacking. This study examined the prevalence of malnutrition and its determinants among children aged <5 years across contrasting agroecosystems in northwest Ethiopia. A community-based cross-sectional study involving 400 respondents was employed. Data were collected through semi-structured questionnaires and anthropometric measurements, complemented with focus group discussions and key informant interviews. The direct and indirect effects of the determinants of malnutrition were examined using structural equation modeling (SEM). The overall prevalence of child malnutrition, measured using the Composite Index of Anthropometric Failure, was 49%, with notable variation across agroecosystems (from 36.1% [midland with red soil] to 59% [lowland and valley fragmented]). Disease experience had significant positive direct effects on malnutrition. Dietary intake had negative and significant total (direct and indirect) effects on malnutrition, partially mediated through disease experience. Serial mediation in SEM analysis revealed significant indirect relationships between malnutrition and food security, feeding and care practices, household environment, health services, maternal diet, maternal empowerment, household wealth, and nutrition-sensitive agricultural practices. In conclusion, child malnutrition was highly prevalent and higher among children in the lowland and valley fragmented agroecosystem, characterized by unfavorable agro-climatic conditions, lower wealth status, poor health services access, and higher disease (particularly malaria) exposure. This study demonstrates the dynamics and multifaceted nature of malnutrition, highlighting the importance of considering geographical differences when planning interventions for childhood malnutrition and its determinants.


Assuntos
Transtornos da Nutrição Infantil , Humanos , Etiópia/epidemiologia , Pré-Escolar , Feminino , Masculino , Estudos Transversais , Transtornos da Nutrição Infantil/epidemiologia , Lactente , Prevalência , Análise de Classes Latentes , Agricultura , Fatores Socioeconômicos , Estado Nutricional , Antropometria
2.
Sci Rep ; 14(1): 8521, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609457

RESUMO

Quadratic Phase Coupling (QPC) serves as an essential statistical instrument for evaluating nonlinear synchronization within multivariate time series data, especially in signal processing and neuroscience fields. This study explores the precision of QPC detection using numerical estimates derived from cross-bicoherence and bivariate Granger causality within a straightforward, yet noisy, instantaneous multiplier model. It further assesses the impact of accidental statistically significant bifrequency interactions, introducing new metrics such as the ratio of bispectral quadratic phase coupling and the ratio of bivariate Granger causality quadratic phase coupling. Ratios nearing 1 signify a high degree of accuracy in detecting QPC. The coupling strength between interacting channels is identified as a key element that introduces nonlinearities, influencing the signal-to-noise ratio in the output channel. The model is tested across 59 experimental conditions of simulated recordings, with each condition evaluated against six coupling strength values, covering a wide range of carrier frequencies to examine a broad spectrum of scenarios. The findings demonstrate that the bispectral method outperforms bivariate Granger causality, particularly in identifying specific QPC under conditions of very weak couplings and in the presence of noise. The detection of specific QPC is crucial for neuroscience applications aimed at better understanding the temporal and spatial coordination between different brain regions.

3.
Am J Disaster Med ; 18(1): 17-30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970696

RESUMO

OBJECTIVE: We aimed to clarify the characteristics of patients consulted by the medical staff with emergency medicine (EM) physicians after vaccination and EM physicians transferred to an outside hospital. DESIGN: The Japanese Self-Defense Force established a large-scale coronavirus disease 2019 (COVID-19) vaccination center. Overall, 1,306,928 citizens received the Moderna vaccine, which targeted the first and second vaccinations between May 24, 2021 and November 30, 2021. EM physicians were always available in the emergency room (ER). The medical staff could consult the patients with EM physicians; however, the criteria were ambiguous. We conducted signal detection analysis on the patients who experienced adverse events to detect characteristics. RESULTS: Of the 3,312 patients experienced adverse events after vaccination, the medical staff consulted 344 with EM physicians. The patients whose respiratory rate and systolic blood pressure (BP) were more than 18 per minute and 162 mmHg, respectively, were considerably consulted. In addition, the patients whose systolic BP was more than 186.5 mmHg were transferred to an outside hospital. No patients were seriously ill or died after being transferred to an outside hospital. CONCLUSIONS: The medical staff consulted the patients with a high respiratory rate or BP with EM physicians. In addition to BP, the respiratory rate would also be necessary as a finding that suggests a patient's severity after vaccination. Therefore, it appears safer that EM physicians are always available to ensure the recipients' safety when running a new large-scale vaccination center against unknown diseases, such as COVID-19.


Assuntos
COVID-19 , Medicina de Emergência , Médicos , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Vacinação , Estudos Prospectivos
6.
Angew Chem Int Ed Engl ; 62(30): e202301416, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37070794

RESUMO

Mixed-anion compounds have attracted growing attentions, but their synthesis is challenging, making a rational search desirable. Here, we explored LaF3 -LaX3 (X=Cl, Br, I) system using ab initio structure searches based on evolutionary algorithms, and predicted LaF2 X and LaFX2 (X=Br, I), which are respectively isostructural with LaHBr2 and YH2 I, consisting of layered La-F blocks with single and double ordered honeycomb lattices, separated by van der Waals gaps. We successfully synthesized these compounds: LaF2 Br and LaFI2 crystallize in the predicted structure, while LaF2 I is similar to the predicted one but with different layer stacking. LaF2 I exhibits fluoride ion conductivity comparable to that of non-doped LaF3 , and has the potential to show better ionic conductivity upon appropriate doping, given the theoretically lower diffusion energy barrier and the presence of soft iodine anions. This study shows the structure prediction using evolutionary algorithms will accelerate the discovery of mixed-anion compounds in future, in particular those with an ordered anion arrangement.

7.
Clin Pharmacol Ther ; 113(5): 1117-1124, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36752635

RESUMO

The utility of big data in spontaneous adverse drug reactions (ADRs) reporting systems has improved the pharmacovigilance process. However, identifying culprit drugs in ADRs remains challenging, although it is one of the foremost steps to managing ADRs. Aiming to estimate the likelihood of prescribed drugs being culprit drugs for given ADRs, we devised a Bayesian estimation model based on the Japanese Adverse Drug Events Reports database. After developing the model, a validation study was conducted with 67 ADR reports with a gross of 1,387 drugs (67 culprit drugs and 1,320 concomitant drugs) prescribed and recorded at Yamaguchi University Hospital. As a result, the model estimated a culprit drug of ADRs with acceptable accuracy (area under the receiver operating characteristic curve 0.93 (95% confidence interval 0.88-0.97)). The estimation results provided by the model to healthcare practitioners can be used as one clue to determine the culprit drugs for various ADRs, which will improve the management of ADRs by shortening the treatment turnaround time and increasing the precision of diagnosis, leading to minimizing the adverse effects on patients.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Teorema de Bayes , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Farmacovigilância , Bases de Dados Factuais
8.
Chemphyschem ; 24(5): e202200527, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436830

RESUMO

An oligo/poly(methyl(2-(tris(2-H methoxyethoxy)silyl)ethyl)siloxane)), 390EO, and 2550EO, were synthesized. Dilute electrolyte solutions of 390EO and 2550EO were prepared using LiTFSI, LiFSI, and LiPF6 . The influence of the length of the siloxane polymer chain, salt type, and Si-tripodand centers at the side chain on ionic conductivity, tLi + , and physical properties were examined. Both electrolyte systems showed high values of tLi + (0.35 for 2550EO/LiTFSI and 0.64 for 390EO/LiTFSI). Alternatively 390EO/LiPF6 and 2550EO/LiPF6 displayed high tLi + values of 0.61 and 0.44, respectively, while 390EO/LiFSI displayed the smallest tLi+ (0.25). To clarify the role played by the Li+ environment in Li+ transport, the solvation states of electrolytes were examined. It was observed that anion solvation can be achieved using siloxane-based solvent in all systems. Walden plot analysis demonstrates that ionic diffusion was not controlled by either macroviscosity/microviscosity in the siloxane-based polymer electrolytes. Ions instead move along a relatively smooth ion-pathway without complete full segmental reorientation in 2550EO as a result of decoupling and high ion solvation behavior. Conversely, in 390EO, ions might move to available sites by a jumping after decoupling with low ion solvation behavior. Consequently, a high t Li + was achieved, and the oxidative stability of the salt was ensured.

9.
ChemSusChem ; 16(4): e202201569, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36107028

RESUMO

Graphite intercalation compounds (GICs) of anions have attracted much attention as a positive electrode for use in dual-ion batteries. In this study, GICs of bis(trifluoromethanesulfonyl)amide (TFSA) anions were electrochemically synthesized in ionic liquids with lithium or magnesium salts to investigate the kinetics of GICs formation. By varying the concentrations of LiTFSA or Mg(TFSA)2 , the activation energy of interfacial anion transfer resistance was discovered to be correlated with the viscosity of the ionic liquid electrolytes. Such a change in activation energy is unique to ionic liquids and not seen in common molecular solvent electrolytes. In addition, ionic liquids with nearly identical viscosities exhibited similar resistances and activation energies. The relationship between the viscosity of ionic liquids and the kinetic parameters of interfacial anion transfer found in this study provides important insights for the construction of dual-ion batteries that aim for both high capacity and high rate capability.

10.
ACS Appl Mater Interfaces ; 14(36): 40881-40889, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35984969

RESUMO

Solid-state Li-metal batteries have the potential to achieve both high safety and high energy densities. Among various solid-state fast-ion conductors, the garnet-type Li7La3Zr2O12 (LLZO) is one of the few that are stable to Li metal. However, the large interfacial resistance between LLZO and cathode materials severely limits the practical application of LLZO. Here a LiCoO2 (LCO) film was deposited onto an Al-doped LLZO substrate at room temperature by aerosol deposition, and a low interfacial resistance was achieved. The LCO particles were precoated by Li3BO3 (LBO), which melted to join the LCO particles to the LLZO substrate at heating. All-solid-state Li/LLZO/LBO-LCO cells could deliver an initial discharge capacity of 128 mAh g-1 at 0.2 C and 60 °C and demonstrated relatively high capacity retention of 87% after 30 cycles. The cell degradation mechanism was studied by electrochemical impedance spectroscopy (EIS) and was found to be mainly related to the increase of the interfacial resistance between LBO and LCO. In-situ SEM analysis verified the hypothesis that the increase of the interfacial resistance was caused primarily by interfacial cracking upon cycling. This study demonstrated the capability of EIS as a powerful nondestructive in-situ technique to investigate the failure mechanisms of all-solid-state batteries.

11.
iScience ; 25(3): 103896, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35243254

RESUMO

Although ceramic solid electrolytes, such as Li7La3Zr2O12 (LLZO), are promising candidates to replace conventional liquid electrolytes for developing safe and high-energy-density solid-state Li-metal batteries, the large interfacial resistance between cathodes and ceramic solid electrolytes severely limits their practical application. Here we developed an ionic liquid (IL)-containing while nonfluidic quasi-solid-state LiCoO2 (LCO) composite cathode, which can maintain good contact with an Al-doped LLZO (Al-LLZO) ceramic electrolyte. Accordingly the interfacial resistance between LCO and Al-LLZO was significantly decreased. Quasi-solid-state LCO/Al-LLZO/Li cells demonstrated relatively high capacity retention of about 80% after 100 cycles at 60°C. The capacity decay was mainly because of the instability of the IL. Nevertheless, the IL-containing LCO cathode enabled the use of Al-LLZO as a solid electrolyte in a simple and practical way. Identifying a suitable IL is critical for the development of quasi-solid-state Li-metal batteries with a ceramic solid electrolyte.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35167264

RESUMO

The development of high-rate lithium-ion batteries is required for automobile applications. To this end, internal resistances must be reduced, among which Li+ transfer resistance at electrode/electrolyte interfaces is known to be the largest. Hence, it is of urgent significance to understand the mechanism and kinetics of the interfacial Li+ transfer. This Spotlight on Applications presents recent progress in the analysis and mechanical understanding of interfacial Li+ transfer. First, we review the reported activation energies (Ea) at various solid/liquid interfaces. On this basis, the mechanism and rate-determining step of the interfacial Li+ transfer are discussed from the viewpoints of the desolvation of Li+, the nature of the solid electrolyte interphase (SEI), and the surface structural features of electrodes. After that, we introduce promising strategies to reduce the Ea, highlighting some specific cases that give remarkably low Ea. We also note the variations in frequency factors or pre-exponential factors (A) of the interfacial Li+ transfer, which are primarily dominated by the number of Li+ intercalation sites on electrode surfaces. The current understanding and improvement strategies of interfacial Li+ transfer kinetics presented herein will be a foundation for designing high-rate lithium-ion batteries.

13.
Anal Chem ; 93(45): 15058-15062, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34726912

RESUMO

Fluoride ions are used in battery electrolytes in fluoride shuttle batteries. Since organic solvents are used in battery electrolytes, there is a growing demand to develop appropriate methods for quantifying fluoride ion concentration in organic solvents. In this study, a fluoride ion-selective electrode (ISE) for organic solutions is proposed as an electrode of the second kind. A Ag|AgF electrode was made via the anodization of a silver wire in propylene carbonate (PC) containing dissolved fluoride ions. The resultant electrode exhibits a stable linear response of the open circuit potential to the logarithm of the fluoride ion concentration in PC solutions over a range of 10-4-10-2 mol dm-3. The lower and upper limits of the linear response were interpreted in terms of the solubility and the formation of a silver fluoride complex. The use of this electrode of the second kind is suitable for the analysis of fluoride ions in organic solutions and is a promising concept for the development of ISEs for the detection of ions in organic solutions under highly restrictive conditions.

14.
ACS Appl Mater Interfaces ; 13(37): 44284-44293, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34516104

RESUMO

This study attempted to stabilize the nanosurface of LiNiO2 (LNO) electrodes by varying the electrolyte concentration, significantly influencing its initial electrochemical behaviors for use in aqueous lithium-ion batteries. The charge/discharge capacities, reversibility, and cyclability of LNO were improved during initial cycles with an increase in the concentration of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). As determined by the galvanostatic intermittent titration technique, the superior diffusivity of Li+ ions in the LNO electrode is also obtained in the concentrated electrolyte. Nanoscale observation of the LNO surface revealed that its morphology is maintained relatively well in the concentrated electrolyte while it is destroyed in dilute electrolytes after the initial electrochemical cycles. These results are considered to be attributable to the variation of the interface condition in the electrical double layer with an increase in the electrolyte concentration, thus stabilizing the nanosurface of LNO by suppressing the dissolution of Ni ions from the surface. Additionally, in situ X-ray diffraction analysis demonstrated that LNO shows more stable phase transitions and volume changes as the electrolyte concentration increases, indicating that its structural changes in bulk can be directly related to the state of the nanosurface, which has a positive impact on the initial electrochemical behaviors in this system.

15.
ACS Omega ; 6(29): 18737-18744, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34337213

RESUMO

Carbon nanosphere (CNS) electrodes are the candidate of sodium-ion battery (SIB) negative electrodes with small internal resistances due to their small particle sizes. Electrochemical properties of low-crystallized CNS electrodes in dilute and concentrated sodium bis(trifluoromethanesulfonyl) amide/ethylene carbonate + dimethyl carbonate (NaTFSA/EC + DMC) were first investigated. From the cyclic voltammograms, both lithium ion and sodium ion can reversibly insert into/from CNSs in all of the electrolytes used here. The cycling stability of CNSs in concentrated electrolytes was better than that in dilute electrolytes for the SIB system. The interfacial charge-transfer resistances at the interface between CNSs and organic electrolytes were evaluated using electrochemical impedance spectroscopy. In the Nyquist plots, the semicircles at the middle-frequency region were assigned to the parallel circuits of charge-transfer resistances and capacitances. The interfacial sodium-ion transfer resistances in concentrated organic electrolytes were much smaller than those in dilute electrolytes, and the rate capability of CNS electrodes in sodium salt-concentrated electrolytes might be better than in dilute electrolytes, suggesting that CNSs with concentrated electrolytes are the candidate of SIB negative electrode materials with high rate capability. The calculated activation energies of interfacial sodium-ion transfer were dependent on electrolyte compositions and similar to those of interfacial lithium-ion transfer.

16.
ACS Appl Mater Interfaces ; 13(30): 35625-35638, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34309361

RESUMO

Conversion/alloy active materials, such as ZnO, are one of the most promising candidates to replace graphite anodes in lithium-ion batteries. Besides a high specific capacity (qZnO = 987 mAh g-1), ZnO offers a high lithium-ion diffusion and fast reaction kinetics, leading to a high-rate capability, which is required for the intended fast charging of battery electric vehicles. However, lithium-ion storage in ZnO is accompanied by the formation of lithium-rich solid electrolyte interphase (SEI) layers, immense volume expansion, and a large voltage hysteresis. Nonetheless, ZnO is appealing as an anode material for lithium-ion batteries and is investigated intensively. Surprisingly, the conclusions reported on the reaction mechanism are contradictory and the formation and composition of the SEI are addressed in only a few works. In this work, we investigate lithiation, delithiation, and SEI formation with ZnO in ether-based electrolytes for the first time reported in the literature. The combination of operando and ex situ experiments (cyclic voltammetry, X-ray photoelectron spectroscopy, X-ray diffraction, coupled gas chromatography and mass spectrometry, differential electrochemical mass spectrometry, and scanning electron microscopy) clarifies the misunderstanding of the reaction mechanism. We evidence that the conversion and alloy reaction take place simultaneously inside the bulk of the electrode. Furthermore, we show that a two-layered SEI is formed on the surface. The SEI is decomposed reversibly upon cycling. In the end, we address the issue of the volume expansion and associated capacity fading by incorporating ZnO into a mesoporous carbon network. This approach reduces the capacity fading and yields cells with a specific capacity of above 500 mAh g-1 after 150 cycles.

17.
ACS Appl Mater Interfaces ; 12(50): 56076-56085, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33258580

RESUMO

This study investigated the fundamental mechanisms of the loss of capacity of LiNiO2 (LNO) electrodes for Li+ insertion/deinsertion with a special focus on the origin of this deterioration in an aqueous system. In situ Raman spectra revealed that the intercalation of H+ ions formed a NiOOHx film at the surface of LNO during the initial electrochemical cycles; this NiOOHx film was also confirmed by X-ray photoelectron spectroscopy and transmission electron microscopy analysis. The formation of an electrochemically inactive spinel-like phase (Ni3O4) at the subsurface was triggered by the absence of Li in the NiOOHx film at the surface. These structural changes of LNO, accelerated by the intercalation of H+ ions, were considered to be the fundamental cause of the greater loss of capacity in the aqueous system.

18.
Sci Data ; 7(1): 395, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188206

RESUMO

Electrically rechargeable zinc oxygen batteries are promising energy storage devices. They appeal due to the abundance of zinc metal and their high energy density. Research on zinc oxygen batteries is currently focusing on the development of electrode materials. Since the progress is rapid and no state-of-the-art is agreed upon yet, it is difficult to benchmark their performance. This circumstance also complicates the use of the generated electrochemical data for model-based research - simulating the processes in the battery requires reliable performance data and material properties from experimental investigations. Herein we describe reproducible data on the cycling performance and durability of zinc oxygen batteries. We utilize anodes and gas diffusion electrodes (with the bifunctional catalysts Sr2CoO3Cl, Ru-Sn oxide, and Fe0.1Ni0.9Co2O4 with activated carbon) with low degradation during cycling, and present voltage data of current-dependent discharge and charge. All in all, we stimulate to reuse the data for parameter fitting in model-based work, and also to evaluate novel battery materials by preventing or minimizing side reactions with the testing protocol and setup utilized.

19.
J Clin Endocrinol Metab ; 105(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877504

RESUMO

PURPOSE: To identify the upstream regulators (URs) involved in the onset and pathogenesis of ovarian endometrioma. METHODS: Recently, a method called Significance-based Modules Integrating the Transcriptome and Epigenome (SMITE) that uses transcriptome data in combination with publicly available data for identifying URs of cellular processes has been developed. Here, we used SMITE with transcriptome data from ovarian endometrioma stromal cells (ovESCs) and eutopic endometrium stromal cells (euESCs) in combination with publicly available gene regulatory network data. To confirm the URs identified by SMITE, we developed a Boolean network simulation to see if correcting aberrant expressions of the identified genes could restore the entire gene expression profile of ovESCs to a profile similar to that of euESCs. We then established euESCs overexpressing the identified gene and characterized them by cell function assays and transcriptome analysis. RESULTS: SMITE identified 12 potential URs in ovarian endometrioma that were confirmed by the Boolean simulation. One of the URs, HOXC8, was confirmed to be overexpressed in ovESCs. HOXC8 overexpression significantly enhanced cell proliferation, migration, adhesion, and fibrotic activities, and altered expression statuses of the genes involved in transforming growth factor (TGF)-ß signaling. HOXC8 overexpression also increased the expression levels of phosphorylated SMAD2/SMAD3. The increased adhesion and fibrosis activities by HOXC8 were significantly inhibited by E-616452, a selective inhibitor of TGF-ß receptor type I kinases. MAIN CONCLUSIONS: Integrated genomic approaches identified HOXC8 as an UR in ovarian endometrioma. The pathological features of ovarian endometrioma including cell proliferation, adhesion, and fibrosis were induced by HOXC8 and its subsequent activation of TGF-ß signaling.


Assuntos
Endometriose/genética , Proteínas de Homeodomínio/fisiologia , Doenças Ovarianas/genética , Adulto , Movimento Celular/genética , Células Cultivadas , Endometriose/patologia , Epigenoma , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genômica/métodos , Proteínas de Homeodomínio/genética , Humanos , Pessoa de Meia-Idade , Doenças Ovarianas/patologia , Integração de Sistemas , Transcriptoma
20.
ChemSusChem ; 13(16): 3944, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32720759

RESUMO

Invited for this month's cover are the groups of Shih-kang Lin at the National Cheng Kung University and Takeshi Abe at Kyoto University. The image shows how interfacial chemistry design can play a role in unlocking higher-energy-density and fast-charging Li4 Ti5 O12 -based lithium-ion batteries for electric vehicle applications. The Full Paper itself is available at 10.1002/cssc.202001086.

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