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1.
PLoS One ; 19(2): e0297701, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38354135

RESUMO

INTRODUCTION: ChatGPT, a sophisticated large language model (LLM), has garnered widespread attention for its ability to mimic human-like communication. As recent studies indicate a potential supportive role of ChatGPT in academic writing, we assessed the LLM's capacity to generate accurate and comprehensive scientific abstracts from published Randomised Controlled Trial (RCT) data, focusing on the adherence to the Consolidated Standards of Reporting Trials for Abstracts (CONSORT-A) statement, in comparison to the original authors' abstracts. METHODOLOGY: RCTs, identified in a PubMed/MEDLINE search post-September 2021 across various medical disciplines, were subjected to abstract generation via ChatGPT versions 3.5 and 4, following the guidelines of the respective journals. The overall quality score (OQS) of each abstract was determined by the total number of adequately reported components from the 18-item CONSORT-A checklist. Additional outcome measures included percent adherence to each CONOSORT-A item, readability, hallucination rate, and regression analysis of reporting quality determinants. RESULTS: Original abstracts achieved a mean OQS of 11.89 (95% CI: 11.23-12.54), outperforming GPT 3.5 (7.89; 95% CI: 7.32-8.46) and GPT 4 (5.18; 95% CI: 4.64-5.71). Compared to GPT 3.5 and 4 outputs, original abstracts were more adherent with 10 and 14 CONSORT-A items, respectively. In blind assessments, GPT 3.5-generated abstracts were deemed most readable in 62.22% of cases which was significantly greater than the original (31.11%; P = 0.003) and GPT 4-generated (6.67%; P<0.001) abstracts. Moreover, ChatGPT 3.5 exhibited a hallucination rate of 0.03 items per abstract compared to 1.13 by GPT 4. No determinants for improved reporting quality were identified for GPT-generated abstracts. CONCLUSIONS: While ChatGPT could generate more readable abstracts, their overall quality was inferior to the original abstracts. Yet, its proficiency to concisely relay key information with minimal error holds promise for medical research and warrants further investigations to fully ascertain the LLM's applicability in this domain.


Assuntos
Publicações Periódicas como Assunto , Humanos , Redação , Padrões de Referência , Publicações , Alucinações
2.
ACS Nano ; 17(15): 14930-14942, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37505191

RESUMO

The development of aqueous zinc-ion batteries (AZIBs) faces significant challenges because of water-induced side reactions arising from the high water activity in aqueous electrolytes. Herein, a quasi-solid-state electrolyte membrane with low water activity is designed based on a laponite (LP) nanoclay for separator-free AZIBs. The mechanically robust LP-based membrane can perform simultaneously as a separator and a quasi-solid-state electrolyte to inhibit dendrite growth and water-induced side reactions at the Zn/electrolyte interface. A combination of density functional theory calculations, theoretical analyses, and experiments ascertains that the water activities associated with self-dissociation, byproduct formation, and electrochemical decomposition could be substantially suppressed when the water molecules are absorbed by LP. This could be attributed to the high water adsorption and hydration capabilities of LP nanocrystals, resulting from the strong Coulombic and hydrogen-binding interactions between water and LP. Most importantly, the separator-free AZIBs exhibit high capacity retention rates of 94.10% after 2,000 cycles at 1 A/g and 86.32% after 10,000 cycles at 3 A/g, along with enhanced durability and record-low voltage decay rates over a 60-day storage period. This work provides a fundamental understanding of water activity and demonstrates that LP nanoclay is promising for ultrastable separator-free AZIBs for practical energy storage applications.

3.
Med Phys ; 50(6): 3435-3444, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36748167

RESUMO

BACKGROUND: Scatter radiation is a traditional problem in cone-beam computed tomography (CBCT). Accordingly, numerous methods have been researched for scatter reduction in terms of software- or hardware-based solutions. The concept of a two-dimensional antiscatter grid (2D-ASG) has been shown to provide a solution to the scatter reduction in CBCT. However, the use of an ASG makes it challenging to use in clinical CBCT systems because it causes Moire artifacts of the image. PURPOSE: We have developed a Moire-free 2D-ASG that was designed to solve the Moire artifact and the scatter radiation problems. We provide the experimental results pertaining to the image quality measurements from the evaluation of the 2D-ASG compared with those obtained from a one-dimensional antiscatter grid (1D-ASG) and no antiscatter grid (No-ASG) to demonstrate the quantitative extent of the improvements. METHODS: The 2D-ASG, fabricated based on a sawing process with a graphite body, was prepared to evaluate image quality improvements. Projection images for Pro-CT MK II phantom were acquired using the CBCT testbed of sample rotation type and reconstructed by Feldkamp-Davis-Kress (FDK) algorithm without any filters. We measured the contrast-to-noise ratio (CNR) and uniformity index for the cupping artifacts of the 2D-ASG, 1D-ASG, and No-ASG cases. RESULTS: 2D-ASG considerably reduced the cupping artifacts owing to the scatter reduction compared with the 1D-ASG and No-ASG cases. The cupping artifacts were reduced by 85% in the 2D-ASG compared with No-ASG, while the cupping artifacts were reduced by 63% in 1D-ASG compared with No-ASG. The 2D-ASG also yielded a CNR improvement. The average CNR improvements for eight insert materials were 47% in the 2D-ASG compared with No-ASG, while the CNR was improved by 36% in the 1D-ASG compared with No-ASG. CONCLUSIONS: We demonstrated that the Moire-free 2D-ASG improved the image quality by removing scatter radiation in CBCT compared with 1D-ASG and No-ASG. We believe that the Moire-free 2D-ASG can become one of the effective ways to solve the scatter radiation problem in CBCT images because it provides usability and has the potential to have synergistic effects on other methods, such as bow-tie filter and scatter correction.


Assuntos
Algoritmos , Software , Tomografia Computadorizada de Feixe Cônico/métodos , Espalhamento de Radiação , Imagens de Fantasmas , Artefatos , Processamento de Imagem Assistida por Computador/métodos
4.
Am J Physiol Heart Circ Physiol ; 322(2): H129-H144, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34890279

RESUMO

Obesity is associated with higher risks of cardiac arrhythmias. Although this may be partly explained by concurrent cardiometabolic ill-health, growing evidence suggests that increasing adiposity independently confers risk for arrhythmias. Among fat depots, epicardial adipose tissue (EAT) exhibits a proinflammatory secretome and, given the lack of fascial separation, has been implicated as a transducer of inflammation to the underlying myocardium. The present review explores the mechanisms underpinning adverse electrophysiological remodeling as a consequence of EAT accumulation and the consequent inflammation. We first describe the physiological and pathophysiological function of EAT and its unique secretome and subsequently discuss the evidence for ionic channel and connexin expression modulation as well as fibrotic remodeling induced by cytokines and free fatty acids that are secreted by EAT. Finally, we highlight how weight reduction and regression of EAT volume may cause reverse remodeling to ameliorate arrhythmic risk.


Assuntos
Tecido Adiposo/metabolismo , Arritmias Cardíacas/metabolismo , Pericárdio/metabolismo , Tecido Adiposo/patologia , Animais , Arritmias Cardíacas/patologia , Citocinas/metabolismo , Humanos , Canais Iônicos/metabolismo , Pericárdio/patologia
5.
ACS Omega ; 6(14): 9492-9499, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33869929

RESUMO

Graphite is currently utilized as anode materials for Li-ion batteries, but it is well-known that graphite does not show good electrochemical performances as the anode material for sodium-ion batteries (SIBs). It was also reported that the low electrochemical performances of graphite originated from the larger ionic radius of the sodium ion due to the required higher strain energy for sodium-ion intercalation into graphite leading to an unstable sodium-ion intercalated graphite intercalation compound (GIC). In this work, using first-principles calculations, we introduce pillaring effects of Na n X (n = 3 and 4; X = F, Cl, or Br) halide clusters in GICs, which become electrochemically active for Na redox reactions. Specifically, to enable sodium-ion intercalation into graphite, the interlayer spacing of graphite is required to increase over 3.9 Å, and Na n X halide cluster GICs maintain an expanded interlayer spacing of >3.9 Å. This enlarged interlayer spacing of Na n X halide cluster GICs facilitates stable intercalation of sodium ions. Na3F, Na4Cl, and Na4Br halide clusters are identified as suitable pillar candidates for anode materials because they not only expand the interlayer spacing but also provide reasonable binding energy for intercalated sodium ions for reversible deintercalation. Based on the model analysis, theoretical capacities of Na3F, Na4Cl, and Na4Br halide cluster GICs are estimated respectively to be 186, 155, and 155 mA h g-1. These predictions would provide a rational strategy guiding the search for promising anode materials for SIBs.

6.
Phys Chem Chem Phys ; 23(9): 5438-5446, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33646232

RESUMO

In this study, we present improved power characteristics and suppressed phase transition by incorporating elemental doping into a P2-type cathode of sodium ion batteries. A Cu-doped Fe-Mn based P2-type Na0.67Cu0.125Fe0.375Mn0.5O2 cathode was designed based on the calculations of the electronic structure and then examined experimentally. Using first principles, we introduced instrinsic p-type conductivity by elemental doping with Cu. Introduction of Cu generated electron holes above the Fermi level in the electronic structure, which is typical of p-type semiconductors. Charge analyses suggested that the hole generation was driven primarily by the greater reduced characteristics of Cu as compared with those of Fe and Mn. In addition, introduction of Cu retaining high reduced property also suppressed phase transition from the P2 to Z phase by Fe migration to empty Na layers mainly. Electrochemical experiments revealed improved power characteristics upon the introduction of p-type conductivity. This could be attributed to the increase in the electronic conductivity by hole generation in the valence band. This study suggests that the introduction of p-type conductivity could be a rational tactic for the development of promising cathode materials for high performance sodium ion batteries.

7.
ACS Appl Mater Interfaces ; 11(34): 30894-30901, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31389688

RESUMO

Recently, the substitution of inactive elements has been reported as a promising strategy for improving the structural stability and electrochemical performance of layered cathode materials for sodium-ion batteries (SIBs). In this regard, we investigated the positive effects of inactive Ti substitution into O3-type NaFe0.25Ni0.25Mn0.5O2 based on first-principles calculations and electrochemical experiments. After Ti substitution, Na[Ti0.03(Fe0.25Ni0.25Mn0.5)0.97]O2 exhibits improved capacity retention and rate capability compared with Ti-free NaFe0.25Ni0.25Mn0.5O2. Such an improvement is primarily attributed to the enhanced structural stability and lowered activation energy for Na+ migration, which is induced by Ti substitution in the host structure. Based on first-principles calculations of the average net charges and partial densities of states, we suggest that Ti substitution effectively enhances the binding between transition metals and oxygen by increasing the oxygen electron density, which in turn lowers the energy barrier of Na+ migration, leading to a notable enhancement in the rate capability of Na[Ti0.03(Fe0.25Ni0.25Mn0.5)0.97]O2. Compared with other inactive elements (e.g., Al and Mg), Ti is a more suitable substituent for improving the electrochemical properties of layered cathode materials because of its large total charge variation contributing to capacity. The results of this study provide practical guidelines for developing highly reliable layered cathode materials for SIBs.

8.
Phys Chem Chem Phys ; 19(16): 10443-10452, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28379270

RESUMO

A fundamental understanding of anomalous redox mechanisms in hexacyanometallate compounds, compared with conventional NaMO2 systems (M: transition metals), is presented based on first-principles calculations and experimental validations. From theoretical calculations, we identified low-spin and high-spin states of Fe ions coordinated by the cyanide group (-CN) with the same oxidation state (Fe2+) in Na2Fe2(CN)6. Considering the site dependency of d electronic spin configurations based on the crystal field theory (CFT) of transition metals (TMs), we calculated the thermodynamic mixing energy using Na2Fe2(CN)6 and Na2Mn2(CN)6 for obtaining a thermodynamically stable phase of Na2FeMn(CN)6. The phase stabilities of Na2Fe2-xMnx(CN)6 among many atomic configurations and lattice parameters originating from octahedral structures (i.e., Fe(CN)6 and Mn(NC)6) are highly dependent on the electronic structures of TMs with spin states. From partial density of states (PDOS) and spatial electron distributions, it was observed that Fe2+ in the low-spin state (t) and Mn2+ in the high-spin states (t and e) in the stable phase lead to higher redox potentials (∼3.55 V vs. Na/Na+) with the removal of Na+ as compared to that of Na2Fe2(CN)6. In addition, lattice parameters from x = 0 to x = 1 in Na2Fe2-xMnx(CN)6 are increased due to the larger ionic radius of Mn2+ in the high-spin states. On the other hand, Fe2+ in the high-spin states (t and e) and Mn2+ in the low-spin state (t) in the most unstable phase of Na2FeMn(CN)6 would have lower redox potentials. Based on the fundamental correlation between redox potentials and CFT with spin configurations of TMs, we suggest a material design concept for intercalation compounds with higher energy densities for rechargeable battery systems.

9.
Sci Rep ; 7: 39669, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-28045118

RESUMO

Ni-rich LiNi0.8Co0.1Mn0.1O2 layered oxide cathodes have been highlighted for large-scale energy applications due to their high energy density. Although its specific capacity is enhanced at higher voltages as Ni ratio increases, its structural degradation due to phase transformations and lattice distortions during cycling becomes severe. For these reasons, we focused on the origins of crack generation from phase transformations and structural distortions in Ni-rich LiNi0.8Co0.1Mn0.1O2 using multiscale approaches, from first-principles to meso-scale phase-field model. Atomic-scale structure analysis demonstrated that opposite changes in the lattice parameters are observed until the inverse Li content x = 0.75; then, structure collapses due to complete extraction of Li from between transition metal layers. Combined-phase investigations represent the highest phase barrier and steepest chemical potential after x = 0.75, leading to phase transformations to highly Li-deficient phases with an inactive character. Abrupt phase transformations with heterogeneous structural collapse after x = 0.81 (~220 mAh g-1) were identified in the nanodomain. Further, meso-scale strain distributions show around 5% of anisotropic contraction with lower critical energy release rates, which cause not only micro-crack generations of secondary particles on the interfaces between the contracted primary particles, but also mechanical instability of primary particles from heterogeneous strain changes.

10.
Sci Rep ; 5: 16544, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26559611

RESUMO

A pre-strained polystyrene (PS) polymer sheet is deformed when it approaches the glass transition state as a result of light absorption. By controlling the light absorption of the polymer sheet, non-contact sequential folding can be accomplished. Line patterns of different transparencies and shapes are used to control the light absorption. The line pattern shape is closely related to the folding angle and folding start time. The relation between the line pattern design and folding performance was evaluated experimentally to develop a technique for folding PS sheets. The results show that sequential folding of PS sheets can be accomplished by changing the degree of transparency of the line pattern. Using the technique developed in this study, self-folding origami structures with complicated shapes can be designed and manufactured.

11.
J Magn Reson ; 166(1): 35-8, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14675817

RESUMO

A programmable quantum computer is experimentally demonstrated by nuclear magnetic resonance using one qubit for the program and two qubits for data. A non-separable two-qubit operation is performed in a programmable way to show the successful demonstration. Projective measurements required in the programmable quantum computer are simulated by averaging the results of experiments just like when producing an effective pure state.


Assuntos
Computadores Moleculares , Armazenamento e Recuperação da Informação/métodos , Espectroscopia de Ressonância Magnética/instrumentação , Espectroscopia de Ressonância Magnética/métodos , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Teoria Quântica , Computadores , Metodologias Computacionais , Cristalização/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Modelos Teóricos , Marcadores de Spin
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