Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Am J Emerg Med ; 78: 132-139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38271790

RESUMO

INTRODUCTION: Considering the few studies evaluating bystander cardiopulmonary resuscitation (CPR) performance, we sought to analyze differences in bystander CPR performance with and without the use of our self-developed animated GIFs based on dispatcher-assisted CPR simulation. METHODS: A total of 80 adults who had not received CPR training over the past two years participated in the study. Among them, 40 people were classified into the auditory group (receiving CPR instructions only over the phone), and the other 40 people were classified into the audiovisual group (receiving CPR instructions over the phone after receiving images on a smartphone). All participants were asked to perform adult and infant CPR for 2 min. CPR performance was recorded using two video cameras (front and side) and analyzed by two emergency physicians, whereas CPR quality was measured using Resusci Anne & Baby QCPR Mk II (Laerdal). RESULTS: In the adult CPR study, the audiovisual group had higher performance scores for adequacy of "knee position," "hand posture," "elbow extension," and "vertical compression," as well as higher Standard Posture Completeness and Instruction Performance scores (p < 0.001). No significant difference in CPR quality was observed between the two groups. In the infant CPR study, audiovisual group had higher performance scores in adequacy of "compression site," "finger posture," and "vertical compression," as well as higher Standard Posture Completeness and Instruction Performance scores (p < 0.001). Regarding CPR quality, the audiovisual group had higher scores for "adequate compression rate ratio" (p = 0.047). CONCLUSION: Audiovisual guidance using animated GIFs more effectively improved CPR Standard Posture Completeness and Instruction Performance than did traditional auditory guidance.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Reanimação Cardiopulmonar/métodos , Telefone , Smartphone , Simulação por Computador , Pressão
2.
Prev Sci ; 24(3): 455-466, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-33970410

RESUMO

The Tucker-Lewis index (TLI; Tucker & Lewis, 1973), also known as the non-normed fit index (NNFI; Bentler & Bonett, 1980), is one of the numerous incremental fit indices widely used in linear mean and covariance structure modeling, particularly in exploratory factor analysis, tools popular in prevention research. It augments information provided by other indices such as the root-mean-square error of approximation (RMSEA). In this paper, we develop and examine an analogous index for categorical item level data modeled with item response theory (IRT). The proposed Tucker-Lewis index for IRT (TLIRT) is based on Maydeu-Olivares and Joe's (2005) [Formula: see text] family of limited-information overall model fit statistics. The limited-information fit statistics have significantly better Chi-square approximation and power than traditional full-information Pearson or likelihood ratio statistics under realistic situations. Building on the incremental fit assessment principle, the TLIRT compares the fit of model under consideration along a spectrum of worst to best possible model fit scenarios. We examine the performance of the new index using simulated and empirical data. Results from a simulation study suggest that the new index behaves as theoretically expected, and it can offer additional insights about model fit not available from other sources. In addition, a more stringent cutoff value is perhaps needed than Hu and Bentler's (1999) traditional cutoff criterion with continuous variables. In the empirical data analysis, we use a data set from a measurement development project in support of cigarette smoking cessation research to illustrate the usefulness of the TLIRT. We noticed that had we only utilized the RMSEA index, we could have arrived at qualitatively different conclusions about model fit, depending on the choice of test statistics, an issue to which the TLIRT is relatively more immune.


Assuntos
Análise Fatorial , Humanos , Psicometria , Reprodutibilidade dos Testes
3.
Multivariate Behav Res ; 57(2-3): 179-207, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33576257

RESUMO

Research has revealed that the performance of root mean square error of approximation (RMSEA) in assessing structural equation models with small degrees of freedom (df) is suboptimal, often resulting in the rejection of correctly specified or closely fitted models. This study investigates the performance of standardized root mean square residual (SRMR) and comparative fit index (CFI) in small df models with various levels of factor loadings, sample sizes, and model misspecifications. We find that, in comparison with RMSEA, population SRMR and CFI are less susceptible to the effects of df. In small df models, the sample SRMR and CFI could provide more useful information to differentiate models with various levels of misfit. The confidence intervals and p-values of a close fit were generally accurate for all three fit indices. We recommend researchers use caution when interpreting RMSEA for models with small df and to rely more on SRMR and CFI.

4.
Medicina (Kaunas) ; 58(3)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35334545

RESUMO

Sepsis is an emergent infectious disease and a leading cause of death despite immediate intervention. While Delta neutrophil index (DNI) and myeloperoxidase (MPO) are known as a prodiagnostic marker of sepsis, the preclinical evidence of the best marker of sepsis is unclear. For this, using a well-designed cecal ligation and puncture (CLP)-induced sepsis mouse model, we comparatively measured the level and cost-effectiveness of sepsis biomarkers such as DNI, myeloperoxidase (MPO), procalcitonin (PCT), and tumor necrosis factor-alpha (TNF-α). First, we found that the optimal time point for early detection is at 6 h, 24 h post-CLP. Strikingly, the peak level and fold change of DNI was revealed at 24 h, further showing the best fold change as compared with other biomarker levels. Given the fold change at 6, 24 h, PCT was next to DNI. Third, a cost-effectiveness survey showed that DNI was the best, with PCT next. Further, DNI level was moderate positively associated with PCT (ρ = 0.697, p = 0.012) and TNF-α (ρ = 0.599, p = 0.040). Collectively, these data indicate that DNI in CLP-induced sepsis mice is as effective as the existent inflammatory biomarkers such as MPO, PCT and TNF-α to predict the prognosis of sepsis. This might have clinically important implications that DNI is cost effective, thus quickly and rationally applying to diverse types of imminent sepsis regardless of species. This might be the first report on the validity of DNI in preclinical CLP-induced murine sepsis.


Assuntos
Neutrófilos , Sepse , Animais , Biomarcadores , Modelos Animais de Doenças , Humanos , Camundongos , Punções/efeitos adversos , Estudos Retrospectivos , Sepse/complicações , Sepse/diagnóstico
5.
J Chem Phys ; 154(6): 064703, 2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33588548

RESUMO

Refractory transition metal nitrides exhibit a plethora of polymorphic expressions and chemical stoichiometries. To afford a better understanding of how defects may play a role in the structural and thermodynamics of these nitrides, using density-functional theory calculations, we investigate the influence of point and pair defects in bulk metastable γ-MoN and its (001) surface. We report favorable formation of Schottky defect pairs of neighboring Mo and N vacancies in bulk γ-MoN and apply this as a defect-mediated energy correction term to the surface energy of γ-MoN(001) within the ab initio atomistic thermodynamics approach. We also inspect the structural distortions in both bulk and surfaces of γ-MoN by using the partial radial distribution function, g(r), of Mo-N bond lengths. Large atomic displacements are found in both cases, leading to a broad spread of Mo-N bond length values when compared to their idealized bulk values. We propose that these structural and thermodynamic analyses may provide some insight into a better understanding of metastable materials and their surfaces.

6.
Inorg Chem ; 57(10): 6057-6064, 2018 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-29707947

RESUMO

Oxides of tantalum (common examples including TaO, TaO2, and Ta2O5) are key oxide materials for modern electronic devices, such as dynamic random-access memory and field effect transistors. Of late, new forms of stable tantalum oxides have been proposed as two-dimensional nanosheet structures with a nonconventional stoichiometry of TaO3 via soft-chemical delamination of RbTaO3. However, not much is known about the elusive nanosheet-structured TaO3, unlike other closely related common trioxides of W and Mo. In this work, using first-principles density functional theory calculations, we have studied various TaO3 structures as inspired from previous theoretical and experimental studies and discuss their properties with respect to the more conventional oxide of tantalum, Ta2O5. We have calculated their thermodynamics and lattice properties and have found a new stable-layered ß-TaO3 and its exfoliated monolayer phase (ß'). By further analyzing their electronic structures, we discuss the mixed iono-covalent bonding characteristics in the TaO3 phases, challenging the conventional formal oxidation state model for metal oxides. Finally, we propose how these new TaO3 oxide materials may be potentially useful in photodevice applications.

7.
Soft Matter ; 12(12): 3013-20, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26809314

RESUMO

A drop impacting a solid surface with sufficient velocity will splash and emit many small droplets. However, lowering the ambient air pressure suppresses splashing completely. This effect, robustly found for different liquid and substrate properties, raises the fundamental question of how air affects a spreading drop. In a combined experimental and numerical study we characterize the flow of air induced by the drop after it hits the substrate, using a modified Schlieren optics technique combined with high-speed video imaging and Lattice-Boltzmann simulations. Our experiments reveal the emergence of air structures on different length scales. On large scales, the airflow induced in the drop's wake leads to vortex structures due to interaction with the substrate. On smaller scales, we visualize a ring structure above the outer edge of the spreading liquid generated by the spreading of the drop. Our simulations reveal the interaction between the wake vorticity and the flows originating from the rapidly escaping air from below the impacting drop. We show that the vorticity is governed by a balance between inertial and viscous forces in the air, and is unrelated to the splashing threshold.

8.
Phys Chem Chem Phys ; 18(10): 7349-58, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26899930

RESUMO

Growing ultrathin oxide layers on metal surfaces presents a new class of low-dimensional nanomaterials with exceptional chemical and physical properties. These "new oxides" can be used in many niche technologies and applications such as nanoscale electronics and heterogeneous nanocatalysis. In this work, we study the formation of surface oxidic structures and motifs of Cu, supported on the Au(111) substrate, using first-principles density-functional theory calculations in conjunction with an ab initio atomistic thermodynamics model. In particular, we systematically examine and analyze the detailed atomic structure and surface energetics of various oxidic motifs of Cu on Au(111), in particular, p2, p2s, p2(6q6) and the newly suggested metastable p2(6q6) + O3, in comparison to both the binary O/Cu(111) and O/Au(111) systems. Depending on the oxygen atmosphere and the type of surface defects introduced in the oxidic layer, various non-conventional, non-hexagonal surface oxidic motifs of Cu could be obtained. Our theoretical results agree with recent scanning tunneling microscopy (STM) experiments and we propose that metastable non-hexagonal surface motifs may pave a way to pursue further studies of these interesting complex surface oxidic layers on various metal supports.

9.
Chemosphere ; 361: 142570, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852636

RESUMO

Various contaminants of emerging concern (CECs) including pharmaceuticals and personal care products (PPCPs) have been known to threaten the aquatic ecosystem and human health even at low levels in surface water. Among them, the wide variety use of parabens as preservatives may pose potential threat to human because parabens may present estrogenic activity. Various advanced oxidation processes have been attempted to reduce parabens, but challenges using cold plasma (CP) are very rare. CP is worth paying attention to in reducing parabens because it has the advantage of generating radical ions, including reactive oxygen/nitrogen species and various ions. Accordingly, this study demonstrates how CP can be utilized and how CP competes with other advanced oxidation processes in energy requirements. Quantified ethyl-, propyl-, and butyl-paraben indicate that CP can effectively degrade them up to 99.1% within 3 h. Regression reveals that the kinetic coefficients of degradation can be increased to as high as 0.0328 min-1, comparable to other advanced oxidation processes. Many by-products generated from the oxidation of parabens provide evidence of the potential degradation pathway through CP treatment. In addition, we found that the electrical energy consumption per order of CP (39-95 kWh/m3/order) is superior to other advanced oxidation processes (69∼31,716 kWh/m3/order). Overall, these results suggest that CP may be a viable option to prevent adverse health-related consequences associated with parabens in receiving water.


Assuntos
Oxirredução , Parabenos , Poluentes Químicos da Água , Parabenos/química , Poluentes Químicos da Água/química , Gases em Plasma/química , Cinética , Conservantes Farmacêuticos/química
10.
Biol Pharm Bull ; 36(3): 339-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23449323

RESUMO

Several isolated compounds from the wood part of Thujopsis dolabrata were evaluated for their inhibitory effects against antigen-induced mast cell degranulation and interleukin-4 (IL-4) secretion, as well as IL-4 mRNA and protein expression in immunoglobulin E (IgE)-sensitized RBL-2H3 cells. Among the five isolated compounds, (-)-elema-1,3,11(13)-trien-12-ol (1) and thujopsene (2) exhibited the potent inhibitory activity against mast cell degranulation measured by ß-hexosaminidase release with IC values of 27.4 µM and 25.1 µM, respectively. These compounds also inhibited the release of IL-4 (IC values of 7.0, 6.7 µM, respectively), IL-4 mRNA expression (IC values of 16.5, 7.2 µM, respectively) and IL-4 protein expression (IC values of 17.0, 9.6 µM, respectively) in antigen-induced IgE-sensitized RBL-2H3 cells. These results suggested that (-)-elema-1,3,11(13)-trien-12-ol (1) and thujopsene (2) effectively inhibits mast cell degranulation as well as IL-4 production, suggesting that these compounds from Thujopsis dolabrata can be used as candidates for IgE-mediated allergic disorders.


Assuntos
Cupressus/química , Imunoglobulina E/imunologia , Interleucina-4/antagonistas & inibidores , Mastócitos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Degranulação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo , Interleucina-4/metabolismo , Mastócitos/fisiologia , Ratos , beta-N-Acetil-Hexosaminidases/metabolismo
11.
Arch Orthop Trauma Surg ; 133(7): 889-92, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23619919

RESUMO

Recent reports on atypical femoral fracture have raised concerns about the long-term use of bisphosphonate. More recent case series focus specifically on the subtrochanteric fractures. But, there is relatively rarity and unawareness of atypical fracture in upper extremity. We report forearm fracture in two women receiving long-term bisphosphonate therapy. First woman presented with pain in the forearm and both thighs and radiographs showed incomplete fractures in a proximal ulnar shaft and bilateral femoral shaft. The other woman had a fracture in the radial shaft. This report suggests atypical fractures associated long-term use of bisphosphonate could occur in bones other than femur. More study is required to identify the magnitude of clinical features of this emerging concern.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Fraturas do Fêmur/induzido quimicamente , Fixação Interna de Fraturas/métodos , Fraturas do Rádio/induzido quimicamente , Fraturas da Ulna/induzido quimicamente , Idoso , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/instrumentação , Humanos , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Fatores de Tempo , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgia
12.
Phys Rev E ; 107(2-2): 025308, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36932517

RESUMO

When a stationary bubble and a stationary droplet immersed in a liquid pool are brought into contact, they form a bubble-droplet aggregate. Its equilibrium morphology and stability largely depend on the combination of different components' surface tensions, known as the "spreading factor." In this study, we look at the interaction between a rising bubble and a stationary droplet to better understand the dynamics of coalescence and rising and morphological changes for the bubble-droplet aggregate. A systematic study is conducted on the interaction processes with various bubble sizes and spreading factors in two dimensions. The current simulation framework consists of the ternary conservative phase-field lattice Boltzmann method (LBM) for interface tracking and the velocity-pressure LBM for hydrodynamics, which is validated by benchmark cases such as the liquid lens and parasitic currents around a static droplet with several popular surface tension formulations. We further test our LBM for the morphology changes of two droplets initially in contact with various spreading factors and depict the final morphologies in a phase diagram. The separated, partially engulfed, and completely engulfed morphologies can be replicated by systematically altering the sign of the spreading factors. The rising bubble and stationary droplet interaction are simulated based on the final morphologies obtained under stationary conditions by imposing an imaginary buoyancy force on the rising bubble. The results indicate that the bubble-droplet aggregate with double emulsion morphology can minimize the distortion of the bubble-droplet aggregate and achieve a greater terminal velocity than the aggregate with partially engulfed morphology.

13.
Biomedicines ; 11(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38137411

RESUMO

BACKGROUND: The delta neutrophil index (DNI), a prognostic and diagnostic marker for sepsis, is based on the leukocyte count. Platelet activation, similar to leukocyte activation, plays a crucial role in host defense against pathogens and may serve as a predictor of sepsis outcome. However, the combined evaluation of mean platelet component (MPC) and DNI has rarely been used to assess sepsis. METHODS: To assess the prognostic and diagnostic validity of the simultaneous evaluation of DNI and MPC in cases of human febrile sepsis, we conducted measurements of cellular indices, including DNI and MPC, as well as molecular biomarkers, including procalcitonin (PCT) and C-reactive protein (CRP). This study was carried out in patients admitted to the emergency department with suspected sepsis. RESULTS: Using a cutoff value of 2.65%, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the DNI in sepsis were found to be 69%, 73.9%, 77.9%, and 64.1%, respectively. Furthermore, significant differences in DNI and MPC levels were observed between the sepsis and non-sepsis groups (6.7 ± 7.8% versus 2.1 ± 2.2% (p = 0.000) and 26.0 ± 1.9 g/dL versus 26.8 ± 1.4 g/dL (p = 0.002), respectively). Notably, there was a negative correlation between DNI and MPC, with the strength of the correlation varying based on the cause of sepsis. By setting the cutoff value of the DNI to 6.2%, its sensitivity, specificity, and NPV improved to 100%, 80.3%, and 100%, respectively, although the PPV remained at 10.6%. CONCLUSIONS: In our study, the DNI demonstrates superior effectiveness compared with other molecular biomarkers, such as CRP and procalcitonin, in distinguishing septic febrile patients from non-septic febrile patients. Additionally, a negative correlation exists between MPC and DNI, making MPC a valuable marker for differentiating the etiology of sepsis. These findings hold significant clinical implications, as DNI/MPC evaluation is a cost-effective and readily applicable approach in various impending sepsis scenarios. Notably, this study represents the first examination of the prognostic and diagnostic validity of employing the simultaneous evaluation of DNI and MPC in human cases of febrile sepsis.

14.
Nanomaterials (Basel) ; 13(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37686969

RESUMO

Herein, sol-gel-processed Y2O3-Al2O3 mixed oxide-based resistive random-access-memory (RRAM) devices with different proportions of the involved Y2O3 and Al2O3 precursors were fabricated on indium tin oxide/glass substrates. The corresponding structural, chemical, and electrical properties were investigated. The fabricated devices exhibited conventional bipolar RRAM characteristics without requiring a high-voltage forming process. With an increase in the percentage of Al2O3 precursor above 50 mol%, the crystallinity reduced, with the amorphous phase increasing owing to internal stress. Moreover, with increasing Al2O3 percentage, the lattice oxygen percentage increased and the oxygen vacancy percentage decreased. A 50% Y2O3-50% Al2O3 mixed oxide-based RRAM device exhibited the maximum high-resistance-state/low-resistance-state (HRS/LRS) ratio, as required for a large readout margin and array size. Additionally, this device demonstrated good endurance characteristics, maintaining stability for approximately 100 cycles with a high HRS/LRS ratio (>104). The HRS and LRS resistances were also retained up to 104 s without considerable degradation.

15.
Nanomaterials (Basel) ; 13(17)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37686940

RESUMO

Yttrium oxide (Y2O3) resistive random-access memory (RRAM) devices were fabricated using the sol-gel process on indium tin oxide/glass substrates. These devices exhibited conventional bipolar RRAM characteristics without requiring a high-voltage forming process. The effect of current compliance on the Y2O3 RRAM devices was investigated, and the results revealed that the resistance values gradually decreased with increasing set current compliance values. By regulating these values, the formation of pure Ag conductive filament could be restricted. The dominant oxygen ion diffusion and migration within Y2O3 leads to the formation of oxygen vacancies and Ag metal-mixed conductive filaments between the two electrodes. The filament composition changes from pure Ag metal to Ag metal mixed with oxygen vacancies, which is crucial for realizing multilevel cell (MLC) switching. Consequently, intermediate resistance values were obtained, which were suitable for MLC switching. The fabricated Y2O3 RRAM devices could function as a MLC with a capacity of two bits in one cell, utilizing three low-resistance states and one common high-resistance state. The potential of the Y2O3 RRAM devices for neural networks was further explored through numerical simulations. Hardware neural networks based on the Y2O3 RRAM devices demonstrated effective digit image classification with a high accuracy rate of approximately 88%, comparable to the ideal software-based classification (~92%). This indicates that the proposed RRAM can be utilized as a memory component in practical neuromorphic systems.

16.
J Clin Med ; 12(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834896

RESUMO

(1) Background: The government of South Korea has established a nationwide web- and mobile-based emergency teleconsultation network by designating urban and rural hospitals. The purpose of this study is to analyze the characteristics and effectiveness of the tele-emergency system in South Korea. (2) Methods: Tele-emergency consultation cases from May 2015 to December 2018 were analyzed in the present study. The definition of a tele-emergency in the present study is an emergency consultation between doctors in rural and urban hospitals via a web- and mobile-based remote emergency consultation system (RECS). Consultations through an RECS are grouped into three categories: medical procedure or treatment guidance, image interpretation, and transportation requests. The present study analyzed the characteristics of the tele-emergency system and the reduction in unnecessary transportation (RUT). (3) Results: A total of 2604 cases were analyzed in the present study from 2985 tele-emergency consultation cases. A total of 381 cases were excluded for missing data. Consultations for image interpretation were the most common in trauma cases (71.3%), while transfer requests were the most common in non-trauma cases (50.3%). Trauma patients were more frequently admitted to rural hospitals or discharged and followed up with at rural hospitals (20.3% vs. 40.5%) after consultations. In terms of disease severity, non-severe cases were statistically higher in trauma cases (80.6% vs. 59.4%; p < 0.001). The RUT was statistically highly associated with trauma cases (60.8% vs. 42.8%; p < 0.001). In an analysis that categorized cases by region, a statistically higher proportion of transportation was used in island regions (69.9% vs. 49.5%; p < 0.003). More RUT was associated with non-island regions (30.1% vs. 50.5%; p = 0.001). (4) Conclusions: The tele-emergency system had a great role in reducing unnecessary patient transportation in non-severe trauma cases and non-island rural area emergency cases. Further research is needed for a cost/benefit analysis and clinical outcomes.

17.
Phys Chem Chem Phys ; 14(48): 16552-7, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-22772941

RESUMO

As a first step towards a microscopic understanding of single-Pt atom-dispersed catalysts on non-conventional TiN supports, we present density-functional theory (DFT) calculations to investigate the adsorption properties of Pt atoms on the pristine TiN(100) surface, as well as the dominant influence of surface defects on the thermodynamic stability of platinized TiN. Optimized atomic geometries, energetics, and analysis of the electronic structure of the Pt/TiN system are reported for various surface coverages of Pt. We find that atomic Pt does not bind preferably to the clean TiN surface, but under typical PEM fuel cell operating conditions, i.e. strongly oxidizing conditions, TiN surface vacancies play a crucial role in anchoring the Pt atom for its catalytic function. Whilst considering the energetic stability of the Pt/TiN structures under varying N conditions, embedding Pt at the surface N-vacancy site is found to be the most favorable under N-lean conditions. Thus, the system of embedding Pt at the surface N-vacancy sites on TiN(100) surfaces could be promising catalysts for PEM fuel cells.

18.
Phys Rev E ; 106(3-1): 034310, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36266875

RESUMO

We propose a new centrality incorporating two classical node-level centralities, the degree centrality and the information centrality, which are considered as local and global centralities, respectively. These two centralities have expressions in terms of the graph Laplacian L, which motivates us to exploit its fractional analog L^{γ} with a fractional parameter γ. As γ varies from 0 to 1, the proposed fractional version of the information centrality makes intriguing changes in the node centrality rankings. These changes could not be generated by the fractional degree centrality since it is mostly influenced by the local aspect. We prove that these two fractional centralities behave similarly when γ is close to 0. This result provides its complete understanding of the boundary of the interval in which γ lies since the fractional information centrality with γ=1 is the usual information centrality. Moreover, our computation for the correlation coefficients between the fractional information centrality and the degree centrality reveals that the fractional information centrality is transformed from a local centrality into being a global one as γ changes from 0 to 1.

19.
Ear Nose Throat J ; : 1455613221098787, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35487204

RESUMO

Laryngopharyngeal or cervical pain following ingestion of foreign bodies is one of the most frequently encountered emergencies in otolaryngologic practice. Although most of these foreign bodies can be easily removed under laryngoscopic examination without any complications, surgical removal may be required when foreign bodies migrate extraluminally. This report describes two rare cases of ingested fishbones that had migrated, one each to the thyroid gland and submandibular gland. Extraluminal migration fishbones should always be considered in otolaryngologic clinics.

20.
Materials (Basel) ; 15(19)2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36234198

RESUMO

In this study, we fabricated sol-gel-processed Y2O3-based resistive random-access memory (RRAM) devices. The fabricated Y2O3 RRAM devices exhibited conventional bipolar RRAM device characteristics and did not require the forming process. The long-term stability of the RRAM devices was investigated. The Y2O3 RRAM devices with a 20 nm thick Ag top electrode showed an increase in the low resistance state (LRS) and high resistance state (HRS) and a decrease in the HRS/LRS ratio after 30 days owing to oxidation and corrosion of the Ag electrodes. However, Y2O3 RRAM devices with inert Au-passivated Ag electrodes showed a constant RRAM device performance after 30 days. The 150 nm-thick Au passivation layer successfully suppressed the oxidation and corrosion of the Ag electrode by minimizing the chance of contact between water or oxygen molecules and Ag electrodes. The Au/Ag/Y2O3/ITO RRAM devices exhibited more than 300 switching cycles with a decent resistive window (>103). They maintained constant LRS and HRS resistances for up to 104 s, without significant degradation of nonvolatile memory properties for 30 days while stored in air.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA