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1.
J Am Chem Soc ; 146(13): 8928-8938, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526298

RESUMO

Understanding the effect of noncovalent interactions of intermediates at the polarized catalyst-electrolyte interface on water oxidation kinetics is key for designing more active and stable electrocatalysts. Here, we combine operando optical spectroscopy, X-ray absorption spectroscopy (XAS), and surface-enhanced infrared absorption spectroscopy (SEIRAS) to probe the effect of noncovalent interactions on the oxygen evolution reaction (OER) activity of IrOx in acidic and alkaline electrolytes. Our results suggest that the active species for the OER (Ir4.x+-*O) binds much stronger in alkaline compared with acid at low coverage, while the repulsive interactions between these species are higher in alkaline electrolytes. These differences are attributed to the larger fraction of water within the cation hydration shell at the interface in alkaline electrolytes compared to acidic electrolytes, which can stabilize oxygenated intermediates and facilitate long-range interactions between them. Quantitative analysis of the state energetics shows that although the *O intermediates bind more strongly than optimal in alkaline electrolytes, the larger repulsive interaction between them results in a significant weakening of *O binding with increasing coverage, leading to similar energetics of active states in acid and alkaline at OER-relevant potentials. By directly probing the electrochemical interface with complementary spectroscopic techniques, our work goes beyond conventional computational descriptors of the OER activity to explain the experimentally observed OER kinetics of IrOx in acidic and alkaline electrolytes.

2.
Faraday Discuss ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016534

RESUMO

Lithium (Li) metal negative electrodes have attracted wide attention for high-energy-density batteries. However, their low coulombic efficiency (CE) due to parasitic electrolyte reduction has been an alarming concern. Concentrated electrolytes are one of the promising concepts that can stabilize the Li metal/electrolyte interface, thus increasing the CE; however, its mechanism has remained controversial. In this work, we used a combination of LiN(SO2F)2 (LiFSI) and weakly solvating 1,2-diethoxyethane (DEE) as a model electrolyte to study how its liquid structure changes upon increasing salt concentration and how it is linked to the Li plating/stripping CE. Based on previous works, we focused on the Li electrode potential (ELi with reference to the redox potential of ferrocene) and solid-electrolyte-interphase (SEI) formation. Although ELi shows a different trend with DEE compared to conventional 1,2-dimethoxyethane (DME), which is accounted for by different ion-pair states of Li+ and FSI-, the ELi-CE plots overlap for both electrolytes, suggesting that ELi is one of the dominant factors of the CE. On the other hand, the extensive ion pairing results in the upward shift of the FSI- reduction potential, as demonstrated both experimentally and theoretically, which promotes the FSI--derived inorganic SEI. Both ELi and SEI contribute to increasing the Li plating/stripping CE.

3.
BMC Musculoskelet Disord ; 25(1): 139, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355529

RESUMO

BACKGROUND: Nail-patella syndrome (NPS) is a rare autosomal dominant disorder that is characterized by dysplasia of the nails, hypoplasia and/or dislocation of the patella and the presence of iliac horns. Using the CARE guidelines, we present the first reported case of NPS that was newly diagnosed at the onset of rheumatoid arthritis (RA). CASE PRESENTATION: A 74-year-old man was admitted to our hospital due to an 8-month history of arthralgia in bilateral wrists, elbows and fingers. He had a past history of glaucoma and left patella dislocation that had been operatively recentered at the age of 15 years. Laboratory data showed elevated levels of serum C-reactive protein and rheumatoid factor and an elevated titer of anti-SS-A antibodies, while estimated glomerular filtration rate (eGFR), titers of other antibodies and the results of a urinary test were normal. An X-ray showed deformity of bilateral radial heads and the right elbow, and magnetic resonance imaging (MRI) of his hands showed synovitis and erosion in the multiple swollen joints of the wrists and fingers. In addition to these typical features of RA, he had bilateral thumb nail dysplasia with mild hypoplasia of bilateral patellae and iliac horns as shown by the X-ray. He was diagnosed as having autosomal dominant disorder NPS co-existing with RA and he was treated with methotrexate in combination with an oral Janus kinase (JAK) inhibitor, leading to induction of remission. CONCLUSIONS: We have presented a rare case of NPS that was newly diagnosed at the onset of RA. Clinical and radiographic findings of NPS are highlighted in this case report for diagnosing NPS on the basis of typical manifestations.


Assuntos
Artrite Reumatoide , Síndrome da Unha-Patela , Luxação Patelar , Idoso , Humanos , Masculino , Artrite Reumatoide/complicações , Artrite Reumatoide/diagnóstico , Imageamento por Ressonância Magnética , Síndrome da Unha-Patela/diagnóstico , Síndrome da Unha-Patela/diagnóstico por imagem , Luxação Patelar/complicações , Radiografia
4.
Rheumatology (Oxford) ; 62(6): 2154-2159, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36264112

RESUMO

OBJECTIVES: Although personality characteristics of patients with SLE affect their disease activity and damage, it is unclear whether those of attending physicians affect the outcomes of patients with SLE. Grit is a personality trait for achieving long-term goals that may influence the decision-making for continuing treatment plans for patients. We aimed to evaluate the relationship between the grit of attending physicians and achievement of treatment goals in patients with SLE. METHODS: This cross-sectional study was conducted at five referral hospitals. The main exposure was 'consistency of interest' and 'perseverance of effort' of the attending physicians, measured by the Short Grit Scale. The primary outcome was achievement of a lupus low disease activity state (LLDAS). The association between physicians' grit score and LLDAS was analysed by generalized estimating equation (GEE) logistic regression with cluster robust variance estimation, with adjustment for confounders. RESULTS: The median (interquartile range) total, consistency and perseverance scores of 37 physicians were 3.1 (2.9-3.6), 3.3 (2.8-3.8) and 3.3 (3.0-3.5), respectively. Among the 386 patients, 154 (40%) had achieved LLDAS. Low consistency score (≤2.75) in physicians was related to LLDAS achievement independently using GEE logistic regression. The score of the question 'I often set a goal but later choose to pursue a different one' was significantly higher in patients achieving LLDAS. CONCLUSIONS: Difficulty of attending physicians to change treatment goals might be related to lower LLDAS achievement in patients with SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Médicos , Humanos , Objetivos , Estudos Transversais , Lúpus Eritematoso Sistêmico/terapia , Personalidade , Índice de Gravidade de Doença
5.
Lupus ; 32(4): 531-537, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36800905

RESUMO

OBJECTIVE: Fatigue is one of the most common complaints and is a potentially modifiable issue in systemic lupus erythematosus (SLE). Studies suggest that alcohol consumption has a protective effect against the development of SLE; however, an association between alcohol consumption and fatigue in patients with SLE has not been studied. Here, we assessed whether alcohol consumption was associated with fatigue using lupus patient-reported outcomes (LupusPRO). METHODS: This cross-sectional study, conducted between 2018 and 2019, included 534 patients (median age, 45 years; 87.3% female) from 10 institutions in Japan. The main exposure was alcohol consumption, which was defined as the frequency of drinking [<1 day/month (none group), ≤1 day/week (moderate group), and ≥2 days/week (frequent group)]. The outcome measure was the Pain Vitality domain score in LupusPRO. Multiple regression analysis was performed as the primary analysis after adjusting for confounding factors, such as age, sex, and damage. Subsequently, the same analysis was performed as a sensitivity analysis after multiple imputations (MIs) for missing data (n = 580). RESULTS: In total, 326 (61.0%) patients were categorized into the none group, 121 (22.7%) into the moderate group, and 87 (16.3%) into the frequent group. The frequent group was independently associated with less fatigue compared with none group [ß = 5.98 (95% CI 0.19-11.76), p = 0.04], and the results did not substantially deviate after MI. CONCLUSIONS: Frequent drinking was associated with less fatigue, which highlights the need for further longitudinal studies focusing on drinking habits in patients with SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Qualidade de Vida , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/epidemiologia , Fadiga/epidemiologia , Fadiga/etiologia , Sistema de Registros , Índice de Gravidade de Doença , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia
6.
J Clin Rheumatol ; 29(6): 268-274, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37226300

RESUMO

OBJECTIVES: There is a high prevalence of burnout among rheumatologists. Grit, which is defined as possessing perseverance and a passion to achieve long-term goals, is predictive of success in many professions; however, whether grit is associated with burnout remains unclear, especially among academic rheumatologists, who have multiple simultaneous responsibilities. Thus, the purpose of this study was to examine the associations between grit and self-reported burnout components-professional efficacy, exhaustion, and cynicism-in academic rheumatologists. METHODS: This cross-sectional study involved 51 rheumatologists from 5 university hospitals. The exposure was grit, measured using mean scores for the 8-item Short Grit Scale (range, 1-5 [5 = extremely high grit]). The outcome measures were mean scores for 3 burnout domains (exhaustion, professional efficacy, and cynicism; range, 1-6; measured using the 16-item Maslach Burnout Inventory-General Survey). General linear models were fitted with covariates (age, sex, job title [assistant professor or higher vs lower], marital status, and having children). RESULTS: Overall, 51 physicians (median age, 45 years; interquartile range, 36-57; 76% men) were included. Burnout positivity was found in 68.6% of participants (n = 35/51; 95% confidence interval [CI], 54.1, 80.9). Higher grit was associated with higher professional efficacy (per 1-point increase; 0.51 point; 95% CI, 0.18, 0.84) but not with exhaustion or cynicism. Being male and having children were associated with lower exhaustion (-0.69; 95% CI, -1.28, -0.10; p = 0.02; and -0.85; 95% CI, -1.46, -0.24; p = 0.006). Lower job title (fellow or part-time lecturer) was associated with higher cynicism (0.90; 95% CI, 0.04, 1.75; p = 0.04). CONCLUSIONS: Grit is associated with higher professional efficacy among academic rheumatologists. To prevent burnout among staff, supervisors who manage academic rheumatologists should assess their staff's individual grit.


Assuntos
Esgotamento Profissional , Lúpus Eritematoso Sistêmico , Médicos , Criança , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Reumatologistas , Estudos Transversais , Esgotamento Profissional/epidemiologia , Inquéritos e Questionários
7.
Phys Chem Chem Phys ; 23(16): 10070-10080, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33871005

RESUMO

Polymeric materials are considered as promising electrolytes for all-solid-state secondary lithium batteries with superior energy and power densities, long cycle lives, and high safety. To further improve the ionic conductivity of polymer electrolytes, the development of a simple and efficient method that enables precise tuning of the three key factors, polymer segmental dynamics, Li+ coordination structure, and salt dissociability, is desired. In this study, we focus on an amidation reaction, which is a simple reaction with broad applicability, to explore the impact of the side-chain structure on the intermolecular interactions within the polymer, which dictates the aforementioned key factors. We synthesized a series of polyoxetane-based polymers having different branched side-chains, i.e., methyl (PtBuOA) and bulky cyanoethoxy (P3CEOA) groups, via amidation reaction. Spectro(electro)chemical analysis verified that the large steric hindrance of the cyanoethoxy side-chain effectively breaks the hydrogen bond network and dipole interaction within the polymer, both of which decrease the polymer segmental mobility, leading to better long-range Li+ conduction. Furthermore, the unique Li+ coordination structure consisting of a cyano group, ether/carboxyl oxygen, and TFSA anion in P3CEOA electrolytes has moderate stability, which effectively promotes the short-range Li+ conduction. The amide group, with a relatively high dielectric constant, improves the dissociability of lithium salt. We confirmed a more than three orders of magnitude improvement in ionic conductivity by introducing the cyanoethoxy side-chain, than that obtained by introducing the PtBuOA electrolyte with a methyl side-chain. This work provides a holistic picture of the effect of the side-chain structure on the intermolecular interaction and establishes the new design strategy for polymer electrolytes, which enables the precise tuning of the molecular interaction using the side-chain structure.

8.
Phys Chem Chem Phys ; 23(42): 24396-24402, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34693410

RESUMO

We present a scheme to extract the adsorption energy, adsorbate interaction parameter and the saturation coverage from temperature programmed desorption (TPD) experiments. We propose that the coverage dependent adsorption energy can be fit using a functional form including the configurational entropy and linear adsorbate-adsorbate interaction terms. As one example of this scheme, we analyze TPD of CO desorption on Au(211) and Au(310) surfaces. We determine that under atmospheric CO pressure, the steps of both facets adsorb between 0.4-0.9 ML coverage of CO*. We compare this result against energies obtained from five density functionals, RPBE, PBE, PBE-D3, RPBE-D3 and BEEF-vdW. We find that the energies and equilibrium coverages from RPBE-D3 and PBE are closest to the values determined from the TPD.

9.
Chemphyschem ; 20(22): 2899, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31737982

RESUMO

The front cover artwork is provided by the groups of Prof. Yu Katayama and Prof. Hiromori Tsutsumi at the Yamaguchi University, Japan. The image shows the unique microstructures of electrospun flexible fibers, coated with copper, designed as an efficient oxygen evolution reaction (OER) electrocatalyst. Read the full text of the Article at 10.1002/cphc.201900663.

10.
Chemphyschem ; 20(22): 2973-2980, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31433539

RESUMO

Developing oxygen evolution reaction (OER) catalysts with high activity, long-term durability, and at low cost remains a great challenge. Herein, we report the high activity of fibrous Cu-based catalysts. The synthesis process is simple and scalable. Electrospinning method was selected to synthesize fibrous polymer substrates (Poly(vinylidene fluoride-co-hexafluoropropylene, PVdF-HFP), which are then covered by Cu via electroless deposition. Cu-deposited PVdF-HFP with different microstructures having smooth and roughened surfaces were also synthesized by drop-casting and impregnation method, respectively, to emphasize the importance of the microstructures on OER activity. The OER activity and durability were studied by linear sweep voltammetry, chronoamperometry, and Tafel slope analysis. The Cu/PVdF-HFP fibrous catalysts exhibit significantly improved OER activity and durability compared with Cu plate as well as Cu-deposited PVdF-HFP with different microstructures. The unique fibrous structure provides better mass transport, diffusion, and large active surface area. In addition to the advantages of the fibrous structure, attenuated total reflection infrared (ATR-IR) and ex situ X-ray photoelectron spectroscopy revealed that the improved specific activity for Cu/PVdF-HFP fiber can be attributed to the synergistic effect between Cu and Cu/PVdF-HFP (electron transfer from Cu to PVdF-HFP) at the Cu|PVdF-HFP interface, which results in optimized reaction energetics for the OER.

11.
Phys Chem Chem Phys ; 20(23): 15680-15686, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29845989

RESUMO

Understanding and controlling non-covalent interactions associated with solvent molecules and redox-inactive ions provide new opportunities to enhance the reaction entropy changes and reaction kinetics of metal redox centers, which can increase the thermodynamic efficiency of energy conversion and storage devices. Here, we report systematic changes in the redox entropy of one-electron transfer reactions including [Fe(CN)6]3-/4-, [Fe(H2O)6]3+/2+ and [Ag(H2O)4]+/0 induced by the addition of redox inactive ions, where approximately twenty different known structure making/breaking ions were employed. The measured reaction entropy changes of these redox couples were found to increase linearly with higher concentration and greater structural entropy (having greater structure breaking tendency) for inactive ions with opposite charge to the redox centers. The trend could be attributed to the altered solvation shells of oxidized and reduced redox active species due to non-covalent interactions among redox centers, inactive ions and water molecules, which was supported by Raman spectroscopy. Not only were these non-covalent interactions shown to increase reaction entropy, but they were also found to systematically alter the redox kinetics, where increasing redox reaction energy changes associated with the presence of water structure breaking cations were correlated linearly with the greater exchange current density of [Fe(CN)6]3-/4-.

13.
Phys Chem Chem Phys ; 18(15): 10109-15, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27009749

RESUMO

The electrochemical oxidation of 2-propanol over Pt and Pd electrodes was evaluated in alkaline media. Linear sweep voltammograms (LSVs), chronoamperograms (CAs), and simultaneous time-resolved attenuated total reflection infrared (ATR-IR) spectra of both electrodes were obtained in a 0.25 M KOH solution containing 1 M 2-propanol. The onset potential of 2-propanol oxidation for Pt was lower than that for Pd in LSVs while the degree of performance degradation observed for Pd was significantly smaller than that observed for Pt in CAs. The main product of 2-propanol oxidation was acetone over both electrodes and, over Pt only, acetone produced was catalytically oxidized to the enolate ion, which was accumulated on the Pt surface, leading to significant performance degradation. Carbon dioxide and carbonate species (CO3(2-), HCO3(-)) were not observed during 2-propanol oxidation over both electrodes, indicating that the complete oxidation of 2-propanol to CO2 will be a minor reaction.

15.
Langmuir ; 31(42): 11717-23, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26447852

RESUMO

The electrochemical oxidation of ammonia over Pt electrode in alkaline aqueous solutions was studied by in situ attenuated total reflection infrared (ATR-IR) spectroscopy. In 0.1 M NH3-1 M KOH, the band ascribable to the HNH bending mode of adsorbed NH3 was confirmed at 1662-1674 cm(-1) in the potential range of 0.1-1.1 V. The intensity of this band decreased continuously with a rise in potential, indicating the oxidative consumption of adsorbed ammonia. In response to this behavior, the band at 1269 cm(-1) appeared alternatively above 0.2 V, and its intensity reached the local maximal value at ca. 0.4 V. Note that this potential of ca. 0.4 V agreed well with the onset potential of ammonia oxidation, ca. 0.45 V, in the linear sweep voltammogram. This 1269 cm(-1) band was assigned to the NH2 wagging mode of N2H4, which was one of the active intermediates, N2H(x+y,ad) (x = 1 or 2, y = 1 or 2), according to the mechanism proposed by Gerischer and Mauere. To the best of our knowledge, this is the first report for the detection of N2H4 as a reaction intermediate over Pt electrode. Furthermore, the formation of bridged NO was also observed above the onset potential of ammonia oxidation, ca. 0.5 V. Such adsorbed NO species probably inhibit the electrochemical reaction due to the occupation of reaction sites at higher potential.

17.
Mem Cognit ; 42(3): 421-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24222319

RESUMO

The present study investigated context effects of incidental odors in free recall after a short retention interval (5 min). With a short retention interval, the results are not confounded by extraneous odors or encounters with the experimental odor and possible rehearsal during a long retention interval. A short study time condition (4 s per item), predicted not to be affected by adaptation to the odor, and a long study time condition (8 s per item) were used. Additionally, we introduced a new method for recovery from adaptation, where a dissimilar odor was briefly presented at the beginning of the retention interval, and we demonstrated the effectiveness of this technique. An incidental learning paradigm was used to prevent overshadowing from confounding the results. In three experiments, undergraduates (N = 200) incidentally studied words presented one-by-one and received a free recall test. Two pairs of odors and a third odor having different semantic-differential characteristics were selected from 14 familiar odors. One of the odors was presented during encoding, and during the test, the same odor (same-context condition) or the other odor within the pair (different-context condition) was presented. Without using a recovery-from-adaptation method, a significant odor-context effect appeared in the 4-s/item condition, but not in the 8-s/item condition. Using the recovery-from-adaptation method, context effects were found for both the 8- and the 4-s/item conditions. The size of the recovered odor-context effect did not change with study time. There were no serial position effects. Implications of the present findings are discussed.


Assuntos
Adaptação Psicológica/fisiologia , Rememoração Mental/fisiologia , Percepção Olfatória/fisiologia , Retenção Psicológica/fisiologia , Adulto , Humanos , Odorantes , Fatores de Tempo , Adulto Jovem
18.
J Colloid Interface Sci ; 668: 599-606, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38691968

RESUMO

HYPOTHESIS: The formation of soft colloidal crystals, which are nonclose-packed ordered arrays of colloidal particles suspended in a solvent, is dictated by a single physical factor that yields a fixed threshold at order-disorder boundaries for different experimental conditions such as ion concentration, solvent type, and particle size. Identifying the determinant factor and its threshold value should enable the prediction of the critical concentrations of colloidal particles to form soft colloidal crystals. EXPERIMENTS: Soft colloidal crystals were fabricated using a series of monohydric alcohols as dispersion media and reflectance spectra were measured to locate order-disorder boundaries. The interaction forces acting between particles were also measured by employing atomic force microscopy. FINDINGS: The interparticle forces at the order-disorder boundaries exhibited a universal threshold that was independent of the solvent types including alcohols and water. Therefore, the determinant factor for the formation of soft colloidal crystals was determined to be the force acting between the particles. Furthermore, a priori calculation of this critical force and consequently the critical particle concentration in colloidal systems was demonstrated by referring to the pressure at the liquid-to-solid transition in a hard sphere system (Alder transition).

19.
Intern Med ; 63(5): 671-676, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37468249

RESUMO

A 34-year-old woman with pulmonary arterial hypertension (PAH) was admitted to the hospital. She had been diagnosed with PAH three years earlier and treated with triple vasodilator therapy. She was positive for anti-U1 ribonucleoprotein antibodies but did not show any other symptoms associated with autoimmune diseases. Corticosteroid and cyclophosphamide therapy was administered, suspecting the involvement of immunological pathophysiology. After 3 weeks, the mean pulmonary artery pressure decreased from 50 to 38 mmHg without any change in the vasodilators. Immunosuppressive therapy was effective in this patient with PAH with an anti-U1 ribonucleoprotein-antibody-positive response and might be an option for patients with these specific features.


Assuntos
Hipertensão Arterial Pulmonar , Feminino , Humanos , Adulto , Hipertensão Arterial Pulmonar/tratamento farmacológico , Imunossupressores/uso terapêutico , Anticorpos Antinucleares , Corticosteroides , Ribonucleoproteínas
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