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1.
Mater Horiz ; 11(2): 566-577, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-37987204

RESUMO

In principle, hybrid energy storages can utilize the advantages of capacitor-type cathodes and battery-type anodes, but their cathode and anode materials still cannot realize a high energy density, fast rechargeable capability, and long-cycle stability. Herein, we report a strategy to synthesize cathode and anode materials as a solution to overcome this challenge. Firstly, 3D nitrogen-doped hierarchical porous graphitic carbon (NHPGC) frameworks were synthesized as cathode materials using Co-Zn mixed metal-organic frameworks (MOFs). A high capacity is achieved due to the abundant nitrogen and micropores produced by the MOF nanocages and evaporation of Zn. Also, fast ion/electron transport channels were derived through the Co-catalyzed hierarchical porosity control and graphitization. Moreover, tin oxide precursors were introduced in NHPGC to form the SnO2@NHPGC anode. Operando X-ray diffraction revealed that the rescaled subnanoparticles as anodic units facilitated the high capacity during ion insertion-induced rescaling. Besides, the Sn-N bonds endowed the anode with a cycling stability. Furthermore, the NHPGC cathode and SnO2@NHPGC achieved an ultrahigh energy density (up to 244.5 W h kg-1 for Li and 146.1 W h kg-1 for Na), fast rechargeable capability (up to 93C-rate for Li and 147C-rate for Na) as exhibited by photovoltaic recharge within a minute and a long-cycle stability with ∼100% coulombic efficiency over 10 000 cycles.

2.
Sci Rep ; 12(1): 10043, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710937

RESUMO

Supercapacitors are promising energy storage devices with high charging/discharging speeds and power densities. To improve their poor stability, we fabricated electrodes by integrating perovskite materials (La0.8Sr0.2Mn0.5Co0.5O3-δ, LSMCO) possessing redox reaction ability with graphene nanoplatelets exhibiting good electronic properties. One of the resultant composites (L25G70) demonstrated high capacitance and excellent capacitance retention (95% after 5000 cycles). These results are superior to other electrodes (L50G45 and L75G20) containing a larger ratio of LSMCO, even L75G20 did not exhibit supercapacitor behavior after 3000 cycles. GN can induce structural distortion in LSMCO, thereby the high amount of adsorbed oxygen per lattice oxygen can explain the best electrochemical performance of L25G70, while structural collapse rationalized the failure of L75G20. The findings of this study demonstrated that the use of LSMCO can improve the cycling stability of supercapacitors.

3.
ACS Nano ; 16(4): 6552-6564, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35377611

RESUMO

Lithium-ion batteries and pseudocapacitors are nowadays popular electrochemical energy storage for many applications, but their cathodes and anodes are still limited to accommodate rich redox ions not only for high energy density but also sluggish ion diffusivity and poor electron conductivity, hindering fast recharge. Here, we report a strategy to realize high-capacity/high-rate cathode and anode as a solution to this challenge. Multiporous conductive hollow carbon (HC) nanospheres with microporous shells for high capacity and hollow cores/mesoporous shells for rapid ion transfer are synthesized as cathode materials using quinoid:benzenoid (Q:B) unit resins of coiled conformation, leading to ∼5-fold higher capacities than benzenoid:benzenoid resins of linear conformation. Also, Ge-embedded Q:B HC nanospheres are derived as anode materials. The atomic configuration and energy storage mechanism elucidate the existence of mononuclear GeOx units giving ∼7-fold higher ion diffusivity than bulk Ge while suppressing volume changes during long ion-insertion/desertion cycles. Moreover, hybrid energy storage with a Q:B HC cathode and Ge-Q:B HC anode exploit the advantages of capacitor-type cathode and battery-type anode electrodes, as exhibited by battery-compatible high energy density (up to 285 Wh kg-1) and capacitor-compatible ultrafast rechargeable power density (up to 22 600 W kg-1), affording recharge within a minute.

4.
Nanomaterials (Basel) ; 11(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34685128

RESUMO

One of the critical issues hindering the commercialization of lithium-sulfur (Li-S) batteries is the dissolution and migration of soluble polysulfides in electrolyte, which is called the 'shuttle effect'. To address this issue, previous studies have focused on separators featuring specific chemical affinities or physical confinement by porous coating materials. However, there have been no studies on the complex effects of the simultaneous presence of the internal and interparticle spaces of porous materials in Li-S batteries. In this report, the stable Zr-based metal-organic frameworks (MOFs), UiO-66, have been used as a separator coating material to provide interparticle space via size-controlled MOF particles and thermodynamic internal space via amine functionality. The abundant interparticle space promoted mass transport, resulting in enhanced cycling performance. However, when amine functionalized UiO-66 was employed as the separator coating material, the initial specific capacity and capacity retention of Li-S batteries were superior to those materials based on the interparticle effect. Therefore, it is concluded that the thermodynamic interaction inside internal space is more important for preventing polysulfide migration than spatial condensation of the interparticle space.

6.
Adv Sci (Weinh) ; 8(11): e2100044, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34105280

RESUMO

Multimetallic electrocatalysts have shown great potential to improve electrocatalytic performance, but their deteriorations in activity and durability are yet to be overcome. Here, metal-organic fragments with adhesive excipient to realize high activity with good durability in oxygen evolution reaction (OER) are developed. First, a leaf-like zeolitic-imidazolate framework (ZIF-L) is synthesized. Then, ionized species in hydrogen plasma attack preferentially the organic linkers of ZIF-L to derive cobalt-imidazole fragments (CIFs) as adhesive excipient, while they are designed to retain the coordinated cobalt nodes. Moreover, the vacant coordination sites at cobalt nodes and the unbound nitrogen at organic linkers induce high porosity and conductivity. The CIFs serve to stably impregnate trimetallic FeNiMo electrocatalysts (CIF:FeNiMo), and CIF:FeNiMo containing Fe contents of 22% and hexavalent Mo contents show to enable high activity with low overpotentials (203 mV at 10 mA cm-2 and 238 mV at 100 mA cm-2 ) in OER. The near O K-edge extended X-ray absorption fine structure proves further that high activity for OER originates from the partially filled eg orbitals. Additionally, CIF:FeNiMo exhibit good durability, as demonstrated by high activity retention during at least 45 days in OER.

7.
World J Clin Cases ; 9(1): 267-273, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33511195

RESUMO

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a multi-system fibroin-flammatory disorder that can involve any organ, including the salivary glands, pancreas, and biliary tree. Treatment of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) is similar to that for IgG4-RD, but progression is irreversible in some cases. We present a case of IgG4-SC in which an immuno-suppressant induced marked clinical and radiologic improvement. CASE SUMMARY: A 63-year-old male presented with a prominent itching sensation and wholebody jaundice. He showed obstructive-pattern jaundice, an elevated IgG4 level, and infiltration of a large number of IgG4-positive cells in the ampulla of Vater. The imaging findings of intrahepatic duct (IHD) and common bile duct dilation, an elevated serum IgG4 level, and characteristic histological findings led to diagnosis of IgG4-SC that compatible with the 2019 ACR/EULAR classification criteria. We planned to treat the patient with high-dose glucocorticoid (GC), followed by cyclophosphamide pulse therapy. After treatment with high-dose GC and an immunosuppressant, imaging studies showed that IHD dilatation had completely resolved. CONCLUSION: Prompt diagnosis and appropriate treatment of IgG4-SC are important. Because there is a risk of relapse of IgG4-SC, the GC dose should be gradually reduced, and a maintenance immunosuppressant should be given.

9.
10.
J Int Med Res ; 48(6): 300060520931323, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32589073

RESUMO

OBJECTIVES: Celecoxib is a selective cyclooxygenase (COX)-2 inhibitor that is commonly used to reduce the incidence of gastrointestinal (GI) complications in patients with rheumatoid arthritis (RA). CELBESTA® is a generic equivalent to CELEBREX®, a celecoxib preparation. This study compared the efficacy and safety of CELBESTA® and CELEBREX® in patients with RA. METHODS: This was a multicenter, double-blind, double-dummy, active-controlled, randomized, parallel-group, non-inferiority clinical trial. The primary endpoint was a change from baseline in self-assessed pain intensity determined using a 100-mm visual analog scale after 6 weeks of treatment. RESULTS: After a washout period, 119 eligible subjects were randomized to one of two groups (CELBESTA® group, n = 61; CELEBREX® group, n = 58). CELBESTA® was not inferior to CELEBREX® because the upper limit of two-sided 95% confidence interval (CI) for the difference between the two groups (difference in the least square [LS] mean, -8.68 mm; two-sided 95% CI -16.59 mm to -0.77 mm) was less than the non-inferiority margin (10 mm). There were no significant differences in GI complications and renal toxicity. CONCLUSIONS: CELBESTA® was not inferior to CELEBREX® with regard to the pain relief efficacy in RA patients, and the tolerability and safety profiles were excellent and at similar levels for both preparations.


Assuntos
Artrite Reumatoide , Sulfonamidas , Artrite Reumatoide/tratamento farmacológico , Celecoxib/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Método Duplo-Cego , Humanos , Pirazóis/efeitos adversos , Sulfonamidas/uso terapêutico , Resultado do Tratamento
11.
Adv Sci (Weinh) ; 7(9): 2000283, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32382491

RESUMO

Sub-nanometric particles (SNPs) of atomic cluster sizes have shown great promise in many fields such as full atom-to-atom utilization, but their precise production and stabilization at high mass loadings remain a great challenge. As a solution to overcome this challenge, a strategy allowing synthesis and preservation of SNPs at high mass loadings within multishell hollow metal-organic frameworks (MOFs) is demonstrated. First, alternating water-decomposable and water-stable MOFs are stacked in succession to build multilayer MOFs. Next, using controlled hydrogen bonding affinity, isolated water molecules are selectively sieved through the hydrophobic nanocages of water-stable MOFs and transferred one by one to water-decomposable MOFs. The transmission of water molecules via controlled hydrogen bonding affinity through the water-stable MOF layers is a key step to realize SNPs from various types of alternating water-decomposable and water-stable layers. This process transforms multilayer MOFs into SNP-embedded multishell hollow MOFs. Additionally, the multishell stabilizes SNPs by π-backbonding allowing high conductivity to be achieved via the hopping mechanism, and hollow interspaces minimize transport resistance. These features, as demonstrated using SNP-embedded multishell hollow MOFs with up to five shells, lead to high electrochemical performances including high volumetric capacities and low overpotentials in Li-O2 batteries.

12.
Contemp Clin Trials Commun ; 17: 100523, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32025585

RESUMO

BACKGROUND: /Purpose: Long-stenting, even with a second-generation drug-eluting stent (DES), is an independent predictor of restenosis and stent thrombosis in patients with long coronary lesions. Spot-stenting, i.e., selective stenting of only the most severe stenotic segments of a long lesion, may be an alternative to a DES. The purpose of this study is to compare the one-year clinical outcomes of patients with spot versus entire stenting in long coronary lesions using a second-generation DES. METHOD: This study is a randomized, prospective, multi-center trial comparing long-term clinical outcomes of angiography-guided spot versus entire stenting in patients with long coronary lesions (≥25 mm in length). The primary endpoint is target vessel failure (TVF) at 12 months, a composite of cardiac death, target vessel-related myocardial infarction, and target vessel revascularization (TVR). A total of 470 patients are enrolled for this study according to sample size calculations. This study will be conducted to evaluate the non-inferiority of spot stenting compared to entire stenting with zotarolimus-eluting stents (ZES). RESULTS: This study is designed to evaluate the clinical impact of spot-stenting with ZESs for TVF due to possible edge restenosis or non-target lesion revascularization. Theoretically, spot-stenting may decrease the risk of TVR and the extent of endothelial dysfunction. CONCLUSION: This SPOT trial will provide clinical insight into spot-stenting with a current second-generation DES as a new strategy for long coronary lesions.

13.
ACS Appl Mater Interfaces ; 11(47): 44366-44374, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31670934

RESUMO

A cobalt-phosphate (Co-Pi) catalyst having octahedral CoO6 molecular units as reaction sites is a key component in photoelectrochemical (PEC) water oxidation systems, but its limited adsorption sites for oxygen-evolving intermediates (*OH, *OOH), slow charge transfer rates, and fast degradation of reaction sites are yet to be overcome. Here, we report that Co-Pi nanoparticles with low-coordinate Co ions and doped nitrogen atoms could be decorated on hematite nanorod arrays to form N-CoPi/hematite composites. Moreover, the local atomic configuration and bond distance studies show that trivalent Co3+ states are partially reduced through nitrogen radicals in the plasma to low-coordinate bivalent Co2+ states playing as the facile adsorption sites of oxygen-evolving intermediates due to the decreased activation barrier for water oxidation. Electron transport is also reinforced by nitrogen species due to the formation of hybridizing N 2p orbitals that give the acceptor levels in the bandgap. As a result, both the incident photon-to-electron conversion efficiency and the charge transfer resistance on N-CoPi/hematite outperform those on a bare hematite by about 3 fold. Furthermore, N-CoPi/hematite gives high activity retention over 90% after the long operation of water oxidation, in support of the reaction sites on N-CoPi not degrading during the successive water oxidation.

14.
Small ; 15(19): e1804764, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30884157

RESUMO

An electrocatalyst for oxygen evolution reaction (OER) is essential in the realization of renewable energy conversion technologies, but its large overpotential, slow charge transfer, and degradation of surface reaction sites are yet to be overcome. Here, it is found that the metallic nickel domains and high-valence reduced molybdenum ions of NiFeMo electrocatalysts grown on a 3D conductive and porous electrode without using binders enable ultrahigh performance in OER. High resolution-transmission electron microscope and extended X-ray absorption fine structure analyses show that metallic nickel domains with Ni-Ni bonds are generated on the catalyst surface via a dry synthesis using nitrogen plasma. Also, Mo K-edge X-ray absorption near-edge spectroscopy reveals that Mo6+ ions are reduced into high-valence modulating Mo4+ ions. With the metallic nickel domains facilitating the adsorption of oxygen intermediates to low-coordinated Ni0 and the Mo4+ pulling their electrons, the catalyst exhibits about 60-fold higher activity than a Mo-free NiFe catalyst, while giving about threefold faster charge transfer along with longer stability over 100 h and repeated 100 cycles compared to a bare NiFeMo catalyst. Additionally, these metallic domains and high-valence modulating metal ions are exhibited to give high Faradaic efficiency over 95%.

15.
J Exerc Rehabil ; 14(3): 436-444, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30018931

RESUMO

The objective of this study was to investigate the changes in the muscle activation of high school and college baseball pitchers during throwing of the ball with maximum effort (TBME) using a regular baseball (RB) subsequent to using a light baseball (LB), RB, and overweight baseball (OB) during warm-up (WU) and the resulting changes in the pitch velocity. The study aimed to use the findings in providing basic data for a training program designed to increase the pitch velocity of baseball pitchers. The study population consisted of 12 high school and college baseball players. The study measured and analyzed the upper extremity muscle activation and ball velocity in the stride, arm cocking, and acceleration phases during TBME using an RB subsequent to using an LB, RB, and OB during WU. During WU, the ball velocity was higher when pitching with an LB than with an RB or OB and when pitching with an RB than with an OB. However, there were no significant differences in the ball velocity when pitching with an RB during TBME. In conclusion, WU using weighted baseballs resulted in varying muscle activations, and although the velocity decreased when pitching with an OB, no difference was found during TBME using an RB. Therefore, it is believed that using weighted baseballs during WU does not have an effect on the ball velocity during TBME; future studies are needed on the effects through long-term training.

16.
J Phys Ther Sci ; 29(4): 605-608, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28533593

RESUMO

[Purpose] The aim of this study was to investigate the effects of repeated vibratory stimulation to muscles related to hand functions on dexterity, strength, and sensory function in patients with chronic stroke. [Subjects and Methods] A total of 10 stroke patients with hemiplegia participated in this study. They were divided into two groups: a) Experimental and b) Control, with five randomly selected subjects for each group. The experimental group received vibratory stimulation, while the control group received the traditional physical therapy. Both interventions were performed for 30 minutes each session, three times a week for four weeks. [Results] There was a significant within-group improvement in the box and block test results in both groups for dexterity. Grip strength improved in both groups but the improvement was not statistically significant. [Conclusion] The vibratory stimulation activated the biceps brachii and flexor carpi radialis, which increased dexterity to grasp and lift the box and block from the surface. Therefore, repeated vibratory stimulation to muscles related to hand functions improved hand dexterity equality to the traditional physical therapy in patients with chronic stroke.

17.
J Phys Ther Sci ; 29(12): 2103-2106, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29643584

RESUMO

[Purpose] This study aimed to investigate whether a virtual reality (VR) intervention has an influence in improving the motor function and activities of daily living (ADLs) in patients with lesions in different regions of the brain. [Subjects and Methods] Eleven subjects with hemiplegic stroke were recruited in this study, which was conducted from January to February, 2017. They received a VR intervention once a day for 30 min, 5 times a week for 4 weeks. The Fugl-Meyer Assessment (FMA) and the Korean version of the Modified Barthel Index (K-MBI) were used to assess the post-stroke patients' motor function and ADLs, respectively. [Results] There were significant differences in pre- and post-test outcomes of the Arm and Coordination and Speed (CS) in the FMA and K-MBI in the middle cerebral artery group (MCAG). Moreover, there were significant differences in all sub-tests of FMA and K-MBI in the Basal ganglia group (BGG). In addition, there were significant differences in the pre-test outcomes of Arm and pre- and post-test outcomes of Hand in the FMA between the two groups. [Conclusion] This study revealed that VR intervention improved the upper limb motor function and ADLs of post-stroke patients, especially those in the BGG.

18.
ACS Appl Mater Interfaces ; 7(34): 19370-81, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26264641

RESUMO

Integrating a nanostructured carbon array on a conductive substrate remains a challenging task that presently relies primarily on high-vacuum deposition technology. To overcome the problems associated with current vacuum techniques, we demonstrate the formation of an N-doped carbon array by pyrolysis of a polymer array that was electrochemically grown on carbon fiber paper. The resulting carbon array was investigated for use as a supercapacitor electrode. In-depth surface characterization results revealed that the microtextural properties, surface functionalities, and degree of nitrogen incorporated into the N-doped carbon array can be delicately controlled by manipulating carbonization temperatures. Furthermore, electrochemical measurements showed that subtle changes in these physical properties resulted in significant changes in the capacitive behavior of the N-doped carbon array. Pore structures and nitrogen/oxygen functional groups, which are favorable for charge storage, were formed at low carbonization temperatures. This result showed the importance of having a comprehensive understanding of how the surface characteristics of carbon affect its capacitive performance. When utilized as a substrate in a pseudocapacitive electrode material, the N-doped carbon array maximizes capacitive performance by simultaneously achieving high gravimetric and areal capacitances due to its large surface area and high electrical conductivity.

19.
J Invasive Cardiol ; 27(8): 346-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26232010

RESUMO

BACKGROUND: The prognostic value of poststent fractional flow reserve (FFR) has not been clearly defined in patients with drug-eluting stent (DES) implantation. This study sought to evaluate the association between FFR and clinical outcomes after DES implantation with intravascular ultrasound (IVUS) assistance. METHODS: A total of 115 lesions (107 patients) with FFR measurement after IVUS-assisted DES implantation were enrolled. Poststent angiographic and IVUS parameters were compared with FFR values. Clinical outcomes were assessed by target vessel failure (TVF), defined as a composite of target vessel revascularization, death, or non-fatal myocardial infarction attributed to the target vessel. RESULTS: Mean poststent FFR was 0.92 ± 0.04. Minimal stent area by IVUS had a positive correlation with poststent FFR (r = 0.36; P<.01). Poststent FFR ≥0.89 was a physiologic cut-off value for 1-year TVF-free survival. The best cut-off value of minimal stent area to define poststent FFR ≥0.89 was >5.4 mm² (sensitivity, 63.2%; specificity, 90.0%). At 3-year follow-up, lesions with poststent FFR ≥0.89 had a better TVF-free survival rate than those with poststent FFR <0.89 (89.3% vs 61.1%, P =.03). CONCLUSION: Poststent FFR can be a useful predictor for long-term clinical outcomes after DES implantation and relevant to IVUS minimal stent area.


Assuntos
Doença da Artéria Coronariana/cirurgia , Vasos Coronários/fisiopatologia , Stents Farmacológicos , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Intervenção Coronária Percutânea/métodos , Cirurgia Assistida por Computador/métodos , Ultrassonografia de Intervenção , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
20.
J Exerc Rehabil ; 11(1): 30-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25830141

RESUMO

The purpose of this study was to design a repeatable universal rehabilitation program in which patients with hemiplegia can participate voluntarily, complementing physical and occupational therapies to increase voluntary exercise practice rate. Also, this study attempted to identify the relationship between psychological resilience due to the implementation of self-bedside exercise and functional recovery of activity of daily living (ADL). 12 patients with hemiplegia voluntarily participated in 8 weeks of self-bedside exercise 5 times a day and more than 5 days a week. Their program implementation, resilience, activities of daily living (MBI), upper limb motor functions (MFT), and balance ability (BBS) were analyzed and compared before and after the program. Compared to before implementing the program, significant increases were found in resilience, MBI, BBS, and MFT in the affected side after the implementation, and the resilience scores showed statistically positive correlation in MBI and MFT. Also, the change in resilience before and after the program implementation showed a statistically positive correlation. Therefore, it can be concluded that the self-bedside exercise developed in this study had a positive effect on voluntary participation in exercise as well as resilience and ADL. However, many studies which complement the psychological aspects of hemiparetic patients with stroke are still needed.

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