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1.
J Youth Adolesc ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937330

RESUMEN

Previous research has predominantly relied on single-informant reports to establish the association between parental control and children's anxiety. However, there remains ambiguity regarding the extent to which discrepancies in parent-child reports of parental control are related to children anxiety. This study examined parent-child perceived discrepancies in parental control and their association with children's anxiety, along with the moderated effect of parent-child closeness through cross-sectional and prospective analysis. The sample consisted of 790 children (Mage = 11.34, SD = 6.73, 45.60% for girls), with 741 father-child dyads and 760 mother-child dyads included. Data were analyzed using polynomial regressions with response surface analysis. The results indicated that children tended to perceive higher levels of parental psychological control and lower levels of behavioral control compared to their parents' perceptions. In the cross-sectional analysis, a significant association between greater incongruence in psychological/behavioral control and higher levels of children's anxiety at T1 was observed exclusively in father-child dyads. In prospective analysis, for both father-child and mother-child dyads, congruence in higher levels of psychological control was associated with higher levels of children's anxiety at T2, while congruence in higher levels of behavioral control was associated with lower levels of children's anxiety at T2. Additionally, greater incongruence in psychological/behavioral control was linked to higher levels of children's anxiety at T2. Furthermore, mother-child closeness emerged as a significant moderator such that perceived incongruence in psychological/behavioral control could not affect children's anxiety at T2 in the high mother-child closeness condition. These findings highlight the significance of considering parent-child congruence and incongruence when examining the impact of parental control on children's anxiety.

2.
Angew Chem Int Ed Engl ; : e202407665, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837634

RESUMEN

Bismuth-based materials have emerged as promising catalysts in the electrocatalytic reduction of CO2 to formate. However, the reasons for the reconstruction of Bi-based precursors to form bismuth nanosheets are still puzzling, especially the formation of defective bismuth sites. Herein, we prepare bismuth nanosheets with vacancy-rich defects (V-Bi NS) by rapidly reconstructing Bi19Cl3S27 under negative potential. Theoretical analysis reveals that the introduction of chlorine induces the generation of intrinsic electric field in the precursor, thereby increasing the electron transfer rate and further promoting the metallization of trivalent bismuth. Meanwhile, in situ Raman and ex situ XRD tests verify that Bi19Cl3S27 has a faster reconstruction rate than Bi2S3. The formed V-Bi NS exhibits up to 96% HCOO- Faraday efficiency and 400 mA cm-2 HCOO- partial current densities, and its ECSA normalized formate current density and yield are 2.2 times higher than those of intact bismuth nanosheets (I-Bi NS). Density functional theory (DFT) calculations indicate that bismuth vacancies with electron-rich aggregation reduce the activation energy of CO2 to *CO2- radicals and stabilize the adsorption of the key intermediate *OCHO, thus facilitating the reaction kinetics of formate production.

3.
Small ; 19(17): e2207425, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36703521

RESUMEN

Urea-assisted hybrid water splitting is a promising technology for hydrogen (H2 ) production, but the lack of cost-effective electrocatalysts hinders its extensive application. Herein, it is reported that Nitrogen-doped Co9 S8 /Ni3 S2 hybrid nanosheet arrays on nickel foam (N-Co9 S8 /Ni3 S2 /NF) can act as an active and robust bifunctional catalyst for both urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), which could drive an ultrahigh current density of 400 mA cm-2 at a low working potential of 1.47 V versus RHE for UOR, and gives a low overpotential of 111 mV to reach 10 mA cm-2 toward HER. Further, a hybrid water electrolysis cell utilizing the synthesized N-Co9 S8 /Ni3 S2 /NF electrode as both the cathode and anode displays a low cell voltage of 1.40 V to reach 10 mA cm-2 , which can be powered by an AA battery with a nominal voltage of 1.5 V. The density functional theory (DFT) calculations decipher that N-doped heterointerfaces can synergistically optimize Gibbs free energy of hydrogen and urea, thus accelerating the catalytic kinetics of HER and UOR. This work significantly advances the development of the promising cobalt-nickel-based sulfide as a bifunctional electrocatalyst for energy-saving electrolytic H2 production and urea-rich innocent wastewater treatment.

4.
Small ; 19(35): e2301986, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37096917

RESUMEN

Glycerol-assisted hybrid water electrolysis is a potential strategy to achieve energy-efficient hydrogen production. However, the design of an efficient catalyst for the specific reaction is still a key challenge, which suffers from the barrier of regulating the adsorption characteristics of distinctive intermediates in different reactions. Herein, a novel rationale that achieves selective adsorption behavior modulation for self-supported nickel selenide electrode by heteroatom implantation and heterointerface construction through electrodeposition is developed, which can realize nichetargeting optimization on hydrogen evolution reaction (HER) and glycerol oxidation reaction (GOR), respectively. Specifically, the prepared Mo-doped Ni3 Se2 electrode exhibits superior catalytic activity for HER, while the NiSe-Ni3 Se2 electrode exhibits high Faradaic efficiency (FE) towards formate production for GOR. A two-electrode electrolyzer exhibits superb activity that only needs an ultralow cell voltage of 1.40 V to achieve 40 mA cm-2 with a high FE (97%) for formate production. Theoretical calculation unravels that the introduction of molybdenum contributes to the deviation of the d-band center of Ni3 Se2 from the Fermi level, which is conducive to hydrogen desorption. Meanwhile, the construction of the heterojunction induces the distortion of the surface structure of nickel selenide, which exposes highly active nickel sites for glycerol adsorption, thus contributing to the excellent electrocatalytic performance.

5.
Cell Mol Biol (Noisy-le-grand) ; 69(14): 137-142, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38279459

RESUMEN

This study aimed to investigate the effect of thalidomide (Thal) regulating microRNA (miR)-524-5p/follistatin-like protein 1 (FSTL1) on the invasion ability of gastric cancer cells. For this purpose, real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the level of miR-524-5p in GES1, SUN-16, MGC-803, SGC-7901, MKN-28, and MKN-45 cells. Then the MGC-803 and MKN-45 cells would proceed to the next research. The MGC-803 and MKN-45 cells were cultured in vitro and added Thal to the final concentration of (6.25, 12.5, 25, 50, 100) µg/mL. The blank control group only added 0.1% dimethyl sulfoxide (DMSO) culture medium, and cultured for 48 hours. CCK8 was used to detect cell proliferation, and Transwell was used to detect cell invasion. The experiment was divided into a blank control group, Thal group (25 µg/mL Thal-treated cells), Thal+inhibitor NC group, and Thal+miR-524-5p inhibitor group (transfected with inhibitor NC and miR-524-5p inhibitor respectively on the basis of Thal group), cultivated for 48 h. The level of miR-524-5p in the cells was detected by RT-qPCR; the cell invasion was detected by Transwell; the expression of matrix metalloproteinase (MMP)-2, MMP-9, FSTL1 protein in the cells was detected by Western blot. The targeting relationship between miR-524-5p and FSTL1 was verified by dual luciferase. Results showed that compared with GES1 cells, the level of miR-524-5p in SUN-16, MGC-803, SGC-7901, MKN-28, and MKN-45 cells decreased (P<0.05). In MGC-803 and MKN-45 cells, compared with the blank control group, the cell proliferation rate and the number of invasions in the (50, 100) µg/mL Thal treatment groups, and the number of invasions in (6.25, 12.5, 25) µg/mL Thal treatment groups decreased (P<0.05). Compared with the blank control group, the level of miR-524-5p in the cells of the Thal group, Thal+inhibitor NC group, and Thal+miR-524-5p inhibitor group increased (P<0.05), the number of invasions, the levels of MMP-2, MMP-9 and FSTL1 proteins in cells decreased (P<0.05); compared with the Thal group and the Thal+inhibitor NC group, the level of miR-524-5p in the cells of the Thal+miR-524-5p inhibitor group decreased (P<0.05), the number of invasions, the levels of MMP-2, MMP-9, and FSTL1 proteins in the cells increased (P<0.05). Dual luciferase verification revealed that there was a targeting relationship between miR-524-5p and FSTL1. In conclusion, that can up-regulate the expression of miR-524-5p to reduce the expression of FSTL1 protein, inhibit the invasion of gastric cancer cells, and achieve alleviation of the disease.


Asunto(s)
Proteínas Relacionadas con la Folistatina , MicroARNs , Neoplasias Gástricas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Talidomida/farmacología , Movimiento Celular , Proliferación Celular/fisiología , Línea Celular Tumoral , Luciferasas/metabolismo
6.
Clin Orthop Relat Res ; 481(7): 1399-1411, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36728053

RESUMEN

BACKGROUND: Ankylosing spondylitis-related cervical spine fracture with neurologic impairment (ASCF-NI) is a rare but often lethal injury. Factors independently associated with survival after treatment remain poorly defined, and identifying patients who are likely to survive the injury remains challenging. QUESTIONS/PURPOSES: (1) What factors are independently associated with survival after treatment among patients with ASCF-NI? (2) Can a nomogram be developed that is sufficiently simple for clinicians to use that can identify patients who are the most likely to survive after injury? METHODS: This retrospective study was conducted based on a multi-institutional group of patients admitted and treated at one of 29 tertiary hospitals in China between March 1, 2003, and July 31, 2019. A total of 363 patients with a mean age of 53 ± 12 years were eventually included, 343 of whom were male. According to the National Household Registration Management System, 17% (61 of 363) died within 5 years of injury. Patients were treated using nonsurgical treatment or surgery, including procedures using the anterior approach, posterior approach, or combined anterior and posterior approaches. Indications for surgery included three-column injury, unstable fracture displacement, neurologic impairment or continuous progress, and intervertebral disc incarceration. By contrast, patients generally received nonsurgical treatment when they had a relatively stable fracture or medical conditions that did not tolerate surgery. Demographic, clinical, and treatment data were collected. The primary study goal was to identify which factors are independently associated with death within 5 years of injury, and the secondary goal was the development of a clinically applicable nomogram. We developed a multivariable Cox hazards regression model, and independent risk factors were defined by backward stepwise selection with the Akaike information criterion. We used these factors to create a nomogram using a multivariate Cox proportional hazards regression analysis. RESULTS: After controlling for potentially confounding variables, we found the following factors were independently associated with a lower likelihood of survival after injury: lower fracture site, more-severe peri-injury complications, poorer American Spinal Injury Association (ASIA) Impairment Scale, and treatment methods. We found that a C5 to C7 or T1 fracture (ref: C1 to C4 and 5; hazard ratio 1.7 [95% confidence interval 0.9 to 3.5]; p = 0.12), moderate peri-injury complications (ref: absence of or mild complications; HR 6.0 [95% CI 2.3 to 16.0]; p < 0.001), severe peri-injury complications (ref: absence of or mild complications; HR 30.0 [95% CI 11.5 to 78.3]; p < 0.001), ASIA Grade A (ref: ASIA Grade D; HR 2.8 [95% CI 1.1 to 7.0]; p = 0.03), anterior approach (ref: nonsurgical treatment; HR 0.5 [95% CI 0.2 to 1.0]; p = 0.04), posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.8]; p = 0.006), and combined anterior and posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.9]; p = 0.02) were associated with survival. Based on these factors, a nomogram was developed to predict the survival of patients with ASCF-NI after treatment. Tests revealed that the developed nomogram had good performance (C statistic of 0.91). CONCLUSION: The nomogram developed in this study will allow us to classify patients with different mortality risk levels into groups. This, coupled with the factors we identified, was independently associated with survival, and can be used to guide more appropriate treatment and care strategies for patients with ASCF-NI. LEVEL OF EVIDENCE: Level III, therapeutic study.


Asunto(s)
Fracturas Óseas , Enfermedades del Sistema Nervioso , Fracturas de la Columna Vertebral , Espondilitis Anquilosante , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Femenino , Nomogramas , Espondilitis Anquilosante/complicaciones , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/terapia , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/terapia
7.
Sensors (Basel) ; 23(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37299797

RESUMEN

When the initial size of an atom cloud in a cold atom interferometer is negligible compared to its size after free expansion, the interferometer is approximated to a point-source interferometer and is sensitive to rotational movements by introducing an additional phase shear in the interference sequence. This sensitivity on rotation enables a vertical atom-fountain interferometer to measure angular velocity in addition to gravitational acceleration, which it is conventionally used to measure. The accuracy and precision of the angular velocity measurement depends on proper extraction of frequency and phase from spatial interference patterns detected via the imaging of the atom cloud, which is usually affected by various systematic biases and noise. To improve the measurement, a pre-fitting process based on principal component analysis is applied to the recorded raw images. The contrast of interference patterns are enhanced by 7-12 dB when the processing is present, which leads to an enhancement in the precision of angular velocity measurements from 6.3 µrad/s to 3.3 µrad/s. This technique is applicable in various instruments that involve precise extraction of frequency and phase from a spatial interference pattern.


Asunto(s)
Aceleración , Movimiento , Rotación , Diagnóstico por Imagen
8.
Angew Chem Int Ed Engl ; 62(26): e202302241, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37114658

RESUMEN

Electrochemical conversion of CO2 to highly valuable ethanol has been considered a intriguring strategy for carbon neutruality. However, the slow kinetics of coupling carbon-carbon (C-C) bonds, especially the low selectivity ethanol than ethylene in neutral conditions, is a significant challenge. Herein, the asymmetrical refinement structure with enhanced charge polarization is built in the vertically oriented bimetallic organic frameworks (NiCu-MOF) nanorod array with encapsulated Cu2 O (Cu2 O@MOF/CF), which can induce an intensive internal electric field to increase the C-C coupling for producing ethanol in neutral electrolyte. Particularly, when directly employed Cu2 O@MOF/CF as the self-supporting electrode, the ethanol faradaic efficiency (FEethanol ) could reach maximum 44.3 % with an energy efficiency of 27 % at a low working-potential of -0.615 V versus the reversible hydrogen electrode (vs. RHE) using CO2 -saturated 0.5 M KHCO3 as the electrolyte. Experimental and theoretical studies suggest that the polarization of atomically localized electric fields derived from the asymmetric electron distribution can tune the moderate adsorption of *CO to assist the C-C coupling and reduce the formation energy of H2 CCHO*-to-*OCHCH3 for the generation of ethanol. Our research offers a reference for the design of highly active and selective electrocatalysts for reducing CO2 to multicarbon chemicals.


Asunto(s)
Dióxido de Carbono , Carbono , Adsorción , Electricidad , Etanol
9.
Angew Chem Int Ed Engl ; 62(31): e202304562, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37253663

RESUMEN

Photocatalytic CO2 reduction (PCR) expresses great attraction to convert useless greenhouse gas into valuable chemical feedstock. However, the weak interactions between catalytic sites and PCR intermediates constrains the PCR activity and selectivity. Herein, we proposed a new strategy to match the intermediates due to the maximum orbital overlap of catalytic sites and C1 intermediates by establishing dual Jahn-Teller (J-T) sites, in which, the strongly asymmetric J-T sites can break the nonpolar CO2 molecules and self-adapt the different structure of C1 intermediates. Taking cobalt carbonate hydroxide as an example, the weakly symmetric dual cobalt (Co2 ) dual J-T sites, weakly asymmetric Fe&Co sites and strongly asymmetric Cu&Co sites were assembled. After illumination, the interaction between dual J-T sites and the CO2 molecules enhances J-T distortion, which further modulates the PCR activity and selectivity. As a result, the Cu&Co sites exhibited CO yield of 8137.9 µmol g-1 , about 2.3-fold and 4.2-fold higher than that of the Fe&Co and Co2 sites within 5-hour photoreaction, respectively. In addition, the selectivity achieved as high as 92.62 % than Fe&Co (88.67 %) and Co2 sites (55.33 %). This work provides a novel design concept for the construction of dual J-T sites to regulate the catalytic activity and selectivity.

10.
Small ; 18(20): e2200242, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35434924

RESUMEN

Hydrazine-assisted hybrid water electrolysis is an energy-saving approach to produce high-purity hydrogen, whereas the development of pH-universal bifunctional catalysts encounters a grand challenge. Herein, a phase-selective synthesis of ruthenium phosphide compounds hybrid with carbon forming pancake-like particles (denoted as Rux P/C-PAN, x = 1 or 2) is presented. The obtained RuP/C-PAN exhibits the highest catalytic activity among the control samples, delivering ultralow cell voltages of 0.03, 0.27, and 0.65 V to drive 10 mA cm-2 using hybrid water electrolysis corresponding to pH values of 14, 7, and 0, respectively. Theoretical calculation deciphers that the RuP phase displays optimized free energy for hydrogen adsorption and reduced energy barrier for hydrazine dehydrogenation. This work may not only open up a new avenue in exploring universally compatible catalyst to transcend the limitation on the pH value of electrolytes, but also push forward the development of an energy-saving hydrogen generation technique based on emerging hybrid water electrolysis.


Asunto(s)
Rutenio , Agua , Electrólisis , Hidrazinas , Hidrógeno , Concentración de Iones de Hidrógeno
11.
Opt Express ; 30(12): 22088-22096, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224915

RESUMEN

In an atomic fountain, atoms in motion can be spatially separated into discrete Zeeman sub-states by magnetically induced Stern-Gerlach effect. With resonant light pulses acting as a shutter, specific states are selected for subsequent experiments. Such separation-selection process in atomic optics is the analogue of a spatial filter in physical optics which selects and purifies the modes of light. This technique is demonstrated by injecting a pulsed current in a circular coil around a vertical atomic fountain, separating the pre-cooled Rubidium atoms by a distance of centimeters in between, and filtering each single sub-state with block pulses. The filtered atoms after the process is highly purified in the desired sub-state. The apparatus of the atomic spatial filter is adaptable in atomic optics and can be integrated into the high-vacuum chamber of an atomic fountain.

12.
J Nanosci Nanotechnol ; 19(6): 3487-3494, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30744776

RESUMEN

An environment-friendly non-chromium chemical conversion coating was obtained from fluozirconate/fluotitanate acidic solution for the corrosion protection of AA 5083. The surface morphology, composition, electrochemical behavior and corrosion resistance of this coating were investigated. The coating was found to be a homogeneous and dense layer consisting of nano-size particles, of which the major component was compound oxides consisted by Al, Mg, Zr, Ti, F and O. The results of electrochemical measurements, immersion and natural salt spray (NSS) tests demonstrated that the corrosion resistance of the AA 5083 H-116 was improved by the nano-sized non-chromium chemical conversion coating considerably, which was most attributed to the great inhibitive action on the anodic dissolution by acting as a protective barrier layer.

13.
Arch Phys Med Rehabil ; 100(10): 1872-1880, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30684486

RESUMEN

OBJECTIVE: To assess the survival and the predictors of mortality in patients with severe cervical spinal cord injuries (CSCI). DESIGN: Retrospective study. PARTICIPANTS: From January 1, 2010, to May 31, 2018, patients who suffered from severe CSCIs in Western China were enrolled in this study (N=222). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Survival rates and mortality risk factors. Measures were calculated by the product-limit method (Kaplan-Meier) and the Cox model. RESULTS: The overall 1-year, 3-year, 5-year, and 8-year postoperative mortalities were 24.4%, 30.6%, 33.3%, 36.2%, and 39.0%, respectively. Most deaths occurred within 36 months after the injury. According to the Cox proportional hazards model, the significant predictors of survival were as follows: (1) age; (2) neurologic level; (3) treatment options (surgical or conservative); (4) ventilator support (P<.05). The 8-year mortality for older patients (>50y) was 50.2%, which was significantly higher than that for younger patients (32.4%, <50y). The risk of death was 2.053 times higher in higher levels of injury (C1-C4) than in lower levels of injury (C5-C8) (P<.05). Compared with conservative treatment, patients who received surgical treatment (either anterior or posterior decompression) had a lower risk of death (P<.05). No significant difference was detected in the risk of death between early surgery (<3d) and mid-term surgery (3-7d) (P>.05). However, patients who received late-term surgery (>7d) had a higher mortality risk (P<.05). The overall 8-year mortality risk of patients who needed ventilator support was much higher than those who did not need ventilator support (P<.05). CONCLUSIONS: Age, neurologic level, ventilator dependence, treatment options, and timing to surgery were main risk factors for mortality in patients with severe CSCIs. Better understanding of the predictors for survival could possibly contribute to the improvement of survival rates.


Asunto(s)
Vértebras Cervicales/lesiones , Traumatismos de la Médula Espinal/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Vértebras Cervicales/cirugía , China/epidemiología , Tratamiento Conservador , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Modelos de Riesgos Proporcionales , Respiración Artificial , Estudios Retrospectivos , Factores de Riesgo , Traumatismos de la Médula Espinal/terapia , Tasa de Supervivencia , Tiempo de Tratamiento , Adulto Joven
14.
Med Sci Monit ; 24: 2252-2258, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29656299

RESUMEN

BACKGROUND Our study explored the influences of hydration conditions and loading methods on the mechanical properties of cortical bones and cancellous bones. MATERIAL AND METHODS Elastic modulus and hardness of human cortical bones and cancellous bones that contained different moisture levels (20%, 30%, 40%, 50%, and 60%) were measured with nanoindentation with different peak loads and loading rates. Cortical bones with 20% and 60% moisture were tested with 30 nm, 40 nm, and 50 nm peak loads at 6 nm/s, 8 nm/s, and 10 nm/s loading rates, respectively. Cancellous bones with 5% or 40% moisture percentages were tested with 600 µN, 750 µN, and 1000 µN peak loads at 200 µN/s, 250 µN/s, and 333 µN/s loading rates, respectively. RESULTS Under the same loading condition, specimens with higher moisture contents showed decreased elastic modulus and hardness. Under different loading conditions, the loading modes had little influence on elastic modulus and hardness of cortical bone and cancellous bone with low moisture, but had significant influence on specimens with higher moistures. CONCLUSIONS The elastic modulus and bone hardness were affected by the moisture content and the loading conditions in cortical and cancellous bones with high hydration condition but not in those with low hydration condition.


Asunto(s)
Hueso Esponjoso/fisiología , Hueso Cortical/fisiología , Fenómenos Biomecánicos/fisiología , Agua Corporal/metabolismo , Agua Corporal/fisiología , Huesos/fisiología , Hueso Esponjoso/patología , Hueso Cortical/patología , Módulo de Elasticidad/fisiología , Dureza/fisiología , Humanos , Análisis Espectral , Soporte de Peso/fisiología
15.
Inorg Chem ; 56(7): 3742-3753, 2017 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-28304161

RESUMEN

Three thermally activated delayed fluorescence cationic cuprous complexes [Cu(POP) (ECAF)]PF6 (1, POP = bis(2-diphenylphosphinophenyl)ether, ECAF = 9,9-bis(9-ethylcarbazol-3-yl)-4,5-diazafluorene), [Cu(POP) (EHCAF)]PF6 (2, EHCAF = 9,9-bis(9-ethylhexylcarbazol-3-yl)-4,5-diazafluorene), and [Cu(POP) (PCAF)]PF6 (3, PCAF = 9,9-bis(9-phenylcarbazaol-3-yl)-4,5-diazafluorene) with bipolar 4,5-diazafluorene ligand substituted by bis-carbazole have been successfully prepared, and their UV absorption, photoluminescent properties, and electrochemical behaviors were investigated. At room temperature, complexes 1, 2, and 3 exhibit efficient yellowish-green emission with peak maxima of 550, 549, and 556 nm, respectively, and lifetimes of 5.7 µs. In powder states, the quantum yields (ϕPL) of 22.4% for 1, 18.5% for 2, and 20.0% for 3, respectively, are found. These metal phosphors can be vacuum-evaporated and applied in the organic light-emitting diodes (OLEDs) of indium tin oxide/poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (40 nm)/4,4',4″-tri(9-carbazoyl)triphenylamine (15 nm)/cuprous complexes (10 wt %): 1,3-bis(9-carbazolyl)benzene (30 nm)/1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene (50 nm)/LiF (0.5 nm)/Al (100 nm). Complex 1-based device D1 achieved a maximum luminance of 11 010 cd m-2, a current efficiency of 47.03 cd A-1, and an external quantum efficiency of 14.81%. The high electroluminescence efficiencies of these complexes are assumed to be due to their good thermal stabilities and capture of both singlet and triplet excitons. The research presented here provides a powerful tool toward highly efficient and cheap OLED devices.

16.
J Spinal Disord Tech ; 28(3): E166-72, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25353202

RESUMEN

STUDY DESIGN: A novel total cervical prosthesis (TCP) for single-level cervical subtotal corpectomy was assessed in a caprine animal model. OBJECTIVES: To investigate the radiologic and histomorphometric characteristics of a novel TCP for single-level cervical subtotal corpectomy. SUMMARY OF BACKGROUND: Cervical disk replacement has emerged as a promising alternative to arthrodesis in the management of cervical disk herniation. However, they are designed for anterior cervical discectomy, and not suitable for cervical subtotal corpectomy. To solve this problem, our group has developed a novel TCP for single-level cervical subtotal corpectomy. MATERIALS AND METHODS: There were 12 adult Shannxi goats (2 y old) used in this study. The goats were divided into 2 groups based on postoperative survival periods of 3 (n=6) and 6 (n=6) months after surgery. Using an anterior surgical approach, a standard anterior C3 vertebra subtotal corpectomy and decompression of the spinal canal were performed, followed by implantation of the TCP device. Then all the goats were killed and underwent radiographic and histologic observations. RESULTS: The TCP implant procedures were successfully completed in all 12 goats without incidence of vascular or infectious complications. The range of motion of C2-C3 and C3-C4 segments were preserved in both of the groups. Three-dimensional images of specimens interface indicated confluent interdigitization of trabeculae at the prosthetic endplate-bone interface, without evidence of significant radiolucent lines or gaps. Histomorphometric analysis showed that there were a large number of fibrous tissue and a small amount of cartilage cells between the prostheses and bone in the 3 months' group. In the 6 months' group, part of fibrous tissue has changed into the cartilage tissue. CONCLUSIONS: Our data show that this prosthesis can maintain the stability of the cervical spine and retain the activity of the cervical spine in vivo. The findings in this study provide a foundation for ongoing clinical investigations using the TCP.


Asunto(s)
Vértebras Cervicales/cirugía , Discectomía/métodos , Disco Intervertebral/cirugía , Implantación de Prótesis , Animales , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/patología , Descompresión Quirúrgica , Cabras , Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/patología , Modelos Animales , Radiografía , Rango del Movimiento Articular
17.
Adv Mater ; : e2401694, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721895

RESUMEN

Hydrazine oxidation-assisted water splitting is a critical technology to tackle the high energy consumption in large-scale H2 production. Ru-based electrocatalysts hold promise for synergetic hydrogen reduction (HER) and hydrazine oxidation (HzOR) catalysis but are hindered by excessive superficial adsorption of reactant intermediate. Herein, this work designs Ru cluster anchoring on NiFe-LDH (denoted as Ruc/NiFe-LDH), which effectively enhances the intermediate adsorption capacity of Ru by constructing Ru─O─Ni/Fe bridges. Notably, it achieves an industrial current density of 1 A cm-2 at an unprecedentedly low voltage of 0.43 V, saving 3.94 kWh m-3 H2 in energy, and exhibits remarkable stability over 120 h at a high current density of 5 A cm-2. Advanced characterizations and theoretical calculation reveal that the presence of Ru─O─Ni/Fe bridges widens the d-band width (Wd) of the Ru cluster, leading to a lower d-band center and higher electron occupation on antibonding orbitals, thereby facilitating moderate adsorption energy and enhanced catalytic activity of Ru.

18.
Nat Commun ; 15(1): 5172, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890306

RESUMEN

The carbon-carbon coupling at the Cu/Cu2O Schottky interface has been widely recognized as a promising approach for electrocatalytic CO2 conversion into value-added alcohols. However, the limited selectivity of C2+ alcohols persists due to the insufficient control over rectifying interface characteristics required for precise bonding of oxyhydrocarbons. Herein, we present an investigation into the manipulation of the coordination environment of Cu sites through an in-situ electrochemical reconstruction strategy, which indicates that the construction of low-coordinated Cu sites at the Cu/Cu2O interface facilitates the enhanced rectifying interfaces, and induces asymmetric electronic perturbation and faster electron exchange, thereby boosting C-C coupling and bonding oxyhydrocarbons towards the nucleophilic reaction process of *H2CCO-CO. Impressively, the low-coordinated Cu sites at the Cu/Cu2O interface exhibit superior faradic efficiency of 64.15 ± 1.92% and energy efficiency of ~39.32% for C2+ alcohols production, while maintaining stability for over 50 h (faradic efficiency >50%, total current density = 200 mA cm-2) in a flow-cell electrolyzer. Theoretical calculations, operando synchrotron radiation Fourier transform infrared spectroscopy, and Raman experiments decipher that the low-coordinated Cu sites at the Cu/Cu2O interface can enhance the coverage of *CO and adsorption of *CH2CO and CH2CHO, facilitating the formation of C2+ alcohols.

19.
Adv Mater ; 36(4): e2306108, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37815215

RESUMEN

As one of the most promising approaches to producing high-purity hydrogen (H2 ), electrochemical water splitting powered by the renewable energy sources such as solar, wind, and hydroelectric power has attracted considerable interest over the past decade. However, the water electrolysis process is seriously hampered by the sluggish electrode reaction kinetics, especially the four-electron oxygen evolution reaction at the anode side, which induces a high reaction overpotential. Currently, the emerging hybrid electrochemical water splitting strategy is proposed by integrating thermodynamically favorable electro-oxidation reactions with hydrogen evolution reaction at the cathode, providing a new opportunity for energy-efficient H2 production. To achieve highly efficient and cost-effective hybrid water splitting toward large-scale practical H2 production, much work has been continuously done to exploit the alternative anodic oxidation reactions and cutting-edge electrocatalysts. This review will focus on recent developments on electrochemical H2 production coupled with alternative oxidation reactions, including the choice of anodic substrates, the investigation on electrocatalytic materials, and the deep understanding of the underlying reaction mechanisms. Finally, some insights into the scientific challenges now standing in the way of future advancement of the hybrid water electrolysis technique are shared, in the hope of inspiring further innovative efforts in this rapidly growing field.

20.
ACS Appl Mater Interfaces ; 16(26): 33517-33526, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38885354

RESUMEN

Piezoelectric nanogenerators (PENGs) are booming for energy collection and wearable energy supply as one of the next generations of green energy-harvesting devices. Balancing the output, safety, degradation, and cost is the key to solving the bottleneck of PENG application. In this regard, yttrium (Y)-doped zinc oxide (ZnO) (Y-ZnO) was synthesized and embedded into polylactide (PLLA) for developing degradable piezoelectric composite films with an enhanced energy-harvesting performance. The synthesized Y-ZnO exhibits high piezoelectric properties benefiting from the stronger polarity of the Y-O bond and regulation of oxygen vacancy concentration, which improve the output performance of the composite film with Y-ZnO and PLLA (Y-Z-PLLA). The obtained open-circuit voltage (Voc), short-circuit current (Isc), and instantaneous power density of the optimized Y-Z-PLLA PENG reach 17.52 V, 2.45 µA, and 1.76 µW/cm2, respectively. The proposed PENG also shows good degradability. In addition, practical applications of the proposed PENG were demonstrated by converting biomechanical energy, such as walking, running, and jumping, into electricity.

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