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1.
J Colloid Interface Sci ; 624: 88-99, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35660914

RESUMO

Designing highly efficient, long-lasting, and cost-effective cathodic and anodic functional materials as a bifunctional electrocatalyst is essential for overcoming the bottleneck in fuel cell development. Herein, a novel two-step synthesis strategy is developed to synthesize metal-organic framework (MOF) derived nitrogen-doped carbon (NC) with improved spatial isolation and a higher loading amount of cobalt (Co) and nickel carbide (Ni3C) nanocrystal decorated on graphene (denoted as Co@NC-Ni3C/G). Benefiting from multiple active sites of high N-doping level, uniform dispersion of Co and Ni3C nanocrystals, and a large active area of graphene, the Co@NC-Ni3C/G hybrids exhibit excellent methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) efficiency in an alkaline environment. For MOR, the optimized Co@NC-Ni3C/G-350 catalyst achieved a current density of 44.8 mA cm-2 at an applied potential of 1.47 V (V vs. RHE), which is significantly higher than Co@NC-Ni3C (42.07 mA cm-2) and Co@NC (24.1 mA cm-2) in 0.5 M methanol + 1.0 M KOH solutions. In addition, during the CO retention test, the Co@NC-Ni3C/G-350 catalyst exhibits excellent CO tolerance capacity. Excitingly, the as-prepared Co@NC-Ni3C/G-350 hybrid exhibits significantly improved ORR catalytic efficiency in terms of positive onset and half-wave potential (Eonset = 0.90 V, E1/2 = 0.830 V vs. RHE), small Tafel slope (34 mV dec-1) and excellent durability (only reduced 0.016 V after 5000 s test). This work provides new insights into MOF-derived functional nanomaterials for anode and cathode co-catalysts for methanol fuel cells.

2.
J Colloid Interface Sci ; 590: 164-174, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33548600

RESUMO

Interaction of multi-active components can effectively maximize the overall catalytic ability of alcohol fuel cells. Herein, the self-assembled nitrogen doped carbon nanotubes (NCNTs) containing Co-MnO composite (Co-MnO/NCNTs) are successfully synthesized using dihydrodiamine as carbon and nitrogen source through one-step synthesis. In order to further improve the catalytic activity of Co-MnO/NCNTs for alcohol oxidation, small amounts of platinum quantum dots are uniformly loaded on Co-MnO/NCNTs formation of quaternary hybrid (named Pt/Co-MnO/NCNTs) during microwave reduction stage. Notably, the prepared Pt/Co-MnO/NCNTs hybrids possess the excellent methanol and ethanol oxidation mass current density of 1775.4 and 1112.8 mA mg-1 in alkaline condition, which are 3.6 and 2.25 times higher than that of Pt/C catalysts, respectively. The current density of ethanol catalytic oxidation is lower than that of methanol, which may be due to the partial oxidation of acetyl (the intermediate product of ethanol) on the Pt (1 1 1) crystal surface. More importantly, CO oxidation experiments reveal that strong electronic synergistic effect between MnO and Pt quantum dot can greatly improve the CO anti-poisoning ability. Another significant advantage of Pt/Co-MnO/NCNTs is that low platinum loading leads to low cost effective, which demonstrates that the modification non-noble metal catalysts with a few noble metals quantum dots is a promising choice to mass produce high performance catalyst with remarkably boosting electrocatalytic activity for alcohol oxidation.

3.
J Colloid Interface Sci ; 584: 418-428, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33080502

RESUMO

Herein, the ultra-thin layer MoS2 coverd MoO2 nanocrystal arraying on sulfur-doped graphene framework (MoS2-MoO2/3DSG) is obtained via a simple hydrothermal procedure accompanied with high temperature annealing. Sodium thiosulfate and ethanethiol are used as sulfur sources to form three-dimensional sulfur doped graphene (3DSG) in the hydrothermal process. Importantly, MoO2 nano-particles are uniformly loaded on MoS2 nanosheets and 3DSG via in-situ collaborative technology. As a result, the stable conductive network take full use of the characteristics of high specific capacitance of MoO2 nanoparticles, convenient ion transport channel of two-dimensional MoS2 nanoflakes and efficient charge transfer and cross-linked 3DSG to improve the electrochemical activity and enhance the dynamics of electrons / ions, which is up to 1150.37 F g-1 specific capacitance and maintains 94.6% of the original capacitance after 10,000 cycles. Also, FeS2 nanoflowers in situ loading on 3DSG (FeS2/3DSG) with enhanced the overall performance of the device are fabricated. The asymmetric supercapacitor with the positive electrode of MoS2-MoO2/3DSG and the negative electrode of FeS2/3DSG can work efficiently and stably under the voltage of 1.7 V, and provide energy density of 87.38 Wh kg-1 at the power density of 683.94 Wkg-1, displaying an outstanding application prospect for energy storage.

4.
Psychiatry Res ; 274: 189-194, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30807970

RESUMO

We aimed to investigate whether microRNA-let-7d (miRNA-let-7d) and miRNA-107 may serve as diagnostic and therapeutic biomarkers of attention deficit hyperactivity disorder (ADHD). The relative expression level of miRNA-let-7d and miRNA-107 in patients with ADHD and in a healthy control group was detected by real-time polymerase chain reaction. The blood samples were collected at 6 weeks after repetitive transcranial magnetic stimulation (rTMS) or atomoxetine (ATX) in ADHD patients, and the relative expression levels of the two miRNAs before and after treatments were compared. There were significant differences in the expression level of miRNA-let-7d between ADHD patients and healthy children, as well as before and after rTMS or ATX treatment in ADHD patients. However, the expression of miRNA-107 showed no significant difference between ADHD patients and healthy children or before and after rTMS (or ATX treatment). These results suggest that serum miRNA-let-7d may serve as a potential diagnostic and therapeutic biomarker for children with ADHD.


Assuntos
Inibidores da Captação Adrenérgica/uso terapêutico , Cloridrato de Atomoxetina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/sangue , MicroRNAs/sangue , Estimulação Magnética Transcraniana/métodos , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Biomarcadores/sangue , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Resultado do Tratamento
5.
Neuropsychiatr Dis Treat ; 14: 3231-3240, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538481

RESUMO

OBJECTIVE: To explore the effect of repetitive transcranial magnetic stimulation (rTMS) combined with atomoxetine (ATX) in the treatment of attention-deficit hyperactivity disorder (ADHD). METHODS: Sixty-four patients with newly diagnosed ADHD were enrolled from January 2016 to October 2017 from Psychological Centre for Adolescents and Children at 102th Hospital of People's Liberation Army of China. These patients were randomly assigned to three groups according to treatment method: the rTMS group, the ATX group, and the rTMS+ ATX group. Before treatment and 6 weeks after treatment, clinical symptoms and executive functions of ADHD patients were evaluated with the Swanson, Nolan, and Pelham, Version IV (SNAP-IV) Questionnaire, continuous performance test, three subtests (arithmetic, digit span, and coding) of Wechsler Intelligence Scale for Children, as well as Iowa Gambling Tasks (IGT). The effects of treatment were compared among three groups. RESULTS: After 6 weeks of treatment, the scores of all factors in the SNAP-IV questionnaire were lower than those before treatment in the three groups; the scores of three subtests of Wechsler Intelligence Scale for Children, continuous performance test, and IGT were also significantly higher than those before treatment. The rTMS+ ATX group had a better improvement in attention deficits and hyperactivity impulse on the SNAP-IV questionnaire compared with the other groups, and also had a higher efficacy on cold and hot executive functions such as arithmetic, forward numbers, coding, and IGT. In addition, the ATX group performed better than the rTMS group in coding and IGT. CONCLUSION: rTMS, ATX, and the combination therapy are effective in improving core symptoms and executive function in patients with ADHD. The combined treatment has significant therapeutic advantages over the single treatment groups. Compared with rTMS, the drug therapy has a better improvement in coding and IGT.

6.
Sci China Life Sci ; 58(1): 6-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25576450

RESUMO

The activity of Ca(2+)/calmodulin-dependent protein kinase IV (CaMKIV) is sensitive to activity-dependent changes in the level of intracellular Ca(2+). Following neuronal stimulation, the activation of CaMKIV may trigger synaptic modifications and transcriptional responses, both of which are involved in regulating cognitive and emotional behavior. Here, we used CaMKIV knockout (KO) neurons and mice to examine the function of CaMKIV in Ca(2+)-stimulated intracellular signaling and animal behavior, respectively. Following NMDA receptor activation or membrane depolarization, the up-regulation of CREB (cAMP responsive element binding protein) and its target gene Bdnf (brain-derived neurotrophic factor) was intact in cortical neurons obtained from CaMKIV KO mice. CaMKIV KO mice displayed severe impairment in contextual fear memory but normal locomotor activity and anxiety level in the contextual training chamber. Although CaMKIV KO mice showed normal memory in the standard passive avoidance task, they were defective in learning the temporal dissociative passive avoidance task. As indicated by the light/dark test and marble-burying test data, CaMKIV KO mice showed less anxiety and normal perseveration. In the voluntary wheel-running test, CaMKIV KO mice showed normal running time and distance but higher maximal running speed. Our results demonstrate the function of CaMKIV in regulating different forms of fear memory, anxiety, and certain aspect of motor function.


Assuntos
Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/genética , Cálcio/química , Medo/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Transdução de Sinais , Animais , Comportamento Animal , Cálcio/fisiologia , Camundongos , Neurônios/fisiologia , Transdução de Sinais/genética
7.
Int J Behav Med ; 21(4): 730-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24337952

RESUMO

BACKGROUND: A devastating earthquake registering 8.0 on the Richter Scale struck Wenchuan County in Northwest Sichuan Province in China on May 12, 2008, claiming over 69,200 lives, seriously wounding more than 374,600 people, and rendering more than 18,400 people missing. The epicenter was close to Yingxiu Township in Wenchuan County. PURPOSE: This study aimed to investigate the psychosomatic conditions of the children and adolescents exposed to the devastating earthquake and explore the risk factors for psychosomatic symptoms. METHOD: A total of 1,828 participants aged 6 to 16 years, of whom 842 from the affected area and 986 from non-affected area, were administered a Psychosomatic Conditions Scale. RESULTS: Each factor score, total somatic score, total psychological score, and total psychosomatic score of the experimental group were significantly higher than those of the control group (P < 0.001). Positive correlation was found between the psychological state and somatic symptoms in the experimental group(r = 0.157 ~ 0.489, P < 0.01). Respiratory system, cardiovascular system, nervous system, digestive system, urogenital system, emotion, behavior, and language, combined as a panel, were significantly differentiated between the two groups, accounting for 73.4% of the total difference. In the experimental group, the factor scores of anxiety, behavior, total psychological score, and total psychosomatic score of the girls were obviously higher than those of the boys (P < 0.01 ~ 0.05); most somatic factors and psychological factors, total somatic score, total psychological score, and total psychosomatic score of the elder adolescents were significantly higher than those of the younger children (P < 0.01 ~ 0.05). CONCLUSION: The children and adolescents exposed to 5.12 earthquake greatly suffered from terrible psychosomatic conditions, among whom the elder girls had more severe symptoms, particularly in terms of anxiety and behavior.


Assuntos
Ansiedade/epidemiologia , Terremotos , Transtornos Psicofisiológicos/epidemiologia , Adolescente , Fatores Etários , Ansiedade/etiologia , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Transtornos Psicofisiológicos/etiologia , Fatores de Risco , Fatores Sexuais
8.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 30(6): 538-43, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26016364

RESUMO

OBJECTIVE: This study aimed to explore the scene-trait coping style of military rescuers in Wenchuan earthquake in an effort to provide scientific evidences for mental intervention program for Chinese military personnel. METHODS: By cluster sampling, a total of 151 military rescuers and 331 control servicemen were administered the military personnel scene-trait coping style scale (MPSTCSS). RESULTS: All active coping factor scores, and passive coping factor scores of affection, health and economy in the rescuer group were significantly higher than those in control group (P < 0.05). The 21-above age subgroup, the 3-year plus service subgroup, and the officer subgroup had significantly higher active coping factor scores on military tasks, military experience and personal development than those of the 21-below age subgroup, 3-year minus service subgroup and the soldier subgroup, respectively (P < 0.05 or P < 0.01). CONCLUSION: The earthquake relief servicemen can cope with stressful situations better than control group by taking active coping style. The officers, servicemen older than 21 years, and servicemen with more service duration than 3 years could usually take active coping style.


Assuntos
Adaptação Psicológica , Desastres , Terremotos , Militares/psicologia , Estresse Psicológico , Humanos
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