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1.
Angew Chem Int Ed Engl ; : e202412080, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39234632

RESUMEN

Proton exchange membrane (PEM) electrolysis holds great promise for green hydrogen production, but suffering from high loading of platinum-group metals (PGM) for large-scale deployment. Anchoring PGM-based materials on supports can not only improve the atomic utilization of active sites but also enhance the intrinsic activity. However, in practical PEM electrolysis, it is still challenging to mediate hydrogen adsorption/desorption pathways with high coverage of hydrogen intermediates over catalyst surface. Here, operando generated stable palladium (Pd) hydride nanoclusters anchored on tungsten carbide (WCx) supports were constructed for hydrogen evolution in PEM electrolysis. Under PEM operando conditions, hydrogen intercalation induces formation of Pd hydrides (PdHx) featuring weakened hydrogen binding energy (HBE), thus triggering reverse hydrogen spillover from WCx (strong HBE) supports to PdHx sites, which have been evidenced by operando characterizations, electrochemical results and theoretical studies. This PdHx-WCx material can be directly utilized as cathode electrocatalysts in PEM electrolysis with ultralow Pd loading of 0.022 mg cm-2, delivering the current density of 1 A cm-2 at the cell voltage of ~1.66 V and continuously running for 200 hours without obvious degradation. This innovative strategy via tuning the operando characteristics to mediate reverse hydrogen spillover provide new insights for designing high-performance supported PGM-based electrocatalysts.

2.
Placenta ; 155: 78-87, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39154487

RESUMEN

INTRODUCTION: An early evaluating system for autism spectrum disorder (ASD) severity is crucial. Questionnaire survey is challenging for accurately assessing the severity levels for ASD in children. METHODS: Offspring with ASD-like phenotypes were induced by treating pregnant mice with Poly (I:C) at GD12.5 and the placentae corresponding to the offspring were obtained by caesarean. The autism severity composite score (ASCS) for offspring was calculated through behavioral tests. HE staining and immunohistochemistry were used to observe the morphology of placenta. Candidate biomarkers were identified by weighted protein co-expression network analysis (WPCNA) combined with machine learning and further validated by ELISA. Sperman's was used to analyze the correlation between biomarkers and metabolome. RESULTS: The placental weight and mean vascular area of male offspring with ASD-like phenotypes were significantly decreased compared with typical mice. According to the WPCNA, four modules were identified and significantly correlated with ASCS of offspring. Two biomarkers (ASPG and DAD1) with high correlation with ASCS in offspring were identified. DISCUSSION: VEGF pathway may contribute to sexual dimorphism in placental morphology within mice with ASD-like phenotypes in term. The placental ASPG and DAD1 levels could reflect ASD-like symptom severity levels in male/female mice offspring.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Asparaginasa , Trastorno del Espectro Autista , Proteínas de la Membrana , Placenta , Animales , Femenino , Masculino , Ratones , Embarazo , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Trastorno del Espectro Autista/metabolismo , Biomarcadores/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Placenta/metabolismo , Placenta/patología , Índice de Severidad de la Enfermedad , Asparaginasa/genética , Asparaginasa/metabolismo
3.
World J Clin Cases ; 9(17): 4188-4198, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34141781

RESUMEN

BACKGROUND: Cervical cancer is the fourth commonest malignancy in women around the world. It represents the second most commonly diagnosed cancer in South East Asian women, and an important cancer death cause in women of developing nations. Data collected in 2018 revealed 5690000 cervical cancer cases worldwide, 85% of which occurred in developing countries. AIM: To assess self-perceived burden (SPB) and related influencing factors in cervical cancer patients undergoing radiotherapy. METHODS: Patients were prospectively included by convenient sampling at The Fifth Affiliated Hospital of Sun Yat-Sen University, China between March 2018 and March 2019. The survey was completed using a self-designed general information questionnaire, the SPB scale for cancer patients, and the self-care self-efficacy scale, Strategies Used by People to Promote Health, which were delivered to patients with cervical cancer undergoing radiotherapy. Measurement data are expressed as the mean ± SD. Enumeration data are expressed as frequencies or percentages. Caregivers were the spouse, offspring, and other in 46.4, 40.9, and 12.7%, respectively, and the majority were male (59.1%). As for pathological type, 90 and 20 cases had squamous and adenocarcinoma/adenosquamous carcinomas, respectively. Stage IV disease was found in 12 (10.9%) patients. RESULTS: A total of 115 questionnaires were released, and five patients were excluded for too long evaluation time (n = 2) and the inability to confirm the questionnaire contents (n = 3). Finally, a total of 110 questionnaires were collected. They were aged 31-79 years, with the 40-59 age group being most represented (65.4% of all cases). Most patients were married (91.8%) and an overwhelming number had no religion (92.7%). Total SPB score was 43.13 ± 16.65. SPB was associated with the place of residence, monthly family income, payment method, transfer status, the presence of radiotherapy complications, and the presence of pain (P < 0.05). The SPB and self-care self-efficacy were negatively correlated (P < 0.01). In multivariate analysis, self-care self-efficacy, place of residence, monthly family income, payment method, degree of radiation dermatitis, and radiation proctitis were influencing factors of SPB (P < 0.05). CONCLUSION: Patients with cervical cancer undergoing radiotherapy often have SPB. Self-care self-efficacy scale, place of residence, monthly family income, payment method, and radiation dermatitis and proctitis are factors independently influencing SPB.

4.
Huan Jing Ke Xue ; 36(1): 215-20, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25898667

RESUMEN

The experiments were conducted to investigate the adsorption behavior of tetracycline on a kind of nano-sized amorphous carbon, which was synthetized in a molten salt electrochemical system, comprising a eutectic mixture of Li-Na-K carbonates. The results showed that, the carbon powder had a good adsorption performance. At 298K, the maximum adsorption capacity of tetracycline was 127.76 mg x g(-1). The adsorption data could be well fitted by the pseudo-second-order model and the Freundlich isotherm. Also, the thermodynamic tests for the adsorption were conducted. The adsorption was endothermic and spontaneous reaction with chemical bond as the dominant. The adsorption was pH dependent. The adsorption capacity reached the maximum when solution pH was 4 in the range from 2 to 11. The existence of cations had little effects on the adsorption. The adsorption capacity increased with the concentration of cations to a certain extent. Ion exchange may be one of the adsorption mechanisms, as well as, electric attraction and hydrogen bond. Moreover, desorption experiments were carried out in 0.25 mol x L(-1) CaCl2 or NaCl solution respectively. Desorption efficiency ranged from 7.42% to 25%, which was at a relatively low level. The result indicated that the chemical adsorption process was strong.


Asunto(s)
Carbono/química , Nanopartículas/química , Tetraciclina/química , Adsorción , Carbonatos , Intercambio Iónico , Termodinámica , Contaminantes Químicos del Agua
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