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1.
Nanomaterials (Basel) ; 14(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38668160

RESUMO

Li-O2 batteries are considered a highly promising energy storage solution. However, their practical implementation is hindered by the sluggish kinetics of the oxygen reduction (ORR) and oxygen evolution (OER) reactions at cathodes during discharging and charging, respectively. In this work, we investigated the catalytic performance of Wn+1Cn and Wn+1CnO2 MXenes (n = 1, 2, and 3) as cathodes for Li-O2 batteries using first principles calculations. Both Wn+1Cn and Wn+1CnO2 MXenes show high conductivity, and their conductivity is further enhanced with increasing atomic layers, as reflected by the elevated density of states at the Fermi level. The oxygen functionalization can change the electronic properties of WC MXenes from the electrophilic W surface of Wn+1Cn to the nucleophilic O surface of Wn+1CnO2, which is beneficial for the activation of the Li-O bond, and thus promotes the Li+ deintercalation during the charge-discharge process. On both Wn+1Cn and Wn+1CnO2, the rate-determining step (RDS) of ORR is the formation of the (Li2O)2* product, while the RDS of OER is the LiO2* decomposition. The overpotentials of ORR and OER are positively linearly correlated with the adsorption energy of the RDS LixO2* intermediates. By lowering the energy band center, the oxygen functionalization and increasing atomic layers can effectively reduce the adsorption strength of the LixO2* intermediates, thereby reducing the ORR and OER overpotentials. The W4C3O2 MXene shows immense potential as a cathode catalyst for Li-O2 batteries due to its outstanding conductivity and super-low ORR, OER, and total overpotentials (0.25, 0.38, and 0.63 V).

2.
Asian J Androl ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38284776

RESUMO

The long-term safety and effectiveness of once-daily tadalafil is crucial, but limited data are available in Chinese patients with erectile dysfunction (ED). In this post-marketing, multicenter, randomized, open-label trial with 2-year follow-up, 635 ED cases were randomized to receive daily oral tadalafil 2.5 mg or 5 mg for 3 months, of whom 580 continued once-daily tadalafil 5 mg for 21 months. Treatment-emergent adverse events in the 12-month and 24-month period were similar, with the most common being viral upper respiratory tract infection, upper respiratory tract infection, and headache. Significant improvement from baseline in the International Index of Erectile Function-Erectile Function (IIEF-EF) score was detected at month 12 (least squares mean [LSM] change: 7.9, 95% confidence interval [CI]: 7.5-8.4, P < 0.001) and was maintained to month 24 (LSM change: 8.6, 95% CI: 8.1-9.0, P < 0.001). The proportions of patients regaining normal erectile function (IIEF-EF score ≥26) were 43.7% and 48.0% at months 12 and 24, respectively. Global Assessment Questionnaire results showed improved erection function in 97.5% of patients and improved ability to engage in sexual activity in 95.9% of patients at month 12; these values were 96.1% and 95.0% at month 24, respectively. The quality of sexual life score based on the Sexual Life Quality Questionnaire (SLQQ) was increased by 52.2% at month 12 and by 55.3% at month 24 (both P < 0.001). The treatment satisfaction score determined by SLQQ (mean ± standard deviation) was 62.4 ± 21.0 at month 12 versus 65.9 ± 20.2 at month 24. Two-year daily application of tadalafil 5 mg in Chinese men with ED showed a favorable safety profile and durable improvement in sexual performance and satisfaction.

4.
Basic Clin Androl ; 33(1): 28, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37558984

RESUMO

BACKGROUND: Testicular sperm aspiration (TESA) is widely used in the diagnosis and management of nonobstructive azoospermia. However, its ability for predicting microdissection testicular sperm extraction in nonobstructive azoospermia (NOA) patients with AZFc deletion remains uncertain. To investigate whether TESA affected the sperm retrieval rate (SRR) in NOA patients with AZFc deletion, a retrospective analysis of the clinical data of NOA patients with AZFc deletion who underwent microdissection testicular sperm extraction (micro-TESE) was conducted. The effects of age, testicular volume, follicle-stimulating hormone (FSH) levels, luteinizing hormone (LH) levels, testosterone (T) levels and TESA on the SRR were analyzed in this group of patients. RESULTS: A total of 181 individuals had their sperm successfully collected and underwent micro-TESE, with an SRR of 67.4%. The patients were separated into two groups based on their micro-TESE results (sperm acquisition and nonsperm acquisition), with no significant variations in age, testicular volume, FSH levels, LH levels, or T levels between the two groups. There was no significant difference in the SRR between any of the groups into which patients were classified based on reproductive hormone reference value ranges. Binary logistic regression was used to explore the absence of significant effects of age, testicular volume, FSH levels, LH levels, and T levels on sperm acquisition in patients undergoing micro-TESE. In the preoperative testicular diagnostic biopsy group, the sperm acquisition and nonsperm acquisition groups had SRRs of 90.1% and 65.1%, respectively. More significantly, there was no significant difference in the SRR between the negative preoperative testicular diagnostic biopsy group and the nonpreoperative testicular diagnostic biopsy group (65.1 vs. 63.8%, p = 0.855). CONCLUSION: There is a high probability of successful sperm acquisition in the testis of men undergoing micro-TESE. In this group of patients, age, testicular volume, FSH levels, LH levels, and T levels may have little bearing on the micro-TESE outcome. In patients whose preoperative TESA revealed the absence of sperm, the probability of obtaining sperm by micro-TESE remained high (65.1%); negative TESA results appeared to not influence the SRR (63.8%) in patients undergoing micro-TESE.


RéSUMé: CONTEXTE: L'aspiration testiculaire de spermatozoïdes (TESA) est largement utilisée dans le diagnostic et la prise en charge de l'azoospermie non obstructive. Cependant, sa capacité à prédire la présence de spermatozoïdes testiculaires lors de l'extraction par microdissection chez les patients atteints d'azoospermie non obstructive (NOA) et porteurs de la délétion AZFc reste incertaine. Pour déterminer si la TESA affectait le taux de récupération de spermatozoïdes (SRR) chez les patients atteints d'ANO avec délétion AZFc, nous avons mené une analyse rétrospective des données cliniques des patients atteints de NOA et d'une délétion AZFc ayant subi une extraction testiculaire de spermatozoïdes (micro-TESE) par microdissection. Les effets de l'âge, du volume testiculaire, des taux d'hormone folliculostimulante (FSH), d'hormone lutéinisante (LH), de testostérone (T) et de TESA sur le SRR ont été analysés chez ces patients. RéSULTATS: Au total, 181 personnes ont eu leur spermatozoïdes collectés avec succès par micro-TESE, avec un SRR de 67,4%. Les patients ont été répartis en 2 groupes en fonction de leurs résultats à la micro-TESE (obtention de spermatozoïdes et non obtention de spermatozoïdes), sans variations significatives de l'âge, du volume testiculaire, des taux de FSH, LH ou de T entre les 2 groupes. Aucune différence significative du SRR n'a été retrouvée entre les groupes dans lesquels les patients ont été classés en fonction des plages de valeurs de référence des hormones reproductives. La régression logistique binaire a été utilisée pour explorer l'absence d'effets significatifs de l'âge, du volume testiculaire, des taux de FSH, de LH et de T sur la récupération de spermatozoïdes chez les patients bénéficiant d'une micro-TESE. Dans le groupe de biopsie diagnostique testiculaire préopératoire, les groupes avec récupération de spermatozoïdes et sans récupération de spermatozoïdes avaient respectivement des SRR de 90,1% et 65,1%. Plus important encore, il n'y avait pas de différence significative du SRR entre le groupe de biopsie diagnostique testiculaire préopératoire négatif et le groupe sans biopsie diagnostique testiculaire préopératoire (65,1 vs 63,8%, p = 0,855). CONCLUSIONS: Il existe une forte probabilité de récupération réussie de spermatozoïdes testiculaires chez les hommes bénéficiant d'une micro-TESE. Dans ce groupe de patients, l'âge, le volume testiculaire, les taux de FSH, de LH et de T ont peu d'incidence sur le résultat de la micro-TESE. Chez les patients dont la TESA préopératoire a révélé l'absence de spermatozoïdes, la probabilité d'obtenir des spermatozoïdes par micro-TESE est restée élevée (65,1%); les résultats négatifs d'une TESA ne semblaient pas influencer le SRR (63,8%) chez les patients bénéficiant d'une micro-TESE.

5.
Nat Commun ; 14(1): 3767, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355646

RESUMO

Designing Pt-based electrocatalysts with high catalytic activity and CO tolerance is challenging but extremely desirable for alkaline hydrogen oxidation reaction. Herein we report the design of a series of single-atom lanthanide (La, Ce, Pr, Nd, and Lu)-embedded ultrasmall Pt nanoclusters for efficient alkaline hydrogen electro-oxidation catalysis based on vapor filling and spatially confined reduction/growth of metal species. Mechanism studies reveal that oxophilic single-atom lanthanide species in Pt nanoclusters can serve as the Lewis acid site for selective OH- adsorption and regulate the binding strength of intermediates on Pt sites, which promotes the kinetics of hydrogen oxidation and CO oxidation by accelerating the combination of OH- and *H/*CO in kinetics and thermodynamics, endowing the electrocatalyst with up to 14.3-times higher mass activity than commercial Pt/C and enhanced CO tolerance. This work may shed light on the design of metal nanocluster-based electrocatalysts for energy conversion.


Assuntos
Elementos da Série dos Lantanídeos , Metais Terras Raras , Platina , Oxirredução , Monóxido de Carbono , Hidrogênio
6.
Asian J Androl ; 25(6): 704-707, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005982

RESUMO

To investigate the factors affecting the sperm retrieval rate of microdissection testicular sperm extraction (micro-TESE) in patients with nonmosaic Klinefelter syndrome (KS), 64 patients with nonmosaic KS who underwent micro-TESE in the Center for Reproductive Medicine of Peking University Third Hospital (Beijing, China) between January 2016 and December 2017 were included in the study. Data on medical history, physical examination and laboratory examination results, and micro-TESE outcomes were collected. Patients were divided into two groups according to micro-TESE outcomes. The following factors were compared between the two groups by the Mann‒Whitney U test or Student's t-test based on the distribution (nonnormal or normal) of the factors: age, testicular size, follicle-stimulating hormone level, luteinizing hormone level, testosterone level, and anti-Müllerian hormone level. The overall success rate of sperm retrieval was 50.0%. Correlation analysis showed that testicular volume was positively correlated with testosterone level. Using a logistic regression model, age and anti-Müllerian hormone levels were found to be better predictors for the sperm retrieval rate than the other parameters.


Assuntos
Azoospermia , Síndrome de Klinefelter , Humanos , Masculino , Recuperação Espermática , Microdissecção , Hormônio Antimülleriano , Sêmen , Testículo , Espermatozoides , Testosterona , Estudos Retrospectivos
7.
ACS Appl Mater Interfaces ; 15(15): 19653-19664, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37015891

RESUMO

Well-dispersed PdIn bimetallic alloy nanoparticles (1-4 nm) were immobilized on mesostructured silica by an in situ capture-alloying strategy, and PdIn-In2O3 interfaces were rationally constructed by changing the In2O3 loading and reduction temperature. The catalytic performance for benzyl alcohol partial oxidation was evaluated, and a catalytic synergy was observed. The Pd-rich PdIn-In2O3 interface is prone to be formed on the catalyst with a low In2O3 loading after being reduced at 300 °C. It was demonstrated that the Pd-rich PdIn-In2O3 interface was more active for benzyl alcohol partial oxidation than In-rich Pd2In3 species, which was likely to be formed at a high reduction temperature (400 °C). The high catalytic activity on the Pd-rich PdIn-In2O3 interface was attributed to the exposure of more Pd-enriched active sites, and an optimized PdIn-In2O3/Pd assemble ratio enhanced the oxygen transfer during partial oxidation. The density functional theory (DFT) calculation confirmed that the Pd-rich Pd3In1(111)-In2O3 interface facilitated the activation of oxygen molecules, resulting in high catalytic activity.

8.
Transl Androl Urol ; 12(2): 187-196, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36915889

RESUMO

Background: Male reproductive health has become a serious public health concern, and semen quality is essential to male reproduction. We aimed to investigate geographical differences in the semen quality of sperm donors from northern and southern China by enrolling donors across the country. Methods: A total of 1,012 sperm donors were enrolled in this study between 2015 and 2019. Donors were first divided into two parts based on their birthplace according to the "Qinling-Huaihe" line, and secondly, by their residential latitude. Finally, donors were re-classified into two groups (typically north and south) which contained 667 samples. Results: Statistically significant differences in sperm concentration were observed among men from different latitudes in China (P=0.04). The sperm concentrations of males from 18° to 27° north latitude were significantly lower than those from 36° to 45° and 45° to 54° [median 131, 134, and 146, respectively, P=0.021 (18° to 27° vs. 36° to 45°) and P=0.01 (18° to 27° vs. 45° to 54°)]. Conclusion: We hypothesize environmental pollution and mental stress due to the increased population size may be the main factors underlying differences in the sperm quality of men in northern and southern China.

9.
Basic Clin Androl ; 33(1): 8, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36792987

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) outbreak has had a widespread and profound impact on people's mental health. The factors associated with mental symptoms among men diagnosed with infertility, a disease closely related to psychological conditions, remain unclear. The aim of this study is to investigate the risk factors associated with mental symptoms among infertile Chinese men during the pandemic. RESULTS: A total of 4,098 eligible participants were recruited in this cross-sectional, nationwide study, including 2,034 (49.6%) with primary infertility and 2,064 (50.4%) with secondary infertility. The prevalence of mental health conditions was 36.3%, 39.6%, and 6.7% for anxiety, depression, and post-pandemic stress, respectively. Sexual dysfunction is associated with a higher risk with adjusted odds ratios (ORs) of 1.40 for anxiety, 1.38 for depression, and 2.32 for stress. Men receiving infertility drug therapy displayed a higher risk for anxiety (adjusted OR, 1.31) and depression (adjusted OR, 1.28) symptoms, while those receiving intrauterine insemination had a lower risk of anxiety (adjusted OR, 0.56) and depression (adjusted OR, 0.55) symptoms. CONCLUSION: The COVID-19 pandemic has had a significant psychological impact on infertile men. Several psychologically vulnerable populations were identified, including individuals with sexual dysfunction, respondents receiving infertility drug therapy, and those experiencing control measures for COVID-19. The findings provide a comprehensive profile of the mental health status of infertile Chinese men during the COVID-19 outbreak and provide potential psychological intervention strategies.


RéSUMé: CONTEXTE: L'épidémie de maladie à coronavirus 2019 (COVID-19) a eu un impact étendu et profond sur la santé mentale des gens. Les facteurs associés aux symptômes mentaux chez les hommes diagnostiqués comme infertiles, une maladie étroitement liée aux conditions psychologiques, restent flous. L'objectif de cette étude est d'étudier les facteurs de risque associés aux symptômes mentaux chez les hommes chinois infertiles pendant la pandémie. RéSULTATS: Au total, 4 098 participants admissibles ont été recrutés dans cette étude transversale à l'échelle nationale, dont 2 034 (49,6%) présentaient une infertilité primaire et 2 064 (50,4%) une infertilité secondaire. La prévalence des problèmes de santé mentale était respectivement de 36,3 %, 39,6 % et 6,7 % pour l'anxiété, la dépression, et le stress postpandémique. La dysfonction sexuelle est associée à un risque plus élevé avec des odds ratios ajustés (OR) de 1,40 pour l'anxiété, 1,38 pour la dépression et 2,32 pour le stress. Les hommes recevant un traitement médicamenteux contre l'infertilité présentaient un risque plus élevé de symptômes d'anxiété (OR ajusté, 1,31) et de dépression (OR ajusté, 1,28), alors que ceux dont le traitement consistait à faire des inséminations intra-utérines présentaient un risque plus faible de symptômes d'anxiété (OR ajusté, 0,56) et de dépression (OR ajusté, 0,55). CONCLUSIONS: La pandémie de COVID-19 a eu un impact psychologique important sur les hommes infertiles. Plusieurs populations psychologiquement vulnérables ont été identifiées, notamment les personnes souffrant de dysfonction sexuelle, les hommes recevant un traitement médicamenteux contre l'infertilité, et ceux subissant des mesures de contrôle de la COVID-19. Les résultats fournissent un profil complet de l'état de santé mentale des hommes Chinois infertiles pendant l'épidémie de COVID-19 et fournissent des stratégies potentielles d'intervention psychologique.

10.
Asian J Androl ; 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36814170

RESUMO

Microdissection testicular sperm extraction (micro-TESE) is widely used to treat nonobstructive azoospermia. However, a good prediction model is required to anticipate a successful sperm retrieval rate before performing micro-TESE. This retrospective study analyzed the clinical records of 200 nonobstructive azoospermia patients between January 2021 and December 2021. The backward method was used to perform binary logistic regression analysis and identify factors that predicted a successful micro-TESE sperm retrieval. The prediction model was constructed using acquired regression coefficients, and its predictive performance was assessed using the receiver operating characteristic curve. In all, 67 patients (sperm retrieval rate: 33.5%) underwent successful micro-TESE. Follicle-stimulating hormone, anti-Müllerian hormone, and inhibin B levels varied significantly between patients who underwent successful and unsuccessful micro-TESE. Binary logistic regression analysis yielded the following six predictors: anti-Müllerian hormone (odds ratio [OR] = 0.902, 95% confidence interval [CI]: 0.821-0.990), inhibin B (OR = 1.012, 95% CI: 1.001-1.024), Klinefelter's syndrome (OR = 0.022, 95% CI: 0.002-0.243), Y chromosome microdeletion (OR = 0.050, 95% CI: 0.005-0.504), cryptorchidism with orchiopexy (OR = 0.085, 95% CI: 0.008-0.929), and idiopathic nonobstructive azoospermia (OR = 0.031, 95% CI: 0.003-0.277). The prediction model had an area under the curve of 0.720 (95% CI: 0.645-0.794), sensitivity of 65.7%, specificity of 72.2%, Youden index of 0.379, and cut-off value of 0.305 overall, indicating good predictive value and accuracy. This model can assist clinicians and nonobstructive azoospermia patients in decision-making and avoiding negative micro-TESE results.

11.
J Clin Med ; 12(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36675430

RESUMO

Background: The lack of clinically useful biomarkers for predicting micro-TESE outcomes in males with idiopathic NOA. To find clinically reliable serum reproductive hormone markers to predict the outcome of sperm retrieval in men with idiopathic NOA undergoing micro-TESE. Methods: We analyzed the clinical data of 168 men with idiopathic NOA treated with micro-TESE. The clinical predictors of a successful sperm retrieval were put to the test using logistic regression analysis. The clinical net benefit was calculated using a decision-curve analysis, and the predictive power of each variable was assessed using the ROC-derived area under the curve. Result: Between positive group and negative group for sperm retrieval, there was a statistically significant difference in INHB, AMH, and INHB/AMH. AMH, INHB, and INHB/AMH were each independent predictors of successful sperm retrieval, with INHB (OR1.02, p = 0.03), AMH (OR0.85, p = 0.01), INHB/AMH (OR1.08, p < 0.01). The ROC curve determined the optimal cut-off values for serum INHB and INHB/AMH in positive sperm retrieval patients undergoing micro-TESE. 21.51 pg/mL was the cut-off value for INHB. The cut-off value for INHB/AMH was 3.19, which had a 86.3% sensitivity and a 53.8% specificity. Using INHB and INHB/AMH prior to micro-TESE sperm retrieval in idiopathic NOA patients improved the net benefit of positive sperm retrieval, and the net benefit score of INHB/AMH was better than that of INHB, according to decision analysis curves. Conclusion: Serum INHB have predictive value for sperm retrieval outcomes in idiopathic NOA patients undergoing micro-TESE. Combining INHB and AMH, INHB/AMH seems to be a better predictor.

12.
Zygote ; 31(1): 25-30, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36205231

RESUMO

In the treatment of infertile patients with non-obstructive azoospermia (NOA) caused by the deletion of the azoospermia factor c region (AZFc) on the Y chromosome, synchronous and asynchronous surgical strategies are discussed. Clinical data from NOA patients with the AZFc deletion who underwent micro-TESE were analyzed retrospectively. The sperm retrieval rate (SRR) and sperm utilization rate of synchronous and asynchronous operation groups were followed up and compared. The fertilization rate, high-quality embryo rate, clinical pregnancy rate, abortion rate, and cumulative live birth rate of ICSI in patients with successful sperm retrieval were compared between the two groups. The two groups had sperm utilization rates of 98.9% (93/94) and 50.0% (14/28), respectively. The asynchronous group's sperm consumption rates were much lower than those of the synchronous operation group. Fertilization rate, high-quality embryo rate, clinical pregnancy rate of fresh transfer cycle, abortion rate, and cumulative live birth rate of patients in the synchronous operation group with fresh sperm, and the asynchronous operation group with thawed sperm, respectively, were 30.6% vs 33.8%, 33.8% vs 40.7%, 40.0% vs 12.5%, 30.4% vs 7.1%. Between the two groups, there was no significant difference. This suggests that individuals with NOA caused by the AZFc deletion have a high possibility of successfully acquiring sperm using micro-TESE and ICSI to conceive their own offspring. Synchronous micro-TESE is recommended to improve sperm utilization rate and the cumulative live birth rate.


Assuntos
Azoospermia , Gravidez , Feminino , Humanos , Masculino , Azoospermia/genética , Testículo , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas , Sêmen , Espermatozoides , Recuperação Espermática
13.
Phys Chem Chem Phys ; 24(47): 29141-29150, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36444744

RESUMO

Electrocatalytic water splitting suffers from sluggish kinetics towards the hydrogen evolution reaction (HER). Balancing the adsorption/desorption ability towards H* and OH* is considered to be an efficient way to enhance the HER efficiency, but it is too hard at one activity site. In this work, the HER activity of the single 3d transition metal atom-anchored BC2N monolayer (M@BC2N, M = Fe, Co, and Ni) was investigated by a density functional theory approach. Our calculation suggests that an efficient dual-active site is formed on M@BC2N towards the HER, i.e., the metal center M as the OH* active site and its adjacent C atoms as the H* active site. The combination of single M atoms with the BC2N monolayer can effectively tune the electronic structure of dual active sites to optimize the adsorption of H* and OH*, resulting in a HER activity sequence of Fe@BC2N < Co@BC2N < Ni@BC2N. Notably, the HER exchange current density of Ni@BC2N reaches up to 0.53 mA cm-2, which is close to the value for commercial Pt/C, suggesting its huge potential in the HER.

14.
Adv Sci (Weinh) ; 9(36): e2204949, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36285692

RESUMO

The development of low-cost, high-efficiency, and stable electrocatalysts for hydrogen evolution reaction (HER) under alkaline conditions is a key challenge in water electrolysis. Here, an interfacial engineering strategy that is capable of simultaneously regulating nanoscale structure, electronic structure, and interfacial structure of Mo2 N quantum dots decorated on conductive N-doped graphene via codoping single-atom Al and O (denoted as AlO@Mo2 N-NrGO) is reported. The conversion of Anderson polyoxometalates anion cluster ([AlMo6 O24 H6 ]3- , denoted as AlMo6) to Mo2 N quantum dots not only result in the generation of more exposed active sites but also in situ codoping atomically dispersed Al and O, that can fine-tune the electronic structure of Mo2 N. It is also identified that the surface reconstruction of AlOH hydrates in AlO@Mo2 N quantum dots plays an essential role in enhancing hydrophilicity and lowering the energy barriers for water dissociation and hydrogen desorption, resulting in a remarkable alkaline HER performance, even better than the commercial 20% Pt/C. Moreover, the strong interfacial interaction (MoN bonds) between AlO@Mo2 N and N-doped graphene can significantly improve electron transfer efficiency and interfacial stability. As a result, outstanding stability over 300 h at a current density higher than 100 mA cm-2 is achieved, demonstrating great potential for the practical application of this catalyst.

15.
ACS Appl Mater Interfaces ; 14(27): 30927-30936, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35776526

RESUMO

Rechargeable aluminum-ion batteries (RAIBs) are highly sought after due to the extremely high resource reserves and theoretical capacity (2980 mA h/g) of metal aluminum. However, the lack of ideal cathode materials restricts its practical advancement. Here, we report a conductive polymer, polyphenylene, which is produced by the polymerization of molecular benzene as a cathode material for RAIBs with an excellent electrochemical performance. In electrochemical redox, polyphenylene is oxidized and loses electrons to form radical cations [C6H4]3n+ and intercalates with [AlCl4]- anion to achieve electrical neutrality and realize electrochemical energy storage. The stable structure of polyphenylene makes its discharge specific capacity reach 92 mA h/g at 100 mA/g; the discharge plateau is about 1.4 V and exhibits an excellent rate performance and long cycle stability. Under the super high current density of 10 A/g (∼85 C), the charging can be completed in 25 s, and the capacities have almost no decay after 30,000 cycles. Aluminum polyphenylene batteries have the potential to be used as low-cost, easy-to-process, lightweight, and high-capacity superfast rechargeable batteries for large-scale stationary power storage.

16.
Nat Commun ; 13(1): 1596, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35332161

RESUMO

The discord between the insufficient abundance and the excellent electrocatalytic activity of Pt urgently requires its atomic-level engineering for minimal Pt dosage yet maximized electrocatalytic performance. Here we report the design of ultrasmall triphenylphosphine-stabilized Pt6 nanoclusters for electrocatalytic hydrogen oxidation reaction in alkaline solution. Benefiting from the self-optimized ligand effect and atomic-precision structure, the nanocluster electrocatalyst demonstrates a high mass activity, a high stability, and outperforms both Pt single atoms and Pt nanoparticle analogues, uncovering an unexpected size optimization principle for designing Pt electrocatalysts. Moreover, the nanocluster electrocatalyst delivers a high CO-tolerant ability that conventional Pt/C catalyst lacks. Theoretical calculations confirm that the enhanced electrocatalytic performance is attributable to the bifold effects of the triphenylphosphine ligand, which can not only tune the formation of atomically precise platinum nanoclusters, but also shift the d-band center of Pt atoms for favorable adsorption kinetics of *H, *OH, and CO.

17.
Asian J Androl ; 24(6): 660-665, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35229760

RESUMO

Circular RNAs (circRNAs) are highly conserved and ubiquitously expressed noncoding RNAs that participate in multiple reproduction-related diseases. However, the expression pattern and potential functions of circRNAs in the testes of patients with non-obstructive azoospermia (NOA) remain elusive. In this study, according to a circRNA array, a total of 37 881 circRNAs were identified that were differentially expressed in the testes of NOA patients compared with normal controls, including 19 874 upregulated circRNAs and 18 007 downregulated circRNAs. Using quantitative real-time polymerase chain reaction (qRT-PCR) analysis, we confirmed that the change tendency of some specific circRNAs, including hsa_circ_0137890, hsa_circ_0136298, and hsa_circ_0007273, was consistent with the microarray data in another larger sample. The structures and characteristics of these circRNAs were confirmed by Sanger sequencing, and fluorescence in situ hybridization revealed that these circRNAs were primarily expressed in the cytoplasm. Bioinformatics analysis was used to construct the competing endogenous RNA (ceRNA) network, and numerous miRNAs that could be paired with circRNAs validated in this study were reported to be vital for spermatogenesis regulation. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses indicated that genes involved in axoneme assembly, microtubule-based processes, and cell proliferation were significantly enriched. Our data suggest that there are aberrantly expressed circRNA profiles in patients with NOA and that these circRNAs may help identify key diagnostic and therapeutic molecular biomarkers for NOA patients.


Assuntos
Azoospermia , MicroRNAs , Masculino , Humanos , RNA Circular/genética , Azoospermia/genética , Hibridização in Situ Fluorescente , MicroRNAs/genética , MicroRNAs/metabolismo
18.
Angew Chem Int Ed Engl ; 61(3): e202114681, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34755421

RESUMO

As an emerging post-lithium battery technology, aluminum ion batteries (AIBs) have the advantages of large Al reserves and high safety, and have great potential to be applied to power grid energy storage. But current graphite cathode materials are limited in charge storage capacity due to the formation of stage-4 graphite-intercalated compounds (GICs) in the fully charged state. Herein, we propose a new type of cathode materials for AIBs, namely polycyclic aromatic hydrocarbons (PAHs), which resemble graphite in terms of the large conjugated π bond, but do not form GICs in the charge process. Quantum chemistry calculations show that PAHs can bind AlCl4 - through the interaction between the conjugated π bond in the PAHs and AlCl4 - , forming on-plane interactions. The theoretical specific capacity of PAHs is negatively correlated with the number of benzene rings in the PAHs. Then, under the guidance of theoretical calculations, anthracene, a three-ring PAH, was evaluated as a cathode material for AIBs. Electrochemical measurements show that anthracene has a high specific capacity of 157 mAh g-1 (at 100 mA g-1 ) and still maintains a specific capacity of 130 mAh g-1 after 800 cycles. This work provides a feasible "theory guides practice" research model for the development of energy storage materials, and also provides a new class of promising cathode materials for AIBs.

19.
ACS Appl Mater Interfaces ; 13(42): 49780-49792, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637263

RESUMO

A balance between catalytic activity and product selectivity remains a dilemma for the partial oxidation processes because the products are prone to be overoxidized. In this work, we report on the partial oxidation of benzyl alcohol using a modified catalyst consisting of nanosized Au-Pd particles (NPs) with tin oxide (SnOx) deposited on a mesoporous silica support. We found that the SnOx promotes the autogenous reduction of PdO to active Pd0 species on the Au-Pd NP catalyst (SnOx@AP-ox) before H2 reduction, which is due to the high oxophilicity of Sn. The presence of active Pd0 species and the enhancement of oxygen transfer by SnOx led to high catalytic activity. The benzaldehyde selectivity was enhanced with the increase of SnOx content on catalyst SnOx@AP-ox, which is ascribed to the modulated affinity of reactants and products on the catalyst surface through the redox switching of Sn species. After H2 reduction, SnOx was partially reduced and Au-Pd-Sn alloy was formed. The formation of Au-Pd-Sn alloy weakened both the catalytic synergy of Au-Pd alloy NPs and the adsorption of benzyl alcohol on the reduced catalyst, thus leading to low catalytic activity.

20.
Asian J Androl ; 23(2): 211-214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32719193

RESUMO

We performed this study to evaluate the clinical outcomes of microdissection testicular sperm extraction-intracytoplasmic sperm injection (micro-TESE-ICSI) treatment that used fresh or cryopreserved sperm in patients with nonobstructive azoospermia (NOA). A total of 338 NOA patients with 344 consecutive cycles received treatment in the reproductive medicine center of Peking University Third Hospital in Beijing, China, from January 2014 to December 2017. Fresh oocytes and fresh sperm were used in 222 patients with 234 cycles (Group A). Fresh oocytes and cryopreserved sperm were used in 116 patients with 110 cycles (Group B). We compared patient characteristics, embryonic development, and pregnancy outcomes between Groups A and B. There was no statistical difference in the patient characteristics, and no differences were observed with fertilization or quality embryo rates between Groups A and B. The rates of clinical pregnancy and live birth were both higher for Group A than those for Group B (both P < 0.05). In conclusion, fresh testicular sperm appears to produce better ICSI outcomes than cryopreserved testicular sperm in patients with NOA.


Assuntos
Azoospermia/terapia , Criopreservação , Preservação do Sêmen , Injeções de Esperma Intracitoplásmicas/métodos , Recuperação Espermática , Adulto , Implantação do Embrião , Transferência Embrionária , Embrião de Mamíferos , Feminino , Humanos , Masculino , Microdissecção , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Testículo , Resultado do Tratamento , Adulto Jovem
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