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1.
Hum Mol Genet ; 32(14): 2307-2317, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37070736

RESUMEN

Several different mutations in the proteome of centriole 1 centriolar protein B (POC1B) have been linked to cone dystrophy or cone-rod dystrophy (CORD). However, mutations in POC1B that are associated with both CORD and oligoasthenoteratozoospermia (OAT) have not been reported previously. Here, whole-exome sequencing was performed to identify a homozygous frameshift variant (c.151delG) in POC1B in the two brothers who had been diagnosed with both CORD and OAT from a consanguineous family. Transcript and protein analyses of biological samples from the two patients carrying the variant showed that POC1B protein is lost in sperm cells. The system CRISPR/Cas9 was utilized to create poc1bc.151delG/c.151delG knock-in (KI) mice. Notably, poc1bc.151delG/c.151delG KI male mice presented with OAT phenotype. Additionally, testicular histology and transmission electron microscopy analysis of the testes and sperm indicated that Poc1b mutation results in abnormal formation of acrosomes and flagella. Collectively, according to our experimental data on human volunteers and animal models, biallelic mutations in POC1B can cause OAT and CORD in mice and humans.


Asunto(s)
Astenozoospermia , Distrofias de Conos y Bastones , Infertilidad Masculina , Oligospermia , Humanos , Masculino , Animales , Ratones , Oligospermia/genética , Infertilidad Masculina/genética , Astenozoospermia/genética , Semen/metabolismo , Mutación , Proteínas de Ciclo Celular/genética
2.
Nat Mater ; 23(9): 1259-1267, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38769206

RESUMEN

Structurally ordered L10-PtM (M = Fe, Co, Ni and so on) intermetallic nanocrystals, benefiting from the chemically ordered structure and higher stability, are one of the best electrocatalysts used for fuel cells. However, their practical development is greatly plagued by the challenge that the high-temperature (>600 °C) annealing treatment necessary for realizing the ordered structure usually leads to severe particle sintering, morphology change and low ordering degree, which makes it very difficult for the gram-scale preparation of desirable PtM intermetallic nanocrystals with high Pt content for practical fuel cell applications. Here we report a new concept involving the low-melting-point-metal (M' = Sn, Ga, In)-induced bond strength weakening strategy to reduce Ea and promote the ordering process of PtM (M = Ni, Co, Fe, Cu and Zn) alloy catalysts for a higher ordering degree. We demonstrate that the introduction of M' can reduce the ordering temperature to extremely low temperatures (≤450 °C) and thus enable the preparation of high-Pt-content (≥40 wt%) L10-Pt-M-M' intermetallic nanocrystals as well as ten-gram-scale production. X-ray spectroscopy studies, in situ electron microscopy and theoretical calculations reveal the fundamental mechanism of the Sn-facilitated ordering process at low temperatures, which involves weakened bond strength and consequently reduced Ea via Sn doping, the formation and fast diffusion of low-coordinated surface free atoms, and subsequent L10 nucleation. The developed L10-Ga-PtNi/C catalysts display outstanding performance in H2-air fuel cells under both light- and heavy-duty vehicle conditions. Under the latter condition, the 40% L10-Pt50Ni35Ga15/C catalyst delivers a high current density of 1.67 A cm-2 at 0.7 V and retains 80% of the current density after extended 90,000 cycles, which exceeds the United States Department of Energy performance metrics and represents among the best cathodic electrocatalysts for practical proton-exchange membrane fuel cells.

3.
Reprod Biomed Online ; 47(2): 103214, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37277297

RESUMEN

RESEARCH QUESTION: What are the clinical outcomes and safety implications of early cumulus cell removal after short-term insemination combined with early rescue intracytoplasmic sperm injection (ICSI) in preventing fertilization failure? DESIGN: In this retrospective study, a total of 14,360 cycles were divided into four groups based on insemination method and fertilization ability: conventional IVF group (n = 5519); early cumulus cell removal group (n = 4107); conventional ICSI group (n = 4215); and early rescue ICSI group (where failed or low fertilization was predicted, n = 519). Fertilization outcomes, pregnancy outcomes, neonatal outcomes and birth defects were analysed by comparing the early cumulus cell removal group with the conventional IVF group, and the early rescue ICSI group with the conventional ICSI group. RESULTS: There were no significant differences in the outcomes of fertilization, pregnancy, neonates or birth defects between the conventional IVF group and the early cumulus cell removal group (P > 0.05). When compared with the conventional ICSI group, the early rescue ICSI group had similar rates of two pronuclei (2PN) at fertilization, clinical pregnancy, miscarriage, ectopic pregnancy, live birth, sex, mean gestational age, very low birthweight, macrosomia and birth defects (P > 0.05) but a higher polyploidy rate, lower high-quality embryo rate (both P < 0.001), lower twin pregnancy rate (P < 0.01), lower rate of low birthweight, and a higher rate of normal birthweight (both P = 0.024). CONCLUSIONS: Early cumulus cell removal combined with early rescue ICSI led to good pregnancy and neonatal outcomes without an increase in birth defects. This approach could therefore be an effective and safe method for patients with fertilization failure in conventional IVF.


Asunto(s)
Fertilización In Vitro , Inyecciones de Esperma Intracitoplasmáticas , Embarazo , Recién Nacido , Femenino , Humanos , Masculino , Inyecciones de Esperma Intracitoplasmáticas/métodos , Fertilización In Vitro/métodos , Estudios Retrospectivos , Células del Cúmulo , Peso al Nacer , Semen , Índice de Embarazo , Fertilización
4.
Reprod Biol Endocrinol ; 20(1): 43, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236366

RESUMEN

The heavy metal cadmium is proposed to be one of the environmental endocrine disruptors of spermatogenesis. Cadmium-induced inhibition of spermatogenesis is associated with a hormone secretion disorder. Letrozole is an aromatase inhibitor that increases peripheral androgen levels and stimulates spermatogenesis. However, the potential protective effects of letrozole on cadmium-induced reproductive toxicity remain to be elucidated. In this study, male mice were administered CdCl2 (4 mg/kg BW) orally by gavage alone or in combination with letrozole (0.25 mg/kg BW) for 30 days. Cd exposure caused a significant decreases in body weight, sperm count, motility, vitality, and plasma testosterone levels. Histopathological changes revealed extensive vacuolization and decreased spermatozoa in the lumen. However, in the Cd + letrozole group, letrozole treatment compensated for deficits in sperm parameters (count, motility, and vitality) induced by Cd. Letrozole treatment significantly increased serum testosterone levels, which were reduced by Cd. Histopathological studies revealed a systematic array of all germ cells, a preserved basement membrane and relatively less vacuolization. For a mechanistic examination, RNA-seq was used to profile alterations in gene expression in response to letrozole. Compared with that in the Cd-treated group, RNA-Seq analysis showed that 214 genes were differentially expressed in the presence of letrozole. Gene ontology (GO) enrichment analysis and KEGG signaling pathway analysis showed that steroid biosynthetic processes were the processes most affected by letrozole treatment. Furthermore, we found that the expression of the testosterone synthesis-related genes LHCGR (luteinizing hormone/choriogonadotropin receptor) and Hsd3b6 (3 beta- and steroid delta-isomerase 6) was significantly downregulated in Cd-treated testes, but these genes maintained similar expression levels in letrozole-treated testes as those in the control group. However, the transcription levels of inflammatory cytokines, such as IL-1ß and IL-6, and oxidative stress-related genes (Nrf2, Nqo1, and Ho-1) showed no changes. The present study suggests that the potential protective effect of letrozole on Cd-induced reproductive toxicity might be mediated by the upregulation of LHCGR and Hsd3b6, which would beneficially increase testosterone synthesis to achieve optimum protection of sperm quality and spermatogenesis.


Asunto(s)
Cadmio , Letrozol , Espermatogénesis , Testosterona , Animales , Masculino , Ratones , Cadmio/toxicidad , Citoprotección/efectos de los fármacos , Citoprotección/genética , Letrozol/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Redes y Vías Metabólicas/genética , Ratones Endogámicos ICR , Sustancias Protectoras/farmacología , Receptores de HL/efectos de los fármacos , Receptores de HL/genética , Receptores de HL/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Espermatogénesis/efectos de los fármacos , Espermatogénesis/genética , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Esteroide Isomerasas/efectos de los fármacos , Esteroide Isomerasas/genética , Esteroide Isomerasas/metabolismo , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/biosíntesis
5.
Opt Lett ; 46(19): 5008-5011, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34598254

RESUMEN

We propose and experimentally demonstrate a novel method for photonic-assisted microwave frequency measurement based on whispering-gallery mode (WGM) barcode, which is a dense spectrum generated by a micro-resonator that supports a large number of optical modes. The measurement relies on the relation between the microwave frequency and its unique barcode. The proposed system has the advantages of wide bandwidth, high accuracy, and multiple-frequency measurement capability. Microwave frequency measurement from 1 to 20 GHz is experimentally demonstrated with a measurement error of 40 kHz. For multi-tone signals, the frequency resolution is demonstrated to be less than 20 MHz. A dynamic multi-tone microwave signal consists of a 16-20 GHz linear frequency-modulated (LFM) signal, and a 10 GHz signal is measured to show the capability of multiple-frequency measurement. The system stability is also evaluated, and a self-reference method is proposed to maintain a long-term high-accuracy measurement.

6.
Opt Lett ; 46(6): 1241-1244, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33720157

RESUMEN

Compact speckle-based spectrometers that acquire lightwave wavelength from the speckle generated by turbid media are promising for high-resolution spectral analysis. For these devices, the reference establishment process is time consuming, and it is very difficult to obtain reference speckles covering a wide bandwidth with high resolution, which restricts the dynamic range in frequency (the ratio of bandwidth to resolution). In this Letter, we introduce optical frequency combs (OFCs) to the system to overcome these problems, which exist in the wavemeter based on Rayleigh speckle obtained from a single-mode fiber. In the experiment, the proposed wavemeter has a 1.5 nm bandwidth with 60 am resolution, covering a dynamic range in the frequency of 2×107, and a fast reference speckle establishment process that takes only 0.9 ms. The proposed method assisted by OFCs is a good prospect for a more practical speckle-based wavemeter with higher dynamic ranges.

7.
Reprod Biol Endocrinol ; 19(1): 92, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34154600

RESUMEN

BACKGROUND: The role of sexually transmitted infections (STIs) in semen parameters and male infertility is still a controversial area. Previous studies have found bacterial infection in a minority of infertile leukocytospermic males. This study aims to investigate the prevalence of STIs in semen from subfertile men with leukocytospermia (LCS) and without leukocytospermia (non-LCS) and their associations with sperm quality. METHODS: Semen samples were collected from 195 men who asked for a fertility evaluation. Infection with the above 6 pathogens was assessed in each sample. Sperm quality was compared in subfertile men with and without LCS. RESULTS: The LCS group had significantly decreased semen volume, sperm concentration, progressive motility, total motility and normal morphology. The infection rates of Ureaplasma urealyticum (Uuu), Ureaplasma parvum (Uup), Mycoplasma hominis (MH), Mycoplasma genitalium (MG), Chlamydia trachomatis (CT), herpes simplex virus-2 (HSV-2) and Neisseria gonorrhoeae (NG) were 8.7 %, 21.0 %, 8.2 %, 2.1 %, 3.6 %, 1.0 and 0 %, respectively. The STI detection rates of patients with LCS were higher than those of the non-LCS group (52.3 % vs. 39.3 %), although there was no statistically significant difference between the two groups (P = 0.07). All semen parameters were not significantly different between LCS with STIs and without STIs, except the semen volume in the MG-infected patients with LCS was significantly lower than that in the noninfected group. CONCLUSIONS: LCS was associated with a reduction in semen quality, but was not associated with STIs.


Asunto(s)
Infertilidad Masculina/microbiología , Leucocitos/microbiología , Análisis de Semen/métodos , Semen/microbiología , Enfermedades de Transmisión Sexual/microbiología , Adulto , Estudios de Cohortes , Estudios Transversales , Humanos , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/epidemiología , Leucocitos/fisiología , Masculino , Semen/fisiología , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiología
8.
J Am Chem Soc ; 142(9): 4508-4516, 2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32043354

RESUMEN

Two-dimensional (2D) covalent organic frameworks (COFs) are promising metal-free materials for photocatalytic water splitting because of their high surface area and predictability to assemble various molecules with tunable electronic properties. Unfortunately, 2D COFs capable of visible-light-driven photocatalytic overall water splitting are rare, partly due to rigorous requirements to their band alignments and coexistence of catalytic sites for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, 12 2D nitrogen-linked COFs are designed based on first-principles calculations and topological assembly of molecular segments with catalytic activities toward either HER or OER, respectively. The electronic band structures calculated with HSE06 method indicate that 2D COFs are semiconductors with a widely tunable bandgap ranging from 1.92 to 3.23 eV. The positions of both conduction and valence band edges of nine 2D COFs match well with the chemical reaction potential of H2/H+ and O2/H2O, which are capable of photocatalytic overall water splitting. Of particular importance is that three of them based on 2,4,6-tris(4-methylphenyl)-1,3,5-triazine (TST) can split water into hydrogen and oxygen under visible light. Our results agree with respect to the literature, with three of them having been studied for photocatalytic HER or CO2 reduction. In addition, we further experimentally demonstrate that I-TST presents both HER and OER activity under visible light. Our findings present a route to design practical 2D COFs as metal-free and single-material photocatalysts for overall water splitting under visible light.

9.
Opt Lett ; 45(4): 799-802, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32058473

RESUMEN

The characteristics of Rayleigh speckle generated from a single-mode fiber are related to the wavelength of the incident lightwave, which makes it possible to use Rayleigh speckle for spectrum measurement. Based on this feature, we propose, to the best of our knowledge, a novel wavemeter with high resolution realized using optical time domain reflectometry to obtain Rayleigh speckle. We show that the spectral resolution is inverse to the probe pulse width, with a spectral resolution of 6 fm corresponding to a 2 µs probe pulse. A correlation coefficient method is introduced to further increase the spectral resolution from 6 to 0.4 fm. Moreover, it is experimentally demonstrated that the system has the capability to resolve dynamic multi-wavelength signals with 25 µs time resolution. The proposed high-resolution wavemeter is a good prospect for cost effectiveness, compactness, and excellent performance of spectral resolution.

10.
Neurochem Res ; 45(10): 2302-2311, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32681444

RESUMEN

Spinal cord injury (SCI) is one of the diseases with high probability of causing disability in human beings, and there is no reliable treatment at present. Neuronal apoptosis is a vital component of secondary injury and plays a critical role in the development of neurological dysfunction after spinal cord injury. In this study, we found that the expression and distribution of HAX-1 in neurons increased 1 day after SCI. PC12 cells overexpressing HAX-1 showed decreased apoptosis and PC12 cells are more likely to undergo apoptosis after down-regulating HAX-1, which was confirmed via TUNEL experiments. We found GRP94 showed the same trend as HAX-1 in expression and interacted with HAX-1 and IRE-1 in both spinal cord tissue and PC12 cells, and this interaction seems to be enhanced after SCI. When the expression of HAX-1 was up-regulated, GRP94 also increased, but IRE-1 did not change at all. Further studies showed that overexpression of HAX-1 decreased the expression of pIRE-1, rather than IRE-1, and downstream proteins of the IRE signaling pathway (Caspase12, pJNK and CHOP) were significantly reduced, and vice versa. In animals treated with HAX-1 expressing adenovirus there are more neuronal cells remaining in the damaged spinal cord tissue, and hindlimb motor function of rats was significantly improved. So, we speculate that HAX-1 might play a role in protecting neurons from apoptosis after SCI by regulating the IRE-1 signaling pathway via promoting the dissociation of GRP94 from IRE-1. This may provide a theoretical basis and a potential therapeutic target for clinical improvement of neural function recovery after SCI.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Neuronas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Animales , Apoptosis/fisiología , Técnicas de Transferencia de Gen , Miembro Posterior/metabolismo , Péptidos y Proteínas de Señalización Intracelular/uso terapéutico , Masculino , Glicoproteínas de Membrana/metabolismo , Células PC12 , Ratas , Ratas Sprague-Dawley , Recuperación de la Función/fisiología , Transducción de Señal/fisiología , Traumatismos de la Médula Espinal/terapia
11.
Andrologia ; 52(9): e13663, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32478938

RESUMEN

Among causes of infertility, teratozoospermia is characterised by a percentage of morphologically abnormal spermatozoa >4%. Macrozoospermia, one form of monomorphic teratozoospermia, is observed in <1% of cases of male infertility and is described as approximately 100% large-headed and/or multitailed spermatozoa. This study reports that an infertile man with large-head spermatozoa presenting compound heterozygosity aurora kinase C (AURKC) mutations (c.382C>T, c.572C>T) by whole-exome sequencing. Consequently, both two novel AURKC mutations had high probability of damage-causing and conserved across species and extremely low allele frequency in the population. Flow cytometry analysis revealed a high ratio of sperm DNA fragmentation. Two intracytoplasmic sperm injection (ICSI) procedures were attempted for the patient, but all were unsuccessful. These results indicate that sequence analysis should be performed for the variants of AURKC in Chinese patients with macrozoospermia.


Asunto(s)
Infertilidad Masculina , Teratozoospermia , Aurora Quinasa C/genética , Humanos , Infertilidad Masculina/genética , Masculino , Mutación , Espermatozoides , Teratozoospermia/genética
12.
Angew Chem Int Ed Engl ; 59(6): 2318-2322, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-31750970

RESUMEN

Black phosphorus (BP) is a desirable anode material for alkali metal ion storage owing to its high electronic/ionic conductivity and theoretical capacity. In-depth understanding of the redox reactions between BP and the alkali metal ions is key to reveal the potential and limitations of BP, and thus to guide the design of BP-based composites for high-performance alkali metal ion batteries. Comparative studies of the electrochemical reactions of Li+ , Na+ , and K+ with BP were performed. Ex situ X-ray absorption near-edge spectroscopy combined with theoretical calculation reveal the lowest utilization of BP for K+ storage than for Na+ and Li+ , which is ascribed to the highest formation energy and the lowest ion diffusion coefficient of the final potassiation product K3 P, compared with Li3 P and Na3 P. As a result, restricting the formation of K3 P by limiting the discharge voltage achieves a gravimetric capacity of 1300 mAh g-1 which retains at 600 mAh g-1 after 50 cycles at 0.25 A g-1 .

13.
J Assist Reprod Genet ; 36(3): 529-534, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30594972

RESUMEN

PURPOSE: Macrozoospermia is a rare sperm morphologic abnormality associated with male infertility and is characterized by a high percentage of spermatozoa with large irregular heads. The aim of this study was to identify the genetic cause of an infertile male with macrozoospermia from a consanguineous family. METHODS: Whole-exome sequencing (WES) was performed using peripheral blood genomic DNA from the patient and his parents. RESULTS: WES analysis of the patient with macrozoospermia from a consanguineous family allowed the identification of a novel homozygous missense variant in the AURKC gene (c.269G>A). Bioinformatics analysis also suggested this variant a pathogenic mutation. Quantitative real-time PCR analysis showed that the mRNA level of AURKC is significantly decreased in the patient compared with his father. Moreover, no embryos were available for transfer after ICSI. CONCLUSIONS: These results further support the important role of AURKC in male infertility and guide the practitioner in optimal decision making for patients with macrozoospermia.


Asunto(s)
Aurora Quinasa C/genética , Infertilidad Masculina/genética , Teratozoospermia/genética , Adulto , Homocigoto , Humanos , Infertilidad Masculina/patología , Masculino , Mutación/genética , Linaje , Cabeza del Espermatozoide/patología , Espermatozoides/crecimiento & desarrollo , Espermatozoides/patología , Teratozoospermia/patología , Secuenciación del Exoma
14.
J Am Chem Soc ; 140(24): 7561-7567, 2018 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-29575904

RESUMEN

Exfoliated black phosphorus (BP), as a monolayer or few-layer material, has attracted tremendous attention owing to its unique physical properties for applications ranging from optoelectronics to photocatalytic hydrogen production. Approaching intrinsic properties has been, however, challenged by chemical reactions and structure degradation of BP under ambient conditions. Surface passivation by capping agents has been proposed to extend the processing time window, yet contamination or structure damage rise challenges for BP applications. Here, we report experiments combined with first-principle calculations that address the degradation chemistry of BP. Our results show that BP reacts with oxygen in water even without light illumination. The reaction follows a pseudo-first-order parallel reaction kinetics, produces PO23-, PO33-, and PO43- with reaction rate constants of 0.019, 0.034, and 0.023 per day, respectively, and occurs preferentially from the P atoms locating at BP edges, which yields structural decay from the nanoflake edges in water. In addition, a negligible decay ratio (0.9 ± 0.3 mol %) and preserved photocatalytic activity of BP are observed after storage in deoxygenated water for 15 days without surface passivation under ambient light. Our results reveal the chemistry of BP degradation and provide a practical approach for exfoliation, delivery, and application of BP.

16.
Am J Mens Health ; 18(4): 15579883241264120, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39054777

RESUMEN

Coronavirus disease 2019 (COVID-19) has been reported to decrease semen quality in reproductive-age men. Semen quality in vaccinated men after SARS-CoV-2 infection remains unclear. We recruited reproductive-age Chinese men scheduled for COVID-19 vaccination from December 2022 to March 2023. Among 1,639 vaccinated participants, an upward trend was found in sperm concentration (p < .001), progressive motility (p < .001), total motility (p < .001), total motile sperm count (TMSC) (p < .001), and normal morphology (p = .01) over time following COVID-19 recovery. Among men with an SARS-CoV-2 infection that lasted less than 30 days, men who received an inactivated vaccine booster had higher sperm progressive (p = .006) and total motility (p = .005) as well as TMSC (p = .008) than those without a booster vaccine, whereas no difference was found in semen parameters among men who received a recombinant protein vaccine. Similarly, an upward trend in semen quality was found among 122 men who provided semen samples before and after COVID-19. Higher risks of asthenozoospermia (odds ratio [OR] = 2.23, p < .001) and teratozoospermia (OR = 2.09, p = .03) were found among men who had an SARS-CoV-2 infection that lasted less than 30 days than among those without COVID-19. Collectively, after receiving SARS-CoV-2 vaccination, adverse but reversible semen parameters were observed in men recovering from COVID-19 over time. Recombinant protein vaccines and inactivated vaccine boosters should be recommended to all reproductive-age men.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Análisis de Semen , Humanos , Masculino , COVID-19/prevención & control , Estudios Retrospectivos , Adulto , Vacunas contra la COVID-19/administración & dosificación , SARS-CoV-2 , China , Recuento de Espermatozoides , Motilidad Espermática , Persona de Mediana Edad
17.
J Colloid Interface Sci ; 664: 588-595, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38490034

RESUMEN

Layered manganese-based cathode materials are considered as one of the promising cathodes benefit from inherent low manufacturing cost, non-toxic and high safety in aqueous zinc-ion batteries (AZIBs). However, the sluggish reaction kinetics within layered cathodes is inevitable due to the poor electrical/ionic conductivity. Herein, MnTiO3 is reported as a new cathode material for AZIBs and in-situ induced Mn-defect within MnTiO3 during the first charging is desirable to improve the reaction kinetics to a great extent. Additionally, DFT calculations further demonstrate that MnTiO3 with manganese defects exhibits a uniform charge distribution at the defect sites, enhancing the attraction towards H+ and Zn2+ ions. Furthermore, it performs good cycling stability which can obtain 115 mA h g-1 even at 400 mA g-1 after 450 cycles and the discharge capacity reaches up to 233.8 mAh/g at 100 mA g-1 when Mn-defect MnTiO3 was employed as the cathode. This research could provide a new method for the development and mechanism research of cathode materials for AZIBs.

18.
J Phys Chem Lett ; 15(4): 1070-1078, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38261575

RESUMEN

Two-dimensional (2D) metal borides (MBenes) with unique electronic structures and physicochemical properties hold great promise for various applications. Given the abundance of boron clusters, we proposed employing them as structural motifs to design 2D transition metal boron cluster compounds (MBnenes), an extension of MBenes. Herein, we have designed three stable MBnenes (M4(B12)2, M = Mn, Fe, Co) based on B12 clusters and investigated their electronic and magnetic properties using first-principles calculations. Mn4(B12)2 and Co4(B12)2 are semiconductors, while Fe4(B12)2 exhibits metallic behavior. The unique structure in MBnenes allows the coexistence of direct exchange interactions between adjacent metal atoms and indirect exchange interactions mediated by the clusters, endowing them with a Néel temperature (TN) up to 772 K. Moreover, both Mn4(B12)2 and Fe4(B12)2 showcase strain-independent room-temperature magnetism, making them potential candidates for spintronics applications. The MBnenes family provides a fresh avenue for the design of 2D materials featuring unique structures and excellent physicochemical properties.

19.
Asian J Androl ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162146

RESUMEN

A previous study showed that the length of the foreskin plays a role in the risk of sexually transmitted infections and chronic prostatitis, which can lead to poor quality of sexual life. Here, the association between foreskin length and sexual dysfunction was evaluated. A total of 5700 participants were recruited from the andrology clinic at The First Affiliated Hospital of University of Science and Technology of China (Hefei, China). Clinical characteristics, including foreskin length, were collected, and sexual function was assessed by the International Index of Erectile Function-5 (IIEF-5) and Premature Ejaculation Diagnostic Tool (PEDT) questionnaires. Men with sexual dysfunction were more likely to have redundant foreskin than men without sexual dysfunction. Among the 2721 erectile dysfunction (ED) patients and 1064 premature ejaculation (PE) patients, 301 (11.1%) ED patients and 135 (12.7%) PE patients had redundant foreskin, respectively. Men in the PE group were more likely to have redundant foreskin than men in the non-PE group (P = 0.004). Logistic regression analyses revealed that the presence of redundant foreskin was associated with increased odds of moderate/severe ED (adjusted odds ratio [aOR] = 1.31, adjusted P = 0.04), moderate PE (aOR = 1.38, adjusted P = 0.02), and probable PE (aOR = 1.37, adjusted P = 0.03) after adjusting for confounding variables. Our study revealed a positive correlation between the presence of redundant foreskin and the risk of sexual dysfunction, especially in PE patients. Assessment of the length of the foreskin during routine clinical diagnosis may provide information for patients with sexual dysfunction.

20.
Andrology ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39195011

RESUMEN

BACKGROUND: With the development of socio-economic conditions and a shift in attitudes towards fertility, there has been a gradual increase in delayed childbearing since the 2000s. Age plays a significant role in the decline of fertility. However, we know very little about the association of paternal age with reproductive outcomes. OBJECTIVES: To investigate the correlation between advanced paternal age and semen quality, embryo quality, pregnancy, and neonatal outcomes in IVF cycles. MATERIALS AND METHODS: In this study, after excluding female partners aged ≥35 years, we analyzed data from 761 infertile couples who underwent in vitro fertilization cycles at the First Affiliated Hospital of USTC between June 2020 and March 2023. Cases were classified into three groups according to the age of the male: <35 years (530 infertile couples), 35 years ≤ paternal age <40 years (125 infertile couples), and ≥40 years (106 infertile couples). Then, we compared the general clinical data arising from in vitro fertilization cycles between the three groups, including semen parameters, embryonic parameters, and pregnancy and neonatal birth outcomes. RESULTS: Data analysis showed that the duration of infertility and the incidence of secondary infertility were significantly higher in paternal age ≥35 years groups than those aged <35 years (all p < 0.05). We also observed a significant difference between ≥40 years and <35 years groups in terms of the normal fertilization rate, high-quality embryo rate, clinical pregnancy rate, miscarriage rate, live birth rate, Apgar scores, and the low birth weight neonatal rate (all p < 0.05). The group with paternal age ≥40 years showed statistically significant differences in terms of clinical pregnancy rate, miscarriage rate, live birth rate, and low birth weight on multivariable logistic regression (all p < 0.05). CONCLUSION: The results of our study indicate that advanced paternal age (≥40 years) has a significant impact on the embryo quality, pregnancy outcome, and neonatal outcome. Paternal age over 40 years is a risk for in vitro fertilization success rate.

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