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1.
J Colloid Interface Sci ; 672: 12-20, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38824684

RESUMEN

Photoelectrochemical (PEC) water splitting on semiconductor electrodes is considered to be one of the important ways to produce clean and sustainable hydrogen fuel, which is a great help in solving energy and environmental problems. Bismuth vanadate (BiVO4) as a promising photoanode for photoelectrochemical water splitting still suffers from poor charge separation efficiency and photo-induced self-corrosion. Herein, we develop heterojunction-rich photoanodes composed of BiVO4 and iron vanadate (FeVO4), coated with nickel iron oxide (NiFeOx/FeVO4/BiVO4). The formation of the interface between BiVO4 and FeVO4 (Bi-VO4-Fe bridges) enhances the interfacial interaction, resulting in improved performance. Meanwhile, high-conductivity FeVO4 and NiFeOx oxygen evolution co-catalysts effectively enhance bulk electron/hole separation, interface water's kinetics and photostability. Concurrently, the optimized NiFeOx/FeVO4/BiVO4 possesses a remarkable photocurrent density of 5.59 mA/cm2 at 1.23 V versus reversible hydrogen electrode (vs RHE) under AM 1.5G (Air Mass 1.5 Global) simulated sunlight, accompanied by superior stability without any decreased of its photocurrent density after 14 h. This work not only reveals the crucial role of built-in electric field in BiVO4-based photoanode during PEC water splitting, but also provides a new guide to the design of efficient photoanode for PEC.

2.
J Appl Toxicol ; 44(8): 1257-1268, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38700028

RESUMEN

This study demonstrated that both copper oxide nanoparticles (CuO-NPs) and copper nanoparticles (Cu-NPs) can cause swelling, inflammation, and cause damage to the mitochondria of alveolar type II epithelial cells in mice. Cellular examinations indicated that both CuO-NPs and Cu-NPs can reduce cell viability and harm the mitochondria of human bronchial epithelial cells, particularly Beas-2B cells. However, it is clear that CuO-NPs exhibit a more pronounced detrimental effect compared with Cu-NPs. Using bafilomycin A1 (Bafi A1), an inhibitor of lysosomal acidification, was found to enhance cell viability and alleviate mitochondrial damage caused by CuO-NPs. Additionally, Bafi A1 also reduces the accumulation of dihydrolipoamide S-acetyltransferase (DLAT), a marker for mitochondrial protein toxicity, induced by CuO-NPs. This observation suggests that the toxicity of CuO-NPs depends on the distribution of copper particles within cells, a process facilitated by the acidic environment of lysosomes. The release of copper ions is thought to be triggered by the acidic conditions within lysosomes, which aligns with the lysosomal Trojan horse mechanism. However, this association does not seem to be evident with Cu-NPs.


Asunto(s)
Supervivencia Celular , Cobre , Lisosomas , Macrólidos , Nanopartículas del Metal , Mitocondrias , Cobre/toxicidad , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Animales , Humanos , Nanopartículas del Metal/toxicidad , Macrólidos/toxicidad , Ratones , Supervivencia Celular/efectos de los fármacos , Línea Celular , Masculino
3.
Small ; : e2402406, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716755

RESUMEN

Bismuth vanadate (BiVO4), as a promising photoanode for photoelectrochemical (PEC) water splitting, suffers from poor charge separation efficiency and light absorption efficiency. Herein, iron oxychloride (FeOCl) is introduced as a novel cocatalyst simply grafted on BiVO4 to construct an integrated photoanode, enhancing PEC performance. The optimized FeOCl/BiVO4 photoanode exhibits a superior photocurrent density value of 5.23 mA cm-2 at 1.23 V versus reversible hydrogen electrode (RHE) under AM 1.5G illuminations. From experimental analysis, such high PEC performance is ascribed to the unique properties of FeOCl, facilitating charge transport, increasing light absorption efficiency, and promoting water oxidation kinetics. Density functional theory calculations further confirm that FeOCl optimizes the Gibbs free energy of H and O-containing intermediates (OOH*) during PEC processes, boosting the catalytic kinetics of PEC water splitting. This work presents FeOCl as a promising catalyst for constructing high efficient PEC water-splitting photoanodes.

4.
Small ; 20(31): e2311773, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38446094

RESUMEN

Active sites, mass loading, and Li-ion diffusion coefficient are the benchmarks for boosting the areal capacity and storage capability of electrode materials for lithium-ion batteries. However, simultaneously modulating these criteria to achieve high areal capacity in LIBs remains challenging. Herein, MoS2 is considered as a suitable electroactive host material for reversible Li-ion storage and establish an endogenous multi-heterojunction strategy with interfacial Mo-C/N-Mo-S coordination bonding that enables the concurrent regulation of these benchmarks. This strategy involves architecting 3D integrated conductive nanostructured frameworks composed of Mo2C-MoN@MoS2 on carbon cloth (denoted as C/MMMS) and refining the sluggish kinetics in the MoS2-based anodes. Benefiting from the rich hetero-interface active sites, optimized Li adsorption energy, and low diffusion barrier, C/MMMS reaches a mass loading of 12.11 mg cm-2 and showcases high areal capacity and remarkable rate capability of 9.6 mAh cm-2@0.4 mA cm-2 and 2.7 mAh cm-2@6.0 mA cm-2, respectively, alongside excellent stability after 500 electrochemical cycles. Moreover, this work not only affirms the outstanding performance of the optimized C/MMMS as an anode material for supercapacitors, underscoring its bifunctionality but also offers valuable insight into developing endogenous transition metal compound electrodes with high mass loading for the next-generation high areal capacity energy storage devices.

5.
Nanoscale ; 16(8): 4325-4332, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38357773

RESUMEN

Nickel nitride (Ni3N) is a promising electrocatalyst for the hydrogen evolution reaction (HER) owing to its excellent metallic features and has been demonstrated to exhibit considerable activity for water oxidation. However, its undesirable characteristics as an HER electrocatalyst due to its poor unfavourable d-band energy level significantly limit its water dissociation kinetics. Herein, the HER electrocatalytic activity of Ni3N was prominently enhanced via the simultaneous incorporation of bi-cations (vanadium (V) and iron (Fe), denoted as V-Fe-Ni3N). The optimized V-Fe-Ni3N displays impressive performance with an overpotential of 69 mV at 10 mA cm-2 and good stability in 1.0 M KOH, which is remarkably better than pristine Ni3N, V-doped Ni3N, and Fe-doped Ni3N and considerably closer to a commercial Pt/C catalyst. Based on density functional theory (DFT) studies, V and Fe atoms not only serve as active sites for promoting water dissociation kinetics but also tune the electronic structure of Ni3N to achieve optimized hydrogen adsorption capabilities. This work presents an inclusive understanding of the rational designing of high-performance transition metal nitride-based electrocatalysts for hydrogen production. Its electrocatalytic performance can be significantly enhanced by doping transition metal cations.

6.
JCI Insight ; 8(18)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37607000

RESUMEN

Uterine leiomyomas cause heavy menstrual bleeding, anemia, and pregnancy loss in millions of women worldwide. Driver mutations in the transcriptional mediator complex subunit 12 (MED12) gene in uterine myometrial cells initiate 70% of leiomyomas that grow in a progesterone-dependent manner. We showed a distinct chromatin occupancy landscape of MED12 in mutant MED12 (mut-MED12) versus WT-MED12 leiomyomas. Integration of cistromic and transcriptomics data identified tryptophan 2,3-dioxygenase (TDO2) as the top mut-MED12 target gene that was significantly upregulated in mut-MED12 leiomyomas when compared with adjacent myometrium and WT-MED12 leiomyomas. TDO2 catalyzes the conversion of tryptophan to kynurenine, an aryl hydrocarbon receptor (AHR) ligand that we confirmed to be significantly elevated in mut-MED12 leiomyomas. Treatment of primary mut-MED12 leiomyoma cells with tryptophan or kynurenine stimulated AHR nuclear translocation, increased proliferation, inhibited apoptosis, and induced AHR-target gene expression, whereas blocking the TDO2/kynurenine/AHR pathway by siRNA or pharmacological treatment abolished these effects. Progesterone receptors regulated the expression of AHR and its target genes. In vivo, TDO2 expression positively correlated with the expression of genes crucial for leiomyoma growth. In summary, activation of the TDO2/kynurenine/AHR pathway selectively in mut-MED12 leiomyomas promoted tumor growth and may inform the future development of targeted treatments and precision medicine.


Asunto(s)
Leiomioma , Neoplasias Uterinas , Femenino , Humanos , Triptófano , Quinurenina/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología , Triptófano Oxigenasa/genética , Triptófano Oxigenasa/metabolismo , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Leiomioma/genética , Leiomioma/metabolismo , Leiomioma/patología , Mutación , Complejo Mediador/genética , Complejo Mediador/metabolismo
7.
medRxiv ; 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37503225

RESUMEN

Perinatal depression (PND) is one of the most common medical complications during pregnancy and postpartum period, affecting 10-20% of pregnant individuals. Black and Latina women have higher rates of PND, yet they are less likely to be diagnosed and receive treatment. Machine learning (ML) models based on Electronic Medical Records (EMRs) have been effective in predicting postpartum depression in middle-class White women but have rarely included sufficient proportions of racial and ethnic minorities, which contributed to biases in ML models for minority women. Our goal is to determine whether ML models could serve to predict depression in early pregnancy in racial/ethnic minority women by leveraging EMR data. We extracted EMRs from a hospital in a large urban city that mostly served low-income Black and Hispanic women (N=5,875) in the U.S. Depressive symptom severity was assessed from a self-reported questionnaire, PHQ-9. We investigated multiple ML classifiers, used Shapley Additive Explanations (SHAP) for model interpretation, and determined model prediction bias with two metrics, Disparate Impact, and Equal Opportunity Difference. While ML model (Elastic Net) performance was low (ROCAUC=0.67), we identified well-known factors associated with PND, such as unplanned pregnancy and being single, as well as underexplored factors, such as self-report pain levels, lower levels of prenatal vitamin supplement intake, asthma, carrying a male fetus, and lower platelet levels blood. Our findings showed that despite being based on a sample mostly composed of 75% low-income minority women (54% Black and 27% Latina), the model performance was lower for these communities. In conclusion, ML models based on EMRs could moderately predict depression in early pregnancy, but their performance is biased against low-income minority women.

8.
Clin Transl Gastroenterol ; 14(7): e00597, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37162146

RESUMEN

INTRODUCTION: Diet and decreased gut microbiome diversity has been associated with acute pancreatitis (AP) risk. However, differences in dietary intake, gut microbiome, and their impact on microbial end metabolites have not been studied in AP. We aimed to determine differences in (i) dietary intake (ii) gut microbiome diversity and sulfidogenic bacterial abundance, and (iii) serum short-chain fatty acid (SCFA) and hydrogen sulfide (H 2 S) concentrations in AP and control subjects. METHODS: This case-control study recruited 54 AP and 46 control subjects during hospitalization. Clinical and diet data and stool and blood samples were collected. 16S rDNA sequencing was used to determine gut microbiome alpha diversity and composition. Serum SCFA and H 2 S levels were measured. Machine learning (ML) model was used to identify microbial targets associated with AP. RESULTS: AP patients had a decreased intake of vitamin D 3 , whole grains, fish, and beneficial eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids. AP patients also had lower gut microbiome diversity ( P = 0.021) and a higher abundance of sulfidogenic bacteria including Veillonella sp. and Haemophilus sp., which were associated with AP risk. Serum acetate and H 2 S concentrations were significantly higher in the AP group ( P < 0.001 and P = 0.043, respectively). ML model had 96% predictive ability to distinguish AP patients from controls. DISCUSSION: AP patients have decreased beneficial nutrient intake and gut microbiome diversity. An increased abundance of H 2 S-producing genera in the AP and SCFA-producing genera in the control group and predictive ability of ML model to distinguish AP patients indicates that diet, gut microbiota, and their end metabolites play a key role in AP.


Asunto(s)
Microbioma Gastrointestinal , Pancreatitis , Animales , Humanos , Pancreatitis/etiología , Estudios de Casos y Controles , Enfermedad Aguda , Dieta , Ácidos Grasos Volátiles
9.
Inorg Chem ; 62(23): 8923-8930, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37246851

RESUMEN

As a result of their optical and redox properties, bipyridyl (bpy) and terpyridyl (tpy) ruthenium complexes play vital roles in numerous domains. Herein, the design and synthesis of two bipyridyl and terpyridyl ruthenium(II) building units L1 and L2 are explained. A [Ru(bpy)3]2+ functionalized triangle S1 and a Sierpinski triangle S2 were synthesized in almost quantitative yields by the self-assembly of L1 with Zn2+ ions and by the heteroleptic self-assembly of L1 and L2 with Zn2+ ions, respectively. The Sierpinski triangle S2 contains the coordination metals [Ru(bpy)3]2+, [Ru(tpy)2]2+, and [Zn(tpy)2]2+. According to research on the catalytic activity of amine oxidation on supramolecules S1 and S2, the benzylamine substrates were nearly entirely transformed to N-benzylidenebenzylamine derivatives after 1 h under a Xe lamp. Furthermore, the observed ruthenium-containing terpyridyl supramolecule S2 maintains high luminous performance at ambient temperature. This discovery opens up new possibilities for the rational molecular design of terpyridyl ruthenium fluorescent materials and catalytic functional materials.

10.
Small Methods ; 7(6): e2201659, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37093170

RESUMEN

The exploration of cost-effective multifunctional electrodes with high activity toward energy storage and conversion systems, such as self-powered alkaline water electrolysis, is very meaningful, although studies remain quite limited. Herein, a heterogeneous nickel-molybdenum (NiMo)-based electrode is fabricated for the first time as a trifunctional electrode for asymmetric supercapacitor (ASC), hydrogen evolution reaction, and oxygen evolution reaction. The trifunctional electrode consists of Ni4 Mo and MoO2 (denoted Ni4 Mo/MoO2 ) with hierarchical nanorod heterostructure and abundant heterogeneous nanointerfaces creating sufficient active sites and efficient charge transfer for achieving high performance self-power electrochemical devices. The ASC consists of the as-prepared Ni4 Mo/MoO2 positive electrode, showing a broad potential window of 1.6 V, and a maximum energy density of 115.6 Wh kg-1 , while the alkaline overall water splitting (OWS) assembled using the as-prepared Ni4 Mo/MoO2 as bifunctional catalysts only requires a low cell voltage of 1.48 V to achieve a current density of 10 mA cm-2 in aqueous alkaline electrolyte. Finally, by integrating the Ni4 Mo/MoO2 -based ASC and OWS devices, an aqueous self-powered OWS is assembled, which self-power the OWS to generate hydrogen gas and oxygen gas, verifying great potential of the as-prepared Ni4 Mo/MoO2 for sustainable and renewable energy storage and conversion system.

11.
BMC Musculoskelet Disord ; 24(1): 234, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36978129

RESUMEN

BACKGROUND: The ability to walk is crucial for maintaining independence and a high quality of life among older adults. Although gait characteristics have been extensively studied in older adults, most studies have investigated muscle activity in the joints of the trunk or the lower limbs without assessing their interactions. Thus, the causes of altered trunk and lower limb movement patterns in older adults remain to explore. Therefore, this study compared the joint kinematic parameters of both trunk and lower limbs between young and older adults to identify kinematic factors associated with changes in gait among older adults. METHODS: In total, 64 older (32 males, aged 68.34 ± 7.38 years; 32 females, aged 67.16 ± 6.66 years) and 64 young (32 males, aged 19.44 ± 0.84 years; 32 females, aged 19.69 ± 0.86 years) healthy adults participated in this study. The range of motion (ROM) of the thorax, pelvis, and trunk in the horizontal plane and of the hip, knee, and ankle joints of the lower limbs in the sagittal plane were measured using a motion capture system with wearable sensors. Two-way analysis of variance assessed differences in ROM by group, sex, and spatio-temporal gait parameters; Pearson correlation analysis assessed the correlation of the trunk and lower limbs. RESULTS: Step length, gait speed, and stride length were greater in young adults (p < 0.001) than in older adults, but older women displayed the fastest gait speed (p < 0.05). ROM values for the pelvis, thorax, trunk, knee joint, and ankle joint of young adults were greater (p < 0.05) than those in older adults. However, hip ROM in older adults was significantly greater than that in young adults (p < 0.05). CONCLUSION: With increasing age, ROM of the lower limbs, especially the ankle joint, decreased significantly, resulting in a significant decrease in gait speed. As ROM of the pelvis decreased, stride length decreased significantly in older adults, who compensate through thoracic rotation. Thus, older adults should enhance muscle strength and increase ROM to improve gait patterns.


Asunto(s)
Marcha , Calidad de Vida , Masculino , Adulto Joven , Humanos , Femenino , Anciano , Marcha/fisiología , Rodilla , Articulación de la Rodilla/fisiología , Rango del Movimiento Articular , Fenómenos Biomecánicos/fisiología
12.
Small Methods ; 7(4): e2201472, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36802208

RESUMEN

Transition metal layered double hydroxides, especially nickel-iron layered double hydroxide (NiFe-LDH) shows significant advancement as efficient oxygen evolution reaction (OER) electrocatalyst but also plays a momentous role as a precursor for NiFe-based hydrogen evolution reaction (HER) catalysts. Herein, a simple strategy for developing Ni-Fe-derivative electrocatalysts via phase evolution of NiFe-LDH under controllable annealing temperatures in an argon atmosphere is reported. The optimized catalyst annealed at 340 o C (denoted NiO/FeNi3 ) exhibits superior HER properties with an ultralow overpotential of 16 mV@10 mA cm-2 . Density functional theory simulation and in situ Raman analyses reveal that the excellent HER properties of the NiO/FeNi3 can be attributed to the strong electronic interaction at the interface of the metallic FeNi3 and semiconducting NiO, which optimizes the H2 O and H adsorption energies for efficient HER and OER catalytic processes. This work will provide rational insights into the subsequent development of related HER electrocatalysts and other corresponding compounds via LDH-based precursors.

13.
PeerJ ; 10: e14520, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36569999

RESUMEN

Aim: The aim of this cross-sectional study was to explore the influence of long-term participating in amateur sports on body posture of school students. Methods: A survey on sport participation was conducted on 1,658 volunteer students aged from 6 to 17 years in two primary schools and one meddle school in Tianjin city. The PA200LE body posture evaluation system and a SpineScanSH-115 electronic spine measuring instrument were used to assess the participants' body posture. According to the survey results and against the inclusion and exclusion criteria, 1,124 eligible participants were divided into seven sport participation groups and seven age-matched control groups for statistical comparisons. Results: Compared with the age-matched controls, the natural standing thoracic kyphosis angle of the swimming group (35.0 ± 9.5 VS 31.2 ± 8.5; t =  - 2.560; p = 0.011) and the football group (34.6 ± 7.2 VS 31.9 ± 7.5; t =  - 2.754; p = 0.006) were found to be significantly larger; the natural standing lumbar lordosis angle (-23.0 ± 11.0 VS -27.0 ± 11.1; t = 0.344; p = 0.024) and the upright sitting lumbar lordosis angle (-11.7 ± 8.4 VS -15.2 ± 12.3; t = 5.738; p = 0.030) of the swimming group was significantly smaller; the upright sitting thoracic kyphosis angle of the running group (25.1 ± 9.3 VS 22.6 ± 9.9; t =  - 1.970; p = 0.050) was significantly larger; the upright sitting thoracic kyphosis angle (23.9 ± 8.9 VS 27.0 ± 7.6; t = 2.096; p = 0.038), the learning position thoracic kyphosis angle (31.0 ± 8.6 VS 37.1 ± 8.9; t = 3.076; p = 0.003), the shoulder level (-1.3 ± 2.1 VS 0.0 ± 2.5; t = 2.389; p = 0.019) and waist level (-1.2 ± 1.7 VS -0.3 ± 1.7; t = 2.511; p = 0.013) of the table tennis group were significantly smaller. Conclusions: The results showed that long-term participation in recreational sports training had an impact on the physical posture of adolescents.


Asunto(s)
Cifosis , Lordosis , Humanos , Adolescente , Estudios Transversales , Postura , Natación
14.
J Orthop Surg Res ; 17(1): 199, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379258

RESUMEN

BACKGROUND: Postural rehabilitation plays an important role in the treatment of non-specific low back pain. Although pelvic inclination has been widely used to improve lumbar lordosis, the effect of cervical anterior inclination on lumbar lordosis in young and older adults in sitting and standing posture is still unclear. This preliminary study was designed to examine the influence of changing the cervical anterior angle on the lumbar lordosis angle, through alterations of the head position under the natural sitting and standing conditions, aiming to provide a basis for establishing a new postural rehabilitation strategy. METHODS: Thirty-six young (24.0 ± 2.2 years, 14 females and 22 males) and 38 older (68.4 ± 5.9 years, 36 females and 2 males) healthy adults participated in this study. The four spinal regional angles-cervical anterior angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic forward inclination angle, were measured in standing and relaxed sitting postures to determine the effects of a postural cueing for the head and neck posture, "inclining head backward and performing chin tuck," on lumbar lordosis angle. RESULTS: In the standing posture, the pelvic forward inclination angle in the older adult group was significantly smaller (P < 0.001, by ANOVA) than that in the young adult group and increased significantly (P < 0.001) in response to the postural cueing. In addition, the thoracic kyphosis angle in the standing (P = 0.001) and sitting (P = 0.003) positions was significantly reduced in response to the postural cueing. However, the lumbar lordosis angle in response to the postural cueing increased significantly in both the standing position (P < 0.001) and sitting position (P < 0.001). CONCLUSION: The results suggest that increasing the cervical anterior angle can increase the lumbar lordosis angle, and the cervical anterior inclination can be used as an alternative to pelvic forward inclination to improve the lumbar lordosis angle. Furthermore, the change in head and neck posture can reduce the thoracic kyphosis angle, making it possible to establish a new noninvasive body posture rehabilitation strategy.


Asunto(s)
Cifosis , Lordosis , Anciano , Femenino , Humanos , Masculino , Cuello , Postura/fisiología , Columna Vertebral/fisiología , Adulto Joven
15.
Small ; 18(9): e2105331, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34913585

RESUMEN

Interfacial engineering and elemental doping are the two parameters to enhance the catalytic behavior of cobalt nitrides for the alkaline hydrogen evolution reaction (HER). However, simultaneously combining these two parameters to improve the HER catalytic properties of cobalt nitrides in alkaline media is rarely reported and also remains challenging in acidic media. Herein, it is demonstrated that high-valence non-3d metal and non-metal integration can simultaneously achieve Co-based nitride/oxide interstitial compound phase boundaries on stainless steel mesh (denoted Mo-Co5.47 N/N-CoO) for efficient HER in alkaline and acidic media. Density functional theory (DFT) calculations show that the unique structure does not only realize multi-active sites, enhanced water dissociation kinetics, and low hydrogen adsorption free energy in alkaline media, but also enhances the positive charge density of hydrogen ions (H+ ) to effectively allow H+ to receive electrons from the catalysts surface toward promoting the HER in acidic media. As a result, the as-prepared Mo-Co5.47 N/N-CoO demands HER overpotential of -28 mV@10 mA cm-2 in an alkaline medium, and superior to the commercial Pt/C at a current density > 44 mA cm-2 in acidic medium. This work paves a useful strategy to design efficient cobalt-based electrocatalysts for HER and beyond.

16.
Small ; 17(26): e2100778, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34060232

RESUMEN

The ever-growing portable electronics and electric vehicle draws the attention of scaling up of energy storage systems with high areal-capacity. The concept of thick electrode designs has been used to improve the active mass loading toward achieving high overall energy density. However, the poor rate capabilities of electrode material owing to increasing electrode thickness significantly affect the rapid transportation of ionic and electron diffusion kinetics. Herein, a new concept named "sub-thick electrodes" is successfully introduced to mitigate the Li-ion storage performance of electrodes. This is achieved by using commercial nickel foam (NF) to develop a monolithic 3D with rich in situ heterogeneous interfaces anode (Cu3 P-Ni2 P-NiO, denoted NF-CNNOP) to reinforce the adhesive force of the active materials on NF as well as contribute additional capacity to the electrode. The as-prepared NF-CNNOP electrode displays high reversible and rate areal capacities of 6.81 and 1.50 mAh cm-2 at 0.40 and 6.0 mA cm-2 , respectively. The enhanced Li-ion storage capability is attributed to the in situ interfacial engineering within the NiO, Ni2 P, and Cu3 P and the 3D consecutive electron conductive network. In addition, cyclic voltammetry, charge-discharge curves, and symmetric cell electrochemical impedance spectroscopy consistently reveal improved pseudocapacitance with enhanced transports kinetics in this sub-thick electrodes.

17.
Mol Autism ; 12(1): 43, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34108004

RESUMEN

BACKGROUND: Neurodevelopmental disorders (NDDs) such as autism spectrum disorder (ASD) display a strong male bias. Androgen exposure is profoundly increased in typical male development, but it also varies within the sexes, and previous work has sought to connect morphological proxies of androgen exposure, including digit ratio and facial morphology, to neurodevelopmental outcomes. The results of these studies have been mixed, and the relationships between androgen exposure and behavior remain unclear. METHODS: Here, we measured both digit ratio masculinity (DRM) and facial landmark masculinity (FLM) in the same neurodevelopmental cohort (N = 763) and compared these proxies of androgen exposure to clinical and parent-reported features as well as polygenic risk scores. RESULTS: We found that FLM was significantly associated with NDD diagnosis (ASD, ADHD, ID; all [Formula: see text]), while DRM was not. When testing for association with parent-reported problems, we found that both FLM and DRM were positively associated with concerns about social behavior ([Formula: see text], [Formula: see text]; [Formula: see text], [Formula: see text], respectively). Furthermore, we found evidence via polygenic risk scores (PRS) that DRM indexes masculinity via testosterone levels ([Formula: see text], [Formula: see text]), while FLM indexes masculinity through a negative relationship with sex hormone binding globulin (SHBG) levels ([Formula: see text], [Formula: see text]). Finally, using the SPARK cohort (N = 9419) we replicated the observed relationship between polygenic estimates of testosterone, SHBG, and social functioning ([Formula: see text], [Formula: see text], and [Formula: see text], [Formula: see text] for testosterone and SHBG, respectively). Remarkably, when considered over the extremes of each variable, these quantitative sex effects on social functioning were comparable to the effect of binary sex itself (binary male: [Formula: see text]; testosterone: [Formula: see text] from 0.1%-ile to 99.9%-ile; SHBG: [Formula: see text] from 0.1%-ile to 99.9%-ile). LIMITATIONS: In the devGenes and SPARK cohorts, our analyses rely on indirect, rather than direct measurement of androgens and related molecules. CONCLUSIONS: These findings and their replication in the large SPARK cohort lend support to the hypothesis that increasing net androgen exposure diminishes capacity for social functioning in both males and females.


Asunto(s)
Andrógenos , Trastorno del Espectro Autista , Estudios de Cohortes , Femenino , Humanos , Masculino , Herencia Multifactorial , Testosterona
18.
ACS Appl Mater Interfaces ; 13(14): 16516-16527, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33783183

RESUMEN

Enabling materials with distinct features toward achieving high-performance energy storage devices is of huge importance but highly challenging. Commercial carbon cloth (CC), because of its appealing chemical and mechanical properties, has been proven to be an excellent conductive substrate for active electrode materials. However, its performance is notably poor when directly used as an electrode in energy storage, due to its low theoretical capacity and surface area. Herein, we successfully endow the CC with enhanced storage capacity via formation of a π-π stacking interaction by integrating electrochemically activated CC (denoted CC/ACC) with biomass-derived carbon (BMDC) (denoted π-CC/ECC@BMDC). The π-CC/ECC@BMDC electrode displays excellent storage performance with a high capacity of 2.53 mAh cm-2 under 0.2 mA cm-2 when used as anode material for lithium ion batteries (LIBs). Due to the induction energy, the negatively charged molecules of the CC/ACC functional groups interact with the BMDC during carbonization, creating the π-π stacking interaction. Based on first-principles calculations, the structural design of the tri-layer carbon enables the movement of electrons around the π-π stacking interaction, which significantly facilitates rapid transportation of electrons, creates three-dimensional (3D) ion tunnels for fast transportation of ions, and improves the electrode's mechanical and electronic properties.

19.
ACS Appl Mater Interfaces ; 12(51): 57093-57101, 2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33296164

RESUMEN

The water dissociation step (H2O + M + e- → M - Hads + OH-) is a crucial one toward achieving high-performance hydrogen evolution reaction (HER). The application of electronic conducting polymers (ECPs), such as polypyrrole (PPy), as the electrocatalyst for HER is rarely reported because of their poor adsorption energy per water molecule, which hinders the Volmer step. Herein, we strongly enrich PPy hollow microspheres (PPy-HMS) with attractive HER activity by enhancing their hydrophilic properties through hybridization with good water affinity SiO2. The as-prepared PPy-coated SiO2 (PPy@SiO2-HMS) achieves a current density of 10 mA cm-2 at -123 mV, which is lower than that of pristine PPy-HMS (-192 mV). Raman and X-ray photospectroscopy analyses reveal that the enhanced HER catalytic capability can be attributed to the strong electronic couplings between PPy and SiO2, and this improves the adsorption energy per water molecule and in turn accelerates the water dissociation kinetics on PPy. This work highlights the potential application of low-cost ECPs as promising electrocatalysts for water electrolysis.

20.
Nanomaterials (Basel) ; 10(11)2020 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-33233419

RESUMEN

Defect-rich photocatalytic materials with excellent charge transfer properties are very popular. Herein, Sm-doped CeO2 nanorods were annealed in a N2 atmosphere to obtain the defective Sm-doped CeO2 photocatalysts (Vo-Sm-CeO2). The morphology and structure of Vo-Sm-CeO2 were systematically characterized. The Vo-Sm-CeO2 nanorods demonstrated an excellent photodegradation performance of methyl blue under visible light irradiation compared to CeO2 nanorods and Sm-CeO2. Reactive oxygen species including OH, ·O2-, and h+ were confirmed to play a pivotal role in the removal of pollutants via electron spin resonance spectroscopy. Doping Sm enhances the conductivity of CeO2 nanorods, benefiting photogenerated electrons being removed from the surface reactive sites, resulting in the superior performance.

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