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1.
Small ; : e2403020, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804864

RESUMO

Energy conversion from the environment into electricity is the most direct and effective electricity source to sustainably power off-grid electronics, once the electricity requirement exceeds the capability of traditional centralized power supply systems. Normally photovoltaic cells have enabled distributed power generation during the day, but do not work at night. Thus, efficient electricity generation technologies for a sustainable all-day power supply with no necessity for energy storage remain a challenge. Herein, an innovative all-day power generation strategy is reported, which self-adaptively integrates the diurnal photothermal and nocturnal radiative cooling processes into the thermoelectric generator (TEG) via the spectrally dynamic modulated coating, to continuously harvest the energy from the hot sun and the cold universe for power generation. Synergistic with the optimized latent heat phase change material, the electricity generation performance of the TEG is dramatically enhanced, with a maximum power density exceeding 1000 mW m-2 during the daytime and up to 25 mW m-2 during the nighttime, corresponding to an improvement of 123.1% and 249.1%, compared with the conventional strategy. This work maximizes the utilization of ambient energy resources to provide an environmentally friendly and uninterrupted power generation strategy. This opens up new possibilities for sustained power generation both daytime and nighttime.

2.
Cereb Cortex ; 33(14): 9165-9174, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37310142

RESUMO

It has been proved that unilateral hearing loss (UHL) can cause functional connectivity alterations in adults. However, the mechanism of the human brain coping with the challenge of unilateral hearing deprivation at very early developmental phases remains poorly understood. Here, we performed a resting-state functional near-infrared spectroscopy (fNIRS) study on 3- to 10-month-old infants with varying degrees of unilateral hearing loss to investigate the effect of unilateral auditory deprivation in infants. Using network-based statistics, increased functional connectivity was observed in single-sided deafness (SSD) compared with normal hearing infants, and the right middle temporal gyrus was the most involved nodes. In addition, changes in cortical function in infants were related to the degree of hearing loss, with significantly increased functional connectivity in infants with severe to profound unilateral hearing loss compared with the ones with mild to moderate. Moreover, more significant cortical functional recombination changes were found in right-SSD than in left-SSD infants. For the first time, our study provides evidence for the effects of unilateral hearing deprivation on the early cortical development of the human brain, which would also act as a reference for intervention decisions in children with unilateral hearing loss in clinical settings.


Assuntos
Perda Auditiva Unilateral , Perda Auditiva , Adulto , Criança , Humanos , Lactente , Perda Auditiva Unilateral/diagnóstico por imagem , Encéfalo , Mapeamento Encefálico , Tempo
3.
J Am Chem Soc ; 144(22): 9695-9706, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35622083

RESUMO

Selective methane oxidation is difficult chemistry. Here we describe a strategy for the electrocatalysis of selective methane oxidation by immobilizing tricopper catalysts on the cathodic surface. In the presence of dioxygen and methane, the activation of these catalysts above a threshold cathodic potential can initiate the dioxygen chemistry for O atom transfer to methane. The catalytic turnover is completed by facile electron injections into the tricopper catalysts from the electrode. This technology leads to dramatic enhancements in performance of the catalysts toward methane oxidation. Unprecedented turnover frequencies (>40 min-1) and high product throughputs (turnover numbers >30 000 in 12 h) are achieved for this challenging chemical transformation in water under ambient conditions. The technology is green and suitable for on-site direct conversion of methane into methanol.


Assuntos
Metano , Oxigenases , Catálise , Oxirredução , Oxigênio , Oxigenases/metabolismo
4.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614054

RESUMO

Altered metabolism is a hallmark of aging. The tricarboxylic acid cycle (TCA cycle) is an essential metabolic pathway and plays an important role in lifespan regulation. Supplementation of α-ketoglutarate, a metabolite converted by isocitrate dehydrogenase alpha-1 (idha-1) in the TCA cycle, increases lifespan in C. elegans. However, whether idha-1 can regulate lifespan in C. elegans remains unknown. Here, we reported that the expression of idha-1 modulates lifespan and oxidative stress tolerance in C. elegans. Transgenic overexpression of idha-1 extends lifespan, increases the levels of NADPH/NADP+ ratio, and elevates the tolerance to oxidative stress. Conversely, RNAi knockdown of idha-1 exhibits the opposite effects. In addition, the longevity of eat-2 (ad1116) mutant via dietary restriction (DR) was reduced by idha-1 knockdown, indicating that idha-1 may play a role in DR-mediated longevity. Furthermore, idha-1 mediated lifespan may depend on the target of rapamycin (TOR) signaling. Moreover, the phosphorylation levels of S6 kinase (p-S6K) inversely correlate with idha-1 expression, supporting that the idha-1-mediated lifespan regulation may involve the TOR signaling pathway. Together, our data provide new insights into the understanding of idha-1 new function in lifespan regulation probably via DR and TOR signaling and in oxidative stress tolerance in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Isocitrato Desidrogenase , Longevidade , Estresse Oxidativo , Animais , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Longevidade/genética
5.
Front Microbiol ; 15: 1415723, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983623

RESUMO

The physiological and genotypic characteristics of Mangrovibacter (MGB) remain largely unexplored, including their distribution and abundance within ecosystems. M. phragmitis (MPH) ASIOC01 was successfully isolated from activated sludge (AS), which was pre-enriched by adding 1,3-dichloro-2-propanol and 3-chloro-1,2-propanediol as carbon sources. The new isolate, MPH ASIOC01, exhibited resilience in a medium containing sodium chloride concentration up to 11% (with optimal growth observed at 3%) and effectively utilizing glycerol as their sole carbon source. However, species delimitation of MGBs remains challenging due to high 16S rRNA sequence similarity (greater than 99% ANI) among different MGBs. In contrast, among the housekeeping gene discrepancies, the tryptophan synthase beta chain gene can serve as a robust marker for fast species delimitation among MGBs. Furthermore, the complete genome of MPH ASIOC01 was fully sequenced and circlized as a single contig using the PacBio HiFi sequencing method. Comparative genomics revealed genes potentially associated with various phenotypic features of MGBs, such as nitrogen-fixing, phosphate-solubilizing, cellulose-digesting, Cr-reducing, and salt tolerance. Computational analysis suggested that MPH ASIOC01 may have undergone horizontal gene transfer events, possibly contributing unique traits such as antibiotic resistance. Finally, our findings also disclosed that the introduction of MPH ASIOC01 into AS can assist in the remediation of wastewater chemical oxygen demand, which was evaluated using gas chromatograph-mass spectrometry. To the best of our knowledge, this study offers the most comprehensive understanding of the phenotypic and genotypic features of MGBs to date.

6.
ACS Appl Mater Interfaces ; 16(11): 13997-14005, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447142

RESUMO

The efficient generation and active modulation of terahertz (THz) waves are strongly required for the development of various THz applications such as THz imaging/spectroscopy and THz communication. In addition, due to the increasing degree of integration for the THz optoelectronic devices, miniaturizing the complex THz system into a compact unit is also important and necessary. Today, integrating the THz source with the modulator to develop a powerful, easy-to-adjust, and scalable or on-chip THz emitter is still a challenge. As a new type of THz emitter, a spintronic THz emitter has attracted a great deal of attention due to its advantages of high efficiency, ultrawide band, low cost, and easy integration. In this study, we have proposed a multifield-modulated spintronic THz emitter based on the VO2/Ni/Pt multilayer film structure with a wide band region of 0-3 THz. Because of the pronounced phase transition of the integrated VO2 layer, the fabricated THz emitter can be efficiently modulated via thermal or electric stimuli with a modulation depth of about one order of magnitude; the modulation depths under thermal stimulation and electrical stimulation were 91.8% and 97.3%, respectively. It is believed that this multifield modulated spintronic THz emitter will provide various possibilities for the integration of next-generation on-chip THz sources and THz modulators.

7.
Int J Pediatr Otorhinolaryngol ; 172: 111687, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37515869

RESUMO

OBJECTIVES: This study aimed to explore the correlation between the characteristics of cortical auditory evoked potential (CAEP) of children with cochlear implants (CIs) and auditory and speech rehabilitation performance by an objective evaluation technique and subjective auditory and speech skills measurements. METHODS: All participants were recruited from Beijing Children's Hospital, Beijing, China. 19 children with CIs had their responses to the CAEP and MMN recorded. The LittlEARs® Auditory Questionnaire (LEAQ), Categories of Auditory Performance (CAP), Speech Intelligibility Rating Scale (SIR), Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS), and Meaningful Use of Speech Scale (MUSS) measures were taken to assess the children's speech and hearing abilities. RESULTS: P1 and MMN of CAEP were negatively related to the duration of CI usage. The duration of CI usage and scores of auditory-verbal assessment questionnaires all showed significant relationships. Additionally, scores of these questionnaires were significantly inversely associated with the latency of P1 and MMN. CONCLUSION: P1 and MMN could be used as objective methods to evaluate the effectiveness of hearing and speech rehabilitation in children with CIs. In particular to those who cannot give effectively feedback of auditory and verbal effects, these methods might have a certain guiding significance.


Assuntos
Implante Coclear , Implantes Cocleares , Perda Auditiva Neurossensorial , Percepção da Fala , Lactente , Humanos , Implante Coclear/métodos , Perda Auditiva Neurossensorial/cirurgia , Potenciais Evocados Auditivos/fisiologia , Inteligibilidade da Fala
8.
ACS Appl Mater Interfaces ; 15(33): 40062-40069, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37552832

RESUMO

Perovskite quantum dot light-emitting diodes (QLEDs) with high color purity and wide color gamut have good application prospects in the next generation of display technology. However, colloidal perovskite quantum dots (PQDs) may introduce a large number of defects during the film-forming process, which is not conducive to the luminous efficiency of the device. Meanwhile, the disordered film formation of PQDs will form interfacial defects and reduce the device performance. Here, we report an interface-induced crystallinity enhancement (IICE) strategy to increase the crystallinity of PQDs at the hole transport layer (HTL)/PQD interface. As a result, both the Br- vacancies in the PQD film and the interfacial defects were well passivated and the leakage current was also suppressed. We achieved QLEDs with a maximum external quantum efficiency (EQE) of 16.45% and current efficiency (CE) of 61.77 cd/A, showing improved performance to more than twice that of the control devices. The IICE strategy paves a new way to enhance the crystallinity of PQD films, so as to improve the performance of QLEDs for application in the future display field.

10.
Front Nutr ; 10: 1202763, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693247

RESUMO

Background: The aim of this study was to assess the global burden of disease from non-communicable chronic diseases (NCD) due to diet low in fruits from 1990 to 2019. Methods: Based on data from the Global Burden of Disease (GBD) 2019, the global burden of disease due to diet low in fruits was analyzed for each country or region, disaggregated by disease type, age, sex, and year. The number of deaths and disability-adjusted life years (DALYs), population attributable fraction (PAF), age-standardized mortality rate (ASMR) and age-standardized DALY rate (ASDR) were calculated, and the average annual percentage change (AAPC) was calculated to describe trends in ASMR and ASDR from 1990 to 2019. Results: From 1990 to 2019, the number of deaths and DALYs due to diet low in fruits increased by 31.5 and 27.4%, respectively. Among the tertiary diseases, ischemic heart disease, stroke, and diabetes and kidney disease were the top three contributors to the global increase in deaths and DALYs. However, both ASMR and ASDR showed a decreasing trend. The fastest decline in ASMR and ASDR was in stroke, with AAPC of -2.13 (95% CI: -2.22, -2.05, p < 0.05) and -0.56 (95% CI: -0.62, -0.51, p < 0.05), respectively. For GBD regions, high PAF occurred mainly in South Asia, Oceania, and sub-Saharan Africa. Age-specific PAF for stroke and ischemic heart disease death attributable to diet low in fruits was significantly negatively associated with age. Diet low in fruits related ASMR and ASDR showed an M-shaped relationship with the socio-demographic index (SDI), but with an overall decreasing trend. Conclusion: The number of deaths and DALYs due to diet low in fruits continues to increase. Therefore, early nutritional interventions should be implemented by the relevant authorities to reduce the burden of diseases caused by diet low in fruits.

11.
ACS Nano ; 17(10): 9501-9509, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37166276

RESUMO

Extensive use of renewable and clean energy is one of the promising ways to solve energy/environmental problems and promote the sustainable development of our society. As inexhaustible energy sources, the photothermal (PT) and radiative cooling (RC) energy from the sun and outer space have recently attracted tremendous interest. However, these two kinds of energy utilization have distinctly opposite spectral properties, especially in the infrared range, making it extremely difficult to integrate these two energy harvesting modes within a fixed device for continuous energy collection. Thus, in the current study, we have proposed a spectrally self-adaptive broadband absorber/emitter (SSBA/E) based on vanadium dioxide (VO2), a typical phase transition material, to achieve continuous energy harvesting via collecting solar thermal energy in PT mode during the day and obtaining cool energy in wide-band RC mode at night. Experimental results show that owing to the phase transition property of the VO2 layer, these two energy collection modes can be adaptively switched. Specifically, the VO2-based device shows a broadband infrared emissivity modulation from 0.21 to 0.75 and low critical temperatures (58.4 and 49.2 °C) during the phase transition, leading to continuous energy harvesting with high efficiency. Due to the broadband infrared emission, the RC maximum power of the SSBA/E device was estimated to be 58 W m-2. The proposed VO2 smart coatings are also applicable for many other applications such as thermal management of spacecraft, infrared camouflage, or adaptive optical devices.

12.
J Inorg Biochem ; 196: 110691, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31063931

RESUMO

In this study, we describe efforts to clarify the role of the copper cofactors associated with subunit B (PmoB) of the particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) (M. capsulatus). This subunit exhibits strong affinity toward CuI ions. To elucidate the high copper affinity of the subunit, the full-length PmoB, and the N-terminal truncated mutants PmoB33-414 and PmoB55-414, each fused to the maltose-binding protein (MBP), are cloned and over-expressed into Escherichia coli (E. coli) K12 TB1 cells. The Y374F, Y374S and M300L mutants of these protein constructs are also studied. When this E. coli is grown with the pmoB gene in 1.0 mM CuII, it behaves like M. capsulatus (Bath) cultured under high copper stress with abundant membrane accumulation and high CuI content. The recombinant PmoB proteins are verified by Western blotting of antibodies directed against the MBP sub-domain in each of the copper-enriched PmoB proteins. Cu K-edge X-ray absorption near edge spectroscopy (XANES) of the copper ions confirms that all the PmoB recombinants are CuI proteins. All the PmoB proteins show evidence of a "dicopper site" according to analysis of the Cu extended X-ray absorption edge fine structure (EXAFS) of the membranes. No specific activities toward methane and propene oxidation are observed with the recombinant membrane-bound PmoB proteins. However, significant production of hydrogen peroxide is observed in the case of the PmoB33-414 mutant. Reaction of the dicopper site with dioxygen produces hydrogen peroxide and leads to oxidation of the CuI ions residing in the C-terminal sub-domain of the PmoB subunit.


Assuntos
Methylococcus capsulatus/enzimologia , Oxigenases/química , Oxigenases/metabolismo , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Cobre/química , Cobre/metabolismo , Proteínas de Membrana/metabolismo , Oxirredução
13.
Aging Cell ; 13(4): 755-64, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24889782

RESUMO

Target of rapamycin (TOR) signaling is a nutrient-sensing pathway controlling metabolism and lifespan. Although TOR signaling can be activated by a metabolite of diacylglycerol (DAG), phosphatidic acid (PA), the precise genetic mechanism through which DAG metabolism influences lifespan remains unknown. DAG is metabolized to either PA via the action of DAG kinase or 2-arachidonoyl-sn-glycerol by diacylglycerol lipase (DAGL). Here, we report that in Drosophila and Caenorhabditis elegans, overexpression of diacylglycerol lipase (DAGL/inaE/dagl-1) or knockdown of diacylglycerol kinase (DGK/rdgA/dgk-5) extends lifespan and enhances response to oxidative stress. Phosphorylated S6 kinase (p-S6K) levels are reduced following these manipulations, implying the involvement of TOR signaling. Conversely, DAGL/inaE/dagl-1 mutants exhibit shortened lifespan, reduced tolerance to oxidative stress, and elevated levels of p-S6K. Additional results from genetic interaction studies are consistent with the hypothesis that DAG metabolism interacts with TOR and S6K signaling to affect longevity and oxidative stress resistance. These findings highlight conserved metabolic and genetic pathways that regulate aging.


Assuntos
Caenorhabditis elegans/enzimologia , Drosophila melanogaster/enzimologia , Lipase Lipoproteica/metabolismo , Longevidade , Estresse Oxidativo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Adaptação Fisiológica , Animais , Caenorhabditis elegans/fisiologia , Drosophila melanogaster/fisiologia , Epistasia Genética , Técnicas de Silenciamento de Genes , Mutação/genética , Fosforilação , Interferência de RNA , Proteínas Quinases S6 Ribossômicas/metabolismo
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