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1.
Sci Rep ; 14(1): 15001, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951618

RESUMO

Daylight saving time (DST) is currently utilized in many countries with the rationale that it enhances the alignment between daylight hours and activity peaks in the population. The act of transitioning into and out of DST introduces disruptions to the circadian rhythm, thereby impacting sleep and overall health. Despite the substantial number of individuals affected, the consequences of this circadian disruption have often been overlooked. Here, we employ a mathematical model of the human circadian pacemaker to elucidate how the biological clock interacts with daytime and evening exposures to both natural and electrical light. This interaction plays a crucial role in determining the adaptation to the 1 hour time zone shift imposed by the transition to or from DST. In global discussions about DST, there is a prevailing assumption that individuals easily adjust to DST transitions despite a few studies indicating that the human circadian system requires several days to fully adjust to a DST transition. Our study highlights that evening light exposure changes can be the main driving force for re-entrainment, with chronobiological models predicting that people with longer intrinsic period (i.e. later chronotype) entrain more slowly to transitions to or from DST as compared to people with a shorter intrinsic period (earlier chronotype). Moreover, the model forecasts large inter-individual differences in the adaptation speed, in particular during the spring transition. The predictions derived from our model offer circadian biology-based recommendations for light exposure strategies that facilitate a more rapid adaptation to DST-related transitions or travel across a single time zone. As such, our study contributes valuable insights to the ongoing discourse on DST and its implications for human circadian rhythms.


Assuntos
Ritmo Circadiano , Fotoperíodo , Humanos , Ritmo Circadiano/fisiologia , Luz , Sono/fisiologia , Modelos Teóricos , Adaptação Fisiológica , Relógios Biológicos/fisiologia , Relógios Circadianos/fisiologia , Modelos Biológicos
2.
Front Plant Sci ; 13: 1094451, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618612

RESUMO

Iron (Fe) deficiency is a common abiotic stress in plants grown in alkaline soil that causes leaf chlorosis and affects root development due to low plant-available Fe concentration. Silicon (Si) is a beneficial element for plant growth and can also improve plant tolerance to abiotic stress. However, the effect of Si and regulatory mechanisms on tomato plant growth under Fe deficiency remain largely unclear. Here, we examined the effect of Si application on the photosynthetic capacity, antioxidant defense, sugar metabolism, and organic acid contents under Fe deficiency in tomato plants. The results showed that Si application promoted plant growth by increasing photosynthetic capacity, strengthening antioxidant defense, and reprogramming sugar metabolism. Transcriptomics analysis (RNA-seq) showed that Si application under Fe deficiency up-regulated the expression of genes related to antioxidant defense, carbohydrate metabolism and organic acid synthesis. In addition, Si application under Fe deficiency increased Fe distribution to leaves and roots. Combined with physiological assessment and molecular analysis, these findings suggest that Si application can effectively increase plant tolerance to low Fe stress and thus can be implicated in agronomic management of Fe deficiency for sustainable crop production. Moreover, these findings provide important information for further exploring the genes and underlying regulatory mechanisms of Si-mediated low Fe stress tolerance in crop plants.

3.
Nanomicro Lett ; 13(1): 42, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34138223

RESUMO

Potassium-ion capacitors (KICs) are promising for sustainable and eco-friendly energy storage technologies, yet their slow reaction kinetics and poor cyclability induced by large K-ion size are a major obstacle toward practical applications. Herein, by employing black phosphorus nanosheets (BPNSs) as a typical high-capacity anode material, we report that BPNS anodes armored with an ultrathin oriented-grown metal-organic-framework (MOF) interphase layer (BPNS@MOF) exhibit regulated potassium storage behavior for high-performance KICs. The MOF interphase layers as protective layer with ordered pores and high chemical/mechanical stability facilitate K ion diffusion and accommodate the volume change of electrode, beneficial for improved reaction kinetics and enhanced cyclability, as evidenced by substantial characterizations, kinetics analysis and DFT calculations. Consequently, the BPNS@MOF electrode as KIC anodes exhibits outstanding cycle performance outperforming most of the reported state-of-art KICs so far.

4.
Adv Mater ; 33(16): e2007262, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33751682

RESUMO

The exploration of ideal electrode materials overcoming the critical problems of large electrode volume changes and sluggish redox kinetics induced by large ionic radius of Na+ /K+ ions is highly desirable for sodium/potassium-ion batteries (SIBs/PIBs) toward large-scale applications. The present work demonstrates that single-phase ternary cobalt phosphoselenide (CoPSe) in the form of nanoparticles embedded in a layered metal-organic framework (MOF)-derived N-doped carbon matrix (CoPSe/NC) represents an ultrastable and high-rate anode material for SIBs/PIBs. The CoPSe/NC is fabricated by using the MOF as both a template and precursor, coupled with in situ synchronous phosphorization/selenization reactions. The CoPSe anode holds a set of intrinsic merits such as lower mechanical stress, enhanced reaction kinetics, as well as higher theoretical capacity and lower discharge voltage relative to its counterpart of CoSe2 , and suppressed shuttle effect with higher intrinsic electrical conductivity relative to CoPS. The involved mechanisms are evidenced by substantial characterizations and density functional theory (DFT) calculations. Consequently, the CoPSe/NC anode shows an outstanding long-cycle stability and rate performance for SIBs and PIBs. Moreover, the CoPSe/NC-based Na-ion full cell can achieve a higher energy density of 274 Wh kg-1 , surpassing that based on CoSe2 /NC and most state-of-the-art Na-ion full cells based on P-, Se-, or S-containing binary/ternary anodes to date.

5.
ACS Nano ; 14(4): 5111-5120, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32271536

RESUMO

Exploring Si-based anode materials with high electrical conductivity and electrode stability is crucial for high-performance lithium-ion batteries (LIBs). Herein, we propose the fabrication of a Si-based composite where Si porous nanospheres (Si p-NSs) are tightly wrapped by Ti3C2Tx (Tx stands for the surface groups such as -OH, -F) MXene nanosheets (TNSs) through an interfacial assembly strategy. The TNSs as a conductive and robust tight of the Si p-NSs can effectively improve electron transport and electrode stability, as revealed by substantial characterizations and mechanical simulations. Moreover, the TNSs with rich surface groups enable strong interfacial interactions with the Si p-NS component and a pseudocapacitive behavior, beneficial for fast and stable lithium storage. Consequently, the Si p-NS@TNSs electrode with a high Si content of 85.6% exhibits significantly enhanced battery performance compared with the Si p-NSs electrode such as high reversible capacity (1154 mAh g-1 at 0.2 A g-1), long cycling stability (up to 2000 cycles with a 0.026% capacity decay rate per cycle), and excellent rate performances. Notably, the Si p-NS@TNSs electrode-based LIB full cell delivers a high energy uptake of 405 Wh kg-1, many-times higher than that of the Si p-NSs full cell. This work offers a strategy to develop advanced Si-based anode materials with desirable properties for high-performance LIBs.

6.
Biochem Biophys Res Commun ; 521(4): 984-990, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31727371

RESUMO

Diabetic nephropathy (DN) is among the common complications of diabetes and is a major cause of end-stage kidney disease. Emerging data indicate that renal inflammation is involved in DN progression and aggravation. Still, the exact cellular mechanisms remain unclear. Dysregulated expression of microRNAs (miRNAs) is associated with multiple diseases, including DN. The relationship between miRNAs and inflammation in DN is also unexplored. Here, we evaluated the role of miR-485 in mediating the response of human mesangial cells (HMCs) to a high glucose (HG) concentration, and the potential underlying mechanism. We found that miR-485 expression is significantly decreased in HG-stimulated HMCs. Overexpression of miR-485 suppressed HG-induced proliferation of HMCs. Lower production of proinflammatory cytokines (i.e., TNF-α, IL-1ß, and IL-6) was observed in miR-485-overexpressing HMCs. Overexpression of miR-485 markedly suppressed the overexpression of extracellular-matrix proteins, e.g., collagen IV (Col IV) and fibronectin (FN), in HG-stimulated HMCs. Furthermore, miR-485 suppressed the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 5 (NOX5), restrained the HG-induced HMC proliferation, downregulated the expression of proinflammatory cytokines, and inhibited the production of extracellular-matrix proteins in HMCs. These results provide new insights into the involvement of the miR-485-NOX5 signaling pathway in DN progression.


Assuntos
Nefropatias Diabéticas/genética , Inflamação/genética , Inflamação/patologia , Células Mesangiais/metabolismo , Células Mesangiais/patologia , MicroRNAs/metabolismo , Modelos Biológicos , NADPH Oxidase 5/metabolismo , Sequência de Bases , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Nefropatias Diabéticas/patologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/toxicidade , Células HEK293 , Humanos , Células Mesangiais/efeitos dos fármacos , MicroRNAs/genética , Estresse Oxidativo/efeitos dos fármacos
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