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1.
Nucleic Acids Res ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166492

RESUMEN

N6-methyladenonsine (m6A) is ubiquitously distributed in mammalian mRNA. However, the precise involvement of m6A in early development has yet to be fully elucidated. Here, we report that deletion of the m6A demethylase ALKBH5 in human embryonic stem cells (hESCs) severely impairs definitive endoderm (DE) differentiation. ALKBH5-/- hESCs fail to undergo the primitive streak (PS) intermediate transition that precedes endoderm specification. Mechanistically, we show that ALKBH5 deficiency induces m6A hypermethylation around the 3' untranslated region (3'UTR) of GATA6 transcripts and destabilizes GATA6 mRNA in a YTHDF2-dependent manner. Moreover, GATA6 binds to the promoters of critical regulatory genes involved in Wnt/ß-catenin signaling transduction, including the canonical Wnt antagonist DKK1 and DKK4, which are unexpectedly repressed upon the dysregulation of GATA6 mRNA metabolism. Remarkably, DKK1 and DKK4 both exhibit a pleiotropic effect in modulating the Wnt/ß-catenin cascade and guard the endogenous signaling activation underlying DE formation as potential downstream targets of the ALKBH5-GATA6 regulation. Here, we unravel a role of ALKBH5 in human endoderm formation in vitro by modulating the canonical Wnt signaling logic through the previously unrecognized functions of DKK1/4, thus capturing a more comprehensive role of m6A in early human embryogenesis.

2.
NPJ Metab Health Dis ; 2(1): 20, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39149696

RESUMEN

Histone deacetylases (HDACs) have a wide range of targets and can rewire both the chromatin and lipidome of cancer cells. In this study, we show that valproic acid (VPA), a brain penetrant anti-seizure medication and histone deacetylase inhibitor, inhibits the growth of IDH1 mutant tumors in vivo and in vitro, with at least some selectivity over IDH1 wild-type tumors. Surprisingly, genes upregulated by VPA showed no enhanced chromatin accessibility at the promoter, but there was a correlation between VPA-downregulated genes and diminished promoter chromatin accessibility. VPA inhibited the transcription of lipogenic genes and these lipogenic genes showed significant decreases in promoter chromatin accessibility only in the IDH1 MT glioma cell lines tested. VPA inhibited the mTOR pathway and a key lipogenic gene, fatty acid synthase (FASN). Both VPA and a selective FASN inhibitor TVB-2640 rewired the lipidome and promoted apoptosis in an IDH1 MT but not in an IDH1 WT glioma cell line. We further find that HDACs are involved in the regulation of lipogenic genes and HDAC6 is particularly important for the regulation of FASN in IDH1 MT glioma. Finally, we show that FASN knockdown alone and VPA in combination with FASN knockdown significantly improved the survival of mice in an IDH1 MT primary orthotopic xenograft model in vivo. We conclude that targeting fatty acid metabolism through HDAC inhibition and/or FASN inhibition may be a novel therapeutic opportunity in IDH1 mutant gliomas.

3.
Microbiol Res ; 286: 127823, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38959523

RESUMEN

Plant-associated streptomycetes play important roles in plant growth and development. However, knowledge of volatile-mediated crosstalk between Streptomyces spp. and plants remains limited. In this study, we investigated the impact of volatiles from nine endophytic Streptomyces strains on the growth and development of plants. One versatile strain, Streptomyces setonii WY228, was found to significantly promote the growth of Arabidopsis thaliana and tomato seedlings, confer salt tolerance, and induce early flowering and increased fruit yield following volatile treatment. Analysis of plant growth-promoting traits revealed that S. setonii WY228 could produce indole-3-acetic acid, siderophores, ACC deaminase, fix nitrogen, and solubilize inorganic phosphate. These capabilities were further confirmed through genome sequencing and analysis. Volatilome analysis indicated that the volatile organic compounds emitted from ISP-2 medium predominantly comprised sesquiterpenes and 2-ethyl-5-methylpyrazine. Further investigations showed that 2-ethyl-5-methylpyrazine and sesquiterpenoid volatiles were the primary regulators promoting growth, as confirmed by experiments using the terpene synthesis inhibitor phosphomycin, pure compounds, and comparisons of volatile components. Transcriptome analysis, combined with mutant and inhibitor studies, demonstrated that WY228 volatiles promoted root growth by activating Arabidopsis auxin signaling and polar transport, and enhanced root hair development through ethylene signaling activation. Additionally, it was confirmed that volatiles can stimulate plant abscisic acid signaling and activate the MYB75 transcription factor, thereby promoting anthocyanin synthesis and enhancing plant salt stress tolerance. Our findings suggest that aerial signaling-mediated plant growth promotion and abiotic stress tolerance represent potentially overlooked mechanisms of Streptomyces-plant interactions. This study also provides an exciting strategy for the regulation of plant growth and the improvement of horticultural crop yields within sustainable agricultural practices.


Asunto(s)
Arabidopsis , Ácidos Indolacéticos , Tolerancia a la Sal , Streptomyces , Compuestos Orgánicos Volátiles , Arabidopsis/crecimiento & desarrollo , Arabidopsis/microbiología , Streptomyces/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Desarrollo de la Planta/efectos de los fármacos , Estrés Salino , Transducción de Señal , Raíces de Plantas/microbiología , Raíces de Plantas/crecimiento & desarrollo , Plantones/crecimiento & desarrollo , Plantones/microbiología , Plantones/metabolismo , Regulación de la Expresión Génica de las Plantas , Liasas de Carbono-Carbono/metabolismo , Fosfatos/metabolismo
4.
Nat Commun ; 15(1): 6200, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39043686

RESUMEN

Cell fate is likely regulated by a common machinery, while components of this machine remain to be identified. Here we report the design and testing of engineered cell fate controller NanogBiD, fusing BiD or BRG1 interacting domain of SS18 with Nanog. NanogBiD promotes mouse somatic cell reprogramming efficiently in contrast to the ineffective native protein under multiple testing conditions. Mechanistic studies further reveal that it facilitates cell fate transition by recruiting the intended Brg/Brahma-associated factor (BAF) complex to modulate chromatin accessibility and reorganize cell state specific enhancers known to be occupied by canonical Nanog, resulting in precocious activation of multiple genes including Sall4, miR-302, Dppa5a and Sox15 towards pluripotency. Although we have yet to test our approach in other species, our findings suggest that engineered chromatin regulators may provide much needed tools to engineer cell fate in the cells as drugs era.


Asunto(s)
Proteína Homeótica Nanog , Factores de Transcripción , Animales , Ratones , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteína Homeótica Nanog/metabolismo , Proteína Homeótica Nanog/genética , Reprogramación Celular/genética , Cromatina/metabolismo , Cromatina/genética , ADN Helicasas/metabolismo , ADN Helicasas/genética , Diferenciación Celular , Ingeniería Celular/métodos , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética
5.
Cell Biosci ; 14(1): 93, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010176

RESUMEN

BACKGROUND: Numerous studies have shown that somite development is a necessary stage of myogenesis chondrogenesis and osteogenesis. Our previous study has established a stable presomitic mesoderm progenitor cell line (UiPSM) in vitro. Naturally, we wanted to explore whether UiPSM cell can develop bone and myogenic differentiation. RESULTS: Selective culture conditions yielded PAX3 and PAX7 positive skeletal muscle precursors from UiPSM cells. The skeletal muscle precursors undergo in vitro maturation resulting in myotube formation. MYOD effectively promoted the maturity of the skeletal myocytes in a short time. We found that UiPSM and MYOD mediated UiPSM cell-derived skeletal myocytes were viable after transplantation into the tibialis anterior muscle of MITRG mice, as assessed by bioluminescence imaging and scRNA-seq. Lack of teratoma formation and evidence of long-term myocytes engraftment suggests considerable potential for future therapeutic applications. Moreover, UiPSM cells can differentiate into osteoblast and chondroblast cells in vitro. CONCLUSIONS: UiPSM differentiation has potential as a developmental model for musculoskeletal development research and treatment of musculoskeletal disorders.

6.
Biomed Environ Sci ; 37(6): 628-638, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38988113

RESUMEN

Objective: Pertussis cases have increased markedly since 2018 in Guangxi. The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population. Method: A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay (ELISA). Results: Of the collected samples, 1,833 (17.94%) tested positive for anti-pertussis IgG, with the median concentration of 16.06 IU/mL. Antibody level < 10 IU/mL accounted for more than 60% in children under 4 years of age, but declined with age, whereas the percentages of the other three levels (10-40, 40-50, and ≥ 50 IU/mL) increased almost with age ( P < 0.001). Moreover, 7,924 samples were selected for anti-pertussis toxin IgG, of which 653 (8.24%) tested positive (≥ 40 IU/mL) with the median concentration of 5.89 IU/mL, and 204 participants (2.56%) had recent pertussis infection (≥ 100 IU/mL). Among the different age groups, the highest rates of positivity and recent infection were observed at 11-20 years of age, the lowest positivity rate at 5 years of age, and the lowest recent infection rate at 4 years of age ( P < 0.001, P = 0.005, respectively). Conclusion: The survey results showed that all age groups in Guangxi lacked immunity against pertussis, which was one of the main factors contributing to the resurgence of pertussis in 2018. In addition, the prevalence of pertussis is relatively high in Guangxi, and its incidence is seriously underestimated, especially in adolescents and adults.


Asunto(s)
Tos Ferina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven , Distribución por Edad , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Bordetella pertussis/inmunología , China/epidemiología , Estudios Transversales , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Vacuna contra la Tos Ferina , Tos Ferina/epidemiología , Tos Ferina/inmunología , Tos Ferina/prevención & control , Humanos
7.
Mater Horiz ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042375

RESUMEN

In the pursuit of effective thermal management for electronic devices, it is crucial to develop insulation thermal interface materials (TIMs) that exhibit exceptional through-plane thermal conductivity, low thermal resistance, and minimal compression modulus. Boron nitride (BN), given its outstanding thermal conduction and insulation properties, has garnered significant attention as a potential material for this purpose. However, previously reported BN-based composites have consistently demonstrated through-plane thermal conductivity below 10 W m-1 K-1 and high compression modulus, whilst also presenting challenges in terms of mass production. In this study, low molecular weight polydimethylsiloxane (PDMS) and large-size BN were utilized as the foundational materials. Utilizing a rolling-curing integrated apparatus, we successfully accomplished the continuous preparation of large-sized, high-adhesion BN films. Subsequent implementation of stacking, cold pressing, and vertical cutting techniques enabled the attainment of a remarkable BN-based TIM, characterized by an unprecedented through-plane thermal conductivity of up to 12.11 W m-1 K-1, remarkably low compression modulus (55 kPa), and total effective thermal resistance (0.16 °C in2 W-1, 50 Psi). During the TIMs performance evaluation, our TIMs demonstrated superior heat dissipation capabilities compared with commercial TIMs. At a heating power density of 40 W cm-2, the steady-state temperature of the ceramic heating element was found to be 7 °C lower than that of the commercial TIMs. This pioneering feat not only contributes valuable technical insights for the development of high-performance insulating TIMs but also establishes a solid foundation for widespread implementation in thermal management applications across a range of electronic devices.

8.
Antioxidants (Basel) ; 13(7)2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39061935

RESUMEN

Assisted reproduction technology (ART) procedures are often impacted by post-ovulatory aging (POA), which can lead to reduced fertilization rates and impaired embryo development. This study used RNA sequencing analysis and experimental validation to study the similarities and differences between in vivo- and vitro-matured porcine oocytes before and after POA. Differentially expressed genes (DEGs) between fresh in vivo-matured oocyte (F_vivo) and aged in vivo-matured oocyte (A_vivo) and DEGs between fresh in vitro-matured oocyte (F_vitro) and aged in vitro-matured oocyte (A_vitro) were intersected to explore the co-effects of POA. It was found that "organelles", especially "mitochondria", were significantly enriched Gene Ontology (GO) terms. The expression of genes related to the "electron transport chain" and "cell redox homeostasis" pathways related to mitochondrial function significantly showed low expression patterns in both A_vivo and A_vitro groups. Weighted correlation network analysis was carried out to explore gene expression modules specific to A_vivo. Trait-module association analysis showed that the red modules were most associated with in vivo aging. There are 959 genes in the red module, mainly enriched in "RNA binding", "mRNA metabolic process", etc., as well as in GO terms, and "spliceosome" and "nucleotide excision repair" pathways. DNAJC7, IK, and DDX18 were at the hub of the gene regulatory network. Subsequently, the functions of DDX18 and DNAJC7 were verified by knocking down their expression at the germinal vesicle (GV) and Metaphase II (MII) stages, respectively. Knockdown at the GV stage caused cell cycle disorders and increase the rate of abnormal spindle. Knockdown at the MII stage resulted in the inefficiency of the antioxidant melatonin, increasing the level of intracellular oxidative stress, and in mitochondrial dysfunction. In summary, POA affects the organelle function of oocytes. A_vivo oocytes have some unique gene expression patterns. These genes may be potential anti-aging targets. This study provides a better understanding of the detailed mechanism of POA and potential strategies for improving the success rates of assisted reproductive technologies in pigs and other mammalian species.

9.
Genes (Basel) ; 15(7)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39062632

RESUMEN

Cytochrome P450 (CYP) is a crucial oxidoreductase enzyme that plays a significant role in plant defense mechanisms. In this study, a specific cytochrome P450 gene (MnCYP710A11) was discovered in mulberry (Morus notabilis). Bioinformatic analysis and expression pattern analysis were conducted to elucidate the involvement of MnCYP710A11 in combating Botrytis cinerea infection. After the infection of B. cinerea, there was a notable increase in the expression of MnCYP710A11. MnCYP710A11 is overexpressed in Arabidopsis and mulberry and strongly reacts to B. cinerea. The overexpression of the MnCYP710A11 gene in Arabidopsis and mulberry led to a substantial enhancement in resistance against B. cinerea, elevated catalase (CAT) activity, increased proline content, and reduced malondialdehyde (MDA) levels. At the same time, H2O2 and O2- levels in MnCYP710A11 transgenic Arabidopsis were decreased, which reduced the damage of ROS accumulation to plants. Furthermore, our research indicates the potential involvement of MnCYP710A11 in B. cinerea resistance through the modulation of other resistance-related genes. These findings establish a crucial foundation for gaining deeper insights into the role of cytochrome P450 in mulberry plants.


Asunto(s)
Arabidopsis , Botrytis , Sistema Enzimático del Citocromo P-450 , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Morus , Enfermedades de las Plantas , Proteínas de Plantas , Botrytis/patogenicidad , Arabidopsis/genética , Arabidopsis/microbiología , Morus/genética , Morus/microbiología , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Especies Reactivas de Oxígeno/metabolismo
10.
Nat Commun ; 15(1): 6365, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075094

RESUMEN

Cell fate decisions remain poorly understood at the molecular level. Embryogenesis provides a unique opportunity to analyze molecular details associated with cell fate decisions. Works based on model organisms have provided a conceptual framework of genes that specify cell fate control, for example, transcription factors (TFs) controlling processes from pluripotency to immunity1. How TFs specify cell fate remains poorly understood. Here we report that SALL4 relies on NuRD (nucleosome-remodeling and deacetylase complex) to interpret BMP4 signal and decide cell fate in a well-controlled in vitro system. While NuRD complex cooperates with SALL4 to convert mouse embryonic fibroblasts or MEFs to pluripotency, BMP4 diverts the same process to an alternative fate, PrE (primitive endoderm). Mechanistically, BMP4 signals the dissociation of SALL4 from NuRD physically to establish a gene regulatory network for PrE. Our results provide a conceptual framework to explore the rich landscapes of cell fate choices intrinsic to development in higher organisms involving morphogen-TF-chromatin modifier pathways.


Asunto(s)
Proteína Morfogenética Ósea 4 , Diferenciación Celular , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2 , Factores de Transcripción , Animales , Ratones , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteína Morfogenética Ósea 4/metabolismo , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/metabolismo , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/genética , Cromatina/metabolismo , Redes Reguladoras de Genes , Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Endodermo/metabolismo , Endodermo/citología , Transducción de Señal , Linaje de la Célula , Proteínas de Unión al ADN
11.
ChemSusChem ; : e202400961, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031879

RESUMEN

Developing low-cost and highly efficient electrocatalysts toward oxygen evolution reaction (OER) is of vital significance for electrochemical water splitting. Herein, we fabricate a heterostructure NiS/Ni(OH)x electrocatalyst (Ni-S-n) with regenerative oxygen vacancies via electro-deposition on nickel foam (NF) followed by a facile NaBH4 reduction. The resulting Ni-S-5 catalyst with appropriate amount of oxygen vacancies (Ovs) exhibits extraordinary activity for alkaline OER with overpotential of 142 mV and 248 mV to reach the current density of 10 mA cm-2 and 100 mA cm-2, respectively. This catalyst also shows remarkable durability with 40 h. After the stability test, the excellent OER performance is well recovered by regenerating the surface oxygen vacancies (Ovs) significantly with additional NaBH4 reduction. The Ni-S-5 catalyst still displays good activity even after repeating it three times (180 h). The surface oxygen vacancies act as vital active sites for OER. A mechanism of Ovs species transformation and regeneration based on the Ni-S-5 catalyst is proposed, which provides a new direction for exploring ultrastable and efficient OER electrocatalysts with renewable active species.

12.
Neuropathol Appl Neurobiol ; 50(3): e12992, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38831600

RESUMEN

PURPOSE: Radiation-induced brain injury, one of the side effects of cranial radiotherapy in tumour patients, usually results in durable and serious cognitive disorders. Microglia are important innate immune-effector cells in the central nervous system. However, the interaction between microglia and neurons in radiation-induced brain injury remains uncharacterised. METHODS AND MATERIALS: We established a microglia-neuron indirect co-culture model to assess the interaction between them. Microglia exposed to radiation were examined for pyroptosis using lactate dehydrogenase (LDH) release, Annexin V/PI staining, SYTOX staining and western blot. The role of nucleotide-binding oligomerisation domain-like receptor family pyrin domain containing 3 (NLRP3) was investigated in microglia exposed to radiation and in mouse radiation brain injury model through siRNA or inhibitor. Mini-mental state examination and cytokines in blood were performed in 23 patients who had experienced cranial irradiation. RESULTS: Microglia exerted neurotoxic features after radiation in the co-culture model. NLRP3 was up-regulated in microglia exposed to radiation, and then caspase-1 was activated. Thus, the gasdermin D protein was cleaved, and it triggered pyroptosis in microglia, which released inflammatory cytokines. Meanwhile, treatment with siRNA NLRP3 in vitro and NLRP3 inhibitor in vivo attenuated the damaged neuron cell and cognitive impairment, respectively. What is more, we found that the patients after radiation with higher IL-6 were observed to have a decreased MMSE score. CONCLUSIONS: These findings indicate that radiation-induced pyroptosis in microglia may promote radiation-induced brain injury via the secretion of neurotoxic cytokines. NLRP3 was evaluated as an important mediator in radiation-induced pyroptosis and a promising therapeutic target for radiation-induced brain injury.


Asunto(s)
Lesiones Encefálicas , Microglía , Proteína con Dominio Pirina 3 de la Familia NLR , Piroptosis , Piroptosis/efectos de la radiación , Piroptosis/fisiología , Microglía/metabolismo , Microglía/efectos de la radiación , Microglía/patología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Animales , Ratones , Humanos , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Lesiones Encefálicas/etiología , Masculino , Neuronas/metabolismo , Neuronas/patología , Neuronas/efectos de la radiación , Técnicas de Cocultivo , Traumatismos por Radiación/patología , Traumatismos por Radiación/metabolismo , Femenino , Ratones Endogámicos C57BL , Persona de Mediana Edad
14.
Hum Brain Mapp ; 45(8): e26750, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38853710

RESUMEN

The triple-network model has been widely applied in neuropsychiatric disorders including autism spectrum disorder (ASD). However, the mechanism of causal regulations within the triple-network and their relations with symptoms of ASD remains unclear. 81 male ASD and 80 well matched typically developing control (TDC) were included in this study, recruited from Autism Brain Image Data Exchange-I datasets. Spatial reference-based independent component analysis was used to identify the anterior and posterior part of default-mode network (aDMN and pDMN), salience network (SN), and bilateral executive-control network (ECN) from resting-state functional magnetic resonance imaging data. Spectral dynamic causal model and parametric empirical Bayes with Bayesian model reduction/average were adopted to explore the effective connectivity (EC) within triple-network and the relationship between EC and autism diagnostic observation schedule (ADOS) scores. After adjusting for age and site effect, ASD and TDC groups both showed inhibition patterns. Compared with TDC, ASD group showed weaker self-inhibition in aDMN and pDMN, stronger inhibition in pDMN→aDMN, weaker inhibition in aDMN→LECN, pDMN→SN, LECN→SN, and LECN→RECN. Furthermore, negative relationships between ADOS scores and pDMN self-inhibition strength, as well as with the EC of pDMN→aDMN were observed in ASD group. The present study reveals imbalanced effective connections within triple-networks in ASD children. More attentions should be focused at the pDMN, which modulates the core symptoms of ASD and may serve as an important region for ASD diagnosis and the target region for ASD treatments.


Asunto(s)
Trastorno del Espectro Autista , Red en Modo Predeterminado , Imagen por Resonancia Magnética , Humanos , Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno del Espectro Autista/fisiopatología , Masculino , Niño , Red en Modo Predeterminado/diagnóstico por imagen , Red en Modo Predeterminado/fisiopatología , Conectoma , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Función Ejecutiva/fisiología , Adolescente , Teorema de Bayes
15.
Nat Commun ; 15(1): 5225, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890272

RESUMEN

Economic productivity depends on reliable access to electricity, but the extreme shortage events of variable wind-solar systems may be strongly affected by climate change. Here, hourly reanalysis climatological data are leveraged to examine historical trends in defined extreme shortage events worldwide. We find uptrends in extreme shortage events regardless of their frequency, duration, and intensity since 1980. For instance, duration of extreme low-reliability events worldwide has increased by 4.1 hours (0.392 hours per year on average) between 1980-2000 and 2001-2022. However, such ascending trends are unevenly distributed worldwide, with a greater variability in low- and middle-latitude developing countries. This uptrend in extreme shortage events is driven by extremely low wind speed and solar radiation, particularly compound wind and solar drought, which however are strongly disproportionated. Only average 12.5% change in compound extremely low wind speed and solar radiation events may give rise to over 30% variability in extreme shortage events, despite a mere average 1.0% change in average wind speed and solar radiation. Our findings underline that wind-solar systems will probably suffer from weakened power security if such uptrends persist in a warmer future.

16.
ACS Appl Mater Interfaces ; 16(24): 31419-31427, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38836569

RESUMEN

Silver nanowire (AgNW) transparent electrodes are considered as a promising candidate for applications in flexible optoelectronic devices. However, it remains a great challenge to obtain flexible AgNW electrodes with excellent optoelectrical properties and mechanical flexibility. Here, highly stable Ag nanoparticle (AgNP)-enhanced plasmonic AgNW electrodes are demonstrated via the controllable in situ growth of AgNPs at the AgNW junctions and introduction of an l-histidine (l-His) wrapping layer. The flexible transparent electrodes of AgNW-AgNP/l-His possess a low sheet resistance (Rsh) of ∼17.5 Ω sq-1, a high transmittance of ∼92.5% (550 nm), and a robust mechanical stability (100,000 bending cycles). Benefiting from plasmon-coupling effects, flexible polymer light-emitting devices (FPLEDs) with AgNW-AgNP/l-His electrodes present a current efficiency (CE) of ∼14.8 cd A-1 and an external quantum efficiency (EQE) of ∼5.6%, constituting ∼80% and ∼75% increases compared to those of the reference devices with AgNW electrodes, respectively. Additionally, the laminated flexible transparent PLEDs (FT-PLEDs) are demonstrated by integrating polydimethylsiloxane/AgNW-AgNP anodes by a soft lamination process. The FT-PLEDs present a CE of ∼7.1 cd A-1 (cathode side: ∼3.9 cd A-1; anode side: ∼3.2 cd A-1) and an EQE of ∼2.7% (cathode side: ∼1.5%; anode side: ∼1.2%). Furthermore, the FPLEDs and FT-PLEDs exhibit robust mechanical durability, maintaining ∼89% and ∼86% of their initial luminance after 1000 bending cycles at a bending radius of 2 mm, respectively. This work opens up a new avenue for the development of high performance and stable flexible optoelectronic devices.

17.
Adv Sci (Weinh) ; : e2402378, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940415

RESUMEN

Multiplexing technology creates several orthogonal data channels and dimensions for high-density information encoding and is irreplaceable in large-capacity information storage, and communication, etc. The multiplexing dimensions are constructed by light attributes and spatial dimensions. However, limited by the degree of freedom of interaction between light and material structure parameters, the multiplexing dimension exploitation method is still confused. Herein, a 7D Spin-multiplexing technique is proposed. Spin structures with four independent attributes (color center type, spin axis, spatial distribution, and dipole direction) are constructed as coding basic units. Based on the four independent spin physical effects, the corresponding photoluminescence wavelength, magnetic field, microwave, and polarization are created into four orthogonal multiplexing dimensions. Combined with the 3D of space, a 7D multiplexing method is established, which possesses the highest dimension number compared with 6 dimensions in the previous study. The basic spin unit is prepared by a self-developed laser-induced manufacturing process. The free state information of spin is read out by four physical quantities. Based on the multiple dimensions, the information is highly dynamically multiplexed to enhance information storage efficiency. Moreover, the high-dynamic in situ image encryption/marking is demonstrated. It implies a new paradigm for ultra-high-capacity storage and real-time encryption.

18.
Micromachines (Basel) ; 15(6)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38930649

RESUMEN

Visualizing the near-field distribution of microwave field in a monopole antenna is very important for antenna design and manufacture. However, the traditional method of measuring antenna microwave near field distribution by mechanical scanning has some problems, such as long measurement time, low measurement accuracy and large system volume, which seriously limits the measurement effect of antenna microwave near field distribution. In this paper, a method of microwave near-field imaging of a monopole antenna using a nitrogen-vacancy center diamond is presented. We use the whole diamond as a probe and camera to achieve wide-field microwave imaging. Because there is no displacement structure in the system, the method has high time efficiency and good stability. Compared with the traditional measurement methods, the diamond probe has almost no effect on the measured microwave field, which realizes the accurate near-field imaging of the microwave field of the monopole antenna. This method achieves microwave near-field imaging of a monopole antenna with a diameter of 100 µm and a length of 15 mm at a field of view of 5 × 5 mm, with a spatial resolution of 3 µm and an imaging bandwidth of 2.7~3.2 GHz, and an optimal input microwave phase resolution of 0.52° at a microwave power of 0.8494 W. The results provide a new method for microwave near-field imaging and measurement of monopole antennas.

19.
Opt Lett ; 49(11): 2966-2969, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824304

RESUMEN

Over the past decades, spin qubits in silicon carbide (SiC) have emerged as promising platforms for a wide range of quantum technologies. The fluorescence intensity holds significant importance in the performance of quantum photonics, quantum information process, and sensitivity of quantum sensing. In this work, a dual-layer Au/SiO2 dielectric cavity is employed to enhance the fluorescence intensity of a shallow silicon vacancy ensemble in 4H-SiC. Experimental results demonstrate an effective fourfold augmentation in fluorescence counts at saturating laser power, corroborating our theoretical predictions. Based on this, we further investigate the influence of dielectric cavities on the contrast and linewidth of optically detected magnetic resonance (ODMR). There is a 1.6-fold improvement in magnetic field sensitivity. In spin echo experiments, coherence times remain constant regardless of the thickness of dielectric cavities. These experiments pave the way for broader applications of dielectric cavities in SiC-based quantum technologies.

20.
Microorganisms ; 12(6)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38930443

RESUMEN

Protected areas are widely considered an essential strategy for biodiversity conservation. Dictyostelids are unique protists known to have important ecological functions in promoting soil and plant health through their top-down regulation of ecosystem processes, such as decomposition, that involve bacterial populations. But the relationship between dictyostelid diversity within protected areas remains poorly understood, especially on a large scale. Herein, we report data on the distribution of dictyostelids, identified with ITS + SSU rRNA molecular and morphology-based taxonomy, from soil samples collected in the Fanjing Mountain protected area of Guizhou Province, Southwest China. We compared the biodiversity data of dictyostelids in Fanjing Mountain with similar data from previously sampled sites in four other protected areas, including Changbai Mountain (CB), Gushan Mountain (GS), Baiyun Mountain (BY), and Qinghai-Tibet Plateau (QT) in China. We identified four species of dictyostelids belonging to three genera (Dictyostelium, Heterostelium, and Polysphondylium) and herein provide information on the taxonomy of these species. Two species (Heterostelium pallidum and Dictyostelium purpureum) are common and widely distributed throughout the world, but one species (Polysphondylium fuscans) was new to China. Our data indicate that there is no distinguishable significant correlation between the dictyostelid species studied and environmental factors. Overall, the similarity index between Baiyun Mountain in Henan Province and Fanjing Mountain in Guizhou Province, located at approximately the same longitude, is the highest, and the Jaccard similarity coefficients (Jaccard index) of family, genus, and species are 100%, 100%, and 12.5%, respectively. From a species perspective, species in the same climate zone are not closely related, but obvious geographical distributions are evident in different climate zones. This preliminary study provided evidence of the ecological adaptation of dictyostelids to different biological niches.

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