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1.
PLoS Pathog ; 20(4): e1012138, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38640110

RESUMEN

Proper transcription orchestrated by RNA polymerase II (RNPII) is crucial for cellular development, which is rely on the phosphorylation state of RNPII's carboxyl-terminal domain (CTD). Sporangia, developed from mycelia, are essential for the destructive oomycetes Phytophthora, remarkable transcriptional changes are observed during the morphological transition. However, how these changes are rapidly triggered and their relationship with the versatile RNPII-CTD phosphorylation remain enigmatic. Herein, we found that Phytophthora capsici undergone an elevation of Ser5-phosphorylation in its uncanonical heptapeptide repeats of RNPII-CTD during sporangia development, which subsequently changed the chromosomal occupation of RNPII and primarily activated transcription of certain genes. A cyclin-dependent kinase, PcCDK7, was highly induced and phosphorylated RNPII-CTD during this morphological transition. Mechanistically, a novel DCL1-dependent microRNA, pcamiR1, was found to be a feedback modulator for the precise phosphorylation of RNPII-CTD by complexing with PcAGO1 and regulating the accumulation of PcCDK7. Moreover, this study revealed that the pcamiR1-CDK7-RNPII regulatory module is evolutionarily conserved and the impairment of the balance between pcamiR1 and PcCDK7 could efficiently reduce growth and virulence of P. capsici. Collectively, this study uncovers a novel and evolutionary conserved mechanism of transcription regulation which could facilitates correct development and identifies pcamiR1 as a promising target for disease control.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38641052

RESUMEN

PURPOSE: To identify the predictors of infectious disease-specific health literacy (IDSHL), and establish an easy-to-apply nomogram to predict the IDSHL of older adults. METHODS: This cross-sectional study included 380 older adults who completed the IDSHL, self-rated health, sociodemographic and other questionnaires. Logistic regression was used to identify the IDSHL predictors. Nomogram was used to construct a predictive model. RESULTS: Up to 70.1% of older adults had limited IDSHL. Age, education, place of residence, self-rated health, and Internet access were the important influencing factors of IDSHL. The established nomogram model showed high accuracy (receiver operating characteristic curve: 0.848). CONCLUSIONS: The IDSHL of Chinese older adults was significantly deficient. The constructed nomogram is an intuitive tool for IDSHL prediction that can not only contribute towards rapid screening of high-risk older adults with limited IDSHL but also provide guidance for healthcare providers to develop prevention strategies for infectious diseases.

3.
Adv Mater ; : e2401118, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641859

RESUMEN

As an empirical tool in materials science and engineering, the iconic phase diagram owes its robustness and practicality to the topological characteristics rooted in the celebrated Gibbs phase law (F = C - P + 2). When crossing the phase diagram boundary, the structure transition occurs abruptly, bringing about an instantaneous change in physical properties and limited controllability on the boundaries (F = 1). Here, we expand the sharp phase boundary to an amorphous transition region (F = 2) by partially disrupting the long-range translational symmetry, leading to a sequential crystalline-amorphous-crystalline (CAC) transition in a pressurized In2Te5 single crystal. Through detailed in-situ synchrotron diffraction, we elucidate that the phase transition stems from the rotation of immobile blocks [In2Te2]2+, linked by hinge-like [Te3]2- trimers. Remarkably, within the amorphous region, the amorphous phase demonstrates a notable 25% increase of the superconducting transition temperature (Tc), while the carrier concentration remains relatively constant. Furthermore, we propose a theoretical framework revealing that the unconventional boost in amorphous superconductivity might be attributed to an intensified electron correlation, triggered by a disorder-augmented multifractal behavior. These findings underscore the potential of disorder and prompt further exploration of unforeseen phenomena on the phase boundaries. This article is protected by copyright. All rights reserved.

4.
Adv Mater ; : e2401982, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609077

RESUMEN

Corrosion activities and biofouling pose significant challenges for marine facilities, resulting in substantial economic losses. Inspired by the "brick&mortar" structure of pearls, a novel nanocomposite coating (Pun-HJTx) with long-lasting anticorrosion and intelligent antifouling modes is fabricated by integrating a compatible MoS2/MXene heterostructure as the "brick" into a polyurea-modified PDMS (Pun) acting as "mortar." Notably, the presence of multiple hydrogen bonds within the coating effectively reduces the pinholes resulted from solution volatilizing. In the dark, where fouling adhesion and microbial corrosion activities are weakened, the MoS2/MXene plays a role in contact bactericidal action. Conversely, during daylight when fouling adhesion and microbial corrosion activities intensify, the coating releases reactive oxygen species (such as hydroxyl radicals and superoxide ions) to counteract fouling adhesion. Additionally, the coating exhibits multisource self-healing performance under heated or exposed to light (maximum self-healing rate can reach 99.46%) and proves efficient self-cleaning performance and adhesion strength (>2.0 Mpa), making it highly suitable for various practical marine applications. Furthermore, the outstanding performance of the Pun-HJT1 is maintained for ≈180 days in real-world marine conditions, which proving its practicality and feasibility in real shallow sea environments.

5.
J Am Chem Soc ; 146(14): 9721-9727, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38556809

RESUMEN

The volumetric density of the metal atomic site is decisive to the operating efficiency of the photosynthetic nanoreactor, yet its rational design and synthesis remain a grand challenge. Herein, we report a shell-regulating approach to enhance the volumetric density of Co atomic sites onto/into multishell ZnxCd1-xS for greatly improving CO2 photoreduction activity. We first establish a quantitative relation between the number of shell layers, specific surface areas, and volumetric density of atomic sites on multishell ZnxCd1-xS and conclude a positive relation between photosynthetic performance and the number of shell layers. The triple-shell ZnxCd1-xS-Co1 achieves the highest CO yield rate of 7629.7 µmol g-1 h-1, superior to those of the double-shell ZnxCd1-xS-Co1 (5882.2 µmol g-1 h-1) and single-shell ZnxCd1-xS-Co1 (4724.2 µmol g-1 h-1). Density functional theory calculations suggest that high-density Co atomic sites can promote the mobility of photogenerated electrons and enhance the adsorption of Co(bpy)32+ to increase CO2 activation (CO2 → CO2* → COOH* → CO* → CO) via the S-Co-bpy interaction, thereby enhancing the efficiency of photocatalytic CO2 reduction.

6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 467-472, 2024 Apr 10.
Artículo en Chino | MEDLINE | ID: mdl-38565514

RESUMEN

OBJECTIVE: To analyze the clinical phenotype and genotypes of two children with Carnitine-acylcarnitine translocase deficiency (CACTD). METHODS: Two children diagnosed with CACTD at the Gansu Provincial Maternal and Child Health Care Hospital respectively on January 3 and November 19, 2018 were selected as the study subjects. Trio-whole exome sequencing (trio-WES) was carried out, and candidate variants were validated through Sanger sequencing and pathogenicity analysis. RESULTS: Both children were males and had manifested mainly with hypoglycemia. Trio-WES and Sanger sequencing showed that child 1 had harbored compound heterozygous variants of the SLC25A20 gene, namely c.49G>C (p.Gly17Arg) and c.106-2A>G, which were inherited from his father and mother, respectively. Child 2 had harbored homozygous c.199-10T>G variants of the SLC25A20 gene, which were inherited from both of his parents. Among these, the c.106-2A>G and c.49G>C variants were unreported previously. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.49G>C (p.Gly17Arg), c.106-2A>G, and c.199-10T>G variants were classified as likely pathogenic (PM2_supporting+PP3+PM3_strong+PP4), pathogenic (PVS1+PM2_supporting+PM5+PP3), and pathogenic (PVS1+PM2_supporting+PP3+PP5), respectively. CONCLUSION: Combined with their clinical phenotype and genetic analysis, both children were diagnosed with CACTD. Above finding has provided a basis for their treatment as well as genetic counseling and prenatal diagnosis for their families.


Asunto(s)
Carnitina Aciltransferasas/deficiencia , Asesoramiento Genético , Genómica , Errores Innatos del Metabolismo Lipídico , Niño , Masculino , Femenino , Embarazo , Humanos , Linaje , Madres , Mutación , Proteínas de Transporte de Membrana
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 456-460, 2024 Apr 10.
Artículo en Chino | MEDLINE | ID: mdl-38565512

RESUMEN

OBJECTIVE: To explore the genetic basis for a patient with autosomal dominant retinitis pigmentosa (RP). METHODS: A male patient with RP treated at Gansu Provincial Maternal and Child Health Care Hospital in September 2019 was selected as the study subject. Clinical data was collected. Peripheral blood samples of the patient and his parents were subjected to whole exome sequencing (WES). Candidate variant was validated by Sanger sequencing and bioinformatic analysis. RESULTS: The patient, a 29-year-old male, developed night blindness, amblyopia, visual field defects and optic disc abnormalities since childhood. Gene sequencing revealed that he has harbored a heterozygous c.942G>C (p.Lys314Asn) variant of the IMPDH1 gene, which was inherited from his mother, whilst his father was of the wild type. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.942G>C variant was predicted as likely pathogenic (PM1+PM2_Supporting+PP3+PP1). CONCLUSION: The c.942G>C (p.Lys314Asn) variant in the IMPDH1 gene probably underlay the RP in this patient.


Asunto(s)
Retinitis Pigmentosa , Adulto , Femenino , Humanos , Masculino , Biología Computacional , Genómica , Heterocigoto , IMP Deshidrogenasa , Madres , Mutación , Retinitis Pigmentosa/genética
8.
Small ; : e2401815, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38573922

RESUMEN

Currently, research on thermal interface materials (TIMs) is primarily focused on enhancing thermal conductivity. However, strong adhesion and multifunctionality are also important characteristics for TIMs when pursing more stable interface heat conduction. Herein, a novel poly(urethane-urea-imide) (PUUI) elastomer containing abundant dynamic hydrogen bonds network and reversible disulfide linkages is successfully synthesized for application as a TIM matrix. The PUUI can self-adapt to the metal substrate surface at moderate temperatures (80 °C) and demonstrates a high adhesion strength of up to 7.39 MPa on aluminum substrates attributed its noncovalent interactions and strong intrinsic cohesion. Additionally, the PUUI displays efficient self-healing capability, which can restore 94% of its original mechanical properties after self-healing for 6 h at room temperature. Furthermore, PUUI composited with aluminum nitride and liquid metal hybrid fillers demonstrates a high thermal conductivity of 3.87 W m-1 K-1 while maintaining remarkable self-healing capability and adhesion. When used as an adhesive-type TIM, it achieves a low thermal contact resistance of 22.1 mm2 K W-1 at zero pressure, only 16.7% of that of commercial thermal pads. This study is expected to break the current research paradigm of TIMs and offers new insights for the development of advanced, reliable, and sustainable TIMs.

9.
Angew Chem Int Ed Engl ; : e202402841, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647519

RESUMEN

The controlled synthesis of metal nanomaterials with unconventional phases is of significant importance to develop high-performance catalysts for various applications. However, it remains challenging to modulate the atomic arrangements of metal nanomaterials, especially the alloy nanostructures that involve different metals with distinct redox potentials. Here we report the general one-pot synthesis of IrNi, IrRhNi and IrFeNi alloy nanobranches with unconventional hexagonal close-packed (hcp) phase. Notably, the as-synthesized hcp IrNi nanobranches demonstrate excellent catalytic performance towards electrochemical nitrite reduction (NO2RR), with superior NH3 Faradaic efficiency and yield rate of 98.2% and 34.6 mg h-1 mgcat-1 (75.5 mg h-1 mgIr-1) at 0 and -0.1 V (vs reversible hydrogen electrode), respectively. Ex/in-situ characterizations and theoretical calculations reveal that the Ir-Ni interactions within hcp IrNi alloy improve electron transfer to benefit both nitrite activation and active hydrogen generation, leading to a stronger reaction trend of NO2RR by greatly reducing energy barriers of rate-determining step.

10.
Nat Commun ; 15(1): 3257, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627413

RESUMEN

Biological nervous system outperforms in both dynamic and static information perception due to their capability to integrate the sensing, memory and processing functions. Reconfigurable neuromorphic transistors, which can be used to emulate different types of biological analogues in a single device, are important for creating compact and efficient neuromorphic computing networks, but their design remains challenging due to the need for opposing physical mechanisms to achieve different functions. Here we report a neuromorphic electrolyte-gated transistor that can be reconfigured to perform physical reservoir and synaptic functions. The device exhibits dynamics with tunable time-scales under optical and electrical stimuli. The nonlinear volatile property is suitable for reservoir computing, which can be used for multimodal pre-processing. The nonvolatility and programmability of the device through ion insertion/extraction achieved via electrolyte gating, which are required to realize synaptic functions, are verified. The device's superior performance in mimicking human perception of dynamic and static multisensory information based on the reconfigurable neuromorphic functions is also demonstrated. The present study provides an exciting paradigm for the realization of multimodal reconfigurable devices and opens an avenue for mimicking biological multisensory fusion.

11.
J Hazard Mater ; 470: 134223, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38593664

RESUMEN

Elemental carbon (EC) and metals are two important parts of atmospheric black carbon (BC). However, little information is available regarding the interaction between them and its impacts on the reactive oxygen species (ROS) formation and physiological antioxidants depletion. In this study, we chose six most frequently detected metals (Cu(Ⅱ), Fe(Ⅲ), Mn(Ⅱ), Cr(Ⅲ), Pb(Ⅱ) and Zn(Ⅱ)) in BC and examined their interactions with EC in the ROS generation and glutathione (GSH) oxidation. Results showed that only Cu(Ⅱ) and EC synergically promoted the GSH oxidation and hydroxyl radical (•OH) generation. Other five metals had negligible effects on the GSH oxidation regardless of the presence or absence of EC. The synergistic interaction between Cu(Ⅱ) and EC could be attributed to the superior electrical conductivity of EC. In the process, EC transferred electrons from the adjacent GSH to Cu(Ⅱ) through its graphitic carbon framework to yield Cu(Ⅰ) and GSH radical. Cu(Ⅰ) further reacted with dioxygen to generate •OH, which eventually led to the oxidation of GSH. Our results revealed a new driving force inducing the ROS formation and GSH depletion as well as provided novel insights into the risk assessment of BC.

12.
Nat Mater ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589541

RESUMEN

Robust ferroelectricity in nanoscale fluorite oxide-based thin films enables promising applications in silicon-compatible non-volatile memories and logic devices. However, the polar orthorhombic (O) phase of fluorite oxides is a metastable phase that is prone to transforming into the ground-state non-polar monoclinic (M) phase, leading to macroscopic ferroelectric degradation. Here we investigate the reversibility of the O-M phase transition in ZrO2 nanocrystals via in situ visualization of the martensitic transformation at the atomic scale. We reveal that the reversible shear deformation pathway from the O phase to the monoclinic-like (M') state, a compressive-strained M phase, is protected by 90° ferroelectric-ferroelastic switching. Nevertheless, as the M' state gradually accumulates localized strain, a critical tensile strain can pin the ferroelastic domain, resulting in an irreversible M'-M strain relaxation and the loss of ferroelectricity. These findings demonstrate the key role of ferroelastic switching in the reversibility of phase transition and also provide a tensile-strain threshold for stabilizing the metastable ferroelectric phase in fluorite oxide thin films.

13.
Nat Mater ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589543

RESUMEN

Unconventional 1T'-phase transition metal dichalcogenides (TMDs) have aroused tremendous research interest due to their unique phase-dependent physicochemical properties and applications. However, due to the metastable nature of 1T'-TMDs, the controlled synthesis of 1T'-TMD monolayers (MLs) with high phase purity and stability still remains a challenge. Here we report that 4H-Au nanowires (NWs), when used as templates, can induce the quasi-epitaxial growth of high-phase-purity and stable 1T'-TMD MLs, including WS2, WSe2, MoS2 and MoSe2, via a facile and rapid wet-chemical method. The as-synthesized 4H-Au@1T'-TMD core-shell NWs can be used for ultrasensitive surface-enhanced Raman scattering (SERS) detection. For instance, the 4H-Au@1T'-WS2 NWs have achieved attomole-level SERS detections of Rhodamine 6G and a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins. This work provides insights into the preparation of high-phase-purity and stable 1T'-TMD MLs on metal substrates or templates, showing great potential in various promising applications.

14.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(3): 306-311, 2024 Mar 10.
Artículo en Chino | MEDLINE | ID: mdl-38448019

RESUMEN

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with co-morbid Ornithine carbamoyl transferase deficiency (OTCD) and MECP2 duplication syndrome. METHODS: A proband who was admitted to the Neonatal Intensive Care Unit of Gansu Provincial Maternal and Child Health Care Hospital on December 19, 2017 was selected as the study subject. High-throughput sequencing and multiplex ligation-dependent probe amplification (MLPA) were carried out for her pedigree, and short tandem repeat-based linkage analysis and chromosome copy number variation sequencing (CNV-seq) were used for the prenatal diagnosis. RESULTS: The proband, a 3-day-old female, was found to harbor heterozygous deletion of exons 7-9 of the OTC gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PVS1+PM2_Supporting+PP4). The proband was diagnosed with OTCD , which was in keeping with her acute encephalopathy and metabolic abnormalities (manifesting as hyperammonemia, decreased blood citrulline, and increased urine orotic acid). Prenatal diagnosis was carried out for the subsequent pregnancy. The fetus did not harbor the exons 7-9 deletion of the OTC gene, but was found to carry a duplication in Xq28 region (which encompassed the whole region of MECP2 duplication syndrome) and was positive for the SRY sequence. The same duplication was also found in the proband and her mother. Considering the possible existence of X-chromosome inactivation, the proband was diagnosed with two X-linked recessive disorders including OTCD and MECP2 duplication syndrome, and the fetus was determined as a male affected with the MECP2 duplication syndrome. CONCLUSION: Discoveries of the pathogenic variants underlying the OTCD and MECP2 duplication syndrome have enabled clinical intervention, treatment, genetic counseling and prenatal diagnosis for this pedigree.


Asunto(s)
Transferasas de Carboxilo y Carbamoilo , Retraso Mental Ligado al Cromosoma X , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa , Niño , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , China , Variaciones en el Número de Copia de ADN , Ornitina , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/diagnóstico , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/genética , Linaje , Diagnóstico Prenatal
15.
Light Sci Appl ; 13(1): 67, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443377

RESUMEN

High-performance active terahertz modulators as the indispensable core components are of great importance for the next generation communication technology. However, they currently suffer from the tradeoff between modulation depth and speed. Here, we introduce two-dimensional (2D) tellurium (Te) nanofilms with the unique structure as a new class of optically controlled terahertz modulators and demonstrate their integrated heterojunctions can successfully improve the device performances to the optimal and applicable levels among the existing all-2D broadband modulators. Further photoresponse measurements confirm the significant impact of the stacking order. We first clarify the direction of the substrate-induced electric field through first-principles calculations and uncover the unusual interaction mechanism in the photoexcited carrier dynamics associated with the charge transfer and interlayer exciton recombination. This advances the fundamental and applicative research of Te nanomaterials in high-performance terahertz optoelectronics.

16.
Materials (Basel) ; 17(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38473461

RESUMEN

A facile method for the immobilization of ß-cyclodextrin on polysulfone membranes with the aim of selectively adsorbing low-density lipoprotein (LDL) was established, which is based on the self-assembly of dopamine on the membrane followed by the Schiff base reaction with mono-(6-ethanediamine-6-deoxy)-ß-cyclodextrin. The surface modification processes were validated using X-ray photoelectron spectroscopy and attenuated total reflectance Fourier-transform infrared spectroscopy. Surface wettability and surface charge of the membranes were investigated through the water contact angle and zeta potential analysis. The cyclodextrin-modified polysulfone membrane (PSF-CD) showed good resistance to protein solutions, as shown by the measurement of BSA adsorption. The assessment of BSA adsorption revealed that the cyclodextrin-modified polysulfone membrane (PSF-CD) exhibited excellent resistance to protein solutions. To investigate the adsorption and desorption behaviors of the membranes in single-protein or binary-protein solutions, an enzyme-linked immunosorbent assay was employed. The results revealed that the PSF-CD possessed remarkable adsorption capacity and higher affinity for LDL in both single-protein and binary-protein solutions, rendering it a suitable material for LDL apheresis.

17.
World J Microbiol Biotechnol ; 40(5): 143, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38530548

RESUMEN

Polystyrene (PS) is frequently used in the plastics industry. However, its structural stability and difficulty to break down lead to an abundance of plastic waste in the environment, resulting in micro-nano plastics (MNPs). As MNPs are severe hazards to both human and environmental health, it is crucial to develop innovative treatment technologies to degrade plastic waste. The biodegradation of plastics by insect gut microorganisms has gained attention as it is environmentally friendly, efficient, and safe. However, our knowledge of the biodegradation of PS is still limited. This review summarizes recent research advances on PS biodegradation by gut microorganisms/enzymes from insect larvae of different species, and schematic pathways of the degradation process are discussed in depth. Additionally, the prospect of using modern biotechnology, such as genetic engineering and systems biology, to identify novel PS-degrading microbes/functional genes/enzymes and to realize new strategies for PS biodegradation is highlighted. Challenges and limitations faced by the application of genetically engineered microorganisms (GEMs) and multiomics technologies in the field of plastic pollution bioremediation are also discussed. This review encourages the further exploration of the biodegradation of PS by insect gut microbes/enzymes, offering a cutting-edge perspective to identify PS biodegradation pathways and create effective biodegradation strategies.


Asunto(s)
Microbioma Gastrointestinal , Poliestirenos , Animales , Humanos , Poliestirenos/metabolismo , Plásticos , Biodegradación Ambiental , Insectos
18.
Environ Sci Technol ; 58(15): 6804-6813, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38512799

RESUMEN

The pervasive contamination of novel brominated flame retardants (NBFRs) in remote polar ecosystems has attracted great attention in recent research. However, understanding regarding the trophic transfer behavior of NBFRs in the Arctic and Antarctic marine food webs is limited. In this study, we examined the occurrence and trophodynamics of NBFRs in polar benthic marine sediment and food webs collected from areas around the Chinese Arctic Yellow River Station (n = 57) and Antarctic Great Wall Station (n = 94). ∑7NBFR concentrations were in the range of 1.27-7.47 ng/g lipid weight (lw) and 0.09-1.56 ng/g lw in the Arctic and Antarctic marine biota, respectively, among which decabromodiphenyl ethane (DBDPE) was the predominant compound in all sample types. The biota-sediment bioaccumulation factors (g total organic carbon/g lipid) of NBFRs in the Arctic (0.85-3.40) were 4-fold higher than those in the Antarctica (0.13-0.61). Trophic magnification factors (TMFs) and their 95% confidence interval (95% CI) of individual NBFRs ranged from 0.43 (95% CI: 0.32, 0.60) to 1.32 (0.92, 1.89) and from 0.34 (0.24, 0.49) to 0.92 (0.56, 1.51) in the Arctic and Antarctic marine food webs, respectively. The TMFs of most congeners were significantly lower than 1, indicating a trophic dilution potential. This is one of the very few investigations on the trophic transfer of NBFRs in remote Arctic and Antarctic marine ecosystems, which provides a basis for exploring the ecological risks of NBFRs in polar regions.


Asunto(s)
Retardadores de Llama , Regiones Antárticas , Retardadores de Llama/análisis , Cadena Alimentaria , Ecosistema , Bioacumulación , Regiones Árticas , Monitoreo del Ambiente , Lípidos , Éteres Difenilos Halogenados/análisis
19.
Artículo en Inglés | MEDLINE | ID: mdl-38536957

RESUMEN

O3-type layered oxide cathodes (NaxTMO2) for sodium-ion batteries (SIBs) have attracted significant attention as one of the most promising potential candidates for practical energy storage applications. The poor Na+ diffusion kinetics is, however, one of the major obstacles to advancing large-scale practical application. Herein, we report bismuth-doped O3-NaNi0.5Mn0.5O2 (NMB) microspheres consisting of unique primary nanoplatelets with the radially oriented {010} active lattice facets. The NMB combines the advantages of the oriented and exposed electrochemical active planes for direct paths of Na+ diffusion, and the thick primary nanoplatelets for less surface parasitic reactions with the electrolyte. Consequently, the NMB cathode exhibits a long-term stability with an excellent capacity retention of 72.5% at 1C after 300 cycles and an enhanced rate capability at a 0.1C to 10C rate (1C = 240 mA g-1). Furthermore, the enhancement is elucidated by the small volume change, thin cathode-electrolyte-interphase (CEI) layer, and rapid Na+ diffusion kinetics. In particular, the radial orientation-based Bi-doping strategy is demonstrated to be effective at boosting electrochemical performance in other layered oxides (such as Bi-doped NaNi0.45Mn0.45Ti0.1O2 and NaNi1/3Fe1/3Mn1/3O2). The results provide a promising strategy of utilizing the advantages of the oriented active facets of primary platelets and secondary particles to develop high-rate layered oxide cathodes for SIBs.

20.
Nat Commun ; 15(1): 2252, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480744

RESUMEN

Zero thermal expansion (ZTE) alloys with high mechanical response are crucial for their practical usage. Yet, unifying the ZTE behavior and mechanical response in one material is a grand obstacle, especially in multicomponent ZTE alloys. Herein, we report a near isotropic zero thermal expansion (αl = 1.10 × 10-6 K-1, 260-310 K) in the natural heterogeneous LaFe54Co3.5Si3.35 alloy, which exhibits a super-high toughness of 277.8 ± 14.7 J cm-3. Chemical partition, in the dual-phase structure, assumes the role of not only modulating thermal expansion through magnetic interaction but also enhancing mechanical properties via interface bonding. The comprehensive analysis reveals that the hierarchically synergistic enhancement among lattice, phase interface, and heterogeneous structure is significant for strong toughness. Our findings pave the way to tailor thermal expansion and obtain prominent mechanical properties in multicomponent alloys, which is essential to ultra-stable functional materials.

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