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1.
Natl Sci Rev ; 11(7): nwae190, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38938275

RESUMEN

Heterogeneous catalysis promises to accelerate sulfur-involved conversion reactions in lithium-sulfur batteries. Solid-state Li2S dissociation remains as the rate-limiting step because of the weakly matched solid-solid electrocatalysis interfaces. We propose an electrochemically molecular-imprinting strategy to have a metal sulfide (MS) catalyst with imprinted defects in positions from which the pre-implanted Li2S has been electrochemically removed. Such tailor-made defects enable the catalyst to bind exclusively to Li atoms in Li2S reactant and elongate the Li-S bond, thus decreasing the reaction energy barrier during charging. The imprinted Ni3S2 catalyst shows the best activity due to the highest defect concentration among the MS catalysts examined. The Li2S oxidation potential is substantially reduced to 2.34 V from 2.96 V for the counterpart free of imprinted vacancies, and an Ah-level pouch cell is realized with excellent cycling performance. With a lean electrolyte/sulfur ratio of 1.80 µL mgS -1, the cell achieves a benchmarkedly high energy density beyond 500 Wh kg-1.

2.
Fitoterapia ; : 106094, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38936674

RESUMEN

In the present study, six new compounds namely, picralactones CH (1-6) along with nine known compounds (7-15) were isolated from the branches and leaves of Picrasma chinese P.Y. Chen. Their structures were determined with the help of spectroscopic techniques such as NMR, HR-ESI-MS, UV, IR and CD. Cytotoxicity of all compounds was evaluated against MDA-MB-231, SW-620 and HepG2 human cancer cell lines. Compound 4 showed cytotoxic activities.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38936813

RESUMEN

The unsatisfactory oxygen reduction reaction (ORR) kinetics caused by the inherent lean-oxygen marine environment brings low power density for metal-dissolved oxygen seawater batteries (SWBs). In this study, we propose a seawater/electrode interfacial engineering strategy by constructing a hydrophobic coating to realize enhanced mass transfer of dissolved oxygen for the fully immersed cathode of SWBs. Accumulation of dissolved oxygen from seawater to the catalyst is particularly beneficial for improving the ORR performance under lean-oxygen conditions. As a result, SWB assembled with a hydrophobic cathode achieved a power density of up to 2.32 mW cm-2 and sustained discharge at 1.3 V for 250 h. Remarkably, even in environments with an oxygen concentration of 4 mg L-1, it can operate at a voltage approximately 100 mV higher than that of an unmodified SWB. The introduction of a hydrophobic interface enhances the discharge voltage and power of SWBs by improving interfacial oxygen mass transfer, providing new insights into improving the underwater ORR performance for practical SWBs.

4.
Adv Mater ; : e2406071, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899999

RESUMEN

Developing hydrophobic interface has proven effective in addressing dendrite growth and side reactions during zinc (Zn) plating in aqueous Zn batteries. However, this solution inadvertently impedes the solvation of Zn2+ with H2O and subsequent ionic transport during Zn stripping, leading to insufficient reversibility. Herein, an adaptive hydrophobic interface that can be switched "on" and "off" by ionic valves to accommodate the varying demands for interfacial H2O during both the Zn plating and stripping processes, is proposed. This concept is validated using octyltrimethyl ammonium bromide (C8TAB) as the ionic valve, which can initiatively establish and remove a hydrophobic interface in response to distinct electric-field directions during Zn plating and stripping, respectively. Consequently, the Zn anode exhibits an extended cycling life of over 2500 h with a high Coulombic efficiency of ≈99.8%. The full cells also show impressive capacity retention of over 85% after 1 000 cycles at 5 A g-1. These findings provide a new insight into interface design for aqueous metal batteries.

5.
Adv Sci (Weinh) ; : e2402497, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884340

RESUMEN

Catalysis is crucial to improve redox kinetics in lithium-sulfur (Li-S) batteries. However, conventional catalysts that consist of a single metal element are incapable of accelerating stepwise sulfur redox reactions which involve 16-electron transfer and multiple Li2Sn (n = 2-8) intermediate species. To enable fast kinetics of Li-S batteries, it is proposed to use high-entropy alloy (HEA) nanocatalysts, which are demonstrated effective to adsorb lithium polysulfides and accelerate their redox kinetics. The incorporation of multiple elements (Co, Ni, Fe, Pd, and V) within HEAs greatly enhances the catalytically active sites, which not only improves the rate capability, but also elevates the cycling stability of the assembled batteries. Consequently, HEA-catalyzed Li-S batteries achieve a high capacity up to 1364 mAh g-1 at 0.1 C and experience only a slight capacity fading rate of 0.054% per cycle over 1000 cycles at 2 C, while the assembled pouch cell achieves a high specific capacity of 1192 mAh g-1. The superior performance of Li-S batteries demonstrates the effectiveness of the HEA catalysts with maximized synergistic effect for accelerating S conversion reactions, which opens a way to catalytically improving stepwise electrochemical conversion reactions.

6.
Brain Behav Immun ; 120: 352-359, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38897329

RESUMEN

BACKGROUND: Experimental and cross-sectional evidence has suggested a potential role of infection in the ethology of Parkinson's disease (PD). We aim to examine the longitudinal association of infections with the incidence of PD and to explore whether the increased risk is limited to specific infection type rather than infection burden. METHODS: Based on the UK Biobank, hospital-treated infectious diseases and incident PD were ascertained through record linkage to national hospital inpatient registers. Infection burden was defined as the sum of the number of infection episodes over time and the number of co-occurring infections. The polygenic risk score (PRS) for PD was calculated. The genome-wide association studies (GWAS) used in two-sample Mendelian Randomization (MR) were obtained from observational cohort participants of mostly European ancestry. RESULTS: Hospital-treated infectious diseases were associated with an increased risk of PD (adjusted HR [aHR] 1.35 [95 % CI 1.20-1.52]). This relationship persisted when analyzing new PD cases occurring more than 10 years post-infection (aHR 1.22 [95 % CI 1.04-1.43]). The greatest PD risk was observed in neurological/eye infection (aHR 1.72 [95 % CI 1.32-2.34]), with lower respiratory tract infection (aHR 1.43 [95 % CI 1.02-1.99]) ranked the second. A dose-response association was observed between infection burden and PD risk within each PD-PRS tertile (p-trend < 0.001). Multivariable MR showed that bacterial and viral infections increase the PD risk. CONCLUSIONS: Both observational and genetic analysis suggested a causal association between infections and the risk of developing PD. A dose-response relationship between infection burden and incident PD was revealed.

7.
Diabetes Metab Syndr ; 18(6): 103063, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38917709

RESUMEN

BACKGROUND: The longitudinal association between infectious diseases and the risk of type 2 diabetes (T2D) remains unclear. METHODS: Based on the UK Biobank, the prospective cohort study included a total of 396,080 participants without diabetes at baseline. We determined the types and sites of infectious diseases and incident T2D using the International Classification of Diseases 10th Revision codes (ICD-10). Time-varying Cox proportional hazard model was used to assess the association. Infection burden was defined as the number of infection episodes over time and the number of co-occurring infections. Genetic risk score (GRS) for T2D consisted of 424 single nucleotide polymorphisms. RESULTS: During a median of 9.04 [IQR, 8.3-9.7] years of follow-up, hospital-treated infectious diseases were associated with a greater risk of T2D (adjusted HR [aHR] 1.54 [95 % CI 1.46-1.61]), with risk difference per 10,000 individuals equal to 154.1 [95 % CI 140.7-168.2]. The heightened risk persisted after 5 years following the index infection. Bacterial infection with sepsis had the strongest risk of T2D (aHR 2.95 [95 % CI 2.53-3.44]) among different infection types. For site-specific analysis, bloodstream infections posed the greatest risk (3.01 [95 % CI 2.60-3.48]). A dose-response association was observed between infection burden and T2D risk within each GRS tertile (p-trend <0.001). High genetic risk and infection synergistically increased the T2D risk. CONCLUSION: Infectious diseases were associated with an increased risk of subsequent T2D. The risk showed specificity according to types, sites, severity of infection and the period since infection occurred. A potential accumulative effect of infection was revealed.

8.
J Asian Nat Prod Res ; 26(7): 803-811, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38721701

RESUMEN

Two new triterpenes mayteneri A (1), mayteneri B (2), and seven known compounds (3-9) were isolated from stems of Maytenus hookeri Loes. The chemical structures of compounds 1 and 2 were established by 1D, 2D NMR, HRESIMS analysis, and calculating electronic circular dichroism (ECD). The structures of known compounds 3-9 were determined by comparison of their spectral with those reported. Compounds 4-7 showed significant inhibitory activity for NLRP3 inflammasome, with the IC50 values of 2.36-3.44 µM.


Asunto(s)
Maytenus , Ácido Oleanólico , Estructura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Maytenus/química , Triterpenos/química , Triterpenos/farmacología , Triterpenos/aislamiento & purificación , Tallos de la Planta/química , Animales , Ratones , Inflamasomas/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores
9.
J Immunol Res ; 2024: 2765001, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38774603

RESUMEN

ß-Glucan is the main component of the cell wall of pathogen-associated molecular patterns (PAMPs) including various yeast, fungi, or certain bacteria. Previous reports demonstrated that ß-glucan was widely investigated as a potent immunomodulators to stimulate innate and adaptive immune responses, which indicated that it could be recommended as an effective adjuvant in immunotherapy. However, the detailed effects of ß-glucan on neonatal immunity are still largely unknown. Here, we found that ß-glucan did not affect the frequencies and numbers of myeloid cells in the spleen and bone marrow from neonates. Functional assay revealed that ß-glucan from neonates compromised the immunosuppressive function of immature myeloid cells, which were myeloid-derived suppressor cells (MDSCs). Flow cytometry or gene expression analysis revealed that ß-glucan-derived polymorphonuclear (PMN)-MDSCs produced lower level of reactive oxygen species (ROS) and arginase-1 (Arg1) in neonatal mice. Furthermore, ß-glucan administration significantly decreased the frequency and ROS level of PMN-MDSCs in vitro. These observations suggest that ß-glucan facilitates the maturation of myeloid cells in early life, which may contribute to its beneficial effects against immune disorders later in life.


Asunto(s)
Animales Recién Nacidos , Arginasa , Células Supresoras de Origen Mieloide , Especies Reactivas de Oxígeno , beta-Glucanos , Animales , Ratones , Arginasa/metabolismo , beta-Glucanos/farmacología , Ratones Endogámicos C57BL , Células Mieloides/metabolismo , Células Mieloides/inmunología , Células Mieloides/efectos de los fármacos , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/metabolismo , Células Supresoras de Origen Mieloide/efectos de los fármacos , Neutrófilos/inmunología , Neutrófilos/metabolismo , Neutrófilos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Bazo/inmunología , Bazo/metabolismo , Bazo/citología
10.
J Immunol ; 213(2): 170-186, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38819229

RESUMEN

Myeloid-derived suppressor cells (MDSCs), the negative immune regulators, have been demonstrated to be involved in immune responses to a variety of pathological conditions, such as tumors, chronic inflammation, and infectious diseases. However, the roles and mechanisms underlying the expansion of MDSCs in malaria remain unclear. In this study, the phenotypic and functional characteristics of splenic MDSCs during Plasmodium yoelii NSM infection are described. Furthermore, we provide compelling evidence that the sera from P. yoelii-infected C57BL/6 mice containing excess IL-6 and granulocyte-macrophage colony-stimulating factor promote the accumulation of MDSCs by inducing Bcl2 expression. Serum-induced MDSCs exert more potent suppressive effects on T cell responses than control MDSCs within both in vivo P. yoelii infection and in vitro serum-treated bone marrow cells experiments. Serum treatment increases the MDSC inhibitory effect, which is dependent on Arg1 expression. Moreover, mechanistic studies reveal that the serum effects are mediated by JAK/STAT3 signaling. By inhibiting STAT3 phosphorylation with the JAK inhibitor JSI-124, effects of serum on MDSCs are almost eliminated. In vivo depletion of MDSCs with anti-Gr-1 or 5-fluorouracil significantly reduces the parasitemia and promotes Th1 immune response in P. yoelii-infected C57BL/6 mice by upregulating IFN-γ expression. In summary, this study indicates that P. yoelii infection facilitates the accumulation and function of MDSCs by upregulating the expression of Bcl2 and Arg1 via JAK/STAT3 signaling pathway in vivo and in vitro. Manipulating the JAK/STAT3 signaling pathway or depleting MDSCs could be promising therapeutic interventions to treat malaria.


Asunto(s)
Quinasas Janus , Malaria , Ratones Endogámicos C57BL , Células Supresoras de Origen Mieloide , Plasmodium yoelii , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Plasmodium yoelii/inmunología , Malaria/inmunología , Células Supresoras de Origen Mieloide/inmunología , Ratones , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/inmunología , Quinasas Janus/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Arginasa/metabolismo , Interleucina-6/metabolismo , Interleucina-6/inmunología , Femenino
11.
Plant Signal Behav ; 19(1): 2349868, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38743594

RESUMEN

The purpose of this study was to analyze the role of transcription factor in Desmodium styracifolium, proving that the DsWRKY6 transcription factor was related to the plant phenotypes of Desmodium styracifolium - cv. 'GuangYaoDa1' and it could be used in molecular-assisted breeding. 'GuangYaoDa1' was used as the material and its DNA was the template to clone DsWRKY6, the transgenic Arabidopsis thaliana line was constructed by agrobacterium tumefaciens­mediated transformation. Transgenic Arabidopsis thaliana was cultivated to study phenotype and physiological and biochemical indexes. Phenotypic observation showed that DsWRKY6 transgenic Arabidopsis thaliana had a faster growth rate while compared with the control group, they had longer lengths of main stem, lateral branches of cauline leaves, and root, but a lower number of cauline leaves and lateral branches of cauline leaves. And it also showed that their flowering and fruiting periods were advanced. The results of physiological and biochemical indexes showed that the relative expressions of DsWRKY6 increased and the abscisic acid content significantly increased in DsWRKY6 transgenic Arabidopsis thaliana compared with the control group. According to the above results, DsWRKY6 could regulate the advancing of flowering and fruiting periods caused by the improvement of abscisic acid content, and expression of the DsWRKY6 transcription factor might be the cause of the upright growth of 'GuangYaoDa1'.


Asunto(s)
Clonación Molecular , Genes de Plantas , Factores de Transcripción , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Regulación de la Expresión Génica de las Plantas , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética
12.
J Am Chem Soc ; 146(22): 15209-15218, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38775661

RESUMEN

Solid electrolyte interphases (SEIs) are sought to protect high-capacity anodes, which suffer from severe volume changes and fast degradations. The previously proposed effective SEIs were of high strength yet abhesive, inducing a yolk-shell structure to decouple the rigid SEI from the anode for accommodating the volume change. Ambivalently, the interfacial void-evolved electro-chemo-mechanical vulnerabilities become inherent defects. Here, we establish a new rationale for SEIs that resilience and adhesivity are both requirements and pioneer a design of a resilient yet adhesive SEI (re-ad-SEI), integrated into a conjugated surface bilayer structure. The re-ad-SEI and its protected particles exhibit excellent stability almost free from the thickening of SEI and the particle pulverization during cycling. More promisingly, the dynamically bonded intact SEI-anode interfaces enable a high-efficiency ion transport and provide a unique mechanical confinement effect for structural integrity of anodes. The high Coulombic efficiency (>99.8%), excellent cycling stability (500 cycles), and superior rate performance have been demonstrated in microsized Si-based anodes.

13.
Adv Sci (Weinh) ; : e2403043, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38810136

RESUMEN

The optoelectronic resistive random-access memory (RRAM) with the integrated function of perception, storage and intrinsic randomness displays promising applications in the hardware level in-sensor image cryptography. In this work, 2D hexagonal boron nitride based optoelectronic RRAM is fabricated with semitransparent noble metal (Ag or Au) as top electrodes, which can simultaneous capture color image and generate physically unclonable function (PUF) key for in-sensor color image cryptography. Surface plasmons of noble metals enable the strong light absorption to realize an efficient modulation of filament growth at nanoscale. Resistive switching curves show that the optical stimuli can impede the filament aggregation and promote the filament annihilation, which originates from photothermal effects and photogenerated hot electrons in localized surface plasmon resonance of noble metals. By selecting noble metals, the optoelectronic RRAM array can respond to distinct wavelengths and mimic the biological dichromatic cone cells to perform the color perception. Due to the intrinsic and high-quality randomness, the optoelectronic RRAM can produce a PUF key in every exposure cycle, which can be applied in the reconfigurable cryptography. The findings demonstrate an effective strategy to build optoelectronic RRAM for in-sensor color image cryptography applications.

14.
Nat Commun ; 15(1): 3892, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719816

RESUMEN

As a sustainable alternative to fossil fuel-based manufacture of bulk oxygenates, electrochemical synthesis using CO and H2O as raw materials at ambient conditions offers immense appeal. However, the upscaling of the electrosynthesis of oxygenates encounters kinetic bottlenecks arising from the competing hydrogen evolution reaction with the selective production of ethylene. Herein, a catalytic relay system that can perform in tandem CO capture, activation, intermediate transfer and enrichment on a Cu-Ag composite catalyst is used for attaining high yield CO-to-oxygenates electrosynthesis at high current densities. The composite catalyst Cu/30Ag (molar ratio of Cu to Ag is 7:3) enables high efficiency CO-to-oxygenates conversion, attaining a maximum partial current density for oxygenates of 800 mA cm-2 at an applied current density of 1200 mA cm-2, and with 67 % selectivity. The ability to finely control the production of ethylene and oxygenates highlights the principle of efficient catalyst design based on the relay mechanism.

15.
Adv Mater ; 36(27): e2400937, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38634714

RESUMEN

Alkali metal-air batteries (AMABs) promise ultrahigh gravimetric energy densities, while the inherent poor cycle stability hinders their practical application. To address this challenge, most previous efforts are devoted to advancing the air cathodes with high electrocatalytic activity. Recent studies have underlined the solid-liquid-gas triple-phase interface around the anode can play far more significant roles than previously acknowledged by the scientific community. Besides the bottlenecks of uncontrollable dendrite growth and gas evolution in conventional alkali metal batteries, the corrosive gases, intermediate oxygen species, and redox mediators in AMABs cause more severe anode corrosion and structural collapse, posing greater challenges to the stabilization of the anode triple-phase interface. This work aims to provide a timely perspective on the anode interface engineering for durable AMABs. Taking the Li-air battery as a typical example, this critical review shows the latest developed anode stabilization strategies, including formulating electrolytes to build protective interphases, fabricating advanced anodes to improve their anti-corrosion capability, and designing functional separator to shield the corrosive species. Finally, the remaining scientific and technical issues from the prospects of anode interface engineering are highlighted, particularly materials system engineering, for the practical use of AMABs.

16.
Nat Commun ; 15(1): 3497, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664385

RESUMEN

Hard carbons are emerging as the most viable anodes to support the commercialization of sodium-ion (Na-ion) batteries due to their competitive performance. However, the hard carbon anode suffers from low initial Coulombic efficiency (ICE), and the ambiguous Na-ion (Na+) storage mechanism and interfacial chemistry fail to give a reasonable interpretation. Here, we have identified the time-dependent ion pre-desolvation on the nanopore of hard carbons, which significantly affects the Na+ storage efficiency by altering the solvation structure of electrolytes. Consummating the pre-desolvation by extending the aging time, generates a highly aggregated electrolyte configuration inside the nanopore, resulting in negligible reductive decomposition of electrolytes. When applying the above insights, the hard carbon anodes achieve a high average ICE of 98.21% in the absence of any Na supplementation techniques. Therefore, the negative-to-positive capacity ratio can be reduced to 1.02 for full cells, which enables an improved energy density. The insight into hard carbons and related interphases may be extended to other battery systems and support the continued development of battery technology.

17.
Huan Jing Ke Xue ; 45(5): 2651-2664, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629529

RESUMEN

In order to enhance the support for groundwater development and utilization, as well as pollution control and prevention in Fengtai District, Beijing, a comprehensive study was conducted based on long-term monitoring data of shallow groundwater in the eastern area of Yongding River during the dry season. The mathematical statistics, Piper diagram, Gibbs diagram, and ion ratio analysis and other methods were employed to explore the pattern of groundwater hydrochemical evolution, the formation mechanism, and sources of pollution in Fengtai District. The findings were as follows:① Overall, the current groundwater quality in the study area was poor. The average concentration of each index in groundwater increased and then decreased from 1976 to the present. The pollution range of Cl-, SO42-, and TH generally expanded, whereas the pollution range of TDS and NO3- expanded before 2005 and then decreased with 2005 as the turning point. ② The hydrochemical types of groundwater samples displayed a complex regional variation each year, as well as along the groundwater direction. The dominant anion in groundwater was HCO3-, and the dominant cation was Ca2+ each year. The number of groundwater hydrochemical types in 1976 was 8, in which the predominant type was HCO3·SO4-Ca·Mg·Na, accounting for 40%. However, the number of groundwater hydrochemical types in 2021 was 17, in which the predominant type was HCO3·Cl·SO4-Ca·Na·Mg, accounting for 23.88%. The groundwater hydrochemical type showed a complex trend within the region and upstream along the flow direction each year, whereas the migration characteristics of groundwater samples, as depicted on the Piper diagram, indicated that the hydrochemical components of groundwater were significantly affected by human activities during its evolution. ③ The groundwater chemistry in the study area was influenced by both rock weathering and evaporative crystallization processes, with evaporation playing a major role. The alternation of groundwater cations was relatively weak, and the dissolution of carbonate minerals served as the primary source of Ca2+ and Mg2+. ④ The ion ratio analysis suggested that exogenous sources, mainly agricultural activities and urban sewage, contributed to the input of NO3- and Cl-. The pollution impact from agricultural activities was significant before 2005, which aligned with the historical presence of numerous seepage pits, seepage wells, and direct discharge of industrial and domestic sewage for irrigation purposes in the study area. These activities were closely associated with the high levels of pollution. However, pollution input from agricultural activities notably decreased in 2021, likely due to the effective implementation of water environmental protection programs and action plans in recent years.

18.
Artículo en Inglés | MEDLINE | ID: mdl-38554119

RESUMEN

OBJECTIVES: Although research has shown that the replay of encoding-specific gaze patterns during retrieval, known as gaze reinstatement, facilitates memory retrieval, little is known about whether it differentially associates with the negativity preference in memory (defined as enhanced memory for negative stimuli relative to neutral stimuli in this study) among younger and older adults. The present study aims to address this research gap. METHODS: A total of 33 older adults (16 women; aged 58-69 years, M = 63.48, SD = 2.98) and 36 younger adults (10 women; aged 18-26 years, M = 20.39, SD = 1.57) completed a remember/know recognition memory task involving negative and neutral pictures. Their eye movements were tracked during both the memory encoding and retrieval phases. RESULTS: Younger and older adults had better memory for negative than neutral pictures. Older adults exhibited significantly stronger gaze reinstatement for negative than neutral stimuli, while this difference was nonsignificant in younger adults. Moreover, gaze reinstatement is positively linked to memory performance in both age groups. DISCUSSION: The results suggest that gaze reinstatement may play age-differential roles in the negativity preference of memory. Negative valence may enhance gaze reinstatement, which improves subsequent recognition memory, particularly among older adults. The finding contributes to a better understanding of the mechanisms underlying the negative preference for memory in different age groups.


Asunto(s)
Fijación Ocular , Reconocimiento en Psicología , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Reconocimiento en Psicología/fisiología , Adulto , Adulto Joven , Fijación Ocular/fisiología , Adolescente , Factores de Edad , Recuerdo Mental/fisiología , Envejecimiento/psicología , Envejecimiento/fisiología
19.
Langmuir ; 40(20): 10460-10467, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38441484

RESUMEN

Establishing low-resistance ohmic contact is critical for developing electronic devices based on traditional silicon and new low-dimensional materials. Due to unprecedented electronic and mechanical properties, the one-dimensional carbon nanotubes (CNTs) have been used as source/drain, gate, or tunnel to fabricate transistors. However, the mechanism causing low-resistance ohmic contact is not clear yet. Here, the hybrid atomic force microscopy-scanning electron microscopy (AFM-SEM) instrument was developed to establish lower-resistance ohmic contact between a radial compressed deformed multiwalled CNT bundle and high work function metal (platinum and gold). The radial compression structure under strong van der Waals attraction was in situ characterized through the SEM image to obtain the diameter and width and through AFM to get height and to perform nanoindentation, indicating that Pt has the smaller radial compression deformation. Molecular dynamics simulations exhibit that compared to Pt, a wider ribbon-like graphene layer formed when the radial compressed CNTs contacted with Au. The bond forming and electron orbital overlapping between C atoms of deformed CNTs and the high work function metal atom is beneficial for good electrical contact.

20.
Arch Microbiol ; 206(3): 110, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38369673

RESUMEN

A Gram-positive, aerobic, non-motile, irregular short rod, nonspore-forming actinobacterial strain, designated GX14115T, was isolated from fish intestine in Beihai City, Guangxi, China and subjected to a taxonomic polyphasic investigation. Colonies were yellow‒green, circular, smooth, central bulge, convex, opaque and 2.0-3.0 mm in diameter after growth on 2216E medium at 30 °C for 72 h. Growth occurred at 4-45 °C (optimum 30 °C), at pH 4.5-10.0 (optimum pH 7.5) and in the presence of 0-12% NaCl (w/v) (optimum 3.5%). Chemotaxonomic analysis showed that the main menaquinone of strain GX14115T was MK-7. The major cellular fatty acids were anteiso-C15:0 (44.8%), anteiso-C17:0 (20.5%), and iso-C15:0 (16%). The whole-cell sugars were galactose and xylose. The peptidoglycan type was L-Lys-Gly-D-Asp, and the polar lipids were phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), one unknown phospholipid (UP), and one unknown glycolipid (UG). The DNA G + C content of the type of strain was 69.5 mol%. The 16S rRNA gene sequence analysis revealed that strain GX14115T is affiliated with the genus Nesterenkonia and is closely related to Nesterenkonia sandarakina YIM 70009T (96.5%) and Nesterenkonia lutea YIM 70081T (96.8%). The calculated results indicated that the average nucleotide identity (ANI) values of GX14115T were 74.49-74.78%, to the two aforementioned type strains, and the digital DNA-DNA hybridization (dDDH) values were 20.1-20.7%. Strain GX14115T was proposed as a novel species of the genus Nesterenkonia by the physiological, chemotaxonomic, and phylogenetic data, for whose the name is Nesterenkonia marinintestina sp. nov. The type of strain is GX14115T (= MCCC 1K06658T = KCTC 49495T).


Asunto(s)
Ácidos Grasos , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , China , Ácidos Grasos/análisis , Fosfolípidos/análisis , Análisis de Secuencia de ADN , Técnicas de Tipificación Bacteriana
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