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1.
Proc Natl Acad Sci U S A ; 121(5): e2313096121, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38261613

RESUMEN

Ether solvents are suitable for formulating solid-electrolyte interphase (SEI)-less ion-solvent cointercalation electrolytes in graphite for Na-ion and K-ion batteries. However, ether-based electrolytes have been historically perceived to cause exfoliation of graphite and cell failure in Li-ion batteries. In this study, we develop strategies to achieve reversible Li-solvent cointercalation in graphite through combining appropriate Li salts and ether solvents. Specifically, we design 1M LiBF4 1,2-dimethoxyethane (G1), which enables natural graphite to deliver ~91% initial Coulombic efficiency and >88% capacity retention after 400 cycles. We captured the spatial distribution of LiF at various length scales and quantified its heterogeneity. The electrolyte shows self-terminated reactivity on graphite edge planes and results in a grainy, fluorinated pseudo-SEI. The molecular origin of the pseudo-SEI is elucidated by ab initio molecular dynamics (AIMD) simulations. The operando synchrotron analyses further demonstrate the reversible and monotonous phase transformation of cointercalated graphite. Our findings demonstrate the feasibility of Li cointercalation chemistry in graphite for extreme-condition batteries. The work also paves the foundation for understanding and modulating the interphase generated by ether electrolytes in a broad range of electrodes and batteries.

2.
Nano Lett ; 24(7): 2345-2351, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38334460

RESUMEN

Nonvolatile multistate manipulation of two-dimensional (2D) magnetic materials holds promise for low dissipation, highly integrated, and versatile spintronic devices. Here, utilizing density functional theory calculations and Monte Carlo simulations, we report the realization of nonvolatile and multistate control of topological magnetism in monolayer CrI3 by constructing multiferroic heterojunctions with quadruple-well ferroelectric (FE) materials. The Pt2Sn2Te6/CrI3 heterojunction exhibits multiple magnetic phases upon modulating FE polarization states of FE layers and interlayer sliding. These magnetic phases include Bloch-type skyrmions and ferromagnetism, as well as a newly discovered topological magnetic structure. We reveal that the Dzyaloshinskii-Moriya interaction (DMI) induced by interfacial coupling plays a crucial role in magnetic skyrmion manipulation, which aligns with the Fert-Levy mechanism. Moreover, a regular magnetic skyrmion lattice survives when removing a magnetic field, demonstrating its robustness. The work sheds light on an effective approach to nonvolatile and multistate control of 2D magnetic materials.

3.
J Biol Chem ; 299(5): 104686, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37031820

RESUMEN

Dry age-related macular degeneration (AMD) and recessive Stargardt's disease (STGD1) lead to irreversible blindness in humans. The accumulation of all-trans-retinal (atRAL) induced by chaos in visual cycle is closely associated with retinal atrophy in dry AMD and STGD1 but its critical downstream signaling molecules remain ambiguous. Here, we reported that activation of eukaryotic translation initiation factor 2α (eIF2α) by atRAL promoted retinal degeneration and photoreceptor loss through activating c-Jun N-terminal kinase (JNK) signaling-dependent apoptosis and gasdermin E (GSDME)-mediated pyroptosis. We determined that eIF2α activation by atRAL in photoreceptor cells resulted from endoplasmic reticulum homeostasis disruption caused at least in part by reactive oxygen species production, and it activated JNK signaling independent of and dependent on activating transcription factor 4 and the activating transcription factor 4/transcription factor C/EBP homologous protein (CHOP) axis. CHOP overexpression induced apoptosis of atRAL-loaded photoreceptor cells through activating JNK signaling rather than inhibiting the expression of antiapoptotic gene Bcl2. JNK activation by eIF2α facilitated photoreceptor cell apoptosis caused by atRAL via caspase-3 activation and DNA damage. Additionally, we demonstrated that eIF2α was activated in neural retina of light-exposed Abca4-/-Rdh8-/- mice, a model that shows severe defects in atRAL clearance and displays primary features of human dry AMD and STGD1. Of note, inhibition of eIF2α activation by salubrinal effectively ameliorated retinal degeneration and photoreceptor apoptosis in Abca4-/-Rdh8-/- mice upon light exposure. The results of this study suggest that eIF2α is an important target to develop drug therapies for the treatment of dry AMD and STGD1.


Asunto(s)
Factor 2 Eucariótico de Iniciación , Degeneración Retiniana , Retinaldehído , Enfermedad de Stargardt , Animales , Humanos , Ratones , Factor de Transcripción Activador 4/metabolismo , Apoptosis , Transportadoras de Casetes de Unión a ATP/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Degeneración Retiniana/genética , Degeneración Retiniana/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Retinaldehído/metabolismo , Enfermedad de Stargardt/metabolismo , Factor 2 Eucariótico de Iniciación/genética , Factor 2 Eucariótico de Iniciación/metabolismo
4.
BMC Genomics ; 25(1): 552, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38825700

RESUMEN

BACKGROUND: The disputed phylogenetic position of Aerides flabellata Rolfe ex Downie, due to morphological overlaps with related species, was investigated based on evidence of complete chloroplast (cp) genomes. The structural characterization of complete cp genomes of A. flabellata and A. rosea Lodd. ex Lindl. & Paxton were analyzed and compared with those of six related species in "Vanda-Aerides alliance" to provide genomic information on taxonomy and phylogeny. RESULTS: The cp genomes of A. flabellata and A. rosea exhibited conserved quadripartite structures, 148,145 bp and 147,925 bp in length, with similar GC content (36.7 ~ 36.8%). Gene annotations revealed 110 single-copy genes, 18 duplicated in inverted regions, and ten with introns. Comparative analysis across related species confirmed stable sequence identity and higher variation in single-copy regions. However, there are notable differences in the IR regions between two Aerides Lour. species and the other six related species. The phylogenetic analysis based on CDS from complete cp genomes indicated that Aerides species except A. flabellata formed a monophyletic clade nested in the subtribe Aeridinae, being a sister group to Renanthera Lour., consistent with previous studies. Meanwhile, a separate clade consisted of A. flabellata and six Vanda R. Br. species was formed, as a sister taxon to Holcoglossum Schltr. CONCLUSIONS: This research was the first report on the complete cp genomes of A. flabellata. The results provided insights into understanding of plastome evolution and phylogenetic relationships of Aerides. The phylogenetic analysis based on complete cp genomes showed that A. flabellata should be placed in Vanda rather than in Aerides.


Asunto(s)
Genoma del Cloroplasto , Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/clasificación , Composición de Base , Anotación de Secuencia Molecular
5.
J Am Chem Soc ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847794

RESUMEN

Traditional Li-ion intercalation chemistry into graphite anodes exclusively utilizes the cointercalation-free or cointercalation mechanism. The latter mechanism is based on ternary graphite intercalation compounds (t-GICs), where glyme solvents were explored and proved to deliver unsatisfactory cyclability in LIBs. Herein, we report a novel intercalation mechanism, that is, in situ synthesis of t-GIC in the tetrahydrofuran (THF) electrolyte via a spontaneous, controllable reaction between binary-GIC (b-GIC) and free THF molecules during initial graphite lithiation. The spontaneous transformation from b-GIC to t-GIC, which is different from conventional cointercalation chemistry, is characterized and quantified via operando synchrotron X-ray and electrochemical analyses. The resulting t-GIC chemistry obviates the necessity for complete Li-ion desolvation, facilitating rapid kinetics and synchronous charge/discharge of graphite particles, even under high current densities. Consequently, the graphite anode demonstrates unprecedented fast charging (1 min), dendrite-free low-temperature performance, and ultralong lifetimes exceeding 10 000 cycles. Full cells coupled with a layered cathode display remarkable cycling stability upon a 15 min charging and excellent rate capability even at -40 °C. Furthermore, our chemical strategies are shown to extend beyond Li-ion batteries to encompass Na-ion and K-ion batteries, underscoring their broad applicability. Our work contributes to the advancement of graphite intercalation chemistry and presents a low-cost, adaptable approach for achieving fast-charging and low-temperature batteries.

6.
Small ; 20(4): e2305903, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37715331

RESUMEN

Solar-driven interfacial evaporation is a potential water purification solution. Here, a novel regenerable hydrogel interfacial evaporator is designed with tunable water production. Such an evaporator is fabricated by readily mixing hydroxypropyl chitosan (HPCS) and dibenzaldehyde-functional poly(ethylene glycol) (DF-PEG) at ambient conditions. Dynamic Schiff base bonds bestow on the HPCS/DF-PEG hydrogel (HDH) evaporator self-adaptivity and pH responsiveness. The as-prepared HDH is enabled to spontaneously change shape to adapt to different molds, endowing the evaporator with adjustable evaporation area. The water production performance of the intelligent evaporator is first evaluated using tunable evaporation index (TEI, the tunable evaporated water mass per hour), which can be altered from 0 kg h-1 to 3.21 kg h-1 under one sun. Besides, the large-scale evaporator can be expediently fabricated by virtue of the self-adaptivity. Benefiting from the pH responsiveness, the HDH evaporator is successfully regenerated with the removal of organic dye by the liquefaction-dialysis-regeneration operations. Meanwhile, the re-created evaporator maintains the self-adaptive characteristic and almost constant water evaporation rate compared to that of the initial evaporator. Therefore, this distinctive concept provides a facile strategy to develop smart and recyclable solar-driven interfacial evaporators for flexible water purification.

7.
Hepatology ; 78(6): 1828-1842, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36804859

RESUMEN

BACKGROUND AIMS: SLC25A47 was initially identified as a mitochondrial HCC-downregulated carrier protein, but its physiological functions and transport substrates are unknown. We aimed to investigate the physiological role of SLC25A47 in hepatic metabolism. APPROACH RESULTS: In the treatment of hepatocytes with metformin, we found that metformin can transcriptionally activate the expression of Slc25a47 , which is required for AMP-activated protein kinase α (AMPKα) phosphorylation. Slc25a47 -deficient mice had increased hepatic lipid content, triglycerides, and cholesterol levels, and we found that Slc25a47 deficiency suppressed AMPKα phosphorylation and led to an increased accumulation of nuclear SREBPs, with elevated fatty acid and cholesterol biosynthetic activities. Conversely, when Slc25a47 was overexpressed in mouse liver, AMPKα was activated and resulted in the inhibition of lipogenesis. Moreover, using a diethylnitrosamine-induced mouse HCC model, we found that the deletion of Slc25a47 promoted HCC tumorigenesis and development through the activated mammalian target of rapamycin cascade. Employing homology modeling of SLC25A47 and virtual screening of the human metabolome database, we demonstrated that NAD + was an endogenous substrate for SLC25A47, and the activity of NAD + -dependent sirtuin 3 declined in Slc25a47 -deficient mice, followed by inactivation of AMPKα. CONCLUSIONS: Our findings reveal that SLC25A47, a hepatocyte-specific mitochondrial NAD + transporter, is one of the pharmacological targets of metformin and regulates lipid homeostasis through AMPKα, and may serve as a potential drug target for treating NAFLD and HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Metformina , Animales , Humanos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo de los Lípidos , NAD/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Metformina/farmacología , Carcinogénesis/metabolismo , Transformación Celular Neoplásica/metabolismo , Ácidos Grasos/metabolismo , Colesterol/metabolismo , Mamíferos/metabolismo
8.
Chem Rec ; 24(3): e202300361, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38362667

RESUMEN

Smart textile fabrics have been widely investigated and used in flexible wearable electronics because of their unique structure, flexibility and breathability, which are highly desirable with integrated multifunctionality. Recent years have witnessed the rapid development of textile fiber-based flexible wearable devices. However, the pristine textile fibers still can't meet the high standards for practical flexible wearable devices, which calls for the development of some effective modification strategies. In this review, we summarize the recent advances in the flexible wearable devices based on the textile fibers, putting special emphasis on the design and modifications of textile fibers. In addition, the applications of textile fibers in various fields and the critical role of textile fibers are also systematically discussed, which include the supercapacitors, sensors, triboelectric nanogenerators, thermoelectrics, and other self-powered electronic devices. Finally, the main challenges that should be overcome and some effective solutions are also manifested, which will guide the future development of more effective textile fiber-based flexible wearable devices.

9.
Am J Otolaryngol ; 45(4): 104265, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38703608

RESUMEN

OBJECTIVE: The characteristics of cervical lymph node involvement in papillary thyroid carcinoma (PTC) patients with different degree of capsular invasion remains unclear, especially for those with mono-focal lesion who have traditionally been considered as low neck metastasis risk subgroup. STUDY DESIGN: Retrospective cohort study. SETTING: Three academic teaching hospital. METHODS: A total of 1276 mono-focal PTC patients were retrospectively analyzed. RESULTS: Mono-focal PTC patients with extrathyroidal extension (ETE) showed significantly higher central lymph node metastasis (CLNM) rate than those without. For patients with no gross ETE (gETE), those with minimal ETE (mETE) also showed more commonly CLNM than those with encapsulated lesions. However, the lateral lymph node metastasis (LLNM) rates of patients with mETE and encapsulated tumors were comparable, both lower than that of patients with gETE. Age ≥40, male, and MTD ≥0.5 cm were identified as independent risk factors of CLNM for those with encapsulated tumors and were enrolled for creating a prediction model. In terms of LLNM, only MTD ≥1.0 cm was confirmed as independent risk factors of LLNM for patients with positive gETE. CONCLUSIONS: The presence and degree of ETE may have different effects on the risk of central and lateral lymph node metastasis. gETE demonstrates a strong correlation with both CLNM and LLNM while mETE is only associated with CLNM in mono-focal PTC patients. A comprehensive model is established in the aim of predicting neck involvement according to the capsular status and the corresponding stratified risk factors, which may aid clinical decision-making for the management of neck regions.


Asunto(s)
Ganglios Linfáticos , Metástasis Linfática , Cuello , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Humanos , Masculino , Femenino , Neoplasias de la Tiroides/patología , Cáncer Papilar Tiroideo/patología , Cáncer Papilar Tiroideo/secundario , Estudios Retrospectivos , Persona de Mediana Edad , Adulto , Cuello/patología , Ganglios Linfáticos/patología , Factores de Riesgo , Invasividad Neoplásica , Anciano , Factores de Edad , Estudios de Cohortes
10.
Foodborne Pathog Dis ; 21(1): 36-43, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37824752

RESUMEN

Enterococci can act as reservoirs for antibiotic-resistant genes that are potentially at risk of being transferred to other bacteria that inhabit in the gastrointestinal tract. The aim of this study was to determine the phenotypic and molecular characteristics of antibiotic-resistant enterococci isolated from probiotic preparations. In total, we isolated 15 suspected Enterococcus species from 5 compound probiotics, which were identified by 16S rDNA as 12 Enterococcus faecium and 3 Enterococcus faecalis. Determination of antimicrobial susceptibility by the microdilution broth method showed widespread resistance to sulfamethoxazole (100%), norfloxacin (99.3%), azithromycin (99.3%), gentamicin (86.7%), and chloramphenicol (20%). Whole genome sequencing of five resistant strains revealed that all had circular DNA chromosomes and that E. faecium J-1-A to J-4-A contained a plasmid, while E. faecalis J-5-A did not. The results of the resistance gene analysis revealed that each strain contained approximately 30 resistance genes, with the antibiotic resistance genes and the multidrug resistance efflux pump genes mdtG, lmrC, and lmrD detected in all strains. The chloramphenicol resistance genes ykkC and ykkD were first identified in E. faecalis. And there were 21, 19, 21, 21, and 29 virulence factors involved in strains, respectively. Further analysis of the gene islands (GIs) revealed that each strain contained more than 10 GIs. The above results confirm the existence of hidden dangers in the safety of probiotics and remind us to carefully select probiotic preparations containing enterococcal strains to avoid the potential spread of resistance and pathogenicity.


Asunto(s)
Enterococcus faecium , Probióticos , Enterococcus/genética , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Enterococcus faecium/genética , Enterococcus faecalis/genética , Cloranfenicol , Factores de Virulencia/genética
11.
Nano Lett ; 23(3): 1109-1118, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36716197

RESUMEN

Understanding physicochemical interactions and mechanisms related to the cell membranes of lives under extreme conditions is of essential importance but remains scarcely explored. Here, using a combination of computer simulations and experiments, we demonstrate that the structural integrity and controllable permeability of cell membranes at high temperatures are predominantly directed by configurational entropy emerging from distorted intermolecular organization of bipolar tethered lipids peculiar to the extremophiles. Detailed simulations across multiple scales─from an all-atom exploration of molecular mechanism to a mesoscale examination of its universal nature─suggest that this configurational entropy effect can be generalized to diverse systems, such as block copolymers. This offers biomimetic inspiration for designing heat-tolerant materials based on entropy, as validated by our experiments of synthetic polymers. The findings provide new insight into the basic nature of the mechanism underlying the adaptation of organisms to extreme conditions and might open paths for designed materials inspired by entropic effects in biological systems.


Asunto(s)
Extremófilos , Entropía , Simulación por Computador , Membrana Celular
12.
Int J Mol Sci ; 25(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38339223

RESUMEN

Aralia elata (Miq.) Seem is a medicinal plant that shares a common pathway for the biosynthesis of triterpenoid saponins with Panax ginseng. Here, we transferred the dammarenediol-II synthase gene from P. ginseng (PgDDS; GenBank: AB122080.1) to A. elata. The growth of 2-year-old transgenic plants (L27; 9.63 cm) was significantly decreased compared with wild-type plants (WT; 74.97 cm), and the leaflet shapes and sizes of the transgenic plants differed from those of the WT plants. Based on a terpene metabolome analysis of leaf extracts from WT, L13, and L27 plants, a new structural skeleton for ursane-type triterpenoid saponins was identified. Six upregulated differentially accumulated metabolites (DAMs) were detected, and the average levels of Rg3 and Re in the leaves of the L27 plants were 42.64 and 386.81 µg/g, respectively, increased significantly compared with the WT plants (15.48 and 316.96 µg/g, respectively). Thus, the expression of PgDDS in A. elata improved its medicinal value.


Asunto(s)
Aralia , Plantas Medicinales , Saponinas , Triterpenos , Aralia/genética , Aralia/química , Saponinas/química , Triterpenos/química , Plantas Medicinales/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Hojas de la Planta/metabolismo
13.
Molecules ; 29(3)2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38338468

RESUMEN

Recently, multicomponent reactions (MCRs) have attracted much attention in polymer synthesis. As one of the most well-known MCRs, the Kabachnik-Fields (KF) reaction has been widely used in the development of new functional polymers. The KF reaction can efficiently introduce functional groups into polymer structures; thus, polymers prepared via the KF reaction have unique α-aminophosphonates and show important bioactivity, metal chelating abilities, and flame-retardant properties. In this mini-review, we mainly summarize the latest advances in the KF reaction to synthesize functional polymers for the preparation of heavy metal adsorbents, multifunctional hydrogels, flame retardants, and bioimaging probes. We also discuss some emerging applications of functional polymers prepared by means of the KF reaction. Finally, we put forward our perspectives on the further development of the KF reaction in polymer chemistry.

14.
Clin Otolaryngol ; 49(4): 436-444, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38596906

RESUMEN

OBJECTIVES: To explore the predictive significance of baseline absolute peripheral lymphocyte counts (ALC) in the effectiveness of radiation in hypopharyngeal squamous cell carcinoma (HPSCC) patients. DESIGN, SETTING, AND PARTICIPANTS: A retrospective study of pathologically confirmed HPSCC patients who had definitive radiation between January 2020 and January 2022 at Fudan University Eye and ENT Hospital. The routine blood results of patients were obtained to determine if the baseline ALC was connected with the response to radiation. The receiver operator characteristic (ROC) curve and LASSO-based Cox regression were employed to assess the predictive value of ALC for the efficacy of radiotherapy (RT). MAIN OUTCOME MEASURES AND RESULTS: RT induced a considerable drop in ALC and the level of ALC did not revert to the baseline values 1 year after radiation. The baseline level of ALC was higher in patients who met complete response after RT. The baseline ALC and monocyte counts demonstrated the predictive value of radiation effectiveness and ALC was an independent predictor. CONCLUSION: In HPSCC, lymphocytes were sensitive to radiation and reduced significantly during RT. The baseline ALC might be regarded as a predictive indicator of the effectiveness of RT.


Asunto(s)
Neoplasias Hipofaríngeas , Humanos , Masculino , Recuento de Linfocitos , Estudios Retrospectivos , Femenino , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Hipofaríngeas/sangre , Neoplasias Hipofaríngeas/patología , Persona de Mediana Edad , Anciano , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Carcinoma de Células Escamosas de Cabeza y Cuello/sangre , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Resultado del Tratamiento , Valor Predictivo de las Pruebas , Adulto , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/patología , Curva ROC
15.
BMC Genomics ; 24(1): 359, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37369999

RESUMEN

BACKGROUND: The taxonomy and infrageneric delimitation of Phalaenopsis Blume has been significantly disputed due to some overlapping morphological features between species related, which needed further evidence for clarification. The structural characterization of complete chloroplast genomes of P. storbatiana and P. wilsonii were analyzed and compared with those of related taxa to provide a better understanding of their genomic information on taxonomy and phylogeny. RESULTS: It was shown that chloroplast genomes of Phalaenopsis storbatiana and P. wilsonii had a typical quadripartite structure with conserved genome arrangements and moderate divergence. The chloroplast genomes of P. storbatiana and P. wilsonii were 145,885 bp and 145,445 bp in length, respectively, and shared a similar GC content of 36.8%. Gene annotations of two species revealed 109 single-copy genes consistently. In addition, 20 genes duplicated in the inverted regions, 16 genes each possessed one or more introns, and five ndh (NA (D)H dehydrogenase) genes were observed in both. Comparative analysis of the total cp genomes of P. storbatiana and P. wilsonii with those of other six related Phalaenopsis species confirmed the stable sequence identity for coding and non-coding regions and higher sequence variation in SC regions than IR regions. Most of their protein-coding genes had a high degree of codon preference. Moreover, 45 genes were discovered with significantly positive selection. However, different amplifications in IR regions were observed in these eight species. Phylogenetic analysis based on CDS from 60 species representing main clades in Orchidaceae indicated that Phalaenopsis species including P. stobartiana and P. wilsonii formed a monophyletic clade with high bootstrap nested in tribe Vandeae of Epidendroideae, which was consistent with those from previous studies. CONCLUSIONS: The results could provide insight into understanding the plastome evolution and phylogenetic relationships of Phalaenopsis.


Asunto(s)
Genoma del Cloroplasto , Orchidaceae , Análisis de Secuencia de ADN/métodos , Filogenia , Orchidaceae/genética , Genómica
16.
J Am Chem Soc ; 145(32): 17710-17719, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37545395

RESUMEN

The stoichiometric conversion of methane to methanol by Cu-exchanged zeolites can be brought to highest yields by the presence of extraframework Al and high CH4 chemical potentials. Combining theory and experiments, the differences in chemical reactivity of monometallic Cu-oxo and bimetallic Cu-Al-oxo nanoclusters stabilized in zeolite mordenite (MOR) are investigated. Cu-L3 edge X-ray absorption near-edge structure (XANES), infrared (IR), and ultraviolet-visible (UV-vis) spectroscopies, in combination with CH4 oxidation activity tests, support the presence of two types of active clusters in MOR and allow quantification of the relative proportions of each type in dependence of the Cu concentration. Ab initio molecular dynamics (MD) calculations and thermodynamic analyses indicate that the superior performance of materials enriched in Cu-Al-oxo clusters is related to the activity of two µ-oxo bridges in the cluster. Replacing H2O with ethanol in the product extraction step led to the formation of ethyl methyl ether, expanding this way the applicability of these materials for the activation and functionalization of CH4. We show that competition between different ion-exchanged metal-oxo structures during the synthesis of Cu-exchanged zeolites determines the formation of active species, and this provides guidelines for the synthesis of highly active materials for CH4 activation and functionalization.

17.
J Am Chem Soc ; 145(13): 7113-7122, 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-36951270

RESUMEN

Cobalt-based catalysts have been widely used for Fischer-Tropsch synthesis (FTS) in industry; however, achieving rational catalyst design at the atomic level and thereby a higher activity and more long-chain-hydrocarbon products simultaneously remain an attractive and difficult challenge. The dual-atomic-site catalysts with unique electronic and geometric interface interactions offer a great opportunity for exploiting advanced FTS catalysts with improved performance. Herein, we designed a Ru1Zr1/Co catalyst with Ru and Zr dual atomic sites on the Co nanoparticle (NP) surface through a metal-organic-framework-mediated synthesis strategy which presents greatly enhanced FTS activity (high turnover frequency of 3.8 × 10-2 s-1 at 200 °C) and C5+ selectivity (80.7%). Control experiments presented a synergic effect between Ru and Zr single-atom site on Co NPs. Further density functional theory calculations of the chain growth process from C1 to C5 revealed that the designed Ru/Zr dual sites remarkably lower the rate-limiting barriers due to the significantly weakened C-O bond and promote the chain growth processes, resulting in the greatly boosted FTS performance. Therefore, our work demonstrates the effectiveness of dual-atomic-site design in promoting the FTS performance and provides new opportunities for developing efficient industrial catalysts.

18.
J Am Chem Soc ; 145(30): 16538-16547, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37466049

RESUMEN

Solid-electrolyte interphases (SEIs) in advanced rechargeable batteries ensure reversible electrode reactions at extreme potentials beyond the thermodynamic stability limits of electrolytes by insulating electrons while allowing the transport of working ions. Such selective ion transport occurs naturally in biological cell membranes as a ubiquitous prerequisite of many life processes and a foundation of biodiversity. In addition, cell membranes can selectively open and close the ion channels in response to external stimuli (e.g., electrical, chemical, mechanical, and thermal), giving rise to "gating" mechanisms that help manage intracellular reactions. We wondered whether the chemistry and structure of SEIs can mimic those of cell membranes, such that ion gating can be replicated. That is, can SEIs realize a reversible switching between two electrochemical behaviors, i.e., the ion intercalation chemistry of batteries and the ion adsorption of capacitors? Herein, we report such SEIs that result in thermally activated selective ion transport. The function of open/close gate switches is governed by the chemical and structural dynamics of SEIs under different thermal conditions, with precise behaviors as conducting and insulating interphases that enable battery and capacitive processes within a finite temperature window. Such an ion gating function is synergistically contributed by Arrhenius-activated ion transport and SEI dissolution/regrowth. Following the understanding of this new mechanism, we then develop an electrochemical method to heal the SEI layer in situ. The knowledge acquired in this work reveals the possibility of hitherto unknown biomimetic properties of SEIs, which will guide us to leverage such complexities to design better SEIs for future battery chemistries.

19.
Int J Cancer ; 153(1): 94-102, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36946652

RESUMEN

A high risk of developing second primary malignancy (SPM) has been reported among head and neck cancer patients. Here, we aimed to statistically quantify the impact of SPM development on the survival of head and neck cancer patients. Our study was conducted using the Surveillance, Epidemiology and End Results database to collect the data of 48 316 patients who received curative surgical resection for initial primary head and neck squamous cell carcinoma (IP-HNSCC) in 1975 to 2019. SPM diagnosis was treated as a time-varying covariate and multivariable Cox regression analysis was conducted to estimate the association between SPM development and survival, overall or by the subsite of IP-HNSCC. Of the included patients, 11 238 patients (23.3%) developed SPM during the follow-up period. A significant reduction in survival was observed among patients with SPM (hazard ratio [HR] for overall survival, 3.30; 95% confidence interval [CI]: 3.20-3.41). The impact of SPM development on reduced survival was more significant in patients with localized IP-HNSCC vs regional IP-HNSCC (HROS , 3.41; 95% CI: 3.24-3.6 vs HROS , 3.18; 95% CI: 3.05-3.31; P for interaction <.001). The survival impact of SPM development was more evident in younger patients than in older patients. SPM in lung and bronchus was associated with the most pronounced reduction in survival, overall and across all subsites of HNSCC. Our results indicated that SPM development led to a significant reduction in survival. A greater survival benefit may be achieved through intensive surveillance for SPM in lung and bronchus targeting younger patients and those with localized HNSCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias Primarias Secundarias , Humanos , Anciano , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias Primarias Secundarias/patología , Carcinoma de Células Escamosas/patología , Análisis de Regresión
20.
BMC Plant Biol ; 23(1): 531, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37914989

RESUMEN

Bleeding is as particularly a serious phenomenon in Actinidia arguta and has important effects on this plant's growth and development. Here we used A. arguta to study the effects of bleeding on the growth and development of leaves and fruits after a bleeding episode. We detect and analyze physiological indices of leaves and fruit after bleeding. The result revealed that the relative electrical conductivity and malondialdehyde (MDA) of leaves increased in treatment. Nitro blue tetrazolium chloride (NBT) and 3,3-diaminobenzidine (DAB) staining revealed the accumulation of reactive oxygen species (ROS) in leaves after bleeding. The chlorophyll content and photosynthetic parameter of plants were also decreased. In fruits, pulp and seed water content decreased after the damage, as did fruit vitamin C (Vc), soluble sugar content, and soluble solids content (SSC); the titratable acid content did not change significantly. We therefore conclude that bleeding affects the physiological indices of A. arguta. Our study provides a theoretical basis for understanding the physiological changes of A. arguta after bleeding episodes and laying a timely foundation for advancing research on A. arguta bleeding and long-term field studies should be executed in order to gain insights into underlying mechanisms.


Asunto(s)
Actinidia , Frutas , Semillas , Ácido Ascórbico
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