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1.
ACS Nano ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38995677

RESUMEN

The band gap constraint of the photocatalyst for overall water splitting limits the utilization of solar energy. A strategy to broaden the range of light absorption is employing a two-dimensional (2D) polar material as photocatalyst, benefiting from the deflection of the energy level due to their intrinsic internal electric field. Here, by using first-principles computational screening, we search for 2D polar semiconductors for photocatalytic water splitting from both ground- and excited-state perspectives. Applying a unique electronic structure model of polar materials, there are 13 photocatalyst candidates for the hydrogen evolution reaction (HER) and 8 candidates for the oxygen evolution reaction (OER) without barrier energies from the perspective of the ground-state free energy variation calculation. In particular, Cu2As4Cl2S3 and Cu2As4Br2S3 can catalyze HER and OER simultaneously, becoming promising photocatalysts for overall water splitting. Furthermore, by combining ground-state band structure calculations with excited-state charge distribution and transfer calculated by linear-response time-dependent density functional theory (LR-TDDFT) and time-dependent ab initio nonadiabatic molecular dynamics (NAMD), respectively, the rationality of the 2D polar material model has been manifested. The intrinsic built-in electric field promotes the separation of charge carriers while suppressing their recombination. Therefore, our computational work provides a high-throughput method to design high-performance photocatalysts for water splitting.

2.
J Chem Theory Comput ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976399

RESUMEN

Recent advancements in neural networks have led to significant progress in addressing many-body electron correlations in small molecules and various physical models. In this work, we propose QiankunNet-Solid, which incorporates periodic boundary conditions into the neural network quantum state (NNQS) framework based on generative Transformer architecture along with a batched autoregressive sampling (BAS) method, enabling the effective ab initio calculation of real solid materials. The accuracy of this method is demonstrated in one-, two-, and three-dimensional periodic systems, with results comparable to those of full configuration interaction and coupled-cluster method, even in the strongly correlated regime. Furthermore, we compute the band structures and density of states for silicon crystal. The successful incorporation of periodic boundary conditions into the NNQS framework through QiankunNet-Solid opens up new possibilities for the accurate and efficient study of electronic structure properties in solid-state physics.

3.
ACS Appl Mater Interfaces ; 16(26): 33081-33092, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888094

RESUMEN

Inflammatory bowel disease (IBD) is a chronic and recurrent inflammatory disease that affects the gastrointestinal tract. The major hurdles impeding IBD treatment are the low targeting efficiency and short retention time of drugs in IBD sites. Nanoparticles with specific shapes have demonstrated the ability to improve mucus retention and cellular uptake. Herein, mesoporous silica nanoparticles (MSNs) with various morphologies were used to deliver budesonide (BUD) for the treatment of IBD. The therapeutic efficacy is strongly dependent on their shapes. The system comprises different shapes of MSNs as carriers for budesonide (BUD), along with Eudragit S100 as the enteric release shell. The encapsulation of Eudragit S100 not only improved the stability of MSNs-BUD in the gastrointestinal tract but also conferred pH-responsive drug release properties. Then, MSNs efficiently deliver BUD to the colon site, and the special shape of MSNs plays a critical role in enhancing their permeability and retention in the mucus layer. Among them, dendritic MSNs (MSND) effectively reduced myeloperoxidase (MPO) activity and levels of inflammatory cytokines in the colon due to long retention time and rapid release in IBD sites, thereby enhancing the therapeutic efficacy against colitis. Given the special shapes of MSNs and pH-responsivity of Eudragit S100, BUD loaded in the voids of MSND (E@MSNs-BUD) could penetrate the mucous layer and be accurately delivered to the colon with minor side effects. This system is expected to complement current treatment strategies for the IBD.


Asunto(s)
Budesonida , Portadores de Fármacos , Enfermedades Inflamatorias del Intestino , Nanopartículas , Dióxido de Silicio , Budesonida/química , Budesonida/administración & dosificación , Budesonida/uso terapéutico , Budesonida/farmacocinética , Nanopartículas/química , Nanopartículas/uso terapéutico , Animales , Dióxido de Silicio/química , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/patología , Portadores de Fármacos/química , Ratones , Ácidos Polimetacrílicos/química , Liberación de Fármacos , Humanos , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Antiinflamatorios/administración & dosificación , Porosidad , Concentración de Iones de Hidrógeno
4.
NPJ Biofilms Microbiomes ; 10(1): 51, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902226

RESUMEN

Bacteria induced metamorphosis observed in nearly all marine invertebrates. However, the mechanism of bacteria regulating the larvae-juvenile metamorphosis remains unknown. Here, we test the hypothesis that c-di-GMP, a ubiquitous bacterial second-messenger molecule, directly triggers the mollusc Mytilus coruscus larval metamorphosis via the stimulator of interferon genes (STING) receptor. We determined that the deletion of c-di-GMP synthesis genes resulted in reduced c-di-GMP levels and biofilm-inducing activity on larval metamorphosis, accompanied by alterations in extracellular polymeric substances. Additionally, c-di-GMP extracted from tested varying marine bacteria all exhibited inducing activity on larval metamorphosis. Simultaneously, through pharmacological and molecular experiments, we demonstrated that M. coruscus STING (McSTING) participates in larval metamorphosis by binding with c-di-GMP. Our findings reveal that new role of bacterial c-di-GMP that triggers mussel larval metamorphosis transition, and extend knowledge in the interaction of bacteria and host development in marine ecosystems.


Asunto(s)
Biopelículas , GMP Cíclico , Larva , Metamorfosis Biológica , Mytilus , Animales , Larva/microbiología , Larva/crecimiento & desarrollo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Biopelículas/crecimiento & desarrollo , Mytilus/microbiología , Mytilus/crecimiento & desarrollo , Bacterias/genética , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/crecimiento & desarrollo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo
5.
Eur J Pharm Biopharm ; 201: 114353, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38885911

RESUMEN

The latent reservoir of human immunodeficiency virus (HIV) is a major obstacle in the treatment of acquired immune deficiency syndrome (AIDS). The "shock and kill" strategy has emerged as a promising approach for clearing HIV latent reservoirs. However, current latency-reversing agents (LRAs) have limitations in effectively and safely activating the latent virus and reducing the HIV latent reservoirs in clinical practice. Previously, EK-16A was extracted from Euphorbia kansui, which had the effect of interfering with the HIV-1 latent reservoir and inhibiting HIV-1 entry. Nevertheless, there is no suitable and efficient EK-16A oral formulation for in vivo delivery and clinical use. In this study, an oral EK-16A self-nanoemulsifying drug delivery system (EK-16A-SNEDDS) was proposed to "shock" the HIV-1 latent reservoir. This system aims to enhance the bioavailability and delivery of EK-16A to various organs. The composition of EK-16A-SNEDDS was optimized through self-emulsifying grading and ternary phase diagram tests. Cell models, pharmacokinetic experiments, and pharmacodynamics in HIV-1 latent cell transplant animal models suggested that EK-16A-SNEDDS could be absorbed by the gastrointestinal tract and enter the blood circulation after oral administration, thereby reaching various organs to activate latent HIV-1. The prepared EK-16A-SNEDDS demonstrated safety and efficacy, exhibited high clinical experimental potential, and may be a promising oral preparation for eliminating HIV-1 latent reservoirs.


Asunto(s)
Emulsiones , VIH-1 , Latencia del Virus , VIH-1/efectos de los fármacos , Latencia del Virus/efectos de los fármacos , Animales , Administración Oral , Humanos , Activación Viral/efectos de los fármacos , Euphorbia/química , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Disponibilidad Biológica , Sistema de Administración de Fármacos con Nanopartículas , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/farmacocinética , Masculino , Sistemas de Liberación de Medicamentos/métodos , Ratones
6.
Adv Mater ; 36(28): e2311926, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38703354

RESUMEN

Traditional lithium-ion battery (LIB) anodes, whether intercalation-type like graphite or alloying-type like silicon, employing a single lithium storage mechanism, are often limited by modest capacity or substantial volume changes. Here, the kesterite multi-metal dichalcogenide (CZTSSe) is introduced as an anode material that harnesses a conversion-alloying hybrid lithium storage mechanism. Results unveil that during the charge-discharge processes, the CZTSSe undergoes a comprehensive phase evolution, transitioning from kesterite structure to multiple dominant phases of sulfides, selenides, metals, and alloys. The involvement of multi-components facilitates electron transport and mitigates swelling stress; meanwhile, it results in formation of abundant defects and heterojunctions, allowing for increased lithium storage active sites and reduced lithium diffusion barrier. The CZTSSe delivers a high specific capacity of up to 2266 mA h g-1 at 0.1 A g-1; while, maintaining a stable output of 116 mA h g-1 after 10 000 cycles at 20 A g-1. It also demonstrates remarkable low-temperature performance, retaining 987 mA h g-1 even after 600 cycles at -40 °C. When employed in full cells, a high specific energy of 562 Wh kg-1 is achieved, rivalling many state-of-the-art LIBs. This research offers valuable insights into the design of LIB electrodes leveraging multiple lithium storage mechanisms.

7.
Adv Colloid Interface Sci ; 330: 103198, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38820884

RESUMEN

Particle-stabilized technique for fabricating foam ceramics was developed in 2006. Porous ceramics with porosity over 95% can be prepared by this newly developed method. This foaming technique was derived from the principle of Pickering foam to a large extent. The high internal phase volume, narrow distribution of pore size as well as the structural stability of the Pickering system enable the final ceramic products to realize their functionality in a variety of applications. However, the interfacial aspect of the foaming system determines the final product in many ways, which brings this novel method details to explore and possibilities to challenge. The current review introduces the particle-stabilized method combining with colloid and surface science since particles are the building block of ceramic materials. The history of this newly invented method was mentioned at first, followed by foam ceramic products prepared by this foaming technique combining with corresponding mechanism. Some representative applications involving ceramic materials made by particle-stabilized method were discussed. At last, we conclude the overall article and put forward some outlooks and challenges about the future direction of this unique foaming technique.

8.
J Pharm Biomed Anal ; 246: 116204, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38776584

RESUMEN

Lamiophlomis Herba (LH) is a traditional Chinese and Tibetan dual-use herb with hemostatic and analgesic effects, and is widely used in the clinical treatment of traumatic bleeding and pain. In recent years, LH has been proven to treat liver fibrosis (LF), but the chemical components related to the pharmacological properties of LH in the treatment of LF are still unclear. Based on the theory of plasma pharmachemistry, the characteristic components in water extract and drug-containing plasma samples of LH were qualitatively analyzed by UPLC-Q-TOF-MS. The chemical components in plasma were screened and the targets were predicted by network pharmacology. Then, the predicted components and targets were verified in vitro by Elisa and qRT-PCR technology. Finally, the pharmacological effects of LH and its monomeric components were determined by hematoxylin-eosin staining of rat liver. A total of 50 chemical constituents were identified in LH, of which 12 were blood prototypes and 9 were metabolites. In vitro experiments showed that LH and its monomeric components luteolin, shanzhiside methyl ester, loganic acid, loganin, 8-O-acetyl shanzhiside methyl ester could increase the expression of antioxidant genes (NQO-1, HO-1) and decrease the expression of inflammatory genes (IL-6, IL-18), thereby reducing the expression of extracellular matrix-related genes and proteins (COL1A1, COL3A1, LN, α-sma, PC-III, Col-IV). In vivo experiments showed that LH could reduce the area of LF in rats in a dose-dependent manner, and shanzhiside methyl ester and 8-O-acetyl shanzhiside methyl ester may be the main components in pharmacodynamics. These effects may be mediated by LH-mediated Nrf2/NF-κB pathway. This study explored the potential pharmacodynamic components of LH in the treatment of LF, and confirmed that shanzhiside methyl ester and 8-O-acetyl shanzhiside methyl ester play a key role in the treatment of LF with LH.


Asunto(s)
Medicamentos Herbarios Chinos , Cirrosis Hepática , Farmacología en Red , Ratas Sprague-Dawley , Animales , Ratas , Masculino , Farmacología en Red/métodos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Cirrosis Hepática/tratamiento farmacológico , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Humanos , Cromatografía Líquida de Alta Presión/métodos , Lamiaceae/química
9.
Phys Chem Chem Phys ; 26(22): 15831-15843, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38787657

RESUMEN

High performance computing (HPC) is renowned for its capacity to tackle complex problems. Meanwhile, quantum computing (QC) provides a potential way to accurately and efficiently solve quantum chemistry problems. The emerging field of quantum-centric high performance computing (QCHPC), which merges these two powerful technologies, is anticipated to enhance computational capabilities for solving challenging problems in quantum chemistry. The implementation of QCHPC for quantum chemistry requires interdisciplinary research and collaboration across multiple fields, including quantum chemistry, quantum physics, computer science and so on. This perspective provides an introduction to the quantum algorithms that are suitable for deployment in QCHPC, focusing on conceptual insights rather than technical details. Parallel strategies to implement these algorithms on quantum-centric supercomputers are discussed. We also summarize high performance quantum emulating simulators, which are considered a viable tool to explore QCHPC. We conclude with challenges and outlooks in this field.

10.
Chem Sci ; 15(18): 6916-6923, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38725518

RESUMEN

Two-dimensional (2D) nonmagnetic semiconductors with large Rashba-Dresselhaus (R-D) spin splitting at valence or conduction bands are attractive for magnetic-field-free spintronic applications. However, so far, the number of 2D R-D inorganic semiconductors has been quite limited, and the factors that determine R-D spin splitting as well as rational design of giant spin splitting, remain unclear. For this purpose, by exploiting 2D chiral metal-organic frameworks (CMOFs) as a platform, we theoretically develop a three-step screening method to obtain a series of candidate 2D R-D semiconductors with valence band spin splitting up to 97.2 meV and corresponding R-D coupling constants up to 1.37 eV Å. Interestingly, the valence band spin texture is reversible by flipping the chirality of CMOFs. Furthermore, five keys for obtaining giant R-D spin splitting in 2D CMOFs are successfully identified: (i) chirality, (ii) large spin-orbit coupling, (iii) narrow band gap, (iv) valence and conduction bands having the same symmetry at the Γ point, and (v) strong ligand field.

11.
Bioact Mater ; 39: 191-205, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38808157

RESUMEN

Unnecessary exposure to ionizing radiation (IR) often causes acute and chronic oxidative damages to normal cells and organs, leading to serious physiological and even life-threatening consequences. Amifostine (AMF) is a validated radioprotectant extensively applied in radiation and chemotherapy medicine, but the short half-life limits its bioavailability and clinical applications, remaining as a great challenge to be addressed. DNA-assembled nanostructures especially the tetrahedral framework nucleic acids (tFNAs) are promising nanocarriers with preeminent biosafety, low biotoxicity, and high transport efficiency. The tFNAs also have a relative long-term maintenance for structural stability and excellent endocytosis capacity. We therefore synthesized a tFNA-based delivery system of AMF for multi-organ radioprotection (tFNAs@AMF, also termed nanosuit). By establishing the mice models of accidental total body irradiation (TBI) and radiotherapy model of Lewis lung cancer, we demonstrated that the nanosuit could shield normal cells from IR-induced DNA damage by regulating the molecular biomarkers of anti-apoptosis and anti-oxidative stress. In the accidental total body irradiation (TBI) mice model, the nanosuit pretreated mice exhibited satisfactory alteration of superoxide dismutase (SOD) activities and malondialdehyde (MDA) contents, and functional recovery of hematopoietic system, reducing IR-induced pathological damages of multi-organ and safeguarding mice from lethal radiation. More importantly, the nanosuit showed a selective radioprotection of the normal organs without interferences of tumor control in the radiotherapy model of Lewis lung cancer. Based on a conveniently available DNA tetrahedron-based nanocarrier, this work presents a high-efficiency delivery system of AMF with the prolonged half-life and enhanced radioprotection for multi-organs. Such nanosuit pioneers a promising strategy with great clinical translation potential for radioactivity protection.

12.
J Phys Chem Lett ; 15(21): 5643-5653, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38767198

RESUMEN

The understanding of the reaction mechanism of CO2 electroreduction (CO2RR) is essential for the precise design of catalysts for specific products with high selectivity. In this work, combined with the computational hydrogen electrode model and kinetic energy barrier calculations, CO2RR pathways on Cu(100) and Al1Cu3(100) are intensively investigated. The free energy barrier of the rate-determining step of ethylene formation is reduced from 1.08 eV for *CCOH formation on Cu(100) to 0.51 eV for *CH2OCHOH formation on Al1Cu3(100) and enhances the catalytic activity. The reaction free energy of *CO-*CO coupling is remarkably reduced from 0.86 eV on Cu(100) to -0.43 eV on Al1Cu3(100) and the coupling barrier is reduced from 0.97 to 0.37 eV, suppressing the production of gas phase CO and enhancing the production of C2 products. Furthermore, the selectivity toward C-O breaking of *CH2CHOH on Cu(100) and *CH2CH2OH on Al1Cu3(100) ensures high selectivity toward ethene rather than ethanol.

13.
J Phys Chem Lett ; 15(18): 5016-5023, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38695756

RESUMEN

The pursuit of efficient photocatalysts toward photocatalytic water splitting has attracted wide attention. However, the low efficiency of photocatalytic reactions due to the rapid electron-hole recombination and the time-consuming searching process hinder the development of high-performance photocatalysts. Here, we proposed a data-driven screening procedure for covalent organic frameworks (COFs) as overall solar water-splitting photocatalysts. Based on a COF database through assembling different Cores and Linkers, three COFs are predicted to be efficient photocatalysts for overall solar water splitting after high-throughput computational screening. We found that the photogenerated electrons and holes are well separated on single COF photocatalysts without material engineering, and both hydrogen and oxygen evolution reactions can occur spontaneously on the three screened COFs under visible light radiation. This kind of novel COF screened by a data-driven screening procedure offers new perspectives for advancing efficient photocatalysts.

14.
Blood Adv ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820490

RESUMEN

Signal peptide (SP) is essential for protein secretion, and pathogenic variants in the SP of FIX have been identified in hemophilia B (HB). However, the underlying mechanism for the genotype-phenotype correlation of these variants has not been well studied. Here we systematically examined the effects of 13 pathogenic point variants in the SP of FIX using different approaches. Our results showed that these point variants lead to HB by missense variants and/or aberrant pre-mRNA splicing. The missense variants in h-region mainly affected the co-translational translocation function of the SP, and those in c-region caused FIX deficiency mainly by disturbing the co-translational translocation and/or cleavage of the SP. Almost absolute aberrant pre-mRNA splicing was only observed in variants of c.82T>G, but a slight change of splicing patterns was found in variants of c.53G>T, c.77C>A, c.82T>C, and c.83G>A, indicating that these variants might have different degree to affect pre-mRNA splicing. Although two 6-nt deletion aberrant pre-mRNA splicing products caused FIX deficiency by disturbing the SP cleavage, but they could produce some functional mature FIX and vitamin K could increase the secretion of functional FIX. Taken together, our data indicated that pathogenic variants in the SP of FIX caused HB through diverse molecular mechanisms or even a mixture of several mechanisms, and vitamin K availability could be partially attributed to varying bleeding tendencies in patients carrying the same variant in the SP.

15.
Nano Lett ; 24(21): 6425-6432, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38747348

RESUMEN

Two-dimensional semiconductor materials with vertical dipoles are promising photocatalysts as vertical dipoles not only promote the electron-hole separation but also enhance the carrier redox ability. However, the influence of vertical dipoles on carrier recombination in such materials, especially the competing relationship between vertical dipoles and band gaps, is not yet clear. Herein, first-principles calculations and nonadiabatic molecular dynamics simulations were combined to clarify the influence of band gap and vertical dipole on the carrier lifetime in Janus MoSSe monolayer. By comparing with the results of MoS2 and MoSe2 as well as exploring the carrier lifetime of MoSSe under strain regulation, it has been demonstrated that the vertical dipole, rather than the band gap, is the dominant factor affecting the carrier lifetime. Strikingly, a linear relationship between the carrier lifetime and vertical dipole is revealed. These findings have important implications for the design of high-performance photocatalysts and optoelectronic devices.

16.
J Phys Chem Lett ; 15(15): 4218-4223, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38602298

RESUMEN

Two-dimensional (2D) ferroelectric metals (FEMs) possess intriguing characteristics, such as unconventional superconductivity and the nonlinear anomalous Hall effect. However, their occurrence is exceedingly rare due to mutual repulsion between ferroelectricity and metallicity. In addition, further incorporating other features like ferromagnetism into FEMs to enhance their functionalities poses a significantly greater challenge. Here, via first-principles calculations, we demonstrate a case of an FEM that features a coexistence of room-temperature ferromagnetism, ferroelectricity, and metallicity in a thermodynamically stable 2D Os2Se3. It presents a vertical electric polarization of 3.00 pC/m that exceeds those of most FEMs and a moderate polarization switching barrier of 0.22 eV per formula unit. Moreover, 2D Os2Se3 exhibits robust ferromagnetism (Curie temperature TC ≈ 527 K) and a sizable magnetic anisotropy energy (-30.87 meV per formula unit). Furthermore, highly magnetization-dependent electrical conductivity is revealed, indicative of strong magnetoelectric coupling. Berry curvature calculation suggests that the FEM might exhibit nontrivial band topology.

17.
Nano Lett ; 24(15): 4433-4438, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38564276

RESUMEN

Twisted bilayer graphene (TBG) has the natural merits of tunable flat bands and localized states distributed as a triangular lattice. However, the application of this state remains obscure. By density functional theory (DFT) and pz orbital tight-binding model calculations, we investigate the tip-shaped electrostatic potential of top valence electrons of TBG at half filling. Adsorption energy scanning of molecules above the TBG reveals that this tip efficiently attracts molecules selectively to AA-stacked or AB-stacked regions. Tip shapes can be controlled by their underlying electronic structure, with electrons of low bandwidth exhibiting a more localized feature. Our results indicate that TBG tips offer applications in noninvasive and nonpolluting measurements in scanning probe microscopy and theoretical guidance for 2D material-based probes.

18.
iScience ; 27(5): 109599, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38646178

RESUMEN

Alstonia scholaris of the Apocynaceae family is a medicinal plant with a rich source of bioactive monoterpenoid indole alkaloids (MIAs), which possess anti-cancer activity like vinca alkaloids. To gain genomic insights into MIA biosynthesis, we assembled a high-quality chromosome-level genome for A. scholaris using nanopore and Hi-C data. The 444.95 Mb genome contained 35,488 protein-coding genes. A total of 20 chromosomes were assembled with a scaffold N50 of 21.75 Mb. The genome contained a cluster of strictosidine synthases and tryptophan decarboxylases with synteny to other species and a saccharide-terpene cluster involved in the monoterpenoid biosynthesis pathway of the MIA upstream pathway. The multi-omics data of A. scholaris provide a valuable resource for understanding the evolutionary origins of MIAs and for discovering biosynthetic pathways and synthetic biology efforts for producing pharmaceutically useful alkaloids.

19.
Nano Lett ; 24(17): 5317-5323, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38635037

RESUMEN

Exploring high-efficiency photocatalysts for selective CO2 reduction is still challenging because of the limited charge separation and surface reactions. In this study, a noble-metal-free metallic VSe2 nanosheet was incorporated on g-C3N4 to serve as an electron capture and transfer center, activating surface active sites for highly efficient and selective CO2 photoreduction. Quasi in situ X-ray photoelectron spectroscopy (XPS), soft X-ray absorption spectroscopy (sXAS), and femtosecond transient absorption spectroscopy (fs-TAS) unveiled that VSe2 could capture electrons, which are further transferred to the surface for activating active sites. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) calculations revealed a kinetically feasible process for the formation of a key intermediate and confirmed the favorable production of CO on the VSe2/PCN (protonated C3N4) photocatalyst. As an outcome, the optimized VSe2/PCN composite achieved 97% selectivity for solar-light-driven CO2 conversion to CO with a high rate of 16.3 µmol·g-1·h-1, without any sacrificial reagent or photosensitizer. This work offers new insights into the photocatalyst design toward highly efficient and selective CO2 conversion.

20.
Nat Commun ; 15(1): 2969, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582766

RESUMEN

Artificial electronic kagome lattices may emerge from electronic potential landscapes using customized structures with exotic supersymmetries, benefiting from the confinement of Shockley surface-state electrons on coinage metals, which offers a flexible approach to realizing intriguing quantum phases of matter that are highly desired but scarce in available kagome materials. Here, we devise a general strategy to construct varieties of electronic kagome lattices by utilizing the on-surface synthesis of halogen hydrogen-bonded organic frameworks (XHOFs). As a proof of concept, we demonstrate three XHOFs on Ag(111) and Au(111) surfaces, which correspondingly deliver regular, breathing, and chiral breathing diatomic-kagome lattices with patterned potential landscapes, showing evident topological edge states at the interfaces. The combination of scanning tunnelling microscopy and noncontact atomic force microscopy, complemented by density functional theory and tight-binding calculations, directly substantiates our method as a reliable and effective way to achieve electronic kagome lattices for engineering quantum states.

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