Emerging roles and mechanisms of lncRNAs in fruit and vegetables.

With the development of genome sequencing technologies, many long non-coding RNAs (lncRNAs) have been identified in fruit and vegetables. lncRNAs are primarily transcribed and spliced by RNA polymerase II (Pol II) or plant-specific Pol IV/V, and exhibit limited evolutionary conservation. lncRNAs intricately regulate various aspects of fruit and vegetables, including pigment accumulation, reproductive tissue development, fruit ripening, and responses to biotic and abiotic stresses, through diverse mechanisms such as gene expression modulation, interaction with hormones and transcription factors, microRNA regulation, and involvement in alternative splicing. This review presents a comprehensive overview of lncRNA classification, basic characteristics, and, most importantly, recent advances in understanding their functions and regulatory mechanisms.

Boosting Electrocatalytic Ammonia Synthesis of Bio-Inspired Porous Mo-Doped Hematite via Nitrogen Activation.

Electrochemical N2 reduction reaction (NRR) emerges as a highly attractive alternative to the Haber-Bosch process for producing ammonia (NH3) under ambient circumstances. Currently, this technology still faces tremendous challenges due to the low ammonia production rate and low Faradaic efficiency, urgently prompting researchers to explore highly efficient electrocatalysts. Inspired by the Fe-Mo cofactor in nitrogenase, we report Mo-doped hematite (Fe2O3) porous nanospheres containing Fe-O-Mo subunits for enhanced activity and selectivity in the electrochemical reduction from N2 to NH3. Mo-doping induces the morphology change from a solid sphere to a porous sphere and enriches lattice defects, creating more active sites. It also regulates the electronic structures of Fe2O3 to accelerate charge transfer and enhance the intrinsic activity. As a consequence, Mo-doped Fe2O3 achieves effective N2 fixation with a high ammonia production rate of 21.3 ± 1.1 µg h-1 mgcat.-1 as well as a prominent Faradaic efficiency (FE) of 11.2 ± 0.6%, superior to the undoped Fe2O3 and other iron oxide catalysts. Density functional theory (DFT) calculations further unravel that the Mo-doping in Fe2O3 (110) narrows the band gap, promotes the N2 activation on the Mo site with an elongated N≡N bond length of 1.132 Å in the end-on configuration, and optimizes an associative distal pathway with a decreased energy barrier. Our results may pave the way toward enhancing the electrocatalytic NRR performance of iron-based materials by atomic-scale heteroatom doping.

In Situ SERS Detection of Photocatalytic Degradation of Aminothiophenol on Carbon-Nanotubes/CoPt Hollow Nanoparticles Composite.

The phenol derivatives, as one kind of hormone, are analogous to endocrine disruptors with high carcinogenicity. The photocatalytic technology is an effective approach to mitigate environmental pollution by utilizing solar energy to degrade organic pollutants. In this work, CoPt hollow nanoparticles (NPs) attached to carbon nanotubes (CNTs) are employed to catalytically decompose the p-aminothiophenol (PATP) molecules under light irradiation, which is monitored by using surface-enhanced Raman scattering spectra. The effect of temperature on the catalytic efficacy of CoPt hollow NPs is investigated. Moreover, the use of CNTs coating on CoPt NPs is found to accelerate the photocatalytic degradation rate of PATP molecules, attributed to the enhanced plasmon-exciton coupling interaction of the CoPt/CNTs hybrid configuration.

Theoretical study on contribution of charge transfer effect to surface-enhanced Raman scattering spectra of pyridine adsorbed on Ag(n) (n = 2-8) clusters.

We investigate surface-enhanced Raman scattering (SERS) spectra of pyridine-Ag(n) (n = 2-8) complexes by density functional theory (DFT) and time-dependent DFT (TDDFT) methods. In simulated normal Raman scattering (NRS) spectra, profiles of pyridine-Ag(n) (n = 2-8) complexes are analogical with that of isolated pyridine. Nevertheless, calculated pre-SERS spectra are strongly dependent on electronic transition states of new complexes. Wavelengths at 335 nm, 394.8 nm, 316.9 nm and 342.6 nm, which are nearly resonant with pure charge transfer excitation states, are adopted as incident light when simulating pre-SERS spectra for pyridine-Ag(n) (n = 2-8) complexes, respectively. We obtain enhancement factors from 10(3) to 10(5) in pre-SERS spectra compared with corresponding NRS spectra. The obvious increase in Raman intensities mainly result from charge transfer resonance Raman enhancement. A charge difference densities (CDDs) methodology is adopted in describing chemical enhancement mechanism. This methodology aims at visualizing charge transfer from Ag(n) (n = 2-8) clusters to pyridine on resonant electronic transition, which is one of the most direct evidences for chemical enhancement mechanism.

[Drought-resistance evaluation of marigold cultivars based on multiple statistics analysis].

By the methods of principal component analysis, subordinate function, and cluster analysis, a comprehensive evaluation was conducted on the drought-resistance of 16 physiological indices of nine marigold cultivars. Under drought stress, the 16 physiological indices had different responses, among which, free proline (Pro), H2O2, and ascorbate peroxidase (APX) showed the greatest sensitivity. There existed significant correlations in the drought-resistance coefficients of parts of the physiological indices. Four principal factors presented 88.6% of the information of the 16 indices, and the cultivars 'Janie' and 'Gate gold', 'Bonanzn', 'Janie', and 'Chokdee' had the strongest drought-resistance for the 4 principal factors, respectively. The comprehensive evaluation value of the drought-resistance of the 9 cultivars was in the order of 'Janie' > 'Gate gold' > 'Bonanza' > 'Chokdee' > 'Giant' > 'Great hero' > 'Little hero' > 'Durango' > 'Discovery'. The 9 cultivars could be clustered into 3 groups, and 'Gate gold', 'Janie', 'Bonanza' and 'Chokdee' belonged to the drought-resistance group.

Electronic structure and optical properties of dianionic and dicationic pi-dimers.

The absorption spectra of dianionic tetrocyanoethylene and dicationic tetrathiafulvalene dimers have been studied theoretically with the time-dependent density functional theory and the recently proposed Coulomb-attenuated model. The nature of the excited states was further explored by means of the two-dimensional (2D) site (transition density matrix) and three-dimensional (3D) cube (transition density and charge difference density) representations. By use of the 3D transition density and charge difference density, we visualized the orientation of transition dipole moment and also explained charge-transfer characteristics occurring in the dianionic/dicationic pi-dimers system. It is found that for the dianionic/dicationic pi-dimers system there exist two kinds of charge-transfer patterns for the mainly excited states, the intermolecular charge transfer and the mixture of intramolecular charge transfer coupled with intermolecular charge transfer. Meanwhile, the coupling effect of excitation and the oscillation of electron-hole pairs between the monomers have been revealed with 2D site representation of transition density matrix, which also indicates the electron-hole coherence upon photon excitation.

Density functional theory study on Herzberg-Teller contribution in Raman scattering from 4-aminothiophenol-metal complex and metal-4-aminothiophenol-metal junction.

Density functional theory (DFT) and time-dependent DFT calculations have been performed to investigate the Raman scattering spectra of metal-molecule complex and metal-molecule-metal junction architectures interconnected with 4-aminothiophenol (PATP) molecule. The simulated profiles of normal Raman scattering (NRS) spectra for the two complexes (Ag(2)-PATP and PATP-Au(2)) and the two junctions (Ag(2)-PATP-Au(2) and Au(2)-PATP-Ag(2)) are similar to each other, but exhibit obviously different Raman intensities. Due to the lager static polarizabilities of the two junctions, which directly influence the ground state chemical enhancement in NRS spectra, the calculated normal Raman intensities of them are stronger than those of two complexes by the factor of 10(2). We calculate preresonance Raman scattering (RRS) spectra with incident light at 1064 nm, which is much lower than the S(1) electronic transition energy of complexes and junctions. Ag(2)-PATP-Au(2) and Au(2)-PATP-Ag(2) junctions yield higher Raman intensities than those of Ag(2)-PATP and PATP-Au(2) complexes, especially for b(2) modes. This effect is mainly attributed to charge transfer (CT) between the metal gap and the PAPT molecule which results in the occurrence of CT resonance enhancement. The calculated pre-RRS spectra strongly depend on the electronic transition state produced by new structures. With excitation at 514.5 nm, the calculated pre-RRS spectra of two complexes and two junctions are stronger than those of with excitation at 1064 nm. A charge difference densities methodology has been used to visually describe chemical enhancement mechanism of RRS spectrum. This methodology aims at visualizing intermolecular CT which provides direct evidence of the Herzberg-Teller mechanism.