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Summary: During space travel, microgravity leads to disturbances in cognitive function, while the underlying mechanism is still unclear. Simulated microgravity mice showed neuronal age-like changes in the hippocampus of our study. In the context of microgravity, we discovered m6A modification reshapes in the hippocampal region. When paired with RNA-seq and MeRIP-seq, Shox2 was found to be a powerful regulator in hippocampal neuron that respondes to microgravity. Decreased expression of senescence-associated secretory phenotype factors and improved genes related to synapses led to the restoration of memory function in the hippocampus upon increased expression of Shox2. Moreover, we discovered that IGF2BP2 was required for the m6A modification of the Shox2, and overexpressed IGF2BP2 in the hippocampus protected against both neuronal senescence and learning and memory decline caused by loss of gravity. Accordingly, our research identified the hippocampal IGF2BP2-Shox2 axis as a possible therapeutic approach to maintaining cognitive function during space travel.

To tackle the prevalent challenges encountered with polyamine-based non-aqueous absorbents (NAAs), particularly the formation of viscous products and inferior regeneration performance, this study proposed an innovative synergistic regulation strategy that integrated 2-amino-2-methyl-1-propanol (AMP) and n-propanol (NPA). Accordingly, a novel tertiary tetraethylenepentamine (TEPA)-AMP-NPA (T-A-N) NAA was devised. The optimized T-A-N maintained complete homogeneity throughout the entire CO2 absorption process and achieved an impressive CO2 loading of 1.15 mol·mol−1 while maintaining a low viscosity of merely 22.47 mPa·s. Remarkably, its absorption capacity showed little decrement after four consecutive absorption-desorption cycles, underscoring its exceptional recyclability. Within the T-A-N system, AMP underwent a reaction with CO2, yielding AMP-carbamate and protonated AMP, while TEPA engaged in CO2 absorption to form zwitterionic carbamates. During the desorption process, NPA served as a regeneration activator, facilitating the conversion of stable TEPA-carbamates into less stable alkyl carbonate intermediates, thereby enhancing the T-A-N's regeneration performance. Moreover, the T-A-N system addressed the issue of TEPA-carbamate self-aggregation into insoluble gelatinous substances by leveraging the synergistic enhancement effects between AMP derivatives and NPA. Specifically, these components effectively bound TEPA-carbamate species via robust electrostatic affinity and intermolecular hydrogen-bond interactions, inhibiting their self-aggregation and preventing the formation of insoluble products. Furthermore, T-A-N exhibited a significant reduction in both sensible and latent heat requirements, by 67 % and 82 % respectively, compared to 30 wt% MEA, highlighting its advantageous energy-saving potential for CO2 capture. Overall, harnessing the synergistic enhancement effects of AMP and NPA was conducive to the development of polyamine-based NAAs that offered superior CO2 capture reversibility, low energy consumption, and resistance to insoluble product formation.

Size-controllable tin oxide (SnO2) quantum dots (QDs) in aqueous solution were prepared by using stannous chloride and thiourea as source materials and the hydrothermal treatment was employed for size control during the self-assembly of SnO2 QDs. The size effects on structural and optical properties of QDs were discussed. The prepared QDs were confirmed to be of rutile structure with (2 0 2), (2 1 1) and (3 3 0) facets observed. The crystal lattice constants changed their dimensions during grain growth and secondary grain boundaries appeared if grain size was over 7 nm. The composition and valence states were found independent with grain size. A negative correlation was observed between size and band gap, which exhibited much greater values than the calculation results from the theory of effective mass approximation and illustrated a strong quantum confinement in the present SnO2 QDs. The size effect of photoluminescence property illustrated a fluorescence inhibition, which could be ascribed to the additional energy levels provided by the lattice distortions at secondary grain boundaries. The depletion region in QDs was extended by these defects, which strengthened the quantum confinement effect.

Formaldehyde (CHOH), a common volatile organic compound, causes many adverse effects on human health. The highly exposed TiO2(001) facet possesses a high photodegradation efficiency of CHOH due to its excellent ability to trap photogenerated holes and high density of surface unsaturated Ti atoms (Ti5c) to bind CHOH. However, the rapid recombination of photoinduced electron-hole pairs of TiO2(001) limits the photodegradation efficiency. We adopted a strategy of decorating TiO2(001) with g-C3N4 quantum dots (QDs), exploiting the quantum effect of g-C3N4QDs and their combined staggered band structure. This decoration improves the photocatalytic activity of TiO2(001). Moreover, the chemical configuration of g-C3N4QDs/TiO2(001) and the combination mode between the g-C3N4QDs and TiO2(001) support were explored in detail using high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations. Following the physiochemical characteristic results, the transport mechanism of photoinduced carriers was further analyzed by ultraviolet photoelectron spectroscopy (UPS), electron paramagnetic resonance (EPR), and Heyd-Scuseria-Ernzerh (HSE) exchange-correlation functional calculations. Finally, the performance and reaction mechanism of the photodegradation of CHOH by TiO2(001) and g-C3N4QDs/TiO2(001) were thoroughly investigated. The results show that the g-C3N4QDs were composed of an N-defect tri-s-triazine supported by TiO2(001) via a strong C-O-Ti chemical bond, which accelerated the separation of photoinduced carriers through a Z-scheme route. The photodegradation and mineralization efficiencies of CHOH were significantly promoted by 30% and 60% for g-C3N4QDs/TiO2(001) compared with those of TiO2(001). The photodegradation mechanism proceeded as CHOH - dioxymethylene - formate - carbonate - CO2. This study provides a surface engineering means to design highly active modified TiO2 for CHOH photodegradation.

The thickness effect on ultraviolet, visible and near-infrared (UV–Vis-NIR) light absorption of Mo-modified tin oxide (SnO2) thin films is investigated by the first principle calculation based on the density functional theory. The electronic structures and optical properties of the pristine, defective, Mo-doped and Mon (n = 1, 2, 3, 4) cluster adsorbed SnO2 (110) surfaces with film thickness from 0.594 to 3.273 nm are discussed. The results show that the pristine SnO2 semiconductor thin films can hardly absorb the Vis-NIR light. The absorption peaks in the Vis-NIR light region of the defective SnO2 (110) surface increase with the film thickness. The Vis-NIR light absorption of SnO2 is significantly enhanced by Mo modification. Mon cluster adsorption on SnO2 makes the greatest enhancement in Vis-NIR light absorption. The surface modification of Mo is concluded to be a promising route for SnO2 semiconductor thin film as a photocatalyst under Vis-NIR light irradiation.

Loss-of-function studies in human pluripotent stem cells (hPSCs) require efficient methodologies for lesion of genes of interest. Here, we introduce a donor-free paired gRNA-guided CRISPR/Cas9 knockout strategy (paired-KO) for efficient and rapid gene ablation in hPSCs. Through paired-KO, we succeeded in targeting all genes of interest with high biallelic targeting efficiencies. More importantly, during paired-KO, the cleaved DNA was repaired mostly through direct end joining without insertions/deletions (precise ligation), and thus makes the lesion product predictable. The paired-KO remained highly efficient for one-step targeting of multiple genes and was also efficient for targeting of microRNA, while for long non-coding RNA over 8 kb, cleavage of a short fragment of the core promoter region was sufficient to eradicate downstream gene transcription. This work suggests that the paired-KO strategy is a simple and robust system for loss-of-function studies for both coding and non-coding genes in hPSCs.

This paper presents a framework for addressing normative accounting issues for reporting to shareholders. The framework is an alternative to the emerging Conceptual Framework of the International Accounting Standards Board and the Financial Accounting Standards Board. The framework can be broadly characterized as a utilitarian approach to accounting standard setting. It has two main features. First, accounting is linked to valuation models under which shareholders use accounting information to values their stakes. Second, the desirable characteristics of accounting information are inferred from the demand of investors and analysts who use the information in practice. This stands in contrast to the “qualitative characteristics” in the Boards’ Framework which are embraced largely on the basis of their aesthetic appeal. These features lead to a set of broad accounting principles that resolve “recognition” and “measurement” issues at the core of the Boards’ Conceptual Framework and also the central issue of a balance sheet approach versus an income statement approach. The framework in the paper also frames the research questions for researchers interested in accounting policy.

Chinese listed firms are characterized by a great magnitude of long-duration accounts receivable from controlling shareholders and their affiliates, and they often do not make bad debt allowances. On many occasions, these receivables are never collected. We find that firms with a great magnitude of accounts receivable demonstrate a low level of future profitability and low stock returns. It does not appear that the low earnings persistence of these firms is responsible for their poor future performance as predicted by the accrual anomaly, because the firms also report low concurrent earnings. In the context of the Chinese stock market, we interpret the results as being consistent with self-dealing through trade credit by controlling shareholders. This study contributes to the self-dealing literature by identifying a more subtle channel of expropriation of minority shareholders in China.