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The considerable thermal expansion of halide perovskites is one of the challenges to device stability, yet the physical origin and modulation strategy remain unclear. Herein, we report first-principles calculations of the thermal properties of halide perovskites at 300 K using oxides as a reference. We found that the large thermal expansion of halide perovskites can mainly be attributed to their low bulk modulus and volumetric heat capacity because of the soft crystal lattice, whereas composition-dependent anharmonicity emerges as the most important factor in determining thermal expansion with the same structure. We discovered that thermal expansion of halide perovskites can be decreased by weakening the B-X bond to promote the octahedral anharmonicity. We further proposed an effective thermal expansion coefficient descriptor of halide perovskites with a Pearson correlation coefficient of nearly -80%. Our findings provide insights into the underlying mechanisms and chemical trends in the thermal expansion behavior of halide perovskites.

To evaluate the blink reflex (BR) in estimating the potential injury of trigeminal nerve following percutaneous balloon compression (PBC) surgery, and to determine the association between BR alterations and early surgical outcomes.In this single-center, prospective before-and-after study, a total of 74 patients who had primary trigeminal neuralgia and scheduled for PBC between October 2020 and June 2021 were prospectively included. BR testing and facial sensory assessment were performed pre- and post-PBC. The latency and the area under the curve (AUC) of pre- and postoperative R1 (R1The BR components were noticeably delayed or diminished following PBC. R1Both R1 and R2 were significantly diminished after PBC and these alterations were associated with early surgical outcomes, suggesting that the BR is useful in evaluating trigeminal injury following PBC and could provide objective information about early prognosis.

Effective modification of the structure and properties of halide perovskites via the pressure engineering strategy has attracted enormous interest in the past decade. However, sufficient effort and insights regarding the potential properties and applications of the high-pressure amorphous phase are still lacking. Here, the superior and tunable photoelectric properties that occur in the pressure-induced amorphization process of the halide perovskite Cs

Photoelectric devices based on the photothermoelectric (PTE) effect show promising prospects for broadband detection without an external power supply. However, effective strategies are still required to regulate the conversion efficiency of light to heat and electricity. Herein, significantly enhanced photoresponse properties of PbI

The title compound, C24H19NO, was obtained via the reaction of (1E,2E)-3-(3-methoxyphenyl)-1-phenylprop-2-en-1-one with ethyl 2-oxopropanoate, using NH4I as a catalyst. The compound crystallizes in the monoclinic space group I2/a. In the molecule, the four rings are not in the same plane, the pyridine ring being inclined to the benzene rings by 17.26 (6), 56.16 (3) and 24.50 (6)°. In the crystal, molecules are linked by C—H...π interactions into a three-dimensional network. To further analyse the intermolecular interactions, a Hirshfeld surface analysis was performed. Hirshfeld surface analysis indicates that the most abundant contributions to the crystal packing are from H...H (50.4%), C...H/H...C (37.9%) and O...H/H...O (5.1%) interactions.

Open framework structures (e.g., ScF3, Sc2W3O12, etc.) exhibit significant potential for thermal expansion tailoring owing to their high atomic vibrational degrees of freedom and diverse connectivity between polyhedral units, displaying positive/negative thermal expansion (PTE/NTE) coefficients at a certain temperature. Despite the proposal of several physical mechanisms to explain the origin of NTE, an accurate mapping relationship between the structural–compositional properties and thermal expansion behavior is still lacking. This deficiency impedes the rapid evaluation of thermal expansion properties and hinders the design and development of such materials. We developed an algorithm for identifying and characterizing the connection patterns of structural units in open-framework structures and constructed a descriptor set for the thermal expansion properties of this system, which is composed of connectivity and elemental information. Our developed descriptor, aided by machine learning (ML) algorithms, can effectively learn the thermal expansion behavior in small sample datasets collected from literature-reported experimental data (246 samples). The trained model can accurately distinguish the thermal expansion behavior (PTE/NTE), achieving an accuracy of 92%. Additionally, our model predicted six new thermodynamically stable NTE materials, which were validated through first-principles calculations. Our results demonstrate that developing effective descriptors closely related to thermal expansion properties enables ML models to make accurate predictions even on small sample datasets, providing a new perspective for understanding the relationship between connectivity and thermal expansion properties in the open framework structure. The datasets that were used to support these results are available on Science Data Bank, accessible via the link https://doi.org/10.57760/sciencedb.j00113.00100.

The rapid development of the semiconductor industry has motivated researchers passion for accelerating the discovery of advanced optoelectronic materials. Computational functionality‐driven design is an emerging branch of material science that has become effective at making material predictions. By combining advanced solid‐state knowledge and high‐throughput first‐principles computational approaches with intelligent algorithms plus database development, experts can now efficiently explore many novel materials by taking advantage of the power of supercomputer architectures. Here, we discuss a set of typical design strategies that can be used to accelerate inorganic optoelectronic materials discovery from computer simulations: In silico computational screening; knowledge‐based inverse design; and algorithm‐based searching. A few representative examples in optoelectronic materials design are discussed to illustrate these computational functionality‐driven modalities. Challenges and prospects for the computational functionality‐driven design of materials are further highlighted at the end of the review.

Although N6-methyladenosine (m6A) has been implicated in various biological functions in human cancers, its role in predicting the prognosis of glioma remains unclear. In this study, the transcriptome expression profiles and the clinical data of 961 patients were derived from the Chinese Glioma Genome Atlas (CGGA). We comprehensively evaluated the association between the expression of m6A regulators and the prognosis of glioma and established a 3-gene (YTHDF2, FTO, and ALKBH5) risk signature using least absolute shrinkage and selection operator (LASSO) analysis. Patients with a high-risk signature had significantly adverse prognoses. Gene set enrichment analysis (GSEA) analysis revealed that the G2M checkpoint, MTORC1 signaling, epithelial mesenchymal transition, and PI3K-AKT-mTOR signaling were significantly enriched in the high-risk group. Univariate and multivariate Cox regression analyses confirmed the independent prognostic value of this risk signature. We then constructed a nomogram for individualized prediction of overall survival (OS) by integrating clinicopathological features (age, World Health Organization [WHO] grade), treatment information (radiotherapy, temozolomide therapy), and m6A risk signature. The calibration curves showed excellent agreement between the predicted and actual probabilities for the 1-, 3-, and 5-year OS, with a C-index of 0.780 in the training cohort and 0.717 in the validation cohort. Altogether, our study elucidated the important role of m6A regulators in glioma prognosis, which is valuable for the selection of therapeutic methods and clinical management of patients with glioma.

Two-dimensional (2D) layered perovskites have emerged as potential alternates to traditional three-dimensional (3D) analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson (DJ) perovskites. In this work, a serious of cycloalkane (CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional (DFT) calculations. We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV. These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.

Organic–inorganic hybrid perovskites such as methylammonium lead iodide (MAPbI3) materials have recently attracted great attention due to their potential for photovoltaic applications. The performance and stability of these perovskite solar cells are sensitive to water and moisture in an ambient environment. Thus, an understanding of how water influences MAPbI3 and particularly the role of grain boundary (GB) defects is important for developing appropriate mitigation strategies. Herein, water molecular diffusion in ∑5‐(210) GB is investigated and compared with pristine MAPbI3 using first‐principles calculations. Water diffusion along the ∑5‐(210) GB is found to be facile with a 0.07 eV energy barrier while diffusion barrier from GB core to bulk is 0.24 eV. In contrast, the diffusion process in bulk MAPbI3 is relatively large 0.70 eV due to water interactions with the Pb–I network. Further, it is shown that water is more stable in the GB region compared with the pristine system. Thus, the strong thermodynamic and kinetic tendencies for water segregation to the GBs in MAPbI3 suggests that improving the crystallinity of MAPbI3 is an effective strategy to slow down water degradation processes in agreement with recent experimental results.