CH3NH3PbI3 is a hybrid organic-inorganic material with a perovskite structure and a temperature-dependent polymorphism whose origins are still unclear. Here we perform ab initio molecular dynamics simulations in order to investigate the structural properties and atom dynamics of CH3NH3PbI3 at room temperature. Starting from different initial configurations, we find that a single-crystalline system undergoes a spontaneous ordering process which brings the CH3NH3(+) ions to alternately point towards the center of two out of the six faces of the cubic PbI3(-) framework, i.e. towards the 〈100〉 and 〈010〉 directions. This bidirectional ordering gives rise to a preferential distortion of the inorganic lattice on the a-b plane, shaping the observed tetragonal symmetry of the system. The process requires tens of picoseconds for CH3NH3PbI3 supercells with just eight CH3NH3(+) ions.
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http://dx.doi.org/10.1038/srep24443 | DOI Listing |
Front Neurol
December 2024
Key Laboratory of Oral Diseases Research of Anhui Province, College & Hospital of Stomatology, Anhui Medical University, Hefei, China.
Background: The causal relationship between hypothyroidism and obstructive sleep apnea (OSA) remains controversial. Therefore, our research used a bidirectional Mendelian randomization (MR) method in an attempt to determine the causal relationship between hypothyroidism and OSA.
Methods: From the publicly accessible genome-wide association analysis (GWAS) summary database, we obtained single nucleotide polymorphism (SNPs) data pertaining to hypothyroidism and OSA.
Front Plant Sci
December 2024
College of Agronomy, College of Mechanical and Electronic Engineering, Shandong Agricultural University, Taian, Shandong, China.
In order to achieve precise discrimination of leaf diseases in the Maize/Soybean intercropping system, i.e. leaf spot disease, rust disease, mixed leaf diseases, this study utilized hyperspectral imaging and deep learning algorithms for the classification of diseased leaves of maize and soybean.
View Article and Find Full Text PDFComput Biol Med
December 2024
College of Food and Biological Engineering, Chengdu University, Chengdu, 610106, China; Country Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Chengdu, 610106, China.
Thermophilic proteins, mesophiles proteins and psychrophilic proteins have wide industrial applications, as enzymes with different optimal temperatures are often needed for different purposes. Convenient methods are needed to determine the optimal temperatures for proteins; however, laboratory methods for this purpose are time-consuming and laborious, and existing machine learning methods can only perform binary classification of thermophilic and non-thermophilic proteins, or psychrophilic and non-psychrophilic proteins. Here, we developed a deep learning model, PSTP-BERT, based on protein sequences that can directly perform Three classes identification of thermophilic, mesophilic, and psychrophilic proteins.
View Article and Find Full Text PDFSmall
December 2024
School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
Plasmonic metasurfaces (PMs) exhibit extraordinary optical response due to surface lattice resonance, which is crucial for realizing high-performance photovoltaic device preparation. In this work, a nanopore confinement effect-mediated MOF@UsAu is proposed as a novel PM heterojunction for photovoltaic interfaces. 2D MOFs have the unique advantage of a tunable and ordered porous structure.
View Article and Find Full Text PDFComput Methods Programs Biomed
December 2024
Department of Computer Science and Engineering, School of Computing, SASTRA Deemed to be University, Thanjavur, Tamilnadu, 613402, India.
Objective: Social communication difficulties are a characteristic of autism spectrum disorder (ASD), a neurodevelopmental condition. The earlier method of diagnosing autism largely relied on error-prone behavioral observation of symptoms. More intelligence approaches are in progress to diagnose the disorder, which still demands improvement in prediction accuracy.
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