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This study presents a parallel algorithm for high-dimensional quantum dynamics simulations in poly atomic reactions, integrating distributed- and shared-memory models. The distributions of the wave function and potential energy matrix across message passing interface processes are based on bundled radial and angular dimensions, with implementations featuring either two- or one-sided communication schemes. Using realistic parameters for the H + NH3 reaction, performance assessment reveals linear scalability, exceeding 90% efficiency with up to 600 processors. In addition, owing to the universal and concise structure, the algorithm demonstrates remarkable extensibility to diverse reaction systems, as demonstrated by successes with six-atom and four-atom reactions. This work establishes a robust foundation for high-dimensional dynamics studies, showcasing the algorithm's efficiency, scalability, and adaptability. The algorithm's potential as a valuable tool for unraveling quantum dynamics complexities is underscored, paving the way for future advancements in the field. [ABSTRACT FROM AUTHOR]

The widespread adoption of the power grid has led to increased attention to load frequency control (LFC) in power systems. The LFC strategy of multi-source hybrid power systems, including hydroelectric generators, Wind Turbine Generators (WTGs), and Photovoltaic Generators (PVGs), with thermal generators is more challenging. Existing methods for LFC tasks pose challenges in achieving satisfactory outcomes in hybrid power systems. In this paper, a novel method for the multi-source hybrid power system LFC task by using an optimal active disturbance rejection control (ADRC) strategy is proposed, which is based on the combination of the improved linear quadratic regulator (LQR) and the ADRC controller. Firstly, an established model of a hybrid power system is presented, which incorporates multiple regions and multiple sources. Secondly, utilizing the state space representation, a novel control strategy is developed by integrating improved LQR and ARDC. Finally, a series of comparative simulation experiments has been conducted using the Simulink model. Compared with the LQR with ESO, the maximum relative error of the maximum peaks of frequency deviation and tie-line exchanged power of the hybrid power system is reduced by 96% and 83%, respectively, by using the proposed strategy. The experimental results demonstrate that the strategy proposed in this paper exhibits a substantial enhancement in control performance. [ABSTRACT FROM AUTHOR]

Complex human traits are influenced by variation in regulatory DNA through mechanisms that are not fully understood. Because regulatory elements are conserved between humans and mice, a thorough annotation of cis regulatory variants in mice could aid in further characterizing these mechanisms. Here we provide a detailed portrait of mouse gene expression across multiple tissues in a three-way diallel. Greater than 80% of mouse genes have cis regulatory variation. Effects from these variants influence complex traits and usually extend to the human ortholog. Further, we estimate that at least one in every thousand SNPs creates a cis regulatory effect. We also observe two types of parent-of-origin effects, including classical imprinting and a new global allelic imbalance in expression favoring the paternal allele. We conclude that, as with humans, pervasive regulatory variation influences complex genetic traits in mice and provide a new resource toward understanding the genetic control of transcription in mammals.

A general Bayesian model, Diploffect, is described for estimating the effects of founder haplotypes at quantitative trait loci (QTL) detected in multiparental genetic populations; such populations include the Collaborative Cross (CC), Heterogeneous Socks (HS), and many others for which local genetic variation is well described by an underlying, usually probabilistically inferred, haplotype mosaic. Our aim is to provide a framework for coherent estimation of haplotype and diplotype (haplotype pair) effects that takes into account the following: uncertainty in haplotype composition for each individual; uncertainty arising from small sample sizes and infrequently observed haplotype combinations; possible effects of dominance (for noninbred subjects); genetic background; and that provides a means to incorporate data that may be incomplete or has a hierarchical structure. Using the results of a probabilistic haplotype reconstruction as prior information, we obtain posterior distributions at the QTL for both haplotype effects and haplotype composition. Two alternative computational approaches are supplied: a Markov chain Monte Carlo sampler and a procedure based on importance sampling of integrated nested Laplace approximations. Using simulations of QTL in the incipient CC (pre-CC) and Northport HS populations, we compare the accuracy of Diploffect, approximations to it, and more commonly used approaches based on Haley-Knott regression, describing trade-offs between these methods. We also estimate effects for three QTL previously identified in those populations, obtaining posterior intervals that describe how the phenotype might be affected by diplotype substitutions at the modeled locus.

MotivationRNA-Seq technique has been demonstrated as a revolutionary means for exploring transcriptome because it provides deep coverage and base pair-level resolution. RNA-Seq quantification is proven to be an efficient alternative to Microarray technique in gene expression study, and it is a critical component in RNA-Seq differential expression analysis. Most existing RNA-Seq quantification tools require the alignments of fragments to either a genome or a transcriptome, entailing a time-consuming and intricate alignment step. To improve the performance of RNA-Seq quantification, an alignment-free method, Sailfish, has been recently proposed to quantify transcript abundances using all k-mers in the transcriptome, demonstrating the feasibility of designing an efficient alignment-free method for transcriptome quantification. Even though Sailfish is substantially faster than alternative alignment-dependent methods such as Cufflinks, using all k-mers in the transcriptome quantification impedes the scalability of the method.ResultsWe propose a novel RNA-Seq quantification method, RNA-Skim, which partitions the transcriptome into disjoint transcript clusters based on sequence similarity, and introduces the notion of sig-mers, which are a special type of k-mers uniquely associated with each cluster. We demonstrate that the sig-mer counts within a cluster are sufficient for estimating transcript abundances with accuracy comparable with any state-of-the-art method. This enables RNA-Skim to perform transcript quantification on each cluster independently, reducing a complex optimization problem into smaller optimization tasks that can be run in parallel. As a result, RNA-Skim uses 100 speedup over the state-of-the-art alignment-based methods, while delivering comparable or higher accuracy.Availability and implementationThe software is available at http://www.csbio.unc.edu/rs.

Metal‐halide perovskites (MHPs) are promising as active optoelectronic materials for a diverse range of devices. Anion exchange is a post‐growth modification of MHP materials that allows tuning of the band gap and crystal structure by exposure to alternative halides, normally using solution methods. Here, low temperature gas‐phase anion exchange for the conversion of CsPbBr3 nanowires (NW) into CsPb(Br1−xClx) NWs using two media, fuming HCl and Cl2 gas, is systematically investigated. It is found that both methods can be used to tune the composition in the full range with excellent control. While fuming HCl is the simplest process, Cl2 gives similar results with no surface damage and better process control. Based on a simple solid diffusion model, an average diffusivity of 1.4 × 10−12 cm2s−1 is extracted for Cl‐anions inside CsPbBr3. By combining the Cl2 exchange process with electron‐beam lithography patterning, heterojunction NWs with varying halide compositions are produced, including complex barcode‐like NWs with segment lengths as short as 500 nm. Designed heterostructures provide an important basis for optoelectronic device applications of MHPs, and gas‐phase anion exchange should be suitable for any MHP morphology. [ABSTRACT FROM AUTHOR]

Quantum interference between reaction pathways around a conical intersection (CI) is an ultrasensitive probe of detailed chemical reaction dynamics. Yet, for the hydrogen exchange reaction, the difference between contributions of the two reaction pathways increases substantially as the energy decreases, making the experimental observation of interference features at low energy exceedingly challenging. We report in this paper a combined experimental and theoretical study on the H + HD → H2 + D reaction at the collision energy of 1.72 eV. Although the roaming insertion pathway constitutes only a small fraction (0.088%) of the overall contribution, angular oscillatory patterns arising from the interference of reaction pathways were clearly observed in the backward scattering direction, providing direct evidence of the geometric phase effect at an energy of 0.81 eV below the CI. Furthermore, theoretical analysis reveals that the backward interference patterns are mainly contributed by two distinct groups of partial waves (J ~ 10 and J ~ 19). The well-separated partial waves and the geometric phase collectively influence the quantum reaction dynamics. In a combined experimental and theoretical study of the H + HD → H2 + D reaction at low collision energy (1.72 eV), the authors obtain detailed information on the quantum reaction dynamics surrounding a conical intersection. [ABSTRACT FROM AUTHOR]

Talents are the most important factor of all in the efforts to establish an innovative country. In universities and colleges, the bases for talent cultivation, the turnover of teachers in an explicit or recessive way calls for our urgent attention. This article aims at analyzing the complex causes of college teachers' turnover from the perspective of institutional economics including Limitation of Incentive Theory, Interests Relative Theory and Principal-Agent Theory. Besides, it puts forward some relevant measures to solve the current problem.

A full-dimensional ab initio potential energy surface (PES) and dipole moment surface (DMS) for the ammonia dimer (NH3)2 are reported. The database of the PES consists of 27 736 ab initio energy points and all of these points were calculated at the UCCSD(T)-F12a/AVTZ level. The PES was fitted by using the fundamental invariant neural network (FI-NN) method that satisfies the permutational symmetry of identical atoms, and the root mean square fitting error for the PES is very small as low as 0.562 meV. The geometries for the (NH3)2 DMS are the same as those used for the PES and are calculated at the XYG3/AVTZ level. This PES can describe a variety of internal floppy motions, including all kinds of vibrational modes no matter intermolecular or intramolecular. The CCSD(T)-PES can dissociate correctly to two NH3 monomers, with De = 1135.55 cm−1 (13.58 kJ/mol) which agrees accurately with the 13.5 ± 0.3 kJ/mol predicted by previous work. [ABSTRACT FROM AUTHOR]

A full-dimensional ab initio potential energy surface (PES) and dipole moment surface (DMS) for the ammonia dimer (NH3)2 are reported. The database of the PES consists of 27 736 ab initio energy points and all of these points were calculated at the UCCSD(T)-F12a/AVTZ level. The PES was fitted by using the fundamental invariant neural network (FI-NN) method that satisfies the permutational symmetry of identical atoms, and the root mean square fitting error for the PES is very small as low as 0.562 meV. The geometries for the (NH3)2 DMS are the same as those used for the PES and are calculated at the XYG3/AVTZ level. This PES can describe a variety of internal floppy motions, including all kinds of vibrational modes no matter intermolecular or intramolecular. The CCSD(T)-PES can dissociate correctly to two NH3 monomers, with De = 1135.55 cm−1 (13.58 kJ/mol) which agrees accurately with the 13.5 ± 0.3 kJ/mol predicted by previous work. [ABSTRACT FROM AUTHOR]

The Kaiser effect in rock acoustic emission (AE) test is the most direct manifestation of rock memory function. This article focuses on the influence of different deformation stages and different historical stress conditions on stress memory function, and conducts AE testing of rock-like specimens. It explained the stress memory function in AE testing from the perspectives of crack propagation and damage accumulation. The crack initiation stress σ ci and crack damage stress σ cd of specimens were obtained based on the stress-strain curve method, and the different deformation stages were divided. The damage evolution coefficient D e was proposed to measure the size of the stable development range of damage based on the normalized crack initiation and crack damage stress. The historical stress in the elastic stage could be easily identified from the Kaiser effect during the reloading process, even if the time interval reached 120 hours. The Felicity effect appeared during the reloading process when the historical stress was in the stage of stable crack propagation, and the FR value showed a decreasing trend with the extension of the time interval between loading tests. The loading history in the elastic stage was a training for the AE stress memory function under complex historical stress conditions, which restored the Kaiser effect in the stage of stable crack propagation. The distribution of AE events and CT scanning results were also analyzed in the article, and the damage accumulation information characterized by both are basically consistent. The double Kaiser effect phenomenon appeared in the AE test under complex historical stress conditions, although the criterion for discriminating the AE signal at the Kaiser effect point corresponding to the lower stress remained to be further studied and verified. [ABSTRACT FROM AUTHOR]