Flexibly serving a finite number of heterogeneous jobs in a tandem system

Ministry of Education, Singapore under its Academic Research Funding Tier

Quantum algorithms for optimal effective theory of many-body systems

A common situation in quantum many-body physics is that the underlying theories are known but too complicated to solve efficiently. In such cases, one usually builds simpler effective theories as low-energy or large-scale alternatives to the original theories. Here the central tasks are finding the optimal effective theories among a large number of candidates and proving their equivalence to the original theories. Recently quantum computing has shown the potential of solving quantum many-body systems by exploiting its inherent parallelism. It is thus an interesting topic to discuss the emergence of effective theories and design efficient tools for finding them based on the results from quantum computing. As the first step towards this direction, in this paper, we propose two approaches that apply quantum computing to find the optimal effective theory of a quantum many-body system given its full Hamiltonian. The first algorithm searches the space of effective Hamiltonians by quantum phase estimation and amplitude amplification. The second algorithm is based on a variational approach that is promising for near-future applications.Comment: 8 pages, 4 figure

Good learning environment of medical schools is an independent predictor for medical students’ study engagement

BackgroundStudy engagement is regarded important to medical students’ physical and mental wellbeing. However, the relationship between learning environment of medical schools and the study engagement of medical students was still unclear. This study was aimed to ascertain the positive effect of learning environment in study engagement.MethodsWe collected 10,901 valid questionnaires from 12 medical universities in China, and UWES-S was utilized to assess the study engagement levels. Then Pearson Chi-Square test and Welch’s ANOVA test were conducted to find the relationship between study engagement and learning environment, and subgroup analysis was used to eradicate possible influence of confounding factors. After that, a multivariate analysis was performed to prove learning environment was an independent factor, and we constructed a nomogram as a predictive model.ResultsWith Pearson Chi-Square test (p < 0.001) and Welch’s ANOVA test (p < 0.001), it proved that a good learning environment contributed to a higher mean of UWES scores. Subgroup analysis also showed statistical significance (p < 0.001). In the multivariate analysis, we could find that, taking “Good” as reference, “Excellent” (OR = 0.329, 95%CI = 0.295–0.366, p < 0.001) learning environment was conducive to one’s study engagement, while “Common” (OR = 2.206, 95%CI = 1.989–2.446, p < 0.001), “Bad” (OR = 2.349, 95%CI = 1.597–3.454, p < 0.001), and “Terrible” (OR = 1.696, 95%CI = 1.015–2.834, p = 0.044) learning environment only resulted into relatively bad study engagement. Depending on the result, a nomogram was drawn, which had predictive discrimination and accuracy (AUC = 0.680).ConclusionWe concluded that learning environment of school was an independent factor of medical student’s study engagement. A higher level of learning environment of medical school came with a higher level of medical students’ study engagement. The nomogram could serve as a predictive reference for the educators and researchers

Multidimensionally constrained relativistic Hartree-Bogoliubov study of spontaneous nuclear fission

Background: Recent microscopic studies, based on the theoretical framework of nuclear energy density functionals, have analyzed dynamic (least action) and static (minimum energy) fission paths, and it has been shown that in addition to the important role played by nonaxial and/or octupole collective degrees of freedom, fission paths crucially depend on the approximations adopted in calculating the collective inertia.Purpose: To analyze effects of triaxial and octupole deformations, as well as approximations to the collective inertia, on the symmetric and asymmetric spontaneous fission dynamics, and compare with results of recent studies based on the self-consistent Hartree-Fock-Bogoliubov (HFB) method.Methods: Deformation energy surfaces, collective potentials, and perturbative and nonperturbative cranking collective inertia tensors are calculated using the multidimensionally-constrained relativistic Hartree-Bogoliubov (MDC-RHB) model, with the energy density functionals PC-PK1 and DD-PC1. Pairing correlations are treated in the Bogoliubov approximation using a separable pairing force of finite range. The least-action principle is employed to determine dynamic spontaneous fission paths.Results: The dynamics of spontaneous fission of Fm264 and Fm250 is explored. The fission paths, action integrals, and the corresponding half-lives predicted by the functionals PC-PK1 and DD-PC1 are compared and, in the case of Fm264, discussed in relation with recent results obtained using the HFB model based on the Skyrme functional SkM∗ and a density dependent mixed pairing interaction.Conclusions: The inclusion of nonaxial quadrupole and octupole shape degrees of freedom is essential for a quantitative analysis of fission dynamics. The action integrals and, consequently, the half-lives crucially depend on the approximation used to calculate the effective collective inertia along the fission path. The perturbative cranking approach underestimates the effects of structural changes at the level crossings and the resulting collective inertia varies relatively smoothly in the (β20,β22) and (β20,β30) planes. In contrast, the nonperturbative collective mass is characterized by the occurrence of sharp peaks on the surface of collective coordinates, that can be related to single-particle level crossings near the Fermi surface. This enhances the effective inertia, increases the values of the action integral, and results in longer fission half-lives

Does Host-Guest Interaction Stimulate Tourists’ Citizenship Behavior? A Combination of Social Exchange Theory and Cognitive Appraisal Theory

This study delved into the intricate ways in which host-guest interaction influences tourist citizenship behavior (TCB), focusing specifically on two key dimensions: interaction quantity and interaction quality. By drawing on social exchange theory and cognitive appraisal theory, we constructed an integrated model that illustrates the relationship between host-guest interaction and TCB, with experiential value and place attachment serving as mediating factors. Our data were gathered from 499 visitors to Mount Taishan national forest park, and the analysis was conducted using Spss and Amos software. The results revealed that the quality of host-guest interaction has a significant and positive influence on tourists’ overall experiential value, which in turn fosters TCB. Additionally, the evaluation of experiential value triggers a deeper sense of place attachment among tourists towards the destination, further encouraging TCB. The quantity of host-guest interaction did not exert a significant influence on tourist citizenship behavior. These findings offer practical insights for destinations seeking to enhance their competitiveness and sustainability by optimizing host-guest interactions

Study on the Influence of Host–Guest Interaction on Tourists’ Pro-Environment Behavior: Evidence from Taishan National Forest Park in China

This study explores the influence of host–guest interaction on tourists’ pro-environment behavior. On the one hand, the experience attribute of host–guest interaction’s influence on tourists’ experiential value is sorted out. On the other hand, the relationship attribute of host–guest interaction’s activation effect on tourists’ personal norms is identified. Based on social exchange theory and normative activation theory, a structural equation model was established to depict the transmission mechanism from host–guest interaction to tourists’ pro-environment behavior. The data were collected from tourists in Taishan National Forest Park (n = 499). The results indicated that host–guest interaction quality activated tourists’ personal norms through consequence awareness, thus promoting tourists’ pro-environment behavior. Meanwhile, the quality of host–guest interaction positively influenced tourists’ pro-environment behavior through emotional experience value. Host–guest interaction quantity promoted tourists’ pro-environment behavior by activating personal norms through responsibility ascription. In addition, although frequent host–guest interactions can enhance the social experience and functional experience value of tourists, the latter two cannot stimulate tourists’ pro-environmental behavior. This study provides practical implications for promoting the sustainable development of national forest parks

Superdeformed Λ\Lambda hypernuclei within relativistic mean field models

We study the superdeformed (SD) states and corresponding SD hypernuclei of Ar isotopes with the multidimensionally constrained relativistic mean field (MDC-RMF) models, which can accommodate various shape degree of freedom. We found that the density profiles of SD states in Ar isotopes show a strong localization with a ring structure near the surface, while the central part of the density is dilute, showing a hole structure. This localization of SD density induces an appreciable deformation in the hyperon wave function and results in a large overlap between the core and the hyperon in the SD hypernuclei of Ar isotopes. Then the Λ separation energy of the SD state becomes larger than that of a normally deformed or spherical ground state. This feature is different from that found in other nuclei such as 32S, 56Ni, and 60Zn in which the Λ separation energy of larger deformed state is smaller. In this context, the measurement of the Λ separation energy may provide important information on the localization of the density profile of SD states

Appointment-driven queueing systems with non-punctual customers

International audienc

Pharmacognostical study of Sterculia monosperma fruit

Sterculia monosperma fruit is the dried and mature seed of Sterculia monosperma, which belongs to genus Sterculia. In China, this plant is a widely distributed arbor with a long planting history in Lingnan area. It is mainly cultivated in Guangdong, Guangxi, Fujian, Yunnan and Taiwan of China; it is also distributed in India, Vietnam and Indonesia, mostly cultivated artificially. S. monosperma fruit has many functions like warming the stomach and killing pests, but its name and characteristics are easily confused with other plants of genus Sterculia. However, the relevant research foundation is relatively weak. Pharmacognostical study can provide reference for its resource development and quality standard formulation. This study identifies the morphological and microscopic characteristics of S. monosperma fruit, as well as the microscopic identification of seed cross-section and powder. The DNA barcode sequences ITS2, psbA-trnH, matK and rbcL of S. monosperma were obtained through bidirectional sequencing, Kimura 2-Parameter (K2P) genetic distance was calculated, and the neighbor joining tree was established for clustering analysis. The results were as follows: (1) The morphological characteristics of S. monosperma fruit included dark red fruit shell and reddish brown or dark chestnut surface. It was hard in texture, with two thick yellowish endosperms inside. (2) The micro-morphological characteristics was that the exotesta was reddish brown, extremely thin, and brittle in texture; the mesotesta was black brown, thick, and hard in texture; the endotesta coat was light yellow and soft in texture. (3) The microscopic characteristics included the structure and arrangement of the exotesta stone cell, the grid cell structure of the mesotesta, the bead thickening of the cell wall of the endotesta cells, and the calcium oxalate cluster crystals. (4) Based on the ITS2 sequence, S. monosperma fruit could be effectively distinguished from other plants in genus Sterculia, while the matK sequence could effectively distinguish S. lanceolata from other plants in genus Sterculia. This study obtained the data on the morphological characteristics, micro-morphological characteristics and microscopic characteristics of S. monosperma fruit. Combined with the ITS2 barcode sequence, S. monosperma fruit can be effectively identified, which provides a scientific reference for the development of its germplasm resources and the formulation of relevant quality standards

Transcriptomic analysis of Perilla frutescens seed to insight into the biosynthesis and metabolic of unsaturated fatty acids

Abstract Background Perilla frutescens is well known for its high α-linolenic acid (ALA) accumulation in seeds and medicinal values as well as a source of edible and general-purpose oils. However, the regulatory mechanisms of the biosynthesis of fatty acid in its seeds remain poorly understood due to the lacking of sequenced genome. For better understanding the regulation of lipid metabolism and further increase its oil content or modify oil composition, time-course transcriptome and lipid composition analyses were performed. Results Analysis of fatty acid content and composition showed that the α-linolenic acid and oleic acid accumulated rapidly from 5 DAF to 15 DAF and then kept relatively stable. However, the amount of palmitic acid and linoleic acid decreased quickly from 5 DAF to 15DAF. No significant variation of stearic acid content was observed from 5 DAF to 25DAF. Our transcriptome data analyses revealed that 110,176 unigenes were generated from six seed libraries at 5, 10, 20 DAF. Of these, 53 (31 up, 22 down) and 653 (259 up, 394 down) genes showed temporal and differentially expression during the seed development in 5 DAF vs 10 DAF, 20 vs 10 DAF, respectively. The differentially expressed genes were annotated and found to be involved in distinct functional categories and metabolic pathways. Deep mining of transcriptome data led to the identification of key genes involved in fatty acid and triacylglycerol biosynthesis and metabolism. Thirty seven members of transcription factor family AP2, B3 and NFYB putatively involved in oil synthesis and deposition were differentially expressed during seed development. The results of qRT-PCR for selected genes showed a strong positive correlation with the expression abundance measured in RNA-seq analysis. Conclusions The present study provides valuable genomic resources for characterizing Perilla seed gene expression at the transcriptional level and will extend our understanding of the complex molecular and cellular events of oil biosynthesis and accumulation in oilseed crops