Lifshitz spacetimes, solitons, and generalized BTZ black holes in quantum gravity at a Lifshitz point

In this paper, we study static vacuum solutions of quantum gravity at a fixed Lifshitz point in (2+1) dimensions, and present all the diagonal solutions in closed forms in the infrared limit. The exact solutions represent spacetimes with very rich structures: they can represent generalized BTZ black holes, Lifshitz space-times or Lifshitz solitons, in which the spacetimes are free of any kind of space-time singularities, depending on the choices of the free parameters of the solutions. We also find several classes of exact static non-diagonal solutions, which represent similar space-time structures as those given in the diagonal case. The relevance of these solutions to the non-relativistic Lifshitz-type gauge/gravity duality is discussed.Comment: revtex4, 5 figures. Typos are correcte

What Drives Workers to Learn Online during COVID 19 Pandemics?

One of the common practices during the COVID-19 pandemic is to work or study from home. This study aims to reexamine the factors affecting individual continuance intention of e-learning. During the pandemic, via a survey conducted in 2022, we assessed workers’ continuance intention of e-learning from different sectors in Taiwan. This research brought motivations as mediators in continuance intention to e-learning. Through the statistical analysis, we identified the mediation effect of motivations based on the self-determination theory. The results show that autonomous motivation facilitates the learners’ computer self-efficacy, the quality of the system and content toward continuance intention; controlled motivation could mediate the monetary award in influencing the continuance intention. The internalization of motivation is also an effective mediator. The obtained results not only add new knowledge of what affected the continuance intention of e-learning during the pandemic but also provide guidance for employers to allocate resources to boost e-learning after the pandemic

Identification of gene-oriented exon orthology between human and mouse

<p>Abstract</p> <p>Background</p> <p>Gene orthology has been well studied in the evolutionary area and is thought to be an important implication to functional genome annotations. As the accumulation of transcriptomic data, alternative splicing is taken into account in the assignments of gene orthologs and the orthology is suggested to be further considered at transcript level. Whether gene or transcript orthology, exons are the basic units that represent the whole gene structure; however, there is no any reported study on how to build exon level orthology in a whole genome scale. Therefore, it is essential to establish a gene-oriented exon orthology dataset.</p> <p>Results</p> <p>Using a customized pipeline, we first build exon orthologous relationships from assigned gene orthologs pairs in two well-annotated genomes: human and mouse. More than 92% of non-overlapping exons have at least one ortholog between human and mouse and only a small portion of them own more than one ortholog. The exons located in the coding region are more conserved in terms of finding their ortholog counterparts. Within the untranslated region, the 5' UTR seems to have more diversity than the 3' UTR according to exon orthology designations. Interestingly, most exons located in the coding region are also conserved in length but this conservation phenomenon dramatically drops down in untranslated regions. In addition, we allowed multiple assignments in exon orthologs and a subset of exons with possible fusion/split events were defined here after a thorough analysis procedure.</p> <p>Conclusions</p> <p>Identification of orthologs at the exon level is essential to provide a detailed way to interrogate gene orthology and splicing analysis. It could be used to extend the genome annotation as well. Besides examining the one-to-one orthologous relationship, we manage the one-to-multi exon pairs to represent complicated exon generation behavior. Our results can be further applied in many research fields studying intron-exon structure and alternative/constitutive exons in functional genomic areas.</p

Facial Expression Synthesis Based on Imitation

[[abstract]]It is an interesting and challenging problem to synthesise vivid facial expression images. In this paper, we propose a facial expression synthesis system which imitates a reference facial expression image according to the difference between shape feature vectors of the neutral image and expression image. To improve the result, two stages of postprocessing are involved. We focus on the facial expressions of happiness, sadness, and surprise. Experimental results show vivid and flexible results.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子

Time-Delayed Magnetic Control and Narrowing of X-Ray frequency Spectra in Two-Target Nuclear Forward Scattering

Controlling and narrowing x-ray frequency spectra in magnetically perturbed two-target nuclear forward scattering is theoretically studied. We show that different hard-x-ray spectral redistributions can be achieved by single or multiple switching of magnetic field in nuclear targets. Our scheme can generate x-ray spectral lines with tenfold intensity enhancement and spectral width narrower than four times the nuclear natural linewidth. The present results pave the way towards a brighter and flexible x-ray source for precision spectroscopy of nuclear resonances using modern synchrotron radiation.Comment: 5 pages, 5 figure