1,765 research outputs found
The Effect of Orthographical and Phonological Similarities between Chinese and Japanese in an Oral Translation Task with Japanese Kanji-Words
The present study investigated the effect of orthographical and phonological similarities between Chinese and Japanese in an oral translation task with Japanese kanji words. The participants were asked to translate spoken Japanese kanji words into spoken Chinese. The results showed that two translation routes were used by the participants. With both high- and low-phonological-similarity words, a facilitatory effect of orthographic similarity was observed; with low-orthographic-similarity words. an inhibitory effect of phonological similarity was seen. These results suggest that in word translation, orthographic similarity exerts a similar effect in both comprehension and production. whereas phonological similarity has a different effect in comprehension and production
Magnetar Flare-Driven Bumpy Declining Light Curves in Hydrogen-poor Superluminous Supernovae
Recent observations indicate that hydrogen-poor superluminous supernovae
often display bumpy declining light curves. However, the cause of these
undulations remains unclear. In this paper, we have improved the magnetar
model, which includes flare activities. We present a systematic analysis of a
well-observed SLSNe-I sample with bumpy light curves in the late-phase. These
SLSNe-I were identified from multiple transient surveys, such as the
Pan-STARRS1 Medium Deep Survey (PS1 MDS) and the Zwicky Transient Facility
(ZTF). Our study provides a set of magnetar-powered model light curve fits for
five SLSNe-I, which accurately reproduce observed light curves using reasonable
physical parameters. By extracting essential characteristics of both explosions
and central engines, these fits provide valuable insights into investigating
their potential association with gamma ray burst engines. We found that the
SLSN flares tend to be the dim and long extension of the GRB flares in the peak
luminosity versus peak time plane. Conducting large-scale, high cadence surveys
in the near future could enhance our comprehension of both SLSN undulation
properties and their potential relationship with GRBs by modeling their light
curve characteristics.Comment: 10 pages, 5 figures. Accepted for publication in the Astrophysical
Journa
Mitochondrial DNA Instability in Cells Lacking Aconitase Correlates with Iron Citrate Toxicity
Aconitase, the second enzyme of the tricarboxylic acid cycle encoded by ACO1 in the budding yeast Saccharomyces cerevisiae, catalyzes the conversion of citrate to isocitrate. aco1Δ results in mitochondrial DNA (mtDNA) instability. It has been proposed that Aco1 binds to mtDNA and mediates its maintenance. Here we propose an alternative mechanism to account for mtDNA loss in aco1Δ mutant cells. We found that aco1Δ activated the RTG pathway, resulting in increased expression of genes encoding citrate synthase. By deleting RTG1, RTG3, or genes encoding citrate synthase, mtDNA instability was prevented in aco1Δ mutant cells. Increased activity of citrate synthase leads to iron accumulation in the mitochondria. Mutations in MRS3 and MRS4, encoding two mitochondrial iron transporters, also prevented mtDNA loss due to aco1Δ. Mitochondria are the main source of superoxide radicals, which are converted to H2O2 through two superoxide dismutases, Sod1 and Sod2. H2O2 in turn reacts with Fe2+ to generate very active hydroxyl radicals. We found that loss of Sod1, but not Sod2, prevents mtDNA loss in aco1Δ mutant cells. We propose that mtDNA loss in aco1Δ mutant cells is caused by the activation of the RTG pathway and subsequent iron citrate accumulation and toxicity
Tunable strong plasmon-exciton coupling based on borophene and deep subwavelength perovskite grating
Two-dimensional materials support deeply confined and tunable plasmonic
modes, which have great potential for achieving device miniaturization and
flexible manipulation. In this paper, we propose a diffraction-unlimited system
composed of borophene layer and perovskite grating to investigate the strong
coupling between the borophene guiding plasmon (BGP) and perovskite exciton
(PE) mode. The resonant energy of BGP mode could be electrically tuned to match
the energy of PE mode, and a remarkable Rabi splitting is attained under
zero-detuning condition. The splitting energy could reach 230 meV due to the
strong field enhancement provided by BGP mode. Consequently, an active
reflective phase modulation with 1.76{\pi} range is achieved by dynamically
manipulating the detuning. Furthermore, by increasing the distance between the
borophene layer and perovskite grating, a parity-time symmetry breaking could
be observed with the vanished energy splitting. Our results deepen the
understanding of light-matter interaction at the sub-wavelength scale and
provide a guideline for designing active plasmonic devices.Comment: 9 pages, 4 figure
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